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                                                                   Exhibit 10.11

                             TARGUN PROPERTIES, INC.
                            LEASE & SERVICE AGREEMENT


This agreement is made on this 1st day of October between TARGUN PROPERTIES,
INC., an Arizona Corporation (hereinafter referred to as "Lessor"), and NATIONAL
SCIENTIFIC CORPORATION, an Arizona Corporation, (hereinafter referred to as
"Lessee"). Lessor has entered into a lease for the space described below:

        Suite E-160, Offices# 21, 23, 27, 28, 29 & 30
        4455 E Camelback Rd.
        Phoenix, Arizona  85018

Lessee desires to lease from Lessor a certain portion of Suite E-160 for the
purpose of conducting Lessee's business together with the rights in common to
the "Common Areas" of the Suite.

In consideration of the covenants and promises each to the other made herein,
the parties hereto agree as follows:

1.    PREMISES.  In consideration of the rents and covenants to be paid and
performed by Lessee, Lessor does hereby lease to Lessee, and Lessee does
hereby hire from Lessor, upon the terms and conditions hereinafter set forth,
Office Numbers 21, 23, 27, 28, 29 & 30 within the Suite E-160 (The Park
Executive Suites) located at 4455 Camelback Rd. (hereinafter the
"Premises").  All of the property at 4455 E. Camelback Rd., Phoenix, Arizona
85018, including, but not limited to, the buildings, equipment rooms,
grounds, walls, parking areas and driveways is hereinafter referred to as The
Suites.

      A. An exclusive right to occupy offices numbered 21, 23, 27, 28, 29 & 30.
Said office will be occupied by no more than four (4) persons. If any additional
persons occupy the office, Lessee shall pay to Lessor an additional (Fifty
dollars) $50.00 per month for each additional person who occupies the office.

      B. A non-exclusive right in common with other Lessees, their associates,
arid other parties contracting with Lessor to the use of services offered by
Lessor and to the use of the common areas of the Premises, including but not
limited to the reception area, amenities, copy machine room, conference room,
and corridors, as provided by Lessor on this floor in the Suite.

2.    TERM.

      A. The term shall commence on October 1, 2000, and terminate on September
30, 2001, subject to the provisions hereinafter provided.

      B. If the Premises are not ready for occupancy on the commencement date of
the Lease, this Lease shall remain in full force and effect. Lessee should
physically inspect the Premises to verify that the Premises will be ready on any
promised date. Lessor shall not be liable to Lessee for any loss or damages
resulting from the Premises not being ready for occupancy on the commencement
date of this Lease, and the term (Or any rent increase date

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herein) shall not be extended, but in such event all rent shall be abated during
the period between the commencement of the said Term arid the time when the
Premises are available to Lessee, the term of the Lease shall commence, and rent
shall commence without any deduction or offset, on the date Lessee moves into
the leased space or has a telephone installed, whichever occurs first.

      C. Either party may terminate this Lease at the expiration of the term set
forth herein. Lessee must give thirty (30) days written notice to Lessor of
Lessee's intent to terminate the Lease at the expiration of the term. If Lessee
vacates said premises before the expiration date, Lessee will be held
responsible to Lessor for all rent owed until specified termination date. If
Lessee does not renew Lease or sign a new tease prior to the expiration of
Lease, Lessor reserves the right to immediately terminate rental and serve an
immediate eviction notice. Also, if Lessee fails to give thirty (30) day Written
notice of his intent to vacate the premises at the end of the term, Lessee will
automatically be considered a month-to-month tenant and will be responsible for
the current market rental rate of the premises decided at Lessor's discretion,
until such time that Lessee does give thirty (30) days written notice of
Lessee's intent to vacate premises.

3.    RENT.  Lessee agrees to pay to Lessor (as rental for the Premises
described in Paragraph I hereof) the following monthly sum of:

<TABLE>
<S>                                               <C>
          $     4,190.00     Base Rent             $     100.56             State Rental Tax
           -----------------                        -----------------------

          $                  Telephone Rent        $                        Other
           -----------------                        -----------------------
          $                  Telephone Answering   $                        Other
           -----------------                        -----------------------
          $                  Furniture Rental      $     130.00             Covered  Parking
           -----------------                        -----------------------

                                  $     4,420.56     TOTAL MONTHLY RENTAL
                                   -----------------
</TABLE>


All rents shall be due and payable on the first of each month. Rents become
delinquent after the 5th of each month at which time Lessee is considered in
default of Lease and is responsible for any and all penalties set forth herein
as described in paragraph 12 of Lease.

4.    SECURITY DEPOSIT.  Upon execution of this Lease by Lessee, Lessee will
submit a security deposit in the amount of $250.00, $100.00 of which is
non-refundable per office.

