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                                                                    EXHIBIT 10.4


                                                        BASIC LEASE INFORMATION



Lease Date:         August 22, 1988

Landlord:  Issaquah #1 Limited Partnership, a Texas limited partnership

Address of Landlord:  300 120th Avenue N.E.
                      Building 1, Suite 120
                      Bellevue, Washington 98005


Tenant:   BAXTER HEALTHCARE CORPORATION, a Delaware corporation

Premises:             I-90 Lake Place
                      2005 N.W. Sammamish Road
                      Building B, Suite 107
                      Issaquah, Washington 98027



Paragraph 1

"Premises" approximately 44,199 square feet in Building B of approximately
55,225 square feet (computed from measurements to the exterior of outside walls
of the building and to the center of interior walls), such premises being shown
and outlined in red on the plan attached hereto as Exhibit A, and being part of
the real property described in Exhibit B attached hereto.

Paragraph 1

Lease Term:  Commencing on the "Commencement Date" as hereinafter defined and
ending 60 months thereafter except that in the event the Commencement Date is a
date other than the first day of a calendar month, said term shall extend for
said number of months in addition to the remainder of the calendar month
following the Commencement Date.

Paragraph 1

Scheduled Term Commencement Date:  April 1, 1989


Paragraph 2    

Monthly Base Rent:                                                    $40,663.00





Paragraph 2B

Security Deposit:     $0.00

Paragraph 4A

Tenant's Initial Monthly Escrow Payment for Taxes and Other Charges:  $ 2,558.00

Paragraph 7  

Tenant's Initial Monthly Common Area Maintenance Charge:              $ 1,326.00

Paragraph 13B 

Tenant's Initial Monthly Insurance Escrow Payment:                    $   442.00


Tenant's Initial Monthly Payment Total:                               $42,431.00

                                     

The foregoing Basic Lease Information is hereby incorporated into and made a
part of this Lease.  Each reference in this Lease to any of the Basic Lease
Information shall mean the respective information herein above set forth and
shall be construed to incorporate all of the terms provided under the
particular Lease paragraph pertaining to such information. In the event of any
conflict between any Basic Lease Information and the Lease, the former shall
control.
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                                LEASE AGREEMENT


                                                Issaquah #1 Limited Partnership,
THIS LEASE AGREEMENT, made and entered into by and between a Texas limited
partnership hereinafter referred to as "Landlord", and Baxter Healthcare
Corporation, a Delaware corporation               , hereinafter referred to as 
"Tenant":


                                   WITNESSETH


1.   PREMISES AND TERM.

     A.  In consideration of the obligation of Tenant to pay rent as herein
     provided, and in consideration of the other terms, provisions and covenants
     hereof, Landlord hereby demises and leases to Tenant, and Tenant hereby
     takes and leases from Landlord those certain Premises as outlined in red on
     Exhibit "A" attached hereto (hereinafter referred to as the "Premises") and
     incorporated herein by reference, together with all rights, privileges,
     easements, appurtenances, and amenities belonging to or in any way
     pertaining to the Premises and together with the buildings and other
     improvements situated or to be situated upon land described in Exhibit "B"
     attached hereto.

     B.   TO HAVE AND TO HOLD the same for a term commencing on the
     "Commencement Date", as hereinafter declined, and ending thereafter as
     specified in the Basic Lease Information, attached hereto, (the "Lease
     Term"), provided, however, that, in the event the "Commencement Date" is a
     date other than the first day of a calendar month, said term shall extend
     for said number of months in addition to the remainder of the calendar 
     month following the "Commencement Date".

     C.   The "Commencement Date" shall be the Scheduled Term Commencement Date
     shown in the Basic Lease Information, attached hereto and incorporated
     herein by reference or the date upon which the Premises shall have been
     substantially completed in accordance with the plans and specifications
     described in Exhibit "C" and "C-1" excluding the installation of Tenant lab
     fixtures and equipment attached hereto and incorporated herein by
     reference, as evidenced by the Landlord's Architect's Certificate of
     Substantial Completion, whichever is earlier. If the premises shall not
     have been substantially completed as aforesaid by the Scheduled Term
     Commencement Date, Tenant's obligations to pay rent and its other
     obligations for payment under this Lease shall commence on the date the
     Premises are substantially completed as aforesaid, and Landlord shall not
     be liable to Tenant for any loss or damage resulting from such delay.
     Landlord shall notify Tenant in writing as soon as Landlord deems the
     Premises to be substantially completed and ready for occupancy. In the
     event that the Premises have not in fact been substantially completed as
     aforesaid, Tenant shall notify Landlord of its objections. Landlord shall
     have a reasonable time after delivery of such notice in which to take such
     corrective action as may be necessary, and shall notify Tenant in writing
     as soon as it deems such corrective action has been completed so that the
     Premises are substantially completed and ready for occupancy. The taking of
     possession by Tenant shall be deemed conclusively to establish that the
     Premises have been substantially completed in accordance with the plans and
     specifications and that the Premises are in good and satisfactory
     condition, as of when possession was so taken. Tenant acknowledges that no
     representations as to the repair of the Premises have been made by
     Landlord, unless such are expressly set forth in this Lease. After the
     Commencement Date, Tenant shall, upon demand, execute and deliver to
     Landlord a letter of acceptance of delivery of the Premises, specifying the
     Commencement Date and the rent commencement date, in recordable form. In
     the event of any dispute as to the substantial completion or work performed
     or required to be performed by Landlord, the certificate of Landlord's
     architect or general contractor shall be conclusive. See additional
     provisions in Paragraphs 31, 32, and 33.

2.   BASE RENT AND SECURITY DEPOSIT.

     A.   Tenant agrees to pay to Landlord Base Rent for the premises, in
     advance, without demand, deduction or set off, for the entire Lease Term
     hereof at the rate specified in the Basic Lease Information, payable in
     monthly installments. One such monthly installment shall be due and payable
     on the date hereof and a like monthly installment shall be due and payable
     on or before the first day of each calendar month succeeding the
     Commencement Date recited above during the Lease Term, except that the
     rental payment for any fractional calendar month at the commencement or end
     of the Lease period shall be prorated on the basis of a 30-day month.


     Tenant and Landlord hereby agree that in lieu of Tenant depositing
     $43,967.00 as security deposit with Landlord at the beginning of this Lease
     Agreement, Tenant will restore the premises to good condition, ordinary 
     wear and tear excepted.

3.   USE.  The Premises shall be used only for the purpose of general office,
     receiving, storing, shipping, assembly, light manufacturing, and selling
     (other than retail) products, materials and merchandise made and/or
     distributed by Tenant and for such other lawful purposes as may be
     incidental thereto. Outside storage, including without limitation, trucks
     and other vehicles, is prohibited without Landlord's prior written consent.
     Tenant shall at its own cost and expense obtain any and all licenses and
     permits necessary for its use of the Premises. Tenant shall comply with all
     governmental laws, ordinances and regulations applicable to the use of the
     Premises, and shall promptly comply with all governmental orders and
     directives including but not limited to those regarding the correction,
     prevention and abatement of nuisances in or upon, or connected with, the
     Premises, all at Tenant's sole expense. Tenant shall not permit any
     objectionable or unpleasant odors, smoke, dust, gas, noise or vibrations to
     emanate from the Premises, nor take any other action which would constitute
     a nuisance or would disturb or endanger any other tenants of the building
     in which the Premises are situated or unreasonably interfere with their use
     of their respective Premises. In addition to any other remedies Landlord
     may have for a breach by Tenant of the terms of this Section 3, Landlord
     shall have the right to have Tenant evicted from the Premises. Without
     Landlord's prior written consent, Tenant shall not













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     receive, store or otherwise handle any product, material or merchandise
     which is explosive or highly inflammable. Tenant will not permit the
     Premises to be used for any purpose or in any manner (including without
     limitation any method of storage) which would render the insurance thereon
     void or the insurance risk more hazardous or cause the State Board of
     Insurance or other insurance authority to disallow any sprinkler credits.
     In the event Tenant's use of Premises shall result in an increase in
     insurance premiums, Tenant shall be solely responsible for said increase.

4.   TAXES AND OTHER CHARGES. 
     A. Tenant agrees to pay upon presentation of appropriate tax bill its
     proportionate share of any and all real and personal property taxes,
     regular and special assessments, license fees and other charges of any
     kind and nature whatsoever, payable by Landlord as a result of any public
     or quasi-public authority, private party, or owner's association levy,
     assessment or imposition against, or arising out of Landlord's ownership
     of or interest in, the real estate described in Exhibit "B" attached
     hereto, together with the building and the grounds, parking areas,
     driveways, roads, and alleys around the building in which the Premises are
     located, or any part thereof (hereinafter collectively referred to as the
     "Charges"). Tenant's proportionate share of the Charges shall be computed
     by multiplying the Charges by a fraction, the numerator of which shall
     be the number of gross leasable square feet of floor space in the Premises
     and the denominator of which shall be the total applicable gross leasable
     square footage or such other equitable apportionment as may be adopted.

     B. If Tenant should fail to pay any charges required to be paid by Tenant
     hereunder, in addition to any other remedies provided herein, Landlord
     may, if it so elects, pay such or taxes, assessments, license fees and
     other charges. Any sums so paid by Landlord shall be deemed to be so much
     additional rental owing by Tenant to Landlord and due and payable upon
     demand as additional rental plus interest at the rate of one percent (1%)
     over prime rate at the Seafirst Bank per annum from the date of payment by 
     Landlord until repaid by Tenant.

