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                                                                   EXHIBIT 10.37

                                     SECURED
                                 PROMISSORY NOTE

$225,000.00                                                        March 1, 2001
                                                               Chicago, Illinois

       1. FOR VALUE RECEIVED, AccuMed International, Inc. ("Maker"), whose
principal place of business is located at 920 North Franklin Street, Suite 402,
Chicago, Illinois 60610, hereby promises to pay to the order of Ampersand
Medical Corporation ("Payee"), whose principal place of business is located at
414 North Orleans, Suite 510, Chicago, Illinois 60610, the principal sum of TWO
HUNDRED TWENTY FIVE THOUSAND AND NO/100 DOLLARS ($225,000.00), at the place and
in the manner hereinafter provided, together with interest thereon at the rates
described below.

       2. Interest shall accrue on the balance of principal from time to time
unpaid under this Note prior to the Maturity Date (as hereinafter defined) at an
annual rate equal to Prime plus two and one-half percent (22%). For purposes
hereof, "Prime" shall mean the rate of interest from time to time announced by
LaSalle Bank, National Association ("Bank"), as its Prime Rate, which is not
necessarily the Bank=s lowest or most favorable rate of interest at any given
time. Interest shall be computed on the basis of a year consisting of 360 days
and shall be based on the actual number of days during the period for which
interest is being charged.

       3. Principal and interest under this Note shall be due and payable on the
earlier to occur of the following: (i) termination of the contemplated merger
transaction as outlined in the Merger Agreement (as such term is defined in
paragraph 4 hereof); and (ii) May 31, 2001 or such later date as the parties to
the Merger Agreement may, from time to time, establish as the termination date
of the Merger Agreement by amendment thereto (such payment due date being
hereinafter referred to as the "Maturity Date"); provided, however, the Maturity
Date shall be automatically extended (without requiring a written amendment
hereto) to such later date, if any, as Maker and Payee agree by amendment of the
date specified in Section 4.4(a)(v) of the Merger Agreement (as such term is
hereinafter defined).

       4. This Note is executed and delivered in connection with that certain
Agreement and Plan of Merger, dated as of February 7, 2001 by and between Payee
and Maker (the "Merger Agreement"), pursuant to which the parties thereto have
agreed to enter into the merger described therein. This Note evidences an
Additional Loan (as such term is defined in the Merger Agreement) from Payee to
Maker referred to in paragraph 1.12 of the Merger Agreement.

       5. From and after the Maturity Date, or during any period in which an
Event of Default (as hereinafter defined) exists under this Note, Maker shall
pay interest on the balance of principal then remaining unpaid at an annual rate
(the "Default Rate") equal to Prime plus five percent (5%). The interest
accruing under this paragraph 5 shall be immediately due and payable by Maker to
the holder of this Note on demand and shall be additional indebtedness evidenced
by this Note.


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       6. Maker reserves the privilege, without penalty or premium therefor, to
prepay all or any part of the principal balance of this Note at any time and
from time to time upon two (2) business days prior written notice to Payee of
its intention to do so.

       7. All payments and prepayments on account of the indebtedness evidenced
by this Note shall be first applied to accrued and unpaid interest on the unpaid
principal balance of this Note, and second to all other sums then due Payee
hereunder.

       8. All payments of principal and interest hereunder shall be paid by
check or in coin or currency and shall be made at Payee=s principal place of
business, as hereinabove set forth. Payment made by check shall be deemed paid
on the date Payee receives such check; provided, however, that if such check is
subsequently returned to Payee unpaid due to insufficient funds or otherwise,
the payment shall not be deemed to have been made and shall continue to bear
interest until collected. If payment hereunder becomes due and payable on a
Saturday, Sunday or legal holiday under the laws of the State of Illinois, the
due date thereof shall be extended to the next succeeding business day, and
interest shall be payable thereon at the then applicable interest rate during
such extension.