      A. Lessee's security deposit represents a bond on the part of the Lessee
for the faithful performance of the provisions of this Lease. The security
deposit will not be interest bearing to Lessee and may be commingled by Lessor
with other funds of Lessor. The security deposit will not and shall not be
applied as rent by Lessor or Lessee, and shall be retained by Lessor during
Lessee's tenancy. If Lessee remains in the Premises after the expiration date of
the Lease, the security deposit will be retained by Lessor until Lessee's
security deposit as is reasonably necessary to remedy and defaults of Lessee in
the payment of rent, to repair damages to the Premises caused by the Lessee, and
the parties expressly agree that the security deposit is made for all the
aforesaid specific purposes. If the space rented has been previously occupied,
Lessee acknowledges inspection of the carpeting, flooring, walls, wall
coverings, ceiling, and door of the leased premises and acknowledges that there
are no holes, stains or other damage

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thereto if not specified in detail at the bottom of the last page of this Lease.
If Lessee's space is not completed or available for inspection, Lessee has ten
(10) days after the commencement date of this Lease to send a letter via
Certified Mail to lessor identifying any holes, stains, or other damages. If
Lessee has paid all of the rent due under this Lease, Lessor shall return to
Lessee the entire security deposit (less $100.00 for cleaning and painting and
any offsets for damages) for each suite occupied by Lessee after sixty (60) days
after Lessee moves out of the Premises. If any law exists or is enacted which
contradicts any provision of these security deposit provisions, Lessor is not
liable to Lessee for any damages unless Lessee sends Lessor by Certified Mail a
copy of the applicable case of code and Lessor fails to cure same within seven
(7) days.

5.    MASTER LEASE. Lessee recognizes that there is a Master Lease of which
Lessee's office (s) is a portion, and Lessee shall have no greater rights to the
use and occupancy of the Premises than Lessor has with the Building under
Lessor's Master Lease. Lessee is bound to Lessor in the same manner as Lessor is
bound to the Building with respect to all standard lease provisions, such as
eminent domain, destruction of building, etc., as well as the rules and
regulations of the Building. Lessee agrees to release and forever hold the
Lessor harmless from any claim of damages, Liabilities or losses alleged or
proven to be due, in whole or in part, to any dispute which might arise between
Lessor and Landlord under the Master Lease. In the event of termination of the
Master Lease, Lessee shall, at the option of Lessor's Landlord, attorn to
Lessor's Landlord and recognize Lessor's Landlord as Lessor under this Sublease.
This Paragraph does not obligate Lessee in any way to the Building or to anyone
else, for anyone else's rent, or any payment whatever, except expressly set
forth in this Agreement. Although Lessor's rent may be increased under the
Master Lease if taxes, utilities or maintenance costs increase, Lessee's rent
will not be increased during the term of this Lease (except otherwise provided
in Paragraph 3 hereof).

      All reference to Lessee in the Agreement is to mean Sub-Lessee; reference
to Lessor is to mean Sub-Lessor; and reference to Lease is to mean Sub-Lease.

6.    IMPROVEMENTS.

      A. Lessee may not make any improvements within the office leased herein
without the written permission of Lessor.

      Lessee shall pay for any such improvements. Lessee may remove any
improvements paid for by Lessee provided that Lessee repairs any holes, gaps or
other damage to walls, ceiling, flooring or their coverings. Lessee will remove
any improvements (other than additional, normal height electrical outlets)
installed by Lessee and restore the Premises to the condition prior to Lessee's
occupancy if the next tenant in that space objects to Lessee's improvements.
Lessee may not remove any improvement for which Lessor contributed payment
without Lessor's prior written consent. During the restoration period, Lessee
shall pay rent to Lessor as provided herein as if said space were otherwise
occupied by Lessee.

      B. If Lessee requires any additional air conditioning or electrical
outlets of separate circuits for a computer or other office equipment, Lessee
will be responsible for the entire cost thereof. Lessee will order all
additional air conditioning or electrical work through, or with the approval of,
the Building Manager.


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7.    REPAIRS. The Building which leases the Premises to Lessor is responsible
for construction of the Premises and repairs to elevator, air conditioning,
electrical, plumbing and structural supports under the Master Lease. Lessor is
not liable to Lessee by reason of any defect, inadequacy, or insufficiency in
same. Lessee may not deduct or offset any amount from rent due herein because of
any problem regarding construction, repairs or lack thereof. Lessor will
coordinate any repair or complaint of Lessee; however, any claim by Lessee with
respect thereto shall be made solely against the Building and Lessor hereby
assigns to Lessee, solely for the purpose of making and prosecuting any claim,
repairs for dangerous conditions existing in the common areas within the Suite.
Lessee is responsible for, and shall indemnify and hold Lessor harmless from and
against, any damage to persons or property caused by Lessee, or Lessee's
employees, agents, clients, guests or invitees. Lessee is not responsible for
repairing wall holes from normal sized nails used to hang pictures.

