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                                                                   EXHIBIT 10.38

                                PROMISSORY NOTE
                                ---------------

U.S. $320,000.00                                             December 29, 2000

     FOR VALUE RECEIVED, the undersigned, MONOGEN, INC., a Nevada corporation
("Maker"), hereby promises to pay ACCUMED INTERNATIONAL, INC., an Illinois
corporation ("Payee"), at 920 North Franklin Street, Suite 402, Chicago,
Illinois 60610, or at such other place as the holder of this Note may from time
to time designate in writing, the principal sum of Three Hundred Twenty Thousand
U.S. Dollars (U.S. $320,000.00), payable in lawful money of the United States of
America in installments as follows:

     Eighty Thousand U.S. Dollars (U.S. $80,000.00) shall be due and payable on
     or before January 31, 2001;

     Eighty Thousand U.S. Dollars (U.S. $80,000.00) shall be due and payable on
     or before February 28, 2001; and

     The remaining principal balance of the Note shall be due and payable on or
     before March 31, 2001.

     This Note may be prepaid in full or in part at any time without premium or
penalty. All prepayments shall be applied against installments of principal due
hereunder in the inverse order of their maturity.

     Without affecting the liability of any maker, indorser, surety or
guarantor, the holder may, from time to time and without notice, renew or extend
the time for payment, accept partial payment of any or all installments due
hereunder, release or impair any collateral security for payment of this Note,
or agree not to sue any party liable hereunder.

     An Event of Default shall be deemed to have occurred under this Note if
Maker (a) fails to make any payment of principal within five (5) business days
of such payment's due date; (b) makes any assignment for the benefit of
creditors; (c) has a receiver, liquidator or trustee appointed for all or
substantially all of Maker's assets; (d) is adjudicated insolvent; or (e) files
a petition for bankruptcy or reorganization.

     Upon the occurrence of an Event of Default, Payee may, upon five (5)
business days' prior written notice to Maker, declare the entire unpaid balance
of this Note immediately due and payable (the "Default Payment Date"). In the
event that Payee so declares the entire unpaid balance of the Note due and
payable, interest thereon shall accrue from the Default Payment Date until paid
in full at a rate per annum equal to the prime rate as published in The Wall
Street Journal on the issue date nearest the Default Payment Date.

     This Note shall be governed by, and shall be construed and interpreted in
accordance with, the internal laws of the State of Illinois, without reference
or regard to the conflicts of law rules thereof. The parties hereto agree that
exclusive jurisdiction and venue in any action relating to this Note shall be in
the Federal District Court located in



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Chicago, Illinois, or in Illinois state courts of general jurisdiction located
in Chicago, Illinois.

     If any provision in this Note is held invalid or unenforceable by any court
of competent jurisdiction, the other provisions of this Note will remain in full
force and effect. Any provision of this Note held invalid or unenforceable only
in part or degree will remain in full force and effect to the extent not held
invalid or unenforceable.

     All words used in this Note will be construed to be of such gender or
number as the circumstances require. Unless otherwise expressly provided, the
words "hereof" and "hereunder" and similar references refer to this Note in its
entirety and not to any specific section or subsection hereof.

     IN WITNESS WHEREOF, Maker has executed and delivered this Note as of the
date first stated above.



                                  MONOGEN, INC.



                                  By:      /s/ PETER J.N. KILNER
                                     -----------------------------------------
                                     Peter J.N. Kilner, Vice President