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                                                                   EXHIBIT 10.66


                               SECURITY AGREEMENT


               This Security Agreement ("Agreement") made as of August 18, 1997
by ACCUMED INTERNATIONAL, INC., a Delaware corporation ("Debtor"), with its
principal place of business at 900 North Franklin Street, Suite 401, Chicago,
Illinois 60610, in favor of ROBERT L. PRIDDY, an individual ("Secured Party")
having an address at 3435 Kingsboro Road #1601, Atlanta, Georgia 30326.

               RECITAL: Debtor has executed a certain Promissory Note of even
date herewith made payable to Secured Party (as the same may be amended,
restated, supplemented or otherwise modified from time to time, the "Note"),
providing for the making of a $500,000 term loan to Debtor. It is a condition
precedent to the making of such loan that Debtor shall have granted the security
interest contemplated by this Agreement.

               1.     DEFINITIONS

               1.1 General Definitions. When used herein, the following terms
shall have the following meanings:

                      (a) "Account" shall mean, collectively, all accounts (as
               defined in the Code) arising from the sale of cytopathology
               instruments and software by the Debtor to Olympus America, Inc.,
               the balance of which as of the date hereof is $275,560.

                      (b) "Account Debtor" shall mean the party or parties who
               are obligated on or the Account.

                      (c) "Code" shall mean the Uniform Commercial Code as in
               effect in the State of Illinois from time to time.

                      (d) "Collateral" has the meaning specified in Section 2.1.

                      (e) "Default" shall mean the occurrence or existence of
               any "Event of Default" under (and as defined in) the Note.

                      (f) "Financing Agreements" shall mean the Note and all
               other agreements, instruments and documents executed by or on
               behalf of Debtor and delivered to Secured Party in connection
               therewith, including, without limitation, this Agreement.



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                      (g) "Liabilities" shall mean all liabilities, obligations
               and indebtedness of any and every kind and nature that arise
               under the Note, this Agreement or any other Financing Agreement,
               whether heretofore, now or hereafter owing, arising, due or
               payable from Debtor to Secured Party.

                      (h) "Lien" shall mean any mortgage, deed of trust, pledge,
               hypothecation, assignment, conditional sale agreement, deposit
               arrangement, security interest, encumbrance, lien (statutory or
               otherwise), preference, priority or other security agreement or
               preferential arrangement of any kind or nature whatsoever in
               respect of any property of a Person, whether granted voluntarily
               or imposed by law, and includes the interest of a lessor under a
               capitalized lease or under any financing lease having
               substantially the same economic effect as any of the foregoing
               and the filing of any financing statement or similar notice,
               under the Code or other comparable law of any jurisdiction.

                      (i) "Person" shall mean any individual, sole
               proprietorship, partnership, joint venture, trust, unincorporated
               organization, association, limited liability company,
               corporation, institution, entity, party, or government (whether
               national, federal, state, provincial, county, city, municipal or
               otherwise, including, without limitation, any instrumentality,
               division, agency, body or department thereof).

               1.2 Other Terms. All other terms contained in this Agreement,
where the context so indicates (unless otherwise specifically defined herein),
shall have the meanings provided by the Code to the extent the same are used or
defined therein.

               2.     COLLATERAL

               2.1 Security Interest. To secure payment and performance of
Debtor's Liabilities, Debtor hereby grants to Secured Party a continuing
security interest in and to the following property and interests in property:
all of Debtor's right, title and interest in the Account, and all proceeds of
the Account, together with all of Debtor's books and records relating to the
Account (the "Collateral").

               2.2 Financing Statements. Debtor will execute and deliver to
Secured Party such financing statements or amendments thereof or supplements
thereto, and such other instruments as Secured Party may from time to time
require in order to preserve, protect and maintain the security interest hereby
granted. Debtor further agrees that a carbon, photographic, photostatic or other
reproduction of this Agreement or of a financing statement is sufficient as a
financing statement.