8.    UTILITIES, SERVICES, MAINTENANCE, AND CONSTRUCTION. Under Lessor's Master
Lease, the Building provides utilities, services (janitorial, heat and air
conditioning), and maintenance. Janitorial services include carpet vacuuming,
but not shampooing. Heat and air conditioning is provided during generally
recognized business days and hours; however, Lessee will have access to the
Premises 24 hours a day, 7 days a week, subject to the Building's rules
requiring proper identification after normal business hours. Lessor is not
liable to Lessee by reason of any failure to provide, or the inadequacy of
utilities, janitorial, heat or air conditioning services or maintenance. Lessor
is not responsible for any negligence of the Building's agents, servants, or
employees. Lessee may not deduct or offset any amount from rent due herein
because of any problem regarding utilities, heat, air conditioning, janitorial
services, maintenance services or defective construction of Premises. Upon
request by Lessee, Lessor will write the Building regarding any complaint about
maintenance or construction; however, any claim by Lessee with respect thereto
shall be made by Lessee directly to the Building, under the Master Lease. Lessor
is not responsible for maintaining, repairing, or cleaning the floor coverings,
wall covering or venetian blinds within Lessee's Premises, other than normal
janitorial service provided by the Building.

      A. EXTRAORDINARY CONSUMPTION OF SERVICES. Lessee shall not, without the
written consent of Lessor, use any apparatus or device in the Premises, other
than a reasonable number of small business machines, that will in any way
increase the amount of electricity or water usually furnished or supplied for
use of the Premises as general office space, or that will materially affect the
temperature otherwise maintained by the air conditioning or heating system. In
Lessor's sole discretion, Lessee agrees to pay promptly upon demand by Lessor
all additional water or electric current consumed, plus any additional expenses
incurred in keeping track of said consumption, including the cost of installing
separate meters in and to the Leased Premises if Lessor deems it necessary.

9.    TELEPHONE AND RECEPTION. Lessor agrees to provide telephone answering for
one Line and reception service as reasonably required by Lessee from 8:00 a.m.
to 5:00 p.m., Monday through Friday, nationally recognized holidays excepted.
Additional lines will be answered at a cost of $25.00 per month per line. Lessee
shall be responsible for its own telephone expense, and the installation and
monthly service charges, if any, from the telephone company by reason of
Lessee's Lines being connected to the reception desk and telephone room


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consoles, whether billed to Lessor or Lessee. Any telephone expense billed to
Lessor (including any telephone company double charge) shall be paid or
reimbursed by Lessee to Lessor.

       If the telephone company does not install Lessee's phone on or before the
commencement date of this Lease, the commencement date shall not be extended,
nor shall rent be abated. Lessor will assist Lessee in ordering lines and
equipment through Lessor's interconnect telephone company; however, it is
Lessee's responsibility to make certain lines are installed in Lessee's office
and to Lessor' central call director in a timely fashion.

      Lessee recognizes that telephone answering and reception services are
never perfect and that even the best receptionists and telephone operators make
mistakes. Lessor strives to provide excellent telephone answering and reception
services; however, reception services are functions that are under the control
of Lessee in that Lessee may perform either or both of these functions directly
through Lessee's employees. Lessee hereby agrees to assume the risk of negligent
(passive and/or active) performance of telephone answering id/or reception
service. Lessee agrees that Lessor shall not be liable for any loss of business
or damage of any sort occurring through or in connection with, or incidental to
the furnishing of, or the failure to furnish, telephone answering or reception
service. Further, Lessee agrees to indemnify, release and hold Lessor harmless
from any loss, damage, claim or liability arising out of or in connection with
any telephone answering and/or reception service provided or not provided by
Lessor's employees to Lessee or to any caller, visitor or associate of Lessee.
Lessor shall not be liable for any loss of business or damages of any sort for
authorizing or permitting the telephone company to disconnect Lessee's telephone
service if Lessee has not paid its telephone bill.

       Lessor acknowledges that Lessee's separate number connected to the
central call director belongs to Lessee. If, upon termination of this Lease, the
telephone company requires Lessor's signature to assign said telephone number to
Lessee, Lessee may sign Lessor's name to the telephone company form.

       Lessee provides open message/mail slots for all tenants. Lessee
acknowledges that Lessor is not responsible for loss or theft of messages or
mail.