     C. (1) If at any time during the Lease Term, the present method of
     taxation shall be changed so that in lieu of the whole or any part of any
     taxes, assessments, fees or charges levied, assessed or imposed on real
     estate and the improvements thereon, there shall be levied, assessed or
     imposed on Landlord a capital levy or other tax directly on the rents
     received therefrom and/or a franchise tax, assessment, levy or charge
     measured by or based, in whole or in part, upon such rents or the present
     or any future building or buildings, then all such taxes, assessments,
     fees or charges, or the part thereof so measured or based, shall be deemed
     to be included within the term "Charges" for the purposes hereof.

     (2) Tenant may, alone or along with Landlord and other tenants of the
     building containing the Premises, at its sole cost and expense, in its or
     their own name(s) dispute and contest any Charges by appropriate
     proceedings diligently conducted in good faith, but only after Tenant
     Landlord and all other tenants, if any, joining with Tenant in such
     contest have deposited with Landlord the amount so contested and unpaid or
     their proportionate shares thereof as the case may be, which shall be held
     by Landlord without obligation for interest until the termination of the
     proceedings, at which time the amount(s) deposited shall be applied by
     Landlord toward the payment of the items held valid (plus any court costs,
     interest, penalities and other liabilities associated with the
     proceedings), and Tenant's share of any excess shall be returned to
     Tenant. Tenant further agrees to pay to Landlord upon demand Tenant's
     share (as among all Tenants who participated in the contest) of all court
     costs, interest, penalities and other liabilities relating to such
     proceedings. Tenant hereby indemnifies and agrees to hold harmless the
     Landlord from and against any cost, damage or expense (including
     attorney's fees) in connection with any such proceedings.

     (3) Any payment to be made pursuant to this Paragraph 4 with respect to
     the calendar year in which this Lease commences or terminates shall bear
     the same ratio to the payment which would be required to be made for the
     full calendar year as that part of such calendar year covered by the Lease 
     Term bears to a full calendar year.

     (D) Tenant shall be liable for all taxes levied against personal property
     and trade fixtures placed by Tenant in the Premises. If any such taxes are
     levied against Landlord or Landlord's property and if Landlord elects to
     pay the same or if the assessed value of Landlord's property is increased
     by inclusion of personal property and trade fixtures placed by Tenant in
     the Premises and Landlord elects to pay the taxes based on such increase,
     Tenant shall pay to Landlord upon demand that part of such taxes for which
     Tenant is primarily liable hereunder.

     5. TENANT'S MAINTENANCE.
     A. After reasonable notice from Landlord, Tenant shall at its own cost and
     expense keep and maintain all parts of the Premises (except those for
     which Landlord is expressly responsible under the terms of this Lease) in
     good condition, promptly making all necessary repair and replacements,
     including but not limited to, windows, glass and plate glass, doors, any
     special office entry, interior walls and finish work, floor and floor
     covering, downspouts, gutters, heating and air conditioning systems, dock
     boards, truck doors, dock bumpers, plumbing work and fixtures, termite and
     pest extermination, regular removal of trash and debris, keeping the
     whole of the Premises in a clean and sanitary condition. Tenant shall not
     be obligated to repair any damage caused by fire, tornado, or other
     casualty covered by the insurance to be maintained by Landlord pursuant to
     subparagraph 13(A) below, except that Tenant shall be obligated to repair
     all wind damage to glass except with respect to tornado or hurricane
     damage. Landlord shall repair and pay for damage caused by negligence of
     Landlord or Landlord's employees.

     B. Tenant shall not damage any demising wall or disturb the integrity and
     support provided by any demising wall and shall, at its sole cost and
     expense, promptly repair any damage or injury to any demising wall caused
     by Tenant or it employees, agents, licensees or invitees.

     C. Tenant and its employees, customers and licensees shall have the right
     to use the parking areas, if any, subject to rights of ingress and egress
     of other tenants. Landlord shall not be responsible for enforcing Tenant's
     exclusive parking rights against any third parties. If Tenant or any other
     particular tenant of the building can be clearly identified as being
     responsible for obstructions or stoppage of


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a common sanitary sewage line, then Tenant, if Tenant is responsible, or such
other responsible Tenant, shall pay the entire cost thereof, upon demand, as
additional rent.

D. Tenant shall, at its own cost and expense, enter into a regularly scheduled
preventive maintenance/service contract with a maintenance contract or for
servicing all heating and air conditioning systems and equipment within the
Premises.

6. LANDLORD'S REPAIRS. After reasonable notice from Tenant, Landlord shall
repair the roof, exterior walls, floors and foundations, (normal settling
excepted). Tenant shall repair and pay for any damage to such items to be
maintained by Landlord caused by any act, omission or negligence of Tenant, or
Tenant's employees, agents, licensees or invitees, or caused by Tenant's default
hereunder. The term "walls" as used herein shall not include windows, glass or
plate glass, doors, special store fronts or office entries. Tenant shall
promptly give Landlord written notice of defect or need for repairs, after which
Landlord shall have a reasonable opportunity and time to repair same or cure
such defect. Landlord's liability with respect to any defects, repairs or
maintenance for which Landlord is responsible under any of the provisions of
this Lease shall be limited to the cost of such repairs or maintenance or the
curing of such defect.

7.  MONTHLY COMMON AREA MAINTENANCE CHARGE. Tenant agrees to pay as an
additional charge each month for its proportionate share of the cost of
operation and maintenance of the Common Area which shall be defined from time to
time by Landlord. Common Area costs which may be incurred by Landlord at its
discretion, shall include, but not limited to those costs incurred for lighting,
water, sewage, trash removal, exterior painting, exterior window cleaning,
sweeping, management, accounting, policing, inspecting, sewer lines, plumbing,
paving, landscape maintenance, plant material replacement and other like
charges, and Landlord's fees for supervision and administration of the items set
forth in this paragraph, currently at 10%. Landlord shall maintain the Common
Areas in reasonably good condition and repair. The proportionate share to be
paid by Tenant of the cost of operation and maintenance of the Common Area shall
be computed on the ratio that the gross leaseable square feet of the Premises
bears to the total applicable gross leaseable square footage or such other
equitable apportionment as may be adopted. Landlord shall make monthly or other
periodic charges based upon the estimated annual cost of operation and
maintenance of the Common Area, payable in advance but subject to adjustment
after the end of the year on the basis of the actual cost for such year. Any
such periodic charges shall be due and payable upon delivery of notice thereof.
The initial Common Area Maintenance Charge, subject to adjustment as provided
herein, shall be due and payable, as additional rent, at the same time and in
the same manner as the time and manner of the payment of monthly rental as
provided herein. The amount of the initial Common Maintenance Charge shall be as
specified in the Basic Lease Information.

8.  ALTERATIONS.  Tenant shall not make any alterations, additions or
improvements to the Premises (including but not limited to roof and wall
penetrations) which cost in excess of $10,000.00 per project without the prior
written consent of Landlord which shall not be reasonably withheld. Tenant may,
without the consent of Landlord, but at its own cost and expense and in a good
workmanlike manner erect such shelves, bins, machinery and trade fixtures as it
may deem advisable, without altering the basic character of the building or
improvements and without overloading or damaging such building or improvements,
and in each case complying with all applicable governmental laws, ordinances,
regulations and other requirements. All alterations, additions, improvements and
partitions erected by Tenant shall be and remain the property of Tenant during
the Term of this Lease and Tenant shall, unless Landlord otherwise elects as
hereinafter provided, remove all alterations, additions, improvements and
partitions erected by Tenant and restore the Premises to their original
condition by the date of termination of this Lease or upon earlier vacating of
the Premises, provided, however, that if Landlord so elects prior to termination
of this Lease or upon earlier vacating of the Premises, such alterations,
additions, improvements and partitions shall become the property of Landlord as
of the date of termination of this Lease or upon earlier vacating of the
Premises and shall be delivered up to the Landlord with the Premises. All
shelves, bins, machinery and trade fixtures installed by Tenant may be removed
by Tenant prior to the termination of this Lease if Tenant so elects, and shall
be removed by the date of termination of this Lease or upon earlier vacating of
the Premises if required by Landlord; upon any such removal Tenant shall restore
the Premises to their original condition. All such removals and restoration
shall be accomplished in good workmanlike manner so as not to damage the primary
structure of structural qualities of the buildings and other improvements
situated on the Premises.

9.  SIGNS. Tenant shall not install signs upon the Premises without Landlord's
prior written approval, and any such signage shall be subject to any applicable
governmental laws, ordinances, regulations and other requirements. Tenant shall
remove all such signs by the termination of this Lease. Such installations and
removals shall be made in such a manner as to avoid injury or defacement of the
building and other improvements, and Tenant shall repair any injury or
defacement, including without limitation discoloration, caused by such
installation and/or removal.

10. INSPECTION.

A. Landlord and Landlord's agents and representatives shall have the right
provided Landlord shall give Tenant prior notice and shall be accompanied by
employee of Tenant to enter and inspect the Premises at any reasonable time
during business hours, for the purpose of ascertaining the condition of the
Premises or in order to make such repairs as may be required or permitted to be
made by Landlord under the terms of this Lease. During the period that is six
(6) months prior to the end of the Term hereof, Landlord and Landlord's agents
and representatives shall have the right to enter the Premises at any reasonable
time during business hours for the purpose of showing the Premises and shall
have the right to erect on the Premises a suitable sign indicating the Premises
are available.

B. Tenant shall give written notice to Landlord at least thirty (30) days prior
to vacating the Premises and shall arrange to meet with Landlord for a joint
inspection of the Premises prior to vacating. In the event of Tenant's failure
to give such notice or arrange such joint inspection, Landlord's inspection at
or after Tenant's vacating the Premises shall be conclusively deemed correct for
purposes of determining Tenant's responsibility for repairs and restoration. It
shall be the responsibility of Tenant, prior to vacating the Premises, to clean
and repair the Premises and restore them to the condition in which they were in
upon delivery of the Premises to Tenant at the Commencement Date, reasonable
wear and tear excepted. Cleaning, repair and restoration shall include, but not
be limited to, removal of all trash, cleaning of walls, where necessary, of
carpet and flooring broom clean, replacement of light bulbs and tubes, cleaning
and wiping down of all fixtures, maintenance and repair of all heating and air
conditioning systems, and all similar work, which shall be done at the latest
practical date prior to vacation of the Premises.