               3.     REPRESENTATIONS, WARRANTIES AND COVENANTS



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               3.1 Representations and Warranties. Debtor hereby represents and
warrants to Secured Party that:

               (a) The Debtor (i) is a corporation duly organized, validly
        existing and in good standing under the laws of the State of Delaware,
        (ii) is duly qualified to do business as a foreign corporation and is in
        good standing under the laws of Illinois and each jurisdiction in which
        the nature of the Debtor's business or the ownership of property
        requires such qualification, and (iii) has all requisite corporate power
        and authority to own, operate and encumber its property and to conduct
        its business as presently conducted and as proposed to be conducted in
        connection with and following the consummation of the transactions
        contemplated by the Note and this Agreement.

               (b) The Debtor has the requisite corporate power and authority to
        execute, deliver and perform each of the Note, this Agreement and each
        document which is to be executed by it in connection with either of
        them. The execution, delivery, performance and filing, as the case may
        be, of each such document have been duly approved by the Executive
        Committee of the board of directors of the Debtor and such approval has
        not been rescinded. No other corporate action or proceedings on the part
        of the Debtor is necessary to consummate such transactions. Each of the
        Note, this Agreement and each document which is to be executed by the
        Debtor in connection with either of them has been duly executed and
        delivered by it and constitutes its legal, valid and binding obligation,
        enforceable against it in accordance with its terms, is in full force
        and effect.

               (c) The execution, delivery and performance of each of the Note,
        this Agreement and each document which is to be executed by the Debtor
        in connection with either of them do not and will not (i) conflict with
        the Debtor's certificate of incorporation or by-laws, (ii) any law known
        to the Debtor to be applicable to, or binding on, its business or the
        Collateral or any contractual restriction binding on or affecting the
        Debtor, or (iii) result in or require the creation or imposition of any
        Lien whatsoever upon any of the property or assets of the Debtor, other
        than Liens contemplated by the Note or this Agreement.

               (d) The Debtor is and will be the owner of, and has and will have
        good and marketable title to, the Collateral except for Collateral sold
        in the ordinary course of business. The Debtor is the legal and
        beneficial owner of the Collateral free and clear of any Lien or other
        interest of a third party, except for the security interest created by
        this Agreement and the Liens identified on Schedule A. No financing
        statement or other instrument similar in effect covering all or any part
        of the Collateral is on file in any recording office on the date hereof,
        except such as may have been filed in favor of (i) Secured Party and
        (ii) as set forth on Schedule A.

               (e) The office where Debtor keeps its records concerning the
        Collateral and Debtor's principal place of business and chief executive
        office are and will be located at the address(es) set forth on Schedule
        B attached hereto and made a part hereof. All of



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        Debtor's other places of business and all other places where Collateral
        is kept are located at the addresses set forth on Schedule B. The amount
        represented by the Debtor from time to time to Secured Party as the
        amount owing by each account debtor in respect of the Account will, at
        such time, be the correct amount actually and unconditionally owing by
        such account debtor(s) thereunder to the best of the Debtor's knowledge
        (except to the extent, if any, that such account debtor(s) may be
        entitled to normal trade discounts, adjustments, returns and
        allowances).

               (f) The correct corporate name of the Debtor on the date hereof
        is AccuMed International, Inc. and the Debtor will not use any other
        corporate or fictitious name other than AccuMed, Alamar and Sensititre.
        The Debtor will not change its name, identity or structure in any manner
        without the prior written consent of the Secured Party which shall not
        be unreasonably withheld, provided, that, as a condition to the
        effectiveness of any such consent, the Debtor shall execute and deliver
        to the Secured Party, at the Debtor's expense, any financing statements
        or other documents requested by the Secured Party reasonably necessary
        or desirable to maintain the validity, perfection and priority of the
        Liens intended to be created hereby.

