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                                                                   EXHIBIT 10.42

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                             STOCK PURCHASE WARRANT




                          To Purchase Common Stock of




                          ACCUMED INTERNATIONAL, INC.





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THIS WARRANT AND THE SHARES OF COMMON STOCK INTO WHICH IT IS EXERCISABLE HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE "ACT") NOR UNDER ANY
STATE SECURITIES LAW AND MAY NOT BE PLEDGED, SOLD, ASSIGNED OR OTHERWISE
TRANSFERRED UNTIL A (1) REGISTRATION STATEMENT UNDER THE ACT AND ANY APPLICABLE
STATE SECURITIES LAW HAS BECOME EFFECTIVE WITH RESPECT THERETO, OR (2) RECEIPT
BY THE COMPANY OF AN OPINION OF COUNSEL TO THE COMPANY TO THE EFFECT THAT
REGISTRATION UNDER THE ACT OR APPLICABLE STATE SECURITIES LAW IS NOT REQUIRED
IN CONNECTION WITH THE PROPOSED TRANSFER.


             Void after 5:00 p.m. New York Time, on March 13, 2002.
              Warrant to Purchase 200,000 Shares of Common Stock.


                        WARRANT TO PURCHASE COMMON STOCK

                                       OF

                          ACCUMED INTERNATIONAL, INC.



         This is to Certify That, FOR VALUE RECEIVED, Commonwealth Associates,
or assigns ("Holder"), is entitled to purchase, subject to the provisions of
this Warrant, from AccuMed International, Inc., a Delaware corporation
("Company"), 200,000 fully paid, validly issued and nonassessable shares of
Common Stock, par value $.01 per share, of the Company ("Common Stock") at a
price of $3.125 per share at any time or from time to time during the period
from the Initial Warrant Exercise Date (defined below) to March 13, 2002, but
not later than 5:00 p.m. New York City Time, on March 13, 2002.  The number of
shares of Common Stock to be received upon the exercise of this Warrant and the
price to be paid for each share of Common Stock may be adjusted from time to
time as hereinafter set forth.  The shares of Common Stock deliverable upon
such exercise, and as adjusted from time to time, are hereinafter sometimes
referred to as "Warrant Shares" and the exercise price of a share of Common
Stock in effect at any time and as adjusted from time to time is hereinafter
sometimes referred to as the "Exercise Price".  This Warrant, together with
warrants of like tenor, constituting in the aggregate warrants (the "Warrants")
to purchase up to 200,000 shares of Common Stock, was originally issued
pursuant to an agency agreement between the Company and Commonwealth Associates
("Commonwealth"), in connection with a private placement ("Private Placement")
through Commonwealth of Units, in consideration of $20 received for the
Warrants.





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         (a)     EXERCISE OF WARRANT.

                 (1)      This Warrant may be exercised in whole or in part at
any time or from time to time on or after the date in which the Company has a
sufficient number of authorized shares of Common Stock reserved for issuance
(after taking into account all shares reserved for issuance on the conversion
of convertible securities and the exercise of outstanding options and warrants,
including the shares of Common Stock issuable upon the conversion of the Notes
and exercise of the Warrants issued in the Private Placement) to permit the
issuance of the shares of Common Stock to be issued pursuant to the exercise of
this Warrant ("Initial Warrant Exercise Date") and until March 13, 2002 (the
"Exercise Period"), subject to the provisions of Section (j)(2) hereof;
provided, however, that (i) if either such day is a day on which banking
institutions in the State of New York are authorized by law to close, then on
the next succeeding day which shall not be such a day, and (ii) in the event of
any merger, consolidation or sale of substantially all the assets of the
Company as an entirety, resulting in any distribution to the Company's
stockholders, prior to March 13, 2002, the Holder shall have the right to
exercise this Warrant commencing at such time through March 13, 2002 into the
kind and amount of shares of stock and other securities and property (including
cash) receivable by a holder of the number of shares of Common Stock into which
this Warrant might have been exercisable immediately prior thereto.  This
Warrant may be exercised by presentation and surrender hereof to the Company at
its principal office, or at the office of its stock transfer agent, if any,
with the Purchase Form annexed hereto duly executed and accompanied by payment
of the Exercise Price for the number of Warrant Shares specified in such form.
As soon as practicable after each such exercise of the warrants, but not later
than seven (7) days from the date of such exercise, the Company shall issue and
deliver to the Holder a certificate or certificate for the Warrant Shares
issuable upon such exercise, registered in the name of the Holder or its
designee.  If this Warrant should be exercised in part only, the Company shall,
upon surrender of this Warrant for cancellation, execute and deliver a new
Warrant evidencing the rights of the Holder thereof to purchase the balance of
the Warrant Shares purchasable thereunder.  Upon receipt by the Company of this
Warrant at its office, or by the stock transfer agent of the Company at its
office, in proper form for exercise, the Holder shall be deemed to be the
holder of record of the shares of Common Stock issuable upon such exercise,
notwithstanding that the stock transfer books of the Company shall then be
closed or that certificates representing such shares of Common Stock shall not
then be physically delivered to the Holder.