11. UTILITIES. Landlord agrees to provide at its cost water, electricity and gas
service connections into the Premises; but Tenant shall pay for all water, gas,
heat, light, power, telephone, sewer, sprinkler charges and other utilities and
services used on or from the Premises, together with any taxes, penalties,
surcharges or the



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     like pertaining thereto and any maintenance charges for utilities and shall
     furnish all electric light bulbs and tubes. If any such services are not
     separately metered to Tenant, Tenant shall pay a reasonable proportion as
     determined by Landlord of all charges jointly metered with other Premises.
     Landlord shall in no event be liable for any interruption or failure of
     utility services on the Premises, unless such interruption results from
     Landlord's intentional wrongful act and Landlord's negligence in its
     efforts to restore.

12.  ASSIGNMENT AND SUBLETTING.

     A.   Tenant shall not have the right, voluntarily or involuntarily, to
     assign, convey, transfer, mortgage or sublet the whole or any part of the
     Premises under this Lease without the prior written consent of Landlord
     which shall not be unreasonably withheld. In the event Tenant applies to
     Landlord for consent to assign, convey, transfer or sublet the Premises,
     Landlord may condition such consent upon the right to receive one-half of
     the profit, if any, which Tenant may realize on account of such assignment,
     conveyance, transfer or sublease of the Premises. For purposes of this
     paragraph, "profit" shall mean any sum which the assignee, sublessee or
     transferree is required to pay, or which is credited to Tenant as rent in
     excess of the Rents required to be paid by Tenant to Landlord under this
     Lease. Landlord also reserves the right to recapture the Premises or
     applicable portion thereof in lieu of giving its consent by notice given to
     Tenant within twenty (20) days after receipt of Tenant's written request
     for assignment or subletting. Such recapture shall terminate this Lease as
     to the applicable space effective on the prospective date of assignment or
     subletting, which shall be the last day of a calendar month and not earlier
     than sixty (60) days after receipt of Tenant's request hereunder. In the
     event that Landlord shall not elect to recapture and shall thereafter give
     its consent, Tenant shall pay Landlord a reasonable fee, not to exceed
     $200.00 to reimburse Landlord for processing costs incurred in connection
     with such consent.

     B.   Notwithstanding any permitted assignment or subletting, Tenant shall
     at all times remain directly, primarily and fully responsible and liable
     for the payment of the rent herein specified and for compliance with all of
     its other obligations under the terms, provisions and covenants of this
     Lease. Upon the occurrence of an "event of default" as hereinafter defined,
     if the Premises or any part thereof are then assigned or sublet, Landlord,
     in addition to any other remedies herein provided, or provided by law, may
     at its option collect directly from such assignee or subtenant all rents
     becoming due to Tenant under such assignment, transfer or sublease and
     apply such rent against any sums due to Landlord from Tenant hereunder, and
     no such collection shall be construed to constitute a novation or a release
     of Tenant from the further performance of Tenant's obligations hereunder.

13.  INSURANCE, FIRE AND CASUALTY DAMAGE.

     A.   Landlord agrees to maintain insurance covering the building of which
     the Premises are a part in an amount not less than eighty percent (80%) (or
     such greater percentage as may be necessary to comply with the provisions
     of any co-insurance clauses of the policy) of the "replacement cost"
     thereof as such term is defined in the Replacement Cost Endorsement to be
     attached thereto, insuring against the perils of Fire, Lightning, Extended
     coverage, Vandalism and Malicious Mischief, extended by Special Extended
     coverage Endorsement to insure against all other Risks of Direct Physical
     Loss, such coverages and endorsements to be as defined, provided and
     limited in the standard bureau forms prescribed by the insurance regulatory
     authority for the State in which the Premises are situated for use by
     insurance companies admitted in such state for the writing of such
     insurance on risks located within such state. Subject to the provisions of
     subparagraph 13, C,D,E below, such insurance shall be for the sole benefit
     of Landlord and under its sole control. In the event the insurance policy
     shall contain a deductible, Tenant shall be liable for and pay any
     deductible withheld from insurance proceeds of payable under the terms of
     the insurance policy in the event of a claim or insured loss thereunder.

     B.   Tenant agrees to pay its proportionate share of Landlord's cost of
     carrying fire and extended coverage insurance ("Insurance") on the
     building. During each month of the term of this Lease, Tenant shall make a
     monthly escrow deposit with Landlord equal to one-twelfth of its
     proportionate share of the Insurance on the buildings and grounds which
     will be due and payable for that particular year. Tenant authorizes
     Landlord to use the funds deposited by him with Landlord under this
     paragraph to pay the cost of such Insurance. Each Insurance Escrow payment
     shall be due and payable, as additional rent, at the same time and manner
     of the payment of the monthly rental as provided herein. The initial share
     of the estimated Insurance for the year in question, and the monthly
     Insurance Escrow Payment is subject to increase or decrease as determined
     by Landlord to reflect an accurate monthly escrow of Tenant's estimated
     proportionate share of this Insurance. The Insurance Escrow Payment account
     of Tenant shall be reconciled annually. If the Tenant's total Insurance
     Escrow Payments are less than Tenant's actual pro rata share of the
     Insurance, Tenant shall pay to Landlord upon demand the difference; if the
     total Insurance Escrow Payments of Tenant are more than Tenant's actual pro
     rata share of the Insurance, Landlord shall promptly refund the balance of
     such excess to Tenant after first crediting the excess to the next monthly
     payment by Tenant for its proportionate share of Taxes and Insurance.
     Tenant's cost of insurance shall be computed by multiplying the cost of
     Insurance by a fraction, the numerator of which shall be the number of
     gross leaseable square feet of floor space in the Premises and the
     denominator of which shall be the total applicable gross leasable square
     footage. The amount of the initial monthly Insurance Escrow Payment will be
     as specified in the Basic Lease Information.

     C.   If the building, of which the Premises are a part, should be damaged
     or destroyed by fire, tornado or other casualty, Tenant shall give prompt
     written notice thereof to Landlord.

     D.   If the building, of which the Premises are a part, should be totally
     destroyed by fire, tornado or other casualty, or if it should be so damaged
     thereby that rebuilding or repairs cannot in Landlord's estimation be
     completed within two hundred (200) days after the date of damage, this
     Lease shall terminate and the rent shall be abated during the unexpired
     portion of this Lease, effective upon the date of the occurrence of such
     damage. Landlord shall give notice to Tenant in writing of its
     determination to terminate this Lease within ninety (90) days following the
     date of the occurrence of such damage.

     E.   If the building, of which the Premises are a part, should be damaged
     by any peril covered by the Insurance to be provided by Landlord under
     subparagraph 13(A) above, but only to such extent that rebuilding or
     repairs can in Landlord's estimation be completed within two hundred (200)
     days after the date of such damage, this Lease shall not terminate, and
     Landlord shall at its sole cost and expense thereupon proceed with
     reasonable diligence to rebuild and repair such building to substantially
     the condition in which it existed prior to such damage, except that
     Landlord shall not be required to rebuild, repair or replace any part of
     the partition, fixtures, additions and other improvements which may have
     been placed in, or about the Premises by Tenant. If the Premises are
     untenantable in whole or in part following such damage, the rent payable
     hereunder during the period in which they are untenantable shall be reduced
     to such extent as may be fair and reasonable under all of the
     circumstances. In the event that Landlord shall fail to complete such
     repairs and rebuilding within two hundred (200) days after the date 

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     of such damage, Tenant may at its option terminate this Lease by delivering
     written notice of termination to Landlord as Tenant's exclusive remedy,
     whereupon all rights and obligations hereunder shall cease and terminate.

     F.   Notwithstanding anything herein to the contrary, in the event the
     holder of any indebtedness secured by a mortgage or deed of trust covering
     the Premises requires that the Insurance proceeds be applied to such
     indebtedness, then Landlord shall have the right to terminate this Lease
     by delivering written notice of termination to Tenant within fifteen (15)
     days after such requirement is made by any such holder, whereupon all
     rights and obligations hereunder shall cease and terminate.

     G.   Each of Landlord and Tenant hereby releases the other from any loss
     or damage to property caused by fire or any other perils insured through
     or under them by way of subrogation or otherwise for any loss or damage to
     property caused by fire or any other perils insured in policies of
     Insurance covering such property, even if such loss or damage shall have
     been caused by the fault or negligence of the other party, or anyone for
     whom such party may be responsible; provided, however, that this release
     shall be applicable and in force and effect only with respect to loss or
     damage occurring during such times as the releasor's policies shall
     contain a clause or endorsement to the effect that any such release shall
     not adversely affect or impair said policies or prejudice the right of the
     releasor to recover thereunder and then only to the extent of the
     Insurance proceeds payable under such policies. Each of the Landlord and
     Tenant agrees that it will request its Insurance carriers to include in
     its policies such a clause or endorsement. If extra cost shall be charged
     therefor, each party shall advise the other thereof and of the amount of
     the extra cost, and the other party, at its election, may pay the same,
     but shall not be obligated to do so.