       Upon termination of this Lease, Lessor will write on all mail
"Moved-Please Forward to Sender" and return such mail to the post office. Lessor
will not store mail nor place a forwarding address on it unless Lessee pays the
then-prevailing charge for said service.

10.   PARKING. Lessee may have monthly parking in the Building's parking
      facilities, if any, according to the Building's rules, regulations and
rates.

11.   ANIMALS AND VEHICLES. Lessee will not bring, nor permit any of its
      visitors to bring, any animal (except seeing-eye dog), bicycle or other
vehicle (except for a wheelchair) into the Suite.

12.   DEFAULT; REMEDIES.

      A. By Lessee. Lessee will be in default under the Lease if any of the
following occurs:


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            1. If Lessee fails to pay the rent or make any other payment
required by the Lease within three (3) working days after Lessor sends Lessee a
written notice or demand for payment

            2. If on three or more occasions in any twelve month period Lessor
does not receive either Lessee's regular monthly payment of rent and other
regularly recurring charges on or before the first business day of the month or
any other payment on or before the date it is due.

            3. If Lessee assigns the Lease or mortgages its interest in the
Lease or sublets any part of the Premises.

            4. If Lessee abandons the Premises, or ceases to operate its
business on the Premises, or becomes bankrupt or insolvent, or makes any general
assignment of all or a substantial part of its property for the benefit of
creditors, or if a receiver is appointed to operate Lessee's business or to take
possession of all or a substantial part of Lessee's property.

            5. If Lessee fails to maintain the insurance as required by the
Lease.

            6. If Lessee breaches any other provision of the Lease and fails to
cure the breach within fifteen (15) days after Lessor sends written notice of
the breach, or, if the breach cannot be cured within fifteen days, then if
Lessee does not proceed with reasonable diligence to cure the breach within such
additional time as may be reasonably necessary under the circumstances.

            7. If Lessee is disruptive and/or uses obscenities or vulgar
language so as to disturb any of the other tenants or Lessor's employees.

      B. Lessor's Remedies. If Lessee is in default, then Lessor may take any of
the following actions:

            1. Fees.

                  a.    If rent and monthly service charges have not been
                        received by the 5th of the month, a late charge of
                        $30.00 will be charged.

                  b.    If rent or monthly service charges have not been
                        received by the 6th of the month, an additional late
                        charge of $10.00 per day, or ten percent (10%) of the
                        total monthly rental, whichever is greater, shall be
                        charged until the rent and service charges, including
                        the late charge, are paid in full.

                  c.    If one or more checks are dishonored by Lessee's bank in
                        a twelve (12) month period, Lessor may require, during
                        the balance of the Lessee's tenancy, payment by
                        cashier's check or money order. Lessee's failure to
                        comply therewith will constitute a material breach and
                        permit Lessor to terminate this Lease.


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                  d.    If a check is dishonored by Lessee's bank, a $50
                        returned check fee will be charged.

                  e.    In the event that Lessee becomes delinquent in the
                        payment or rent, or is unable to meet the monthly rental
                        obligation on a timely basis requiring eviction, require
                        cleaning and/or repairs at the expense of Lessor, Lessee
                        agrees to pay all collection agency fees that are
                        required for collection of Lessee's debt.

            2. Re-entry and repossession. Lessor may re-enter and take
possession of all or any part of the Premises and remove Lessee and any person
claiming under Lessee from the Premises, and without committing a trespass or
becoming liable for any loss or damage that may be occasioned thereby. Lessor
may also change the locks to the Premises without notice at Lessee's expense.
Re-entry and repossession of the Premises will not by themselves terminate the
Lease.

            3. Removal, storage and sale of property. Lessor may remove any
property, including fixtures, from the Premises and store the same at Lessee's
expense in a warehouse or any other location, or Lessor may lease the property
on the Premises pending sale or other disposition. if Lessor leaves the property
on the Premises or stores it at another location owned or controlled by Lessor,
then Lessor may charge Lessee a reasonable fee for storing and handling the
property comparable to what Lessor would have had to pay to a third party for
such services. Lessor will not be liable under any circumstances to Lessee or to
anyone else for any damage to the property. Lessor shall proceed to sell
Lessee's property in accordance with Arizona law.

            4. Reletting the Premises. Lessor may relet the Premises at whatever
rent and on whatever terms and conditions it deems advisable. The term of any
new Lease may be shorter or longer than the remaining term of this Lease. In
reletting the Premises, Lessor may make any alterations or repairs to the
Premises it feels are necessary or desirable; may subdivide the Premises into
more than one unit and lease each portion separately; may sell Lessee's
improvements, fixtures and other property located on the Premises to the new
tenant, or include such improvements, fixtures and property as part of the
Premises without additional cost; may advertise the Premises for sale or lease;
may hire brokers or other agents; and, may do anything else it deems necessary
or helpful in reletting the Premises. Lessee will be liable to Lessor for all
costs and expenses of the reletting including but not limited to rental
concessions to the new tenant, broker's commissions and tenant improvements, and
will remain liable for the rent and all other charges arising under the Lease,
less any income received from the new tenant, unless the Lease is terminated as
set forth below.