                 (2)      At any time during the Exercise Period, the Holder
may, at its option, exchange this Warrant, in whole or in part (a "Warrant
Exchange"), into the number of Warrant Shares determined in accordance with this
Section (a)(2), by surrendering this Warrant at the principal office of the
Company or at the office of its stock transfer agent, accompanied by a notice
stating such Holder's intent to effect such exchange, the number of Warrant
Shares to be exchanged and the date on which the Holder requests that such
Warrant Exchange occur (the "Notice of Exchange").  The Warrant Exchange shall
take place on the date specified in the Notice of Exchange or, if later, the
date the Notice of Exchange is received by the Company (the "Exchange Date").
Certificates for the shares issuable upon such Warrant Exchange and, if





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applicable, a new warrant of like tenor evidencing the balance of the shares
remaining subject to this Warrant, shall be issued as of the Exchange Date and
delivered to the Holder within seven (7) days following the Exchange Date.  In
connection with any Warrant Exchange, this Warrant shall represent the right to
subscribe for and acquire the number of Warrant Shares (rounded to the next
highest integer) equal to (i) the number of Warrant Shares specified by the
Holder in its Notice of Exchange (the "Total Number") less (ii) the number of
Warrant Shares equal to the quotient obtained by dividing (A) the product of
the Total Number and the existing Exercise Price by (B) the current market
value of a share of Common Stock.  Current market value shall have the meaning
set forth Section (c) below, except that for purposes hereof, the date of
exercise, as used in such Section (c), shall mean the Exchange Date.

         (b)     RESERVATION OF SHARES.  The Company agrees to use its best
efforts to take all actions as may be necessary (including obtaining
stockholder approval) to amend its Certificate of Incorporation to increase the
Company's authorized shares of Common Stock in order for the Company to have a
sufficient number of authorized shares of Common Stock (after taking into
account all shares reserved for issuance on the conversion of convertible
securities and the exercise of outstanding options and warrants) to permit the
Company to reserve for issuance out of its authorized Common Stock (in addition
to shares of Common Stock reserved for issuance on the conversion and/or
exercise of currently outstanding convertible securities, options and warrants)
all shares issuable upon exercise of this Warrant.  Thereafter, the Company
shall at all times reserve for issuance and/or delivery upon exercise of this
Warrant such number of shares of its Common Stock as shall be required for
issuance and delivery upon exercise of this Warrant.

         (c)     FRACTIONAL SHARES.  No fractional shares or script
representing fractional shares shall be issued upon the exercise of this
Warrant.  With respect to any fraction of a share called for upon any exercise
hereof, the Company shall pay to the Holder an amount in cash equal to such
fraction multiplied by the current market value of a share, determined as
follows:

                 (1)      If the Common Stock is listed on a national
         securities exchange or admitted to unlisted trading privileges on such
         exchange or listed for trading on the Nasdaq National Market, the
         current market value shall be the last reported sale price of the
         Common Stock on such exchange or market on the last business day prior
         to the date of exercise of this Warrant or if no such sale is made on
         such day, the average closing bid and asked prices for such day on
         such exchange or market; or

                 (2)      If the Common Stock is not so listed or admitted to
         unlisted trading privileges, but is traded on the Nasdaq SmallCap
         Market, the current Market Value shall be the average of the closing
         bid and asked prices for such day on such market and if the Common
         Stock is not so traded, the current market value shall be the mean of
         the last reported bid and asked prices reported by the





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         National Quotation Bureau, Inc. on the last business day prior to the
         date of the exercise of this Warrant; or

                 (3)      If the Common Stock is not so listed or admitted to
         unlisted trading privileges and bid and asked prices are not so
         reported, the current market value shall be an amount, not less than
         book value thereof as at the end of the most recent fiscal year of the
         Company ending prior to the date of the exercise of the Warrant,
         determined in such reasonable manner as may be prescribed by the Board
         of Directors of the Company.