14.  LIABILITY.  Landlord shall not be liable to Tenant or Tenant's employees,
     agents, servants, guests, invitees or visitors, or to any other person
     whomsoever, for any injury to person or damage to property on or about the
     Premises, resulting from and/or caused in part or whole by the negligence
     or misconduct of Tenant, its employees, agents, servants, guests, invitees
     or visitors, or of any other person entering upon the Premises, or caused 
     by the building and improvements located on the Premises becoming out of
     repair, or caused by leakage of gas, oil, water or steam or by electricity
     emanating from the Premises, or due to any cause whatsoever, and Tenant
     hereby covenants and agrees that it will at all times indemnify and hold
     safe and harmless the property, the Landlord (including without limitation
     the trustee and beneficiaries if Landlord is a trust), Landlord's
     employees, agents, servants, guests, invitees, and visitors from any loss,
     liability, claims, suits, costs, expenses, including without limitation
     attorney's fees and damages, both real and alleged, arising out of any
     such damage or injury; except injury to persons or damage to property the
     sole cause of which is the negligence of Landlord or the failure of
     Landlord to repair any part of the Premises which Landlord is obligated to
     repair and maintain hereunder within a reasonable time after the receipt
     of which Landlord is obligated to repair and maintain hereunder within a
     reasonable time after the receipt of written notice from Tenant of needed
     repairs. Tenant shall procure and maintain throughout the term of this
     Lease a policy or policies of Insurance, at its sole cost and expense,
     insuring both Landlord and Tenant against all claims, demands or actions
     arising out of or in connection with: (i) the Premises; (ii) the
     condition of the Premises; (iii) Tenant's operations in and maintenance
     and use of the Premises; and (iv) Tenant's liability assumed under this
     Lease, the limits of such policy or policies to be in the amount of not
     less than $1,000,000 per occurrence in respect of injury to persons
     (including death) and in respect of property damage or destruction,
     including loss of use thereof. All such policies shall be procured by
     Tenant from responsible Insurance companies authorized to do business in
     the State of Washington satisfactory to Landlord. Certificates of
     Insurance shall be delivered to Landlord prior to the commencement date of
     this Lease. Not less that fifteen (15) days prior to the expiration date
     of such policies, Certificates of Insurance certified copies of the
     renewals thereof shall be delivered to Landlord. Such policies shall
     further provide that not less than thirty (30) days written notice shall
     be given to Landlord before such policy may be cancelled or changed to
     reduce insurance provided thereby.

15.  CONDEMNATION.

     A.   If the whole or any substantial part of the Premises should be taken
     for any public or quasi-public use under governmental law, ordinance or
     regulation, or by right of eminent domain, or by private purchases in lieu
     thereof and the taking would prevent or materially interfere with the use
     of the Premises for the purpose for which they are being used, this lease
     shall terminate and the rent shall be abated during the unexpired portion
     of this Lease, effective when the physical taking of said Premises shall
     occur.

     B.   If part of the Premises shall be taken for any public or quasi-public
     use under any governmental law, ordinance or regulation, or by right of
     eminent domain, or by private purchase in lieu thereof, and this Lease is
     not terminated as provided in the subparagraph above, this Lease shall not
     terminate but the rent payable hereunder during the unexpired portion of
     this Lease shall be reduced to such extent as may be fair and reasonable
     under all of the circumstances.

     C.   In the event of any such taking or private purchase on lieu thereof,
     Landlord shall be entitled to receive the entire award. Tenant shall be
     entitled to make a claim in any condemnation proceedings which does not
     reduce the amount of Landlord's award, for the value of any furniture,
     furnishings and fixtures installed by and at the sole expense of Tenant.

16.  HOLDING OVER. Tenant will, at the termination of this Lease by lapse of
     time or otherwise, yield up immediate possession to Landlord. If Landlord
     agrees in writing that Tenant may hold over after the expiration or
     termination of this Lease, unless the parties hereto otherwise agree in
     writing on the terms of such holding over, the hold over tenancy shall be
     subject to termination by Landlord at any time upon not less than five (5)
     days advance written notice, or by Tenant at any time upon not less than
     thirty (30) days advance written notice, and all of the other terms and
     provisions of this Lease shall be applicable during that period, except
     that Tenant shall pay Landlord from time to time upon demand, as rental
     for the period of any hold over, an amount equal to one and one-half
     (1-1/2) the Base Rent in effect on the termination date, plus all
     additional rental as defined herein, computed on a daily basis for each
     day of the hold over period. No holding over by Tenant, whether with or
     without consent to Landlord, shall operate to extend this Lease except as
     otherwise expressly provided. The preceding provisions of this paragraph
     16 shall not be construed as Landlord's consent for Tenant to hold over.

17.  QUIET ENJOYMENT. Landlord covenants that it now has, or will acquire
     before Tenant takes possession of the Premises, good fee or leasehold
     title to the Premises, free and clear of all liens and encumbrances,
     excepting only the lien for current taxes not yet due, such mortgage or
     mortgages as are permitted by the



                                       5
                                        
<PAGE>   7
     terms of this Lease, zoning ordinances and other building and fire
     ordinances and governmental regulations relating to the use of such
     property, and easements, restrictions and other conditions of record.
     Landlord represents and warrants that it has full right and authority to
     enter into this Lease and that Tenant, upon paying the rental herein set
     forth and performing its other covenants and agreements herein set forth,
     shall peaceably and quietly have, hold and enjoy the Premises for the term
     hereof without hindrance or molestation from Landlord subject to the terms
     and provisions of this Lease.

18.  EVENTS OF DEFAULT.  The following events shall be deemed to be events of
     default by Tenant under this Lease:

     A.  Tenant shall fail to pay any installment of the rent herein reserved
     when due, or any payment with respect to taxes hereunder when due, or any
     other payment or reimbursement to Landlord required herein when due, and
     such failure shall continue for a period of ten (10) days from the date
     such payment was due.

     B.  Tenant shall become insolvent, or shall make transfer in fraud of
     creditors, or shall make an assignment for the benefit of creditors.

     C.  Tenant shall file a petition under any section or chapter of the
     National Bankruptcy Act, as amended, or under any similar law or statute of
     the United States or any State thereof; or Tenant shall be adjudged
     bankrupt or insolvent in proceedings filed against Tenant thereunder.

     D.  A receiver or trustee shall be appointed for all or substantially all
     of the assets of Tenant.

     E.  Tenant shall desert of the Premises.

     F.  Tenant shall fail to comply with any term, provision or covenant of
     this Lease (other than the foregoing in this Paragraph 18), and shall not
     cure such failure within twenty (20) days after written notice thereof to
     Tenant.

19.  REMEDIES. Upon the occurrence of any such events of default described in
     Paragraph 18 hereof, Landlord shall have the option to pursue any one or
     more of the following remedies without any notice or demand whatsoever.

     A.  Landlord may accelerate all rent payments due hereunder which shall
     then become immediately due and payable.

     B.  Terminate this Lease, in which event Tenant shall immediately
     surrender the Premises to Landlord, and if Tenant fails so to do, Landlord
     may, without prejudice to any other remedy which it may have for possession
     or arrearages in rent, enter upon and take possession of the Premises and
     expel or remove Tenant and any other person who may be occupying such
     Premises or any  part thereof, without being liable for prosecution or any
     claim of damages therefor, and Tenant agrees to pay to Landlord on demand
     the amount of all loss and damage which Landlord may suffer by reason of
     such termination, whether through inability to relet the Premises on
     satisfactory terms or otherwise.

     C.  Enter upon and take possession of the Premises and expel or remove
     Tenant and any other person who may be occupying such Premises or any part
     thereof, without being liable for prosecution or any claim for damages
     therefor, and relet the Premises for such terms ending before, on or after
     the expiration date of the Lease Term, at such rentals and upon such other
     conditions (including concessions and prior occupancy periods) as Landlord
     in its sole discretion may determine, and receive the rent therefor; and
     Tenant agrees to pay to the Landlord on demand any deficiency that may
     arise by reason of such reletting. Landlord shall have no obligation to
     relet the Premises or any part thereof and shall not be liable for refusal
     or failure to relet or in the event of reletting for refusal or failure to
     collect any rent due upon such reletting. In the event Landlord is
     successful in reletting the Premises at a rental in excess of that agreed
     to be paid by Tenant pursuant to the terms of this Lease, Landlord and
     Tenant each mutually agree that Tenant shall not be entitled, under any
     circumstances, to such excess rental, and Tenant does hereby specifically
     waive any claim to such excess rental.

     D.  Enter upon the Premises, without being liable for prosecution or
     any claim for damages therefor, and do whatever Tenant is obligated to do
     under the terms of this Lease; and Tenant agrees to reimburse Landlord on
     demand for any expenses which Landlord may incur in thus effecting
     compliance with Tenant's obligations under this Lease, and Tenant further
     agrees that Landlord shall not be liable for any damages resulting to the
     Tenant from such action, unless caused by the negligence of Landlord.

     E.  Whether or not Landlord retakes possession or relets the Premises,
     Landlord shall have the right to recover unpaid rent and all damages caused
     by Tenant's default, including attorney's fees. Damage shall include,
     without limitation; all rentals lost, all legal expenses and other related
     costs incurred by Landlord following Tenant's default, all costs incurred
     by Landlord in restoring the Premises to good order and condition, or in
     remodeling, renovating or otherwise preparing the Premises for reletting,
     all costs (including without limitation any brokerage commissions and the
     value of Landlord's time) incurred by Landlord, plus interest thereon from
     the date of expenditure until fully repaid at the rate of eighteen percent
     (18%) per annum.

     F.  In the event Tenant fails to pay any installment of rent, additional
     rent or other charges hereunder as and when such installment is due, to
     help defray the additional cost to Landlord for processing such late
     payments Tenant shall pay to Landlord on demand a late charge in an amount
     equal to five percent (5%) of such installment; and the failure to pay
     such amount within ten (10) days after demand therefor shall be an event
     of default hereunder. The provision for such late charge shall be in
     addition to all of Landlord's other rights and remedies hereunder or at
     law and shall not be construed as liquidated damages or as limiting
     Landlord's remedies in any manner.