               (g) This Agreement, together with the filing of a financing
        statement with the offices of the Secretary of State of Illinois, the
        Secretary of State of Michigan, the Secretary of State of Wisconsin and
        the Secretary of State of Ohio and the County Recorder of Cuyahoga
        County, Ohio, upon the giving of value to the Debtor by Secured Party,
        creates a valid and perfected security interest in the Collateral (other
        than Collateral in which a security interest may not be perfected by
        filing a financing statement under the Code and the Uniform Commercial
        Code as in effect in the States of Michigan, Ohio and Wisconsin),
        securing the payment of the Secured Obligations.

               (h) No consent of any other person or entity and no
        authorization, approval or other action by, and no notice to or filing
        with, any governmental authority is required (i) for the grant by the
        Debtor of the security interest granted hereby or for the execution,
        delivery or performance of this Agreement by the Debtor, (ii) for the
        perfection or, except for the filing of the appropriate continuation
        statements with respect to the financing statements described in clause
        (g) above, maintenance of the security interest created hereby
        (including the maintenance of the relative priority of such security
        interest) or (iii) for the exercise by Secured Party of its rights and
        remedies hereunder.

               (i) There are no conditions precedent to the effectiveness of
        this Agreement that have not been satisfied or waived in writing.

               3.2 Covenants. Until performance, payment and/or satisfaction, in
full, of the Liabilities, Debtor covenants and agrees as follows:

               (a) Debtor will at all times keep accurate and complete records
        and books of account with respect to all of Debtor's business
        activities, in accordance with sound



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        accounting practices and generally accepted accounting principles. Such
        records and accounts will be maintained at the address of Debtor set
        forth at the beginning of this Agreement.

               (b) Secured Party, or any Person designated by it, shall have the
        right, from time to time and upon reasonable notice, to call at Debtor's
        place or places of business during reasonable business hours, and,
        without hindrance or delay, to inspect, audit, check and make extracts
        from Debtor's books, records, journals, orders, receipts and any
        correspondence and other data relating to Debtor's business or to any
        transactions between the parties hereto, and shall have the right to
        make such verification concerning the Collateral as Secured Party may
        consider reasonable under the circumstances, all at Debtor's expense.
        Debtor will furnish to Secured Party such information relevant to the
        Collateral as Secured Party may from time to time reasonably request,
        including, without limitation, the original delivery or other receipts
        and duplicate invoices relating to the Account.

               4.     SALES, COLLECTIONS AND REPORTS

               4.1 Collection of Account. Debtor may collect the Account, but
only in the ordinary course of its business and only until such time, upon or
after the occurrence of a Default, as such privilege is revoked, in whole or in
part, by Secured Party's notification to Account Debtors to make payments
directly to Secured Party. Debtor will take such action with respect to the
collection of the Account and of the proceeds thereof, as Secured Party may
request.

               4.2 Notification of Account Debtors. Secured Party shall have the
right, at any time or times after the occurrence of a Default and while it is
continuing, to notify all applicable Account Debtors that the Account has been
assigned to Secured Party and that Secured Party has a security interest
therein; to direct all such Account Debtors to make payments to Secured Party of
all or any part of the sums owing Debtor by such Account Debtors; to enforce
collection of any of the Account by suit or otherwise; to surrender, release or
exchange all or any part of the Account; or to compromise, settle, extend or
renew for any period (whether or not longer than the original period) any
indebtedness thereunder or evidenced thereby.

               4.3 Endorsement by Secured Party. Debtor hereby authorizes
Secured Party to indorse, in the name of Debtor, any item, howsoever received by
Secured Party, representing payment on or other proceeds of any of the
Collateral.

               4.4 Other Collateral Issues. Debtor will deliver to Secured
Party, at such times and in such form as shall reasonably be designated by
Secured Party, assignments, schedules and reports relating to the Collateral.
Upon request by Secured Party, Debtor will mark its books and records to reflect
the security interest of Secured Party in the Account.