         (d)     EXCHANGE, TRANSFER, ASSIGNMENT OR LOSS OF WARRANT.  This
Warrant is exchangeable, without expense, at the option of the Holder, upon
presentation and surrender hereof to the Company or at the office of its stock
transfer agent, if any, for other warrants of different denominations entitling
the holder thereof to purchase in the aggregate the same number of shares of
Common Stock purchasable hereunder.  Upon surrender of this Warrant to the
Company at its principal office or at the office of its stock transfer agent,
if any, with the Assignment Form annexed hereto duly executed and funds
sufficient to pay any transfer tax, the Company shall, without charge, execute
and deliver a new Warrant in the name of the assignee named in such instrument
of assignment and this Warrant shall promptly be cancelled.  This Warrant may
be divided or combined with other warrants which carry the same rights upon
presentation hereof at the principal office of the Company or at the office of
its stock transfer agent, if any, together with a written notice specifying the
names and denominations in which new Warrants are to be issued and signed by
the Holder hereof.  The term "Warrant" as used herein includes any Warrants
into which this Warrant may be divided or exchanged.  Upon receipt by the
Company of evidence satisfactory to it of the loss, theft, destruction or
mutilation of this Warrant, and (in the case of loss, theft or destruction) of
reasonably satisfactory indemnification, and upon surrender and cancellation of
this Warrant, if mutilated, the Company will execute and deliver a new Warrant
of like tenor and date.  Any such new Warrant executed and delivered shall
constitute an additional contractual obligation on the part of the Company,
whether or not this Warrant so lost, stolen, destroyed, or mutilated shall be
at any time enforceable by anyone.

         (e)     RIGHTS OF THE HOLDER.  The Holder shall not, by virtue hereof,
be entitled to any rights of a shareholder in the Company, either at law or
equity, and the rights of the Holder are limited to those expressed in the
Warrant and are not enforceable against the Company except to the extent set
forth herein.

         (f)     ANTI-DILUTION PROVISIONS.  The Exercise Price in effect at any
time and the number and kind of securities purchasable upon the exercise of the
Warrants shall be subject to adjustment from time to time upon the happening of
certain events as follows:

                 (1)      In case the Company shall (i) declare a dividend or
         make a distribution on its outstanding shares of Common Stock in
         shares of Common Stock, (ii) subdivide or reclassify its outstanding
         shares of Common Stock into a





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         greater number of shares, or (iii) combine or reclassify its
         outstanding shares of Common Stock into a smaller number of shares,
         the Exercise Price in effect at the time of the record date for such
         dividend or distribution or of the effective date of such subdivision,
         combination or reclassification shall be adjusted so that it shall
         equal the price determined by multiplying the Exercise Price by a
         fraction, the denominator of which shall be the number of shares of
         Common Stock outstanding after giving effect to such action, and the
         numerator of which shall be the number of shares of Common Stock
         outstanding immediately prior to such action.  Such adjustment shall
         be made successively whenever any event listed above shall occur.

                 (2)      In case the Company shall fix a record date for the
         issuance of rights or warrants to all holders of its Common Stock
         entitling them to subscribe for or purchase shares of Common Stock (or
         securities convertible into Common Stock) at a price (the
         "Subscription Price") (or having a conversion price per share) less
         than the current market price of the Common Stock (as defined in
         Subsection (8) below) on the record date mentioned below, or less than
         the Exercise Price on such record date the Exercise Price shall be
         adjusted so that the same shall equal the lower of (i) the price
         determined by multiplying the Exercise Price in effect immediately
         prior to the date of such issuance by a fraction, the numerator of
         which shall be the sum of the number of shares of Common Stock
         outstanding on the record date mentioned below and the number of
         additional shares of Common Stock which the aggregate offering price
         of the total number of shares of Common Stock so offered (or the
         aggregate conversion price of the convertible securities so offered)
         would purchase at such current market price per share of the Common
         Stock, and the denominator of which shall be the sum of the number of
         shares of Common Stock outstanding on such record date and the number
         of additional shares of Common Stock offered for subscription or
         purchase (or into which the convertible securities so offered are
         convertible) or (ii) in the event the Subscription Price is equal to
         or higher than the current market price but is less than the Exercise
         Price, the price determined by multiplying the Exercise Price in
         effect immediately prior to the date of issuance by a fraction, the
         numerator of which shall be the sum of the number of shares
         outstanding on the record date mentioned below and the number of
         additional shares of Common Stock which the aggregate offering price
         of the total number of shares of Common Stock so offered (or the
         aggregate conversion price of the convertible securities so offered)
         would purchase at the Exercise Price in effect immediately prior to
         the date of such issuance, and the denominator of which shall be the
         sum of the number of shares of Common Stock outstanding on the record
         date mentioned below and the number of additional shares of Common
         Stock offered for subscription or purchase (or into which the
         convertible securities so offered are convertible).  Such adjustment
         shall be made successively whenever such rights or warrants are issued
         and shall become effective immediately after the record date for the
         determination of shareholders





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         entitled to receive such rights or warrants; and to the extent that
         shares of Common Stock are not delivered (or securities convertible
         into Common Stock are not delivered) after the expiration of such
         rights or warrants the Exercise Price shall be readjusted to the
         Exercise Price which would then be in effect had the adjustments made
         upon the issuance of such rights or warrants been made upon the basis
         of delivery of only the number of shares of Common Stock (or
         securities convertible into Common Stock) actually delivered.