            5. Termination of Lease. Lessor may terminate the Lease at any time
after Lessee defaults by sending a written notice to Lessee expressly stating
that the Lease is being terminated. Termination will be effective on the date of
the notice or on any other date set forth in the notice. Until Lessor sends
Lessee such a notice, the Lease will remain in full force and effect, and Lessee
will remain liable for paying the rent and other charges that come due under the
Lease and for performing all other terms and conditions of the Lease. No other
action taken by Lessor, including repossession of the Premises, removing or
selling Lessee's separate

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property, reletting the Premises, or filing suit for possession or for damages,
will terminate the Lease or release Lessee from its continuing liability for
complying with its terms and conditions.

            6. Damages. Lessor may recover from Lessee all costs and expenses
Lessor incurs as a direct or indirect consequence of Lessee's breach, including
the cost of storing and selling Lessee's property, reletting the Premises, and
bringing suit against Lessee for possession or damages. If Lessor made or paid
for any improvements to the Premises, or granted Lessee any improvement
allowance or credit against rent for Lessee's improvements, then Lessor shall
also be entitled to recover the unamortized portion of the cost of such
improvements or the amount of such allowance or credit, determined by
multiplying the total amount of such cost or allowance or credit by a fraction,
the denominator of which is the total number of months of the initial lease term
and the numerator of which is the number of months of the term remaining at the
time of Lessee's default. Also, if the Lease provides for any month during which
no rent or a reduced rent is payable, or for any other rent concession to
Lessee, then, upon default, Lessee shall become liable for the full amount of
the monthly base rent, plus applicable taxes, for such months, and Lessor shall
be entitles to recover as additional rent the amount that would have payable by
Lessee for such months if the monthly base rent provided for had been payable
throughout the entire term of the Lease. Unless Lessor terminates the Lease,
Lessee will also remain liable for any difference between the rent and other
charges called for by the Lease and the rent and other charges collected by
Lessor from any new tenant. For any month in which or collects less from a
successor tenant than is payable under this Lease, Lessor may demand that Lessee
immediately make up the difference, and Lessor may bring suit against Lessee if
Lessee fails to do so. If Lessor does terminate the Lease, then Lessee will no
longer be liable on a continuing monthly basis for the rent and other charges
that would have become due under the Lease thereafter, hut Lessee will remain
liable for all sums accrued under the Lease to the date of termination, as well
as for all costs and expenses incurred by Lessor, and any other damages
sustained by Lessor, as a consequence of Lessee's breach. Also, Lessor may
recover from Lessee the difference between the present value at the date of
termination of the rent payable under law or in equity for breach of contract,
damages or other appropriate relief. The rights and remedies described herein
are cumulative, not exclusive, and Lessor's exercise of any one right or remedy
will not preclude the simultaneous or subsequent exercise of any other right or
remedy.

13.   INDEMNIFICATION OF LESSOR; INSURANCE. Lessor shall not be liable or
answerable to Lessee or any other person, firm or corporation for any injury or
damage resulting from the condition, or any defect in, the Premises. Lessee
agrees to indemnify Lessor against, and hold Lessor and the Premises and
Building free and harmless from any and all penalties, costs, expenses
(including attorney's fees), claims, demands and causes of action arising out of
or in connection with (a) any accident or other occurrence in or on the
facilities (including, without limiting the generality of the term "facilities~,
stairways, passageways or hallways), the use of which Lessee may have in
conjunction with other tenants of the Building, which such injury or damage
shall be caused in part or in whole by the act, neglect, fault or omission of
any duty with respect to the same by Lessee, its agents, servants, employees,
invitees, permittees, customers, clients or guest, (b) the condition of, or and
condition of, or any defect in, Lessee's fixtures or equipment or any part
thereof, (c) the use or occupancy of the Premises by Lessee or any tenant of
Lessee, or (d) any breach of this Lease by Lessee. Lessor is not liable for any
lost or stolen items in the possession of Lessee's office.