     G.  Pursuit of any of the foregoing remedies shall not preclude pursuit of
     any of the other remedies herein provided or any other remedies provided
     by law, such remedies being cumulative and non-exclusive, nor shall
     pursuit of any remedy herein provided constitute a forfeiture or waiver of
     any rent due to Landlord hereunder or of any damages accruing to Landlord
     by reason of the violation of any of the terms, provisions and covenants
     herein contained. No act or thing done by the Landlord or its agents during
     the Lease Term hereby granted shall be deemed a termination of this Lease
     or an acceptance of the surrender of the Premises, and no agreement to
     terminate this Lease or accept a surrender of said Premises shall be valid
     unless in writing signed by Landlord. No waiver by Landlord of any
     violation or breach of any of the terms, provisions and covenants herein
     contained shall be deemed or construed to constitute a waiver of any other
     violation or breach of any of the terms, provisions and covenants herein
     contained. Landlord's acceptance of the payment of rental or other
     payments hereunder after the occurrence of an event of default shall not
     be construed as a


                                       6
<PAGE>   8
     waiver of such default, unless Landlord so notifies Tenant in writing.
     Forbearance by Landlord to enforce one or more of the remedies herein
     provided upon an event of default shall not be deemed or construed to
     constitute a waiver of such default or of Landlord's right to enforce any
     such remedies with respect to such default or any subsequent default. If,
     on account of any breach or default by Tenant in Tenant's obligations under
     the terms and conditions of this Lease, it shall become necessary or
     appropriate for Landlord to employ or consult with an attorney concerning
     or to enforce or defend any of Landlord's rights or remedies hereunder,
     Tenant agrees to pay any reasonable attorney's fees so incurred.

20.  LANDLORD'S LIEN.  Landlord shall have all rights of Landlord's Lien in
     accordance with the State of Washington Statutes.

21.  MORTGAGES.  Tenant accepts this Lease subject and subordinate to any
     mortgage(s) and/or deed(s) of trust now or at any time hereafter
     constituting a lien or charge upon the Premises or the improvements
     situated thereon, provided, however, that if the mortgagee, trustee, or
     holder of any such mortgage or deed of trust elects to have Tenant's
     interest in this Lease superior to any such instrument, then by notice to
     Tenant from such mortgagee, trustee or holder, this Lease shall be deemed
     superior to such lien, whether this Lease was executed before or after
     said mortgage or deed of trust. Tenant shall at any time hereafter on
     demand execute any instruments, releases or other documents which may be
     required by any mortgagee for the purpose of subjecting and subordinating
     this Lease to the lien of any such mortgage.

22.  LANDLORD'S DEFAULT.  In the event Landlord should become in default in any
     payment due on any such mortgage described in Paragraph 21 hereof or in the
     payment of taxes or any other item which might become a lien upon the
     Premises and which Tenant is not obligated to pay under the terms and
     provisions of this Lease. Tenant is authorized and empowered after giving
     Landlord five (5) days prior written notice of such default and Landlord's
     failure to cure such default, to pay any such items for and on behalf of
     Landlord, and the amount of any item so paid by Tenant for or on behalf of
     Landlord, together with any interest or penalty required to be paid in
     connection therewith, shall be payable on demand by Landlord to Tenant;
     provided, however, that Tenant shall not be authorized and empowered to
     make any payment under the terms of this Paragraph 22 unless the item paid
     shall be superior to Tenant's interest hereunder. In the event Tenant pays
     any mortgage debt in full, in accordance with this paragraph, it shall, at
     its election, be entitled to the mortgage security by assignment or
     subrogation.

23.  MECHANICS LIENS.  Tenant shall have no authority, express or implied, to
     create or place any lien or encumbrance of any kind or nature whatsoever
     upon, or in any manner to bind, the interest of Landlord in the Premises or
     to charge the rentals payable hereunder for any claim in favor of any
     person dealing with Tenant, including those who may furnish materials or
     perform labor for any construction or repairs, and each such claim shall
     affect and each such lien shall attach to, if at all, only the leasehold
     interest granted to Tenant by this instrument. Tenant covenants and agrees
     that it will pay or cause to be paid all sums legally due and payable by it
     on account of any labor performed or materials furnished in connection with
     any work performed on the Premises on which any lien is or can be validly
     and legally asserted against its leasehold interest in the Premises or the
     improvements thereon and that it will save and hold Landlord harmless from
     any and all loss, cost or expense based on or arising out of asserted
     claims or liens against the leasehold estate or against the right, title
     and interest of the Landlord in the Premises or under the terms of this
     Lease.

24.  NOTICES.  Each provision of this instrument or of any applicable
     governmental laws, ordinances, regulations and other requirements with
     reference to the sending, mailing or delivery of any notice or the making
     of any payment by Landlord to Tenant or with reference to the sending,
     mailing or delivery of any notice or the making of any payment by Tenant
     to Landlord shall be deemed to be complied with when and if the following
     steps are taken:

     A.  All rent and other payments required to be made by Tenant to Landlord
     hereunder shall be payable to Landlord at the address hereinbelow set
     forth or at such other address as Landlord may specify from time to time
     by written notice delivered in accordance herewith. Tenant's obligation to
     pay rent and any other amounts to Landlord under the terms of this Lease
     shall not be deemed satisfied until such rent and other amounts have been
     actually received by Landlord.

     B.  All payments required to be made by Landlord to Tenant hereunder shall
     be payable to Tenant at the address hereinbelow set forth, or at such
     other address within the continental United States as Tenant may specify
     from time to time by written notice delivered in accordance herewith.

     C.  Any notice or document required or permitted to be delivered hereunder
     shall be deemed to be delivered when actually received. Certified or
     Registered Mail, addressed to the parties hereto at the respective
     addressed out below, or at such other address as they have theretofore
     specified by written notice delivered in accordance herewith:

     LANDLORD:                          TENANT:
     ISSAQUAH #1 LIMITED PARTNERSHIP    BAXTER HEALTHCARE CORPORATION
     300 120th Avenue N.E.              One Baxter Parkway
     Building 1, Suite 120              Deerfield, Illinois 60015
     Bellevue, Washington 98005         Attn: Director, Corporate Real Estate

     If and when include within the term "Landlord", as used in this instrument,
     there are more than one person, firm or corporation, all shall jointly
     arrange among themselves for their joint execution of such a notice
     specifying some individual at some specific address for the receipt of
     notices and payments to Landlord: if and when included within the term
     "Tenant", as used in this instrument, there are more than one person, firm
     or corporation, all shall jointly arrange among themselves for their joint
     execution of such a notice specifying some individual at some specific
     address within the continental United States for the receipt of notices and




                                       7

<PAGE>   9
payments to Tenant. All parties included within the terms "Landlord" and
"Tenant", respectively, shall be bound by notices given in accordance with the
provisions of this paragraph to the same effect as if each had received such
notice.

25.  MISCELLANEOUS.

     A.   Words of any gender used in this Lease shall be held and construed to
     include any other gender, and words in the singular number shall be held
     to include the plural, unless the context otherwise requires.

     B.   The terms, provisions and covenants and conditions contained in this
     Lease shall apply to, inure to the benefit of, and be binding upon, the
     parties hereto and upon their respective heirs, legal representatives,
     successors and permitted assigns, except as otherwise herein expressly
     provided. Landlord shall have the right to assign any of its rights and
     obligations under this Lease. Each party agrees to furnish to the other
     promptly upon demand, a corporate resolution, proof of due authorization
     by partners or other appropriate documentation evidencing the due
     authorization of such party to enter into this Lease.

     C.   The captions inserted in this Lease are for the convenience only and
     in no way define, limit or otherwise describe the scope or intent of this
     Lease, or any provision hereof, or in any way affect the interpretation of
     this Lease.

     D.   Tenant agrees from time to time within ten (10) days after request of
     Landlord, to deliver to Landlord, or Landlord's designee, an estoppel
     certificate stating that this Lease is in full force and effect, the date
     to which rent has been paid, the unexpired term of this Lease and such
     other matters pertaining to this Lease as may be requested by Landlord. It
     is understood and agreed that Tenant's obligation to furnish such estoppel
     certificates in a timely fashion is a material inducement for Landlord's
     execution of this Lease.

     E.   This Lease may not be altered, changed or amended except by an
     instrument in writing signed by both parties hereto.

     F.   All obligations of Tenant hereunder not fully performed as of the
     expiration or earlier termination of the term of this Lease shall survive
     the expiration or earlier termination of the Term hereof, including without
     limitation all payment obligations with respect to taxes and insurance and
     all obligations concerning the condition of the Premises. Tenant shall
     also, prior to vacating the Premises, pay to Landlord the amount, as
     estimated by Landlord, of Tenant's obligation hereunder for real estate
     taxes and insurance premiums for the year in which the Lease expires or
     terminates. All such amount shall be used and held by Landlord for payment
     of such obligations of Tenant hereunder, with Tenant being liable for any
     additional costs therefor upon demand by Landlord, or with any excess to be
     returned to Tenant after all such obligations have been determined and
     satisfied, as the case may be.

     G.   If any clause or provision of this Lease is illegal, invalid or
     unenforceable under present or future laws effective during the Term of
     this Lease, then and in that event, it is the intention of the parties
     hereto that the remainder of this Lease shall not be affected thereby, and
     it is also the intention of the parties to this Lease that in lieu of each
     clause or provision of this Lease that is illegal, invalid or
     unenforceable, there be added as part of this Lease contract a clause or
     provision as similar in terms to such illegal, invalid or unenforceable
     clause or provision as may be possible and be legal, valid and enforceable.