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               4.5 Return of Goods. Debtor shall promptly report to Secured
Party the return or repossession of any goods, the sale or lease of which shall
have given rise to the Account.
Secured Party shall have a security interest in all such goods.

               5.     DEFAULT; REMEDIES

               5.1 Remedies. In the event a Default shall occur and while it is
continuing:

               (a) All Liabilities may (notwithstanding any provisions thereof),
        at the option of Secured Party, and without demand, notice or legal
        process of any kind, be declared, and immediately shall become, due and
        payable, and Secured Party may exercise from time to time any rights and
        remedies available to it under applicable laws or in equity, including,
        without limitation, the Code, in addition to, and not in lieu of, any
        rights and remedies expressly granted in this Agreement, in any of the
        other Financing Agreements, or otherwise, all of which remedies shall be
        cumulative.

               (b) Without notice, demand or legal process of any kind, Secured
        Party, its nominee, designee or agent may take possession of any or all
        of the Collateral (in addition to Collateral of which it may already
        have possession), wherever it may be found, and for that purpose may
        pursue the same wherever it may be found, and may, without a breach of
        the peace, enter onto any of Debtor's premises ("Premises") where any of
        the Collateral is or may be located, and search for, and take possession
        of, any or all of the Collateral until the same shall be sold or
        otherwise disposed of. Secured Party, its nominee, designee or agent
        shall have the right to remove any or all of the Collateral from the
        Premises and/or to assemble and store the Collateral on the Premises,
        and otherwise to operate, occupy and use the Premises, in connection
        with public or private sales of the Collateral, all without cost to
        Secured Party, its nominee, designee or agent.

               (c) At Secured Party's request, Debtor will, at Debtor's expense,
        assemble the Collateral at one or more places, reasonably convenient to
        both parties, where the Collateral may, at Secured Party's option,
        remain, at Debtor's expense, pending sale or other disposition thereof.

               (d) Debtor acknowledges that any breach by Debtor of any of the
        provisions of this Section 5.1 will cause irreparable injury to Secured
        Party, and that there is not adequate remedy at law for a breach of the
        provisions of such Section. Debtor agrees that Secured Party will have
        the immediate right, upon such breach, to obtain injunctive and other
        equitable relief in any court of competent jurisdiction without any
        requirement of notice, and that the granting of any such relief shall
        not preclude Secured Party from pursuing any other available relief or
        remedies for such breach.

               5.2 Sale of Collateral. Any notification required by law of
intended sale, lease or other disposition by or on behalf of Secured Party of
any of the Collateral shall be deemed reasonably and properly given if mailed,
postage prepaid, to Debtor at Debtor's address set forth



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at the beginning of this Agreement, at least ten (10) calendar days before such
sale, lease or other disposition. Notice sent in such manner shall be deemed
received on the fifth business day following the day of deposit in the mails.
Any proceeds of any sale, lease or other disposition by Secured Party of any of
the Collateral may be applied by Secured Party to the payment of expenses in
connection with the Collateral, including, without limitation, reasonable
"attorneys' fees" (as defined in Section 5.3 below) and legal expenses. Any
balance of such proceeds may be applied by Secured Party toward the payment of
the Liabilities in the manner set forth in Section 7.5 below. Debtor shall
remain liable for any deficiency, and Secured Party shall account for any
surplus.

               5.3 Attorneys' Fees; Costs and Expenses. As used in this
Agreement, "attorneys' fees" shall be defined as the reasonable value of the
services of the attorneys employed by Secured Party, from time to time, to
commence, defend or intervene in any court proceeding, or to file a petition,
complaint, answer, motion or other pleadings, or to take any other action in or
with respect to any suit or proceeding (bankruptcy or otherwise) relating to the
Collateral, this Agreement, the Note, or any of the other Financing Agreements,
or to protect, collect, lease, sell, take possession of, or liquidate any of the
Collateral or to attempt to enforce any security interest in any of the
Collateral, or to enforce any rights of Secured Party to collect any of the
Liabilities. Such attorneys' fees, and any expenses, costs and charges relating
thereto, including, without limitation, all fees of all paralegals and other
staff employed by such attorneys, and all other costs and expenses incurred by
Secured Party with respect to the enforcement, collection or protection of its
interests in the Collateral shall be repayable by Debtor to Secured Party on
demand, shall be additional Liabilities and shall be secured by the Collateral.