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      Lessee agrees to and shall at its own cost and expense procure and
maintain during the entire Lease Term and any extensions thereof comprehensive
public liability insurance covering the Premises and their surrounding areas and
naming Lessor as an additional Insured. The liability coverage under such
insurance shall not be less than Five hundred Thousand Dollars ($500,000) for
injury or death of one person in any one accident or occurrence; One Million
Dollars ($1,000,000) for injury or death of more than one person in any one
accident or occurrence; and One Hundred Thousand Dollars ($100,000) for property
damage. The amounts of insurance coverage stated herein may be reduced by mutual
agreement of the parties. Any such reduction must be stated in writing and
executed F ~he parties. Lessee shall provide Lessor with certificates of such
insurance evidencing Lessee's compliance. All policies of insurance also provide
that such insurance will not be canceled, except after ten (10) days written
notice to Lessor. The original of all policies shall remain in the possession of
the Lessee, provided, however, that the Lessor shall be issued copies by a
responsible company or companies authorized to do business in the State of
Arizona. In no event shall the limits of said policies be considered as limiting
the liability of Lessee to Lessor under the first section of this Paragraph 13.

14.   USE OF PREMISES. Lessee shall not do or permit anything to be done which
will invalidate or increase the cost of any fire, extended coverage or any other
insurance policy covering the Building and/or property located therein.

      Lessee shall not do or permit anything to be done in or about the Premises
which will in any way obstruct or interfere with the rights of other tenants or
occupants of the floor, or injure or annoy them, or use or allow the Premises to
be sued for any improper, immoral, unlawful or objectionable purpose, nor shall
Lessee cause, maintain or permit any nuisance in, on or about the Premises. This
prohibition includes, but is not limited to, loud music, other loud noises,
burning incense or other offensive or objectionable odors.

      Lessee may use and occupy the leased Premises for general office use and
for no other business or purpose without written consent of Lessor. Lessee
shall, at its own expense, perform and fully satisfy all laws, statutes, and
regulations which may relate to or affect the occupancy of the leased Premises
or any governmental authorities having jurisdiction over the subject Premises.

15.   KEYS. Lessor will supply one (1) key to the door of each office. Lessee
will pay the Building's prevailing charge for elevator keys, security cards or
keys to enter the building after normal business hours, or additional office
keys. Lessor is not responsible for changing any lock. If the master key kept by
Lessor's receptionist is stolen, lost or misplaced, Lessor is not responsible
for changing Lessee's locks. Lessee understands that Lessor is not liable for
thefts and Lessee may install a dead bolt lock on or change the tumbler to
Lessee's office door (s) upon written approval of Lessor; in which event Lessee
must give a copy of the key to Lessor to be used in emergencies and for
maintenance purposes. Lessee agrees to return all keys to Lessor immediately
upon vacating its office. Failure to return all keys immediately will result in
a charge of Lessee for changing the locks, which will be an amount not less that
Twenty-live Dollars ($25). Lessee agrees to pay this charge within ten (10) days
of request by Lessor.


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16.   ENTRY BY LESSOR. Lessor shall have the right to enter the Premises at any
time to inspect the same or to cure any default including a breach of the
Building's rules and regulations), to supply any service to be provided by
Lessor hereunder, to submit the Premises to prospective purchaser, tenants or
mortgagees, to post notices of non-responsibility, and to alter, improve or
repair the Premises and any portion of the building, without abatement of rent,
necessary structures where reasonably required by the character work to be
performed, always providing that the business of Lessee shall not be interfered
with unreasonably. Lessee hereby waives any claim for damages for any injury,
inconvenience or interference with Lessee's business, any loss of occupancy or
quiet enjoyment of the Premises, and any other loss occasioned by Lessor's entry
for any of the aforesaid purposed.

       For each of the aforesaid purposes, Lessor shall at all times have and
retain a key with which to unlock all of the doors upon the Premises, excluding
Lessee's vaults, and Lessor shall have the right to use any and all means to
open said doors in an emergency in order to obtain entry to the Premises, and
any entry to the Premises obtained by Lessor shall not under any circumstances
constitute forcible or unlawful entry into or a detainer of the Premises or an
eviction of Lessee from the Premises or any portion therefor. Lessor shall not
be liable for the consequences of admitting by passkey, or refusing to admit to
the Premises, Lessee or any agent or employee of Lessee.

17.   LESSOR'S RIGHT TO CURE DEFAULTS. All convents and agreements to be
performed by Lessee under any of the terms of the Lease shall be at its sole
cost and expense and, except as otherwise specifically provided herein, without
any abatement of rent If Lessee shall fail to pay any sum of money other than
rent, required to be paid by it hereunder or shall fail to perform any other act
on its part to be performed hereunder, Lessor may but shall not be obligated so
to do, and without waiving any rights of Lessor or releasing Lessee from any
obligations of Lessee hereunder, make such payment or perform such other act All
sums so paid or expenses incurred by Lessor and all necessary incidental costs
together with interest thereon at the rate of eighteen percent (18%) per annum
from the date of such payment by Lessor shall be considered as rent owing
hereunder and shall be payable to Lessor on demand or, at the option of Lessor,
may be added to any rent then due or thereafter becoming due under this Lease.
In addition, Lessor shall have the same right and remedies in the event of the
nonpayment thereof be Lessee as in the case of default by lessee in the payment
of any rent hereunder.