     H.   Because the Premises are on the open market and are presently being
     shown, this Lease shall be treated as an offer with the Premises being
     subject to prior Lease and such offer subject to withdrawal or
     non-acceptance by Landlord or to other use of the Premises without notice,
     and this Lease shall not be valid or binding unless and until accepted by
     Landlord in writing and a fully executed copy delivered to both parties
     hereto.

     I.   All references in this Lease to "the date hereof" or similar
     references shall be deemed to refer to the last date, in point of time, on
     which all parties hereto have executed this Lease.

26.  LIABILITY OF LANDLORD. Tenant agrees that no trustee, officer, employee,
     agent or individual partner of Landlord, or its constituent entitles,
     shall be personally liable for any obligation of Landlord hereunder, and
     that Tenant must look solely to the interests of Landlord, or its
     constituent entities in the subject real estate, for the enforcement of
     any claims against Landlord arising hereunder.

27.  ADDITIONAL PROVISIONS. Addendum and additional paragraphs attached hereto
     and made a part hereof.



     LANDLORD:                               TENANT:

     ISSAQUAH #1 LIMITED PARTNERSHIP         BAXTER HEALTHCARE CORPORATION
     a Texas limited partnership             a Delaware corporation


     By: /s/ [SIG]                           By: /s/ [SIG]               [J8/30]
         --------------------------------        -------------------------------
                                             Title: Vice President
                                                    ----------------------------
<PAGE>   10

STATE OF ILLINOIS             )
                              ) SS.
County of Lake                )


     BE IT REMEMBERED, That on this 30th day of August, 1988, before me, the
undersigned a Notary Public in and for said County and State, personally
appeared the within named A.F. Stanbitz known to me to be Vice President who
executed the within instrument and acknowledged to me that he executed the same
freely and voluntarily.

                  IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed
                           my official seal the day and year last above written.

                                         [MARILYN L. TALLMAN] 
                                         --------------------------------------
                                         Notary Public for State of Illinois
                                         My commission expires October 30, 1988



STATE OF WA                   )
                              ) SS.
County of King                )


     BE IT REMEMBERED, That on this 24th day of Oct, 1988, before me, the
undersigned a Notary Public in and for said County and State, personally
appeared the within named Curtis Feeny known to me to be general partner who
executed the within instrument and acknowledged to me that he executed the same
freely and voluntarily.

                  IN TESTIMONY WHEREOF, I have hereunto set my hand and affixed
                           my official seal the day and year last above written.

                                         [SIG ILLEGIBLE] 
                                         --------------------------------------
                                         Notary Public for State of WA
                                         My commission expires 7/90



<PAGE>   11
ADDENDUM TO LEASE AGREEMENT:

                         ISSAQUAH #1 LIMITED PARTNERSHIP
                           a Texas limited partnership

                                       and

                          BAXTER HEALTHCARE CORPORATION
                             a Delaware corporation



Additional Paragraph 28, Landlord's Consent. Whenever a clause of this lease
requires Landlord's consent or approval, the Landlord expressly covenants and
agrees not to withhold or delay his consent unreasonably.



Additional Paragraph 29, Options to Renew. Provided Tenant is not, and has not
been, in default of any of its obligations under this Lease, it shall have three
(3) options to renew this Lease for the Premises in "as-is" condition for a term
of five (5) years each on the same terms and conditions as set forth in this
Lease except that the monthly base rent during the first option period will be
$48,796.00. The monthly base rent for the second and third option periods shall
be at current market rent, as determined by Landlord. In no event will the
monthly rental be less than the rental for the last month of the previous term.

To exercise the first option period, Tenant shall give Landlord written notice
to exercise its option at least 180 days prior to the expiration of the current
lease term.

To exercise the second and third option terms, Tenant shall give Landlord
written notice to exercise its options at least 180 days prior to the expiration
of the then current lease term. Within 15 days after Tenant exercises its option
to renew, Landlord will provide Tenant with the current market rent for the
first five years of the renewal term. Tenant shall have 45 days from
notification by Landlord of renewal rent to accept Landlord's market rent. If
Tenant does not accept Landlord's rental figure within the 45 day period, this
option shall be null and void. Landlord shall have no further obligation to
Tenant and Landlord may enter into leases with a third party.

Notwithstanding anything to the contrary herein contained, Tenant's right to
extend the term by exercise of any of the foregoing options shall be conditioned
upon the following: (i) at the time of the exercise of the option, and at the
time of the commencement of any such extended term, Tenant shall be in
possession of and occupying the Premises for the conduct of its business therein
and the same shall not be occupied by any assignee, subtenant or licensee, the
option to extend being applicable hereunder only with respect to so much of the
Premises as is actually occupied by Tenant, and (ii) the notice of exercise
shall constitute a representation by Tenant to Landlord effective as of the date
of the exercise and as of the date of commencement of the extended term, that
Tenant does not intend to seek to assign the Lease in whole or in part, or
sublet all or any portion of the Premises, the election to extend the term being
for purposes of utilizing the Premises for Tenant's purposes in the conduct of
Tenant's business therein.




<PAGE>   12
Additional Paragraph 30. Option to Expand/First Right of Refusal. For a period
of twelve (12) months after the Commencement Date of this Lease, Landlord hereby
reserves for expansion by Tenant the approximate 4,000 square feet adjacent to
the Premises and outlined in green on Exhibit C attached.

If Tenant has not exercised its option to expand, then after the initial twelve
month period of the Lease, Tenant shall have a first right of refusal for the
approximate 4,000 square feet adjacent to the Premises and outlined in green on
Exhibit C attached. Upon notification of Landlord to Tenant, verbally or in
writing, Tenant shall have five (5) working days to notify Landlord of Tenant's
desire to exercise Tenant's right of first refusal, on the same terms and
conditions as the offer to lease that Landlord has received. In the event Tenant
fails to give Landlord notice of Tenant's election to lease the adjoining space
within the time period, Tenant shall have no further right, title or interest in
the adjacent space and the right of first refusal shall terminate. If on the
other hand Tenant exercises its right of first refusal in the manner provided
above, Tenant shall immediately deliver to Landlord payment for the first
month's rent and security deposit for the adjacent space (in the same manner as
provided for in this Lease), and the lease of the adjacent property shall be
consummated without delay, in accordance with the terms set forth in the lease
offer.

Additional Paragraph 31. Holdover Rent February and March, 1989. Landlord shall
pay to Tenant an amount equal to the Holdover Rent, if any, which exceeds
Tenants current rent, as of January 1, 1989, for their current location by 110%,
for the months of February and March, 1989. That is, the Tenant will pay up to
110% of their current rental amount, as of January 1, 1989, for the months of
February and March 1989 and Landlord will pay the Holdover Rent above that
amount. The Holdover Rent shall be verified by delivery, by Tenant to Landlord,
of the holdover lease agreement. All holdover provisions negotiated by Tenant
with its current landlord are subject to Landlord's (Issaquah #1) approval.

Additional Paragraph 32. Additional Provisions for Paragraph 1C. Date of
Delivery of Premises. Landlord shall use all reasonable efforts to have the
Premises completed and ready for occupancy on or before April 1, 1989.

In the event that the Premises are not Substantially Completed by April 1, 1989,
as defined in Paragraph IC of the Lease, the Landlord shall pay to Tenant an
amount equal to the Holdover Rent. The "Holdover Rent" is defined as the
difference between the normal monthly rent that Tenant is currently paying as of
January 1, 1989 and the rent Tenant is paying as of April 1, 1989. The Holdover
Rent shall be verified by delivery, by Tenant to Landlord, of the holdover lease
agreement. All holdover provisions negotiated by Tenant with its current
landlord are subject to Landlord's (Issaquah #1) approval.

For every month after April 1989 that the Premises are not Substantially
Complete as defined in Paragraph 1C, Landlord shall pay to Tenant the Holdover
Rent as described in the above paragraph. The first day of every month or the
date required for rent payment in the holdover agreement, whichever is later,
shall be the reference date for the month when determining Substantial
Completion.



<PAGE>   13
If Landlord has not Substantially Completed the Premises by September 1, 1989,
then Tenant shall have the right to cancel this Lease by written notice to
Landlord delivered on September 1, 1989. Such cancellation right shall continue
for a period of five (5) working days, then such termination option shall be
null and void. Neither party shall have any further liability to the other party
upon termination.

Notwithstanding anything to the contrary contained in the Lease, the Landlord
shall have no liability to the Tenant hereunder if prevented from achieving the
aforementioned deadlines by reason of (a) any strike, lock-out or other labor
troubles, (b) interruption or availability of electrical power, gas, water, fuel
oil, or other utility or service, (d) riot, war, insurrection or other national
or local emergency, (e) accident, flood, fire or other casualty (f) adverse
weather condition, (g) other acts of God, (h) inability to obtain a building
permit or a certificate of occupancy, or (i) other cause similar or dissimilar
to any of the foregoing and beyond the Landlord's reasonable control. In such
event, (a) the Commencement Date shall be postponed for a period equaling the
length of such delay, (b) the Termination Date shall be determined pursuant to
the provisions of Paragraph 1 by reference to the Commencement Date as so
postponed, (c) The April 1, 1989 and September 1, 1989 deadline dates detailed
above shall be postponed for a period equaling the length of such delay.

Tenant's obligation to commence the payment set forth in the Lease shall not be
affected or deferred and Landlord shall have no liability to the Tenant
hereunder if Landlord shall be delayed in Substantially Completing the Premises
as a result of any one or more of the following:

        (i) Tenant's alterations or additions to Exhibit C and/or Exhibit C-1;

        (ii) Tenant having not approved the working drawing plans by September
30, 1988;

        (iii) Such other acts or omissions by Tenant, or Tenant's agents that
delay completion of the Tenant Improvements.