               5.4 Waiver of Bonds. IN THE EVENT SECURED PARTY SEEKS TO TAKE
POSSESSION OF ANY OR ALL OF THE COLLATERAL BY COURT PROCESS, TO OBTAIN ANY
INJUNCTION OR OTHER EQUITABLE RELIEF REQUIRING DEBTOR TO COMPLY WITH ANY OR ALL
OF THE TERMS AND PROVISIONS OF THIS AGREEMENT, INCLUDING, WITHOUT LIMITATION,
SECTION 5.1 ABOVE, OR OTHERWISE TO COMPLY WITH APPLICABLE LAW, DEBTOR HEREBY
IRREVOCABLY WAIVES ANY BONDS AND ANY SURETY THEREON OR SECURITY RELATING THERETO
WHICH IS REQUIRED OR ALLOWED BY ANY STATUTE, COURT RULE OR OTHERWISE AS AN
INCIDENT TO SUCH POSSESSION OR INJUNCTION, AND WAIVES ANY DEMAND FOR POSSESSION
PRIOR TO THE COMMENCEMENT OF ANY SUIT OR ACTION TO RECOVER WITH RESPECT THERETO.

               5.5 Waiver of Demand. Demand, presentment, protest and notice of
nonpayment is hereby waived by Debtor. Debtor also waives the benefit of all
valuation, appraisement and exemption laws.

               5.6 Waiver of Notice. IN THE EVENT OF A DEFAULT (PURSUANT TO
AUTHORITY GRANTED BY ITS BOARD OF DIRECTORS), DEBTOR HEREBY WAIVES



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ALL RIGHTS TO NOTICE AND HEARING OF ANY KIND PRIOR TO THE EXERCISE BY SECURED
PARTY OF ITS RIGHTS TO REPOSSESS THE COLLATERAL WITHOUT JUDICIAL PROCESS OR TO
REPLEVY, ATTACH OR LEVY UPON SUCH COLLATERAL WITHOUT PRIOR NOTICE OR HEARING,
EXCEPT AS EXPRESSLY PROVIDED IN SECTION 5.2. DEBTOR ACKNOWLEDGES THAT IT HAS
BEEN ADVISED BY COUNSEL WITH RESPECT TO THIS TRANSACTION AND THIS AGREEMENT.

               5.7 Grant of License. The Secured Party is hereby granted a
license and right to use, following the occurrence and during the continuance of
a Default, without payment of royalty or other compensation, the Borrower's
labels, patents, copyrights, rights of use of any name, trade secrets, trade
names, trademarks, service marks, customer lists and advertising matter, or any
property of a similar nature, as it pertains to the Collateral, in completing
production of, advertising for sale, and selling any Collateral.

               6.     TERM

               6.1 Term of Agreement. This Agreement shall continue in full
force and effect as long as any Liabilities are owing by Debtor to Secured
Party.

               6.2 Termination. No termination of this Agreement shall in any
way affect or impair the rights and liabilities of the parties hereto relating
to any transactions or events which occurred prior to such termination date or
to any Collateral in which Secured Party has a security interest. All
agreements, warranties and representations of Debtor shall survive such
termination.