18.   DELAYS, DEFAULT BY LESSOR. Lessor shall not be responsible for any delay
or failure in the observance or performances of any term or condition of this
Lease to be observed or performed by Lessor to the extent that such delay
results from action or order of governmental authorities; civil commotions;
strikes, fires, acts of God or the public enemy; act or default of any Lessee in
the Building, inability to procure labor, material, fuel, electricity, or other
forms of energy; or any other cause beyond the reasonable control of Lessor,
whether or not similar to the matters herein specifically enumerated. Any delay
shall extend by like time any period or performance by `or and shall not be
deemed a breach of, or failure to perform, this Lease or any provisions thereof.

       In the event of any default under this Lease by Lessor, Lessee, before
exercising any rights that it may have at law to cancel this Lease, shall have
given notice of such default to Lessor and shall have offered Lessor a
reasonable opportunity to correct and cure the default.

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<PAGE>   11
Lessee also agrees to give the holders of any mortgages or deeds of trust
(mortgages), by registered mail, a copy of any notice of default served upon
Lessor, provided that prior to such notice Lessee has been notified in writing
(by way of Notice of Assignment of Rents and Leases, or otherwise) of the
addresses of such mortgagees. Lessee further agrees that if Lessor shall have
failed to cure such default within the aforesaid time limit, then the mortgagees
shall have an additional thirty (30) days within which to cure such default or
if such default cannot be cured within that time, then such additional time as
may be necessary if within such thirty (30) days any mortgagees has commenced
and is diligently pursuing the remedies necessary to cure such default
(including but not limited to commencement of foreclosure proceedings if
necessary to effect such cure), in which event this Lease shall not be
terminated while such remedies are being so diligently pursued.

19.   NOTICE TO LESSOR OR LESSEE. All notices required or desired to be given
under this Lease must be in writing and shall he personally given or delivered
by certified or registered mail addressed to the Lessee at the address of the
Premises and to the Lessor at the address of the Suite in which the Premises are
located. Personal delivery to the floor receptionist does not constitute notice
to either Lessor or Lessee. Either party may, by written notice to the other,
specify a different address for notice purposes.

20.   TENANT HOLDOVER. In the event that Lessee, without the written consent of
Lessor shall hold over the expiration of the term of this Lease, then Lessee
hereby waives all notice to quit and agrees to pay Lessor, for the period that
the Lessee is in possession after the expiration of this Lease, a monthly rental
which is twice the total monthly rental payable pursuant to Paragraph 3 of this
Lease, together with all damages sustained by Lessor on account of such holding
over. If Lessee occupies any part of the Premises for any portion of any
calendar month, Lessee will be liable for rent for the full calendar month.
Lessee expressly agrees to hold Lessor harmless for all loss and damages, direct
or consequential, which Lessor may suffer in defense of claims by other parties
against Lessor arising out of the holding over by Lessee, including without
limitation, attorney's fees which may be incurred by Lessor in defense of such
claims. The foregoing provision shall not service as permission for Lessee to
hold over nor serve to extend the term of this Lease. Acceptance of rent by the
Lessor subsequent to the expiration of the term shall not constitute consent to
any holding over.

21.   TRANSFER OF LESSOR'S INTEREST. In the event Lessor transfers its
reversionary interest in the Premises (other than a transfer for security
purposes only), Lessor shall be relieved of all obligations accruing hereunder
after the effective date of such transfer, including, but not limited to, the
return of security deposits or other funds held by Lessor, provided that such
obligations have expressly assumed in writing by the transferee, and Lessee
agreed to attorn to the transferee.

      Lessee agrees at any time and from time to time at the request of Lessor,
to execute, acknowledge and deliver to Lessor within ten (10) days from the date
of said request, a statement in writing certifying that this Lease is unmodified
and in full and effect (or if there have been modifications), and the dates to
which the fixed rent and other charges have been paid in advance, if any, it
being intended that any such statement delivered pursuant to this paragraph may
be relied upon by any prospective purchaser, mortgagee or assignee of any
mortgage of the Premises.


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<PAGE>   12
22.   RETURN OF POSSESSION. Lessee shall vacate the leased Premises in good
order and repair in which such property was at the commencement of this Lease,
ordinary wear and tear excepted. Lessee shall remove all its property no later
than 5:00 p.m. on the day upon which this Lease or any extension thereof ends
whether upon notice or by holdover or otherwise. Lessor shall have the same
rights to enforce this covenant by ejectment and for damages or otherwise as for
the breach of any other conditional therein, and remove from the leased Premises
all property, materials or equipment installed by Lessee, provided that such
property is removed without injury of the leased Premises.