For each day that Landlord is delayed in Substantially Completing the Premises
due to i) through iii) above, the April 1, 1989 and September 1, 1989 deadline
dates shall be delayed by the same number of days, and the Commencement date
shall be moved forward by the same number of days.

Additional Paragraph 33. Direct Cost Reimbursement. Landlord agrees to reimburse
Tenant for Tenant's direct costs resulting from Landlord's failure to have the
Premises Substantially Complete by April 1, 1989 but not to exceed the sum of
One Thousand Dollars ($1,000.00).

<PAGE>   14
                               AMENDMENT TO LEASE


THIS AMENDMENT TO LEASE is made this 21st day of August, 1990, by and between
Issaquah #1 Limited Partnership, a Texas limited partnership (the "Landlord")
and Baxter Healthcare Corporation, a Delaware corporation (the "Tenant").

          WHEREAS, Landlord and Tenant entered into a Lease Agreement dated
August 22, 1988 (the "Lease"), for Suite 107 located in Building B, I-90 Lake
Place (The "Premises"), as more fully described in the Lease; and

          WHEREAS, Tenant desires to lease an additional 3,626 square feet of
space adjacent to the Premises; and Landlord and Tenant desire to modify the
Lease accordingly;

          NOW, THEREFORE, in consideration of the covenants and agreements
contained herein, the parties hereby mutually agree as follows:

          1.   The Lease is hereby amended to reflect that effective October 1,
1990, the Premises shall be increased to approximately 47,825 square feet as
outlined in red on Exhibit A-1 attached hereto, which shall replace and
supersede Exhibit A to the Lease.

          2.   Effective October 1, 1990, the monthly rent as provided for in
Paragraph 2 of the Lease shall be increased to Forty Three Thousand Nine
Hundred Ninety Nine and no/100 Dollars ($43,999.00).

          3.   Landlord shall at its sole cost and expense perform tenant
improvements upon the Premises within an allowance of $54,390.00 including
permits, fees and Washington State Sales Tax.

          4.   In the event any payment due from Tenant to Landlord is made by
a party other than Tenant, such payment shall be deemed to have been made by
and for the account of Tenant, and the party making such payment shall have no
rights under this Lease.

          5.   No trustee, officer, employee, agent, or individual partner of
Landlord, or its constituent entities, shall be personally liable for any
obligation of Landlord hereunder, and Tenant must look solely to the interests
of Landlord, or its constituent entitles in the subject real estate, for the
enforcement of any claims against Landlord arising hereunder.

          6.   Tenant warrants that all necessary corporate actions have been
duly taken to permit Tenant to enter into this Amendment to Lease and that each
undersigned officer has been duly authorized and instructed to execute this
Amendment to Lease.

          7.   Except as expressly modified above, all terms and conditions of
the Lease remain in full force and effect and are hereby ratified and confirmed.


LANDLORD:                               TENANT:

Issaquah #1 Limited Partnership         Baxter Healthcare Corporation,
a Texas limited partnership             a Delaware corporation

   By:  Crow-Seattle #1, Inc., a
        Texas corporation
        its General Partner


        By:  /s/  CURTIS FEENY          By:  /s/  [SIG]
           -----------------------         ---------------------------
           Curtis Feeny, President         Its: Director Corporate Real
                                           Estate
<PAGE>   15
STATE OF ILLINOIS       )
                        ) SS.
COUNTY OF LAKE          )

          BE IT REMEMBERED, That on this 3rd day of October, 1990, before me,
the undersigned a Notary Public in and for said County and State, personally
appeared the within named [ILLEGIBLE] known to me to be Director of Corporate
Real Estate who executed the within Instrument and acknowledged to me that he
executed the same freely and voluntarily.

                              IN TESTIMONY WHEREOF, I have hereunto set my hand
                              and affixed my official seal the day and year
                              last above written.

                              /s/ RACHEL G. HINSHELWOOD
                              -------------------------------------------------
[OFFICIAL SEAL]
                              Notary Public for the State of Illinois

                              My commission expires 4/15/91


STATE OF WASHINGTON     )
                        ) SS.
COUNTY OF KING          )


          On this 18th day of October, 1990, before me, the undersigned, a
Notary Public in and for the State of Washington, duly commissioned and sworn,
personally appeared Curtis Feeny, to me known to be the person who signed as
President of Crow-Seattle #1, Inc., General Partner of Issaquah #1 Limited
Partnership, the Partnership that executed the within and foregoing Instrument,
and acknowledged said Instrument to be the free and voluntary act and deed of
Crow-Seattle #1, Inc. for the uses and purposes therein mentioned; and on oath
stated that he was authorized to execute the said Instrument on behalf on said
Crow-Seattle #1, Inc. and that the corporation was authorized to execute said
Instrument on behalf of Issaquah #1 Limited Partnership.

          IN WITNESS WHEREOF I have hereunto set my hand and official seal the
day and year first above written.

                                        /s/ [SIG]
                                        --------------------------------------
                                        NOTARY PUBLIC in and for the State of
                                        Washington, residing at [ILLEGIBLE]
                                        My appointment Expires 4/26/92.

<PAGE>   16
                                                         BASIC LEASE INFORMATION


               Lease Date:              August 22, 1988

               Landlord:  Issaquah #1 Limited Partnership, a Texas limited
                          partnership

               Address of Landlord:     300 120th Avenue N.E.
                                        Building 1
                                        Suite 120
                                        Bellevue, Washington  98005

               Tenant:  BAXTER HEALTHCARE CORPORATION, a Delaware Corporation

               Premises:                I-90 Lake Place
                                        2005 N.W. Sammamish Road
                                        Building B, Suite 107
                                        Issaquah, Washington  98027

PARAGRAPH 1    "Premises" approximately 43,133 square feet in Building B of
               approximately 54,600 square feet (computed from measurements to
               the exterior of outside walls of the building and to the center
               of interior walls), such premises being shown and outlined in red
               on the plan attached hereto as Exhibit A, and being part of the
               real property described in Exhibit B attached hereto.

PARAGRAPH 1    Lease Term: Commencing on the "Commencement Date" as hereinafter
               defined and ending 60 months thereafter except that in the event
               the Commencement Date is a date other than the first day of a
               calendar month, said term shall extend for said number of months
               in addition to the remainder of the calendar month following the
               Commencement Date.

PARAGRAPH 1    Scheduled Term Commencement Date:                  April 1, 1989*
               * Revised to Sept 1st, 1989 per Nov 16th
               letter. ______                                          6/28/90

PARAGRAPH 2    Monthly Base Rent:                                   $39,683.00

PARAGRAPH 2B   Security Deposit:      $0.00

               Tenant's Initial Monthly Escrow Payment for Taxes
               and Other Charges:

PARAGRAPH 7    Tenant's Initial Monthly Common Area Maintenance
               Charge:                                              $1,294.00

PARAGRAPH 13B  Tenant's Initial Monthly Insurance Escrow Payment:     $432.00

               Tenant's Initial Monthly Payment Total:              41,409.00

               The foregoing Basic Lease Information is hereby incorporated into
               and made a part of this Lease. Each reference in this Lease to
               any of the Basic Lease Information shall mean the respective
               information herein above set forth and shall be construed to
               incorporate all of the terms provided under the particular Lease
               paragraph pertaining to such information. In the event of any
               conflict between any Basic Lease Information and the Lease, the
               former shall control.
<PAGE>   17
                            THIRD AMENDMENT TO LEASE

THIS AMENDMENT TO LEASE is made this 21st day of March 1994, by and between
Department of Natural Resources, Successor in Interest to Issaquah #1 Limited
Partnership, a Texas Limited Partnership, Successor in Interest to Crow-Seattle
#1, a Texas corporation, (the "Landlord") and Baxter Diagnostics, Inc., a
Delaware Corporation (the "Tenant").

     WHEREAS, Landlord and Tenant entered into a Lease Agreement dated August
22, 1988, as amended August 13, 1990 and August 21, 1990 (the "Lease"), for
Suite 107 located in Building B, 2005 NW Sammamish Road (the "Premises"), as
more fully described in the Lease; and

     WHEREAS, Tenant desires to reduce the square footage of the Premises; and

     WHEREAS, the current term of the Lease expires August 31, 1994, and 
Landlord and Tenant desire to extend the term of the Lease, and to modify the
Lease accordingly;

     NOW, THEREFORE, in consideration of the covenants and agreements contained
herein, the parties hereby mutually agree as follows:


     1.   The term of the Lease is hereby extended for a period of sixty (60)
months commencing September 1, 1994, and terminating August 31, 1999.

     2.   Effective September 1, 1994, the Premises shall be reduced from
approximately 47,825 square feet to approximately 35,935 square feet as outlined
in red on Exhibit A-2 attached hereto, which shall replace and supersede
Exhibit A-1 to the Lease provided, however, that an acceptable lease has been
fully executed between Landlord and Bartels Prognostics, Inc., ("Prognostics")
prior to August 31, 1994. The Premises shall include approximately 572 square
feet of common area corridor and restrooms as shown on Exhibit A-2.

     3.   Effective September 1, 1994, the Monthly Rate Rent as provided for in
Paragraph 2 of the Lease shall be reduced to Third-two Thousand One Hundred
Ninety One and 99/100 Dollars ($32,191.77), which is the equivalent of $10.75
per square foot per year, triple net. Effective September 1,1997, the Monthly
Base Rent as provided for in Paragraph 2 of the Lease shall be Thirty-three
Thousand Six Hundred Eighty Nine and 06/100 Dollars ($33,689.06), which is the
equivalent of $11.25 per square foot per year, triple net.