               7.     MISCELLANEOUS

               7.1 Receipt of Payments. For purposes of determining the amount
of the Liabilities, including, without limitation, the computations of interest
which may from time to time be owing by Debtor to Secured Party, the receipt of
any check or any other item of payment by Secured Party shall not be treated as
a payment on account of the Liabilities until such check or other item of
payment is actually paid in collected funds. Any statement of account rendered
by Secured Party to Debtor relating to the Liabilities, including, without
limitation, all statements of balances owing, accrued interest, expenses and
costs, shall be presumed to be correct and accurate and constitute an account
stated unless, within thirty (30) days after receipt thereof by Debtor, Debtor
shall deliver to Secured Party written objection thereto specifying the error or
errors, if any, contained in any such statement.

               7.2 Successors and Assigns. Whenever in this Agreement there is
reference made to any of the parties hereto, such reference shall be deemed to
include, wherever applicable, a reference to the successors and assigns of such
party. The provisions of this Agreement shall be binding upon and shall inure to
the benefit of the successors and assigns of Debtor and Secured Party.



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               7.3 Survival of Representations. All representations and
warranties of Debtor, and all terms, provisions, conditions and agreements to be
performed by Debtor contained herein, and in any of the other Financing
Agreements shall be true and satisfied at the time of the execution of this
Agreement, and shall survive the closing hereof and the execution and delivery
of this Agreement.

               7.4 Governing Law; Severability. This Agreement shall be
construed in all respects in accordance with, and governed by, the laws and
decisions of the State of Illinois. Wherever possible each provision of this
Agreement shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Agreement shall be prohibited by or
invalid under applicable law, such provision shall be ineffective to the extent
of such prohibition or invalidity, without invalidating the remainder of such
provision or the remaining provisions of this Agreement.

               7.5 Application of Payment. Debtor irrevocably waives the right
to direct the application of any and all payments at any time or times hereafter
received by Secured Party from Debtor, and Debtor does hereby irrevocably agree
that Secured Party shall have the continuing exclusive right to apply and
reapply any and all payments received at any time or times hereafter against the
Liabilities hereunder in such manner as Secured Party may deem advisable,
notwithstanding any entry by Secured Party upon any of its books and records.

               7.6 Invalidated Payment. Debtor agrees that to the extent that
Debtor makes a payment or payments to Secured Party, which payment or payments,
or any part thereof, are subsequently invalidated, declared to be fraudulent or
preferential, set aside and/or required to be repaid to Debtor, its estate,
trustee, receiver or any other party under any bankruptcy law, state or federal
law, common law or equitable cause, then to the extent of such payment or
repayment, the Liability or part thereof which has been paid, reduced or
satisfied by the amount so repaid shall be reinstated and included within the
Liabilities as of the date such initial payment, reduction or satisfaction
occurred.

               7.7 Submission to Jurisdiction. DEBTOR CONSENTS TO THE
JURISDICTION OF ANY STATE OR FEDERAL COURT LOCATED WITHIN THE STATE OF ILLINOIS,
AND DEBTOR HEREBY WAIVES PERSONAL SERVICE OF ANY AND ALL PROCESS UPON DEBTOR AND
CONSENTS THAT ALL SUCH SERVICE OF PROCESS BE MADE BY REGISTERED MAIL DIRECTED TO
DEBTOR AT ITS ADDRESS STATED AT THE BEGINNING OF THIS AGREEMENT. SERVICE SO MADE
SHALL BE DEEMED TO BE COMPLETED FIVE (5) DAYS AFTER THE SAME SHALL HAVE BEEN SO
POSTED.