23.   CONFERENCE ROOM. Lessee may use the conference room(s) on a reserved basis
or without reservation if not previously reserved. Lessee will not be allowed to
request any standing or permanent reservation of the conference room(s). Lessee
will pay the then-current rate for conference room usage over five (5) hours per
calendar month per office leased. Any use of the conference room(s) by Lessee's
visitors will be considered to be use by Lessee, whether or not Lessee is
present at the time of such use, and Lessee will be responsible for any charges
incurred for such use.

24.   LESSOR'S EMPLOYEES. Lessee acknowledges that Lessor expends substantial
amounts of money and effort to acquire, train and retain employees for the
services provided to Lessee, including employment agency and training costs.
Lessee agrees that during the term of, or any extension or renewal of, the Lease
and for a period on one (1) year thereafter, Lessee will not hire or attempt to
hire in any capacity whatever, full-time, part-time or on a work for hire basis,
on behalf of itself or any person or entity by whom Lessee (if an individual) is
employed, any employee of Lessor. This prohibition shall apply during the period
of any such employee's employment by Lessor and for ninety (90) days thereafter.
The parties agree that it would be very difficult to ascertain the damages
suffered by Lessor for Lessee's breach of the provision. Therefore, it is agreed
that in the event of a breach of this provision by Lessee, Lessee will pay to
Lessor as liquidated damages, and not as a penalty, a sum of money equal to
three (3) months pay for the subject employee at the rate paid by Lessor during
such employee's last full month employment by Lessor.

25.   ATTORNEY'S FEES. In the event it becomes necessary for either party to
employ an attorney in order to enforce the terms of this Lease, or to protect
the rights of either party hereunder, and such party is successful in an action
in connection therewith, the other party agrees to pay such prevailing party the
reasonable attorney's fees and legal costs incurred.

26.   COVENANT NOT TO COMPETE. Tenant agrees that during the terms of this
Lease, he shall not in or about the Premises, engage in the primary or
incidental business of providing photocopy service, facsimile receipt and
transmissions, secretarial services of any kind, or any similar services which
are provided by Lessor for the benefit of its tenants.


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LESSEE:                                    LESSOR:
      /s/ L.L. Ross                        TARGUN PROPERTIES, INC.
------------------------------------
BY:         L.L. Ross                      BY:   /s/ Michael Targun
   ---------------------------                ---------------------

TITLE:      Chairman/CEO                   TITLE:      President
      ------------------------                   ---------------

S.S.#/TAX ID            86-087077
            ---------------------

HOME
ADDRESS:
        -------------------------

---------------------------------

---------------------------------

PHONE:
        -------------------------
DATE:
        -------------------------


                                       13
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                                 LEASE ADDENDUM



This amendment supplements and amends the provisions of the Lease Agreement
dated August 7, 1998, by and between TARGUN PROPERTIES, INC. (Lessor") and,
NATIONAL SCIENTIFIC CORPORATION ("Lessee"). In the event of any conflict or
inconsistency between the provisions of this Amendment and the provisions of the
Lease, this Amendment shall prevail.



                  LEASE ADDENDUM EXPIRING SEPTEMBER 30, 2001

        (initials)                                            /s/ MG (initials)
--------                                                      ------


      Effective Date:  February 12, 2001

As of February 12, 2001, National Scientific will occupy Office 24 at the rate
of $910 per month until Unit 22 is available (estimated date of availability:
4/1/01) The security deposit from Unit 24 will be applied to Unit 22 upon
occupation. The Monthly rate for Unit 22 will be reduced $100.00/month, for a
monthly total of $1,210.00.*

Terms and conditions: Except to the extent inconsistent with the terms and
conditions set forth above, all the conditions and covenant of that certain
Lease Agreement dated August 21, 1998 as well as all exhibits, schedules,
attachments, addendums of clarification shall be binding upon Lessor and Lessee.
This agreement shall not constitute an agreement by the Lessor and shall not be
binding upon Lessor unless and until the Agreement shall be executed by both
parties.



AGREED TO this 16 day of February, 2001.

LESSEE:                                         LESSOR:

NATIONAL SCIENTIFIC CORPORATION           TARGUN PROPERTIES, INC.

      /s/ Michael Grollman                                  /s/ Michael Targun
------------------------------------------      -------------------------------

Its:        COO                                 Its:  President
    --------------------------------                --------------------------

* The following sentence was written in and initialed by the parties: If Unit 22
is not available by 4/1/00, then this lease amendment is void.