     4.   If a lease between Prognostics and Landlord is not consummated prior
to August 31, 1994, or if a lease with Prognostics is consummated prior to
August 31, 1994 but terminates for any reason during the term of this Lease
extended hereunder and Prognostics vacates the Premises ("Prognostics
Termination"), then effective August 31, 1994 or upon termination of the
Prognostics Lease Tenant hereby agrees that the Premises shall be increased to
approximately 39,043 square feet as outlined on Exhibit A-3 attached hereto
which shall replace and supersede Exhibit A-2 previously referenced herein. The
Premises shall include approximately 563 square feet of common area corridor and
restrooms as shown on Exhibit A-3.


  
<PAGE>   18
     5.    If the Premises are increased pursuant to conditions described in
Paragraph 4 above, then the Monthly Base Rent as provided for in Paragraph 2 of
the Lease shall be increased based upon the equivalent Monthly Base Rent per
square foot per year, triple net as set forth in Paragraph 3 above.

     6.   Tenant agrees to extend the term as referenced above and accept the
Premises in as-is condition. If a lease with Prognostics is not consummated
prior to August 31, 1994, or if a lease with Prognostics is consummated prior to
August 31, 1994 but that Prognostics lease terminates for any reason thereafter,
Landlord shall have the right to perform certain tenant improvements, at
Landlord's expense and at Landlord's sole discretion as required to separate the
Premises from "Northwing Space" and "Eastwing Space" as outlined on Exhibit A-3
and said work shall interfere with Tenant's operations as little as possible.

          Separating the space may include but is not limited to constructing
tenant demising walls, modifying electrical and HVAC systems to provide separate
service as is determined by Landlord to be reasonably feasible. Landlord and
Tenant agree to use best efforts to facilitate the separation of the Northwing
and Eastwing from the Premises in a timely and efficient manner.

     7.   If Prognostics leases space then Tenant shall allow Prognostics free
and unrestricted access to the following common areas:

          1.  Second Floor Restrooms    4.  Central Staircase
          2.  Hallways & Corridors      5.  First Floor Main
                on Second Floor               Building Entry  
          3.  Elevator                  6.  First Floor Restrooms and Common 
                                              Corridors located at North Wing

Tenant agrees to indemnify, defend and hold Landlord harmless from and against
any claims, liabilities or damages (including attorneys fees and costs) relating
to Prognostics use of these areas, unless caused by Landlord's gross negligence
or willful misconduct.

     8.   Paragraph 5D of the Lease shall be deleted and replaced with the
following:

          Landlord shall enter into a regularly scheduled normal preventative
maintenance agreement/service contract with a mutually agreeable maintenance
contractor ("Service Contractor") for the servicing of all heating,
air-conditioning and exhaust systems and equipment (including but not limited to
the hydronic heat pump system, roof top gas pack HVAC units, gas fired space
heaters and equipment and other exhaust fans: collectively referred to as
"Building Air Systems") serving the Premises, the Northwing Space and the
Eastwing Space. Tenant shall be responsible for (a) its Proportionate Share or
directly attributable costs of such Service Agreement as reasonably determined
by Landlord and (b) its Proportionate Share or directly attributable costs of
repairs, replacements or other services related to the Building Air Systems as
reasonably determined by Landlord, which costs shall be included in the monthly
Common Area Maintenance Charge per Paragraph 7 of the Lease.

     9.   Paragraph 7 of the Lease "Monthly Common Area Maintenance Charge"
shall be amended to include the following:

          Tenant agrees to pay its proportionate share of the cost of
maintaining the corridor and


<PAGE>   19
restroom common area located between the Premises and Northwing space ("Common
Area North"), as shown on Exhibit A-2. Such costs shall include but are not
limited to janitorial service, and restroom supplies, repairs, light replacement
and those costs required to maintain the Common Area North in reasonably good
condition and repair.

     10.  Paragraph 11 of the Lease, "Utilities" shall be amended to add the
following:

          For the purposes of this Lease Agreement, electricity and/or gas
service shall be jointly metered with the Northwing (except for approximately
2,500 square feet located at the northend of the Northwing Space which is
currently separately metered for gas and electricity) and Eastwing spaces.

     11.  Landlord represents and warrants to the Tenant the following, which
will survive termination of the lease:

(a)  To the best of Landlord's actual knowledge, which knowledge is limited to
the report dated September 11, 1990 prepared by Dames & Moore, Inc., the
property is in compliance with all applicable Environmental Laws. "Environmental
Laws" means any federal, state or local law, rule, regulation or ordinance
relating to environmental, health or safety matters.

(b)  To the best of Landlord's actual knowledge, which knowledge is limited to
the knowledge of Rod Rennie, Project Manager, of State of Washington Department
of Natural Resources, subsequent to the Dames & Moore, Inc., report dated
September 11, 1990, Landlord has received no notice of any litigation,
investigation or proceeding pending or threatened against Landlord or the
property regarding the presence or Release of Hazardous Materials at the
property. "Hazardous Materials" means any substance or waste governed by any
Environmental Law.

(c)  To the best of Landlord's actual knowledge, which knowledge is limited to
the report dated September 11, 1990 prepared by Dames & Moore, Inc., the
property does not contain: any underground storage tanks or surface
impoundments; any asbestos or asbestos-containing material; any polychlorinated
biphenyls (PCBs); or Release or threatened Release of any Hazardous Materials,
nor are any Hazardous Wastes generated. Landlord will remove and/or encapsulate
any asbestos, at Landlord's expense, in the leased property if required to do so
by any federal, state, or local laws or regulations.

(d)  To the best of Landlord's actual knowledge, which knowledge is limited to
the knowledge of Rod Rennie, Project manager, subsequent to the Dames & Moore,
Inc., report dated September 11, 1990, the property is in compliance with all
applicable environmental laws.

(e)  If there is a Release of Hazardous Materials at the property that is caused
by landlord, Landlord will cleanup the Release in compliance with all applicable
Environmental laws. If there is a Release of Hazardous Materials at the property
that is not caused or permitted by Tenant, Landlord will indemnify Tenant for
any cleanup, litigation or penalties incurred.

(f)  If Landlord breaches any environmental provision in this agreement which
interferes with Tenant's use of the property, Tenant may terminate this Lease
unless Landlord remedies the condition within a reasonable time.


<PAGE>   20
Tenant represents and warrants to the Landlord the following, which will
survive termination of this lease:

(a)   If there is a Release of Hazardous Materials at the property caused or
      permitted by Tenant, Tenant will clean up the Release in compliance with
      all applicable Environmental Law.

(b)   Tenant will use the leased property in compliance with all applicable
      Environmental Laws.

      12.   Additional Paragraphs 29, 30, 31, 32, and 33 of the original Lease
dated August 22, 1988, shall be of no further force or effect.

      13.   In the event any payment due from Tenant to Landlord is made by a
party other than Tenant, such payment shall be deemed to have been made by and
for the account of Tenant, and the party making such payment shall have no
rights under this Lease.

      14.   No trustee, officer, employee, agent, or individual partner of
Landlord, or its constituent entities, shall be personally liable for any
obligation of Landlord hereunder, and Tenant must look solely to the interests
of Landlord, or its constituent entities in the subject real estate, for the
enforcement of any claims against Landlord arising hereunder.

      15.   Tenant warrants that all necessary corporate actions have been duly
taken to permit Tenant to enter into this Amendment to Lease and that each
undersigned officer has been duly authorized and instructed to execute this
Amendment to Lease.

      16.   Except as expressly modified above, all terms and conditions of the
Lease remain in full force and effect and are hereby ratified and confirmed.

LANDLORD:                               TENANT:

State of Washington Department of       Baxter Diagnostics, Inc.,
Natural Resources, Successor in         a Delaware Corporation
Interest to Crow Seattle #1 Limited
Partnership, a Texas Limited
Partnership, Successor in Interest
to Crow Seattle #1, A Texas
corporation


By: /s/  RICK CASPER                    By: /s/ [SIG]
   -------------------------------         -----------------------------------

Its: Real Estate Division Manager       Its: Vice President


Approved as to form only this 3rd
day of May, 1994, by the Washington
State Attorney General's Office,
Jim Schwartz, Assistant Attorney
General.
  
<PAGE>   21
STATE OF ILLINOIS        )
                         ) SS.
County of Lake           )

          BE IT REMEMBERED, That on this 14th day of April, 1994, before me,
the undersigned a Notary Public in and for said County and State, personally
appeared the within named [SIG] known to me to be Vice President who
executed the within Instrument and acknowledged to me that he executed the same
freely and voluntarily.

                              IN TESTIMONY WHEREOF, I have hereunto set my hand
                              and affixed my official seal the day and year
                              last above written.

                               /s/ RACHEL G. HINSHELWOOD
                              -----------------------------------------------
[OFFICIAL SEAL]
                              Notary Public for the State of Illinois

                              My commission expires 4/15/95



STATE OF WASHINGTON      )
                         ) SS.
County of THURSTON       )


          On this 6th day of May, 1994, before me, the undersigned a Notary
Public in and for the State of Washington, duly commissioned and sworn,
personally appeared Rick Cooper, to me known to be the person who signed as
Agent of the Department of Natural Resources that executed the within and
foregoing instrument, and acknowledged said instrument to be the free and
voluntary act and deed of the Department of Natural Resources for the uses and
purposes therein mentioned; and on oath stated that ______ was authorized to
execute the said instrument on behalf of said Department of Natural Resources.

          IN WITNESS WHEREOF I have hereunto set my hand and official seal the
day and year first above written.

                                        /s/ STEVEN R. CARLSON
                                        ---------------------------------------
[NOTARY SEAL]                           NOTARY PUBLIC in and for the State of
                                        Washington, residing at Olympia
                                        My appointment Expires 9/30/95