               7.8 Notice. Except as otherwise provided for herein, any
statement, notice or other communication required or permitted hereunder shall
be in writing and may be personally served, sent facsimile transmission or
courier service or United States certified mail and shall be deemed to have been
given when delivered in person or by courier service, upon receipt of a
facsimile transmission, or seven (7) business days after deposit in the United
States or Canadian



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mail with postage prepaid and properly addressed. For the purposes hereof, the
addresses of the parties hereto shall be as follows:

               If to the Debtor, at:

                      AccuMed International, Inc.
                      900 North Franklin Street, Suite 401
                      Chicago, Illinois 60610
                      Attention: Leonard R. Prange
                                  Chief Financial Officer
                      Telecopier:  (312) 642-8684

                      with a copy to:

                      AccuMed International, Inc.
                      1500 7th Avenue
                      Suite 100
                      Sacramento, California 95818
                      Attention:  Joyce L. Wallach, General Counsel
                      Telecopier:  (916) 443-6850

               If to the Secured Party, at:

                      Robert L. Priddy
                      3435 Kingsboro Road #1601
                      Atlanta, Georgia 30326
                      Telecopier:  (404) 842-9431

or, as to each party, at such other address as may be designated by such party
in a written notice to the other party to this Agreement in accordance with this
Section 7.8.



                   [The following page is the signature page]



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               IN WITNESS WHEREOF, this Agreement has been duly executed as of
the day and year first above written.



                                            ACCUMED INTERNATIONAL, INC.



                                            By: __________________________
                                                Name:
                                                Title:



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                                   SCHEDULE A
                                       TO
                               SECURITY AGREEMENT
                           DATED AS OF AUGUST 18, 1997


                         Liens, Claims and Encumbrances
                             Against the Collateral


               None, except:

               (i) Liens for taxes not yet due or liens for taxes being
        contested in good faith and by appropriate proceedings if adequate
        reserves with respect thereto are maintained on the books of the Debtor
        in accordance with generally accepted accounting principles;

               (ii) Liens on property or assets of the Debtor that were incurred
        in the ordinary course of business, such as carriers', warehousemen's,
        landlords' and mechanics' liens and other similar liens arising in the
        ordinary course of business and that (x) do not in the aggregate
        materially detract from the value of the property or assets subject
        thereto or materially impair the use thereof in the operation of the
        business of the Debtor or (y) that are being contested in good faith by
        appropriate proceedings, which proceedings have the effect of preventing
        the forfeiture or sale of the property or assets subject to such lien;

               (iii) Liens (other than any lien imposed by the Employee
        Retirement Income Security Act of 1974, as the same may be supplemented
        or amended from time to time, or in connection with any environmental
        violation), pledges or deposits incurred or made in connection with
        workmen's compensation, unemployment insurance and other social security
        benefits, or securing the performance of bids, tenders, leases,
        contracts (other than for the repayment of borrowed money), statutory
        obligations, progress payments, surety and appeal bonds and other
        obligations of like nature, in each case incurred in the ordinary course
        of business; and

               (iv) Financing statement 003581568 filed with the Illinois
        Secretary of State on August 21, 1996, naming the Debtor as debtor and
        Nortech Telecommunications Inc., as secured party relating to certain
        telephone equipment leased by the Debtor. All of the obligations of the
        Debtor relating to such financing statement have been paid in full.



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                                   SCHEDULE B
                                       TO
                               SECURITY AGREEMENT
                           DATED AS OF AUGUST 18, 1997


                        Locations of Collateral and Books
                       and Records Concerning Collateral;
                           Debtor's Places of Business


               1.     Locations of Collateral:

                      None, except:

                      900 North Franklin Street, Suites 401
                      Chicago, Illinois  60610

               2. Location of Books and Records Concerning the Collateral and
Debtor's Principal Place of Business and Chief Executive Office:

                      900 North Franklin Street, Suite 401
                      Chicago, Illinois  60610

               3.     Debtor's Other Places of Business:

                      920 North Franklin Street, Suites 403 and 405
                      Chicago, Illinois  60610

                      29299 Clemens Road, Suite 1-K
                      Westlake, Ohio 44145

                      29307 Clemens Road
                      Westlake, Ohio 44145

                      1180 Elsworth Road
                      Ann Arbor, Michigan 48108

                      210 Business Park Drive
                      Sun Prairie, Wisconsin 53990



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