       9. An Event of Default shall occur hereunder if: (1) any amount payable
hereunder is not paid when due; or (2) Maker shall otherwise fail to perform any
of the promises to be performed by Maker hereunder or under any security
agreement with Payee relating thereto; or (3) Maker or any person who is or
shall become primarily or secondarily liable for any payment hereunder, who is a
natural person, dies; or (4) Maker or any other party liable with respect to any
payment hereunder, or any guarantor or accommodation endorser or third party
pledgor, shall make any assignment for the benefit of creditors, or there shall
be commenced by or against Maker or any such party any bankruptcy, receivership,
insolvency, reorganization, dissolution or liquidation proceedings, or there
shall be the entry of any judgment, levy, attachment, garnishment or other
process, or the filing of any lien, against any of the Collateral (as such term
is defined in the Security Agreement referred to in paragraph 12 hereof); or (5)
in the opinion of Payee, acting in good faith, there is any deterioration or
impairment of any of the Collateral, or any actual decline or depreciation in
the value or market price thereof that causes the Collateral to become
unsatisfactory as to value, and the Payee has provided Maker with written notice
describing the basis of such opinion, and if Maker has failed, within five (5)
business days after receiving such notice to (x) provide documents effectively
refuting such opinion to Payee=s satisfaction, or (y) provide additional
Collateral to eliminate the deficit or pay down the indebtedness in an amount
sufficient to erase such deficit; or (6) there is a determination by Payee that
a material adverse change has occurred in the financial condition of the Maker
from the condition set forth in the most recent financial statement of Maker
furnished to Payee, or from the financial condition of the Maker most recently
disclosed to Payee in any manner; or (7) Maker shall fail to do any commercially
reasonable act necessary to preserve or maintain the value and collectability of
the Collateral; or (8) Maker shall fail, within five (5) business days after
receiving a written request by Payee, to permit inspection by Payee (during
normal business hours) of Maker=s books and records pertaining to the
Collateral; or (9) any guarantor of this Note shall discontinue or contest the
validity of such guaranty; or (10) there shall occur any material adverse event
that causes a change in the financial condition of Maker, or that would have a
material adverse effect on the business of Maker.


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       10. At the election of the holder hereof, whenever Maker shall be in
default as aforesaid (an "Event of Default"), and all applicable cure periods
have expired without a cure having been effected, then without demand or notice
of any kind, the entire unpaid principal amount hereof, and all interest accrued
thereon, shall become immediately due and payable. Failure of the holder to
exercise such election shall not constitute a waiver of the right to exercise
the same in the event of any subsequent Event of Default. No holder hereof
shall, by any act of omission or commission, be deemed to waive any of its
rights, remedies or powers hereunder or otherwise unless such waiver is in
writing and signed by the holder hereof, and then only to the extent
specifically set forth therein. The rights, remedies and powers of the holder
hereof, as provided in this Note, are cumulative and concurrent, and may be
pursued singly, successively or together against Maker and any security given at
any time to secure the repayment hereof, all at the sole discretion of the
holder hereof. If any suit or action is instituted or attorneys are employed to
collect this Note or any part thereof, Maker promises and agrees to pay all
costs of collection, including reasonable attorneys= fees and court costs.

       11. Maker hereby (i) waives presentment and demand for payment, notice of
nonpayment and of dishonor, protest of dishonor, and notice of protest; and (ii)
waives any and all lack of diligence and delays in the enforcement of the
payment hereof.

       12. This Note is secured by that certain Security Agreement, dated as of
the date hereof, pursuant to which Maker has pledged certain of its assets and
property, as described therein, as security for the payment hereof.

       13. This Note evidences a business loan that comes within the purview of
Section 205/4, paragraph (1)(c) of Chapter 815 of the Illinois Compiled
Statutes, as amended. Maker agrees that the obligation evidenced by this Note is
an exempted transaction under the Truth In Lending Act, 15 U.S.C., Section 1601,
et seq.

       14. Time is of the essence hereof.

       15. This Note is governed and controlled as to validity, enforcement,
interpretation, construction, effect and in all other respects by the statutes,
laws and decisions of the State of Illinois, without regard to conflicts of laws
principles. This Note may not be changed or amended orally but only by an
instrument in writing signed by the party against whom enforcement of the change
or amendment is sought.

       16. This Note has been made and delivered at Chicago, Illinois and all
funds disbursed to or for the benefit of Maker will be disbursed in Chicago,
Illinois.

       17. The obligations and liabilities of Maker under this Note shall be
binding upon and enforceable against Maker and its successors and assigns. This
Note shall inure to the benefit of and may be enforced by Payee and its
successors and assigns.

       18. In the event one or more of the provisions contained in this Note
shall for any reason be held to be invalid, illegal or unenforceable in any
respect by a court of competent


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jurisdiction, such invalidity, illegality or unenforceability shall not affect
any other provision of this Note, and this Note shall be construed as if such
invalid, illegal or unenforceable provision had never been contained herein.
Payee shall not collect a rate of interest on the principal balance under this
Note in excess of the maximum contract rate of interest permitted by applicable
law. All interest found in excess of that rate of interest allowed and collected
by Payee shall be applied to the principal balance in such manner as to prevent
the payment and collection of interest in excess of the rate permitted by
applicable law.

       IN WITNESS WHEREOF, Maker has executed this Note as of the date first
hereinabove written.

                                   ACCUMED INTERNATIONAL, INC.

                                   By:   /s/ PAUL F. LAVALLEE
                                      ------------------------------------------
                                         Paul F. Lavallee, Chairman of the Board
                                         and Chief Executive Officer