                 (3)      In case the Company shall hereafter distribute to the
         holders of its Common Stock evidences of its indebtedness or assets
         (excluding cash dividends or distributions and dividends or
         distributions referred to in Subsection (1) above) or subscription
         rights or warrants (excluding those referred to in Subsection (2)
         above), then in each such case the Exercise Price in effect thereafter
         shall be determined by multiplying the Exercise Price in effect
         immediately prior thereto by a fraction, the numerator of which shall
         be the total number of shares of Common Stock outstanding multiplied
         by the current market price per share of Common Stock (as defined in
         Subsection (8) below), less the fair market value (as determined by
         the Company's Board of Directors) of said assets or evidences of
         indebtedness so distributed or of such rights or warrants, and the
         denominator of which shall be the total number of shares of Common
         Stock outstanding multiplied by such current market price per share of
         Common Stock.  Such adjustment shall be made successively whenever
         such a record date is fixed.  Such adjustment shall be made whenever
         any such distribution is made and shall become effective immediately
         after the record date for the determination of shareholders entitled
         to receive such distribution.

                 (4)      In case the Company shall issue shares of its Common
         Stock [excluding shares issued (i) in any of the transactions
         described in Subsection (1) above, (ii) upon exercise of options
         granted to the Company's employees under a plan or plans adopted by
         the Company's Board of Directors and approved by its shareholders, if
         such shares would otherwise be included in this Subsection (4), (but
         only to the extent that the aggregate number of shares excluded hereby
         and issued after the date hereof, shall not exceed 5% of the Company's
         Common Stock outstanding at the time of any issuance), (iii) upon
         exercise of options and warrants outstanding at March 13, 1997, and
         this Warrant (iv) to shareholders of any corporation which merges into
         the Company in proportion to their stock holdings of such corporation
         immediately prior to such merger, upon such merger, or (v) issued in a
         bona fide public offering pursuant to a firm commitment underwriting,
         but only if no adjustment is required pursuant to any other specific
         subsection of this Section (f) (without regard to Subsection (9)
         below) with respect to the transaction giving rise to such rights] for
         a consideration per share (the "Offering Price") less than the current
         market price per share [as defined in Subsection (8) below] on the
         date the Company fixes the offering price of such additional shares or
         less than the Exercise Price, the





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         Exercise Price shall be adjusted immediately thereafter so that it
         shall equal the lower of (i) the price determined by multiplying the
         Exercise Price in effect immediately prior thereto by a fraction, the
         numerator of which shall be the sum of the number of shares of Common
         Stock outstanding immediately prior to the issuance of such additional
         shares and the number of shares of Common Stock which the aggregate
         consideration received [determined as provided in Subsection (7)
         below] for the issuance of such additional shares would purchase at
         such current market price per share of Common Stock, and the
         denominator of which shall be the number of shares of Common Stock
         outstanding immediately after the issuance of such additional shares
         or (ii) in the event the Offering Price is equal to or higher than the
         current market price per share but less than the Exercise Price, the
         price determined by multiplying the Exercise Price in effect
         immediately prior to the date of issuance by a fraction, the numerator
         of which shall be the number of shares of Common Stock outstanding
         immediately prior to the issuance of such additional shares and the
         number of shares of Common Stock which the aggregate consideration
         received [determined as provided in subsection (7) below] for the
         issuance of such additional shares would purchase at the Exercise
         Price in effect immediately prior to the date of such issuance, and
         the denominator of which shall be the number of shares of Common Stock
         outstanding immediately after the issuance of such additional shares.
         Such adjustment shall be made successively whenever such an issuance
         is made.

                 (5)      In case the Company shall issue any securities
         convertible into or exchangeable for its Common Stock [excluding
         securities issued in transactions described in Subsections (2) and (3)
         above] for a consideration per share of Common Stock (the "Conversion
         Price") initially deliverable upon conversion or exchange of such
         securities [determined as provided in Subsection (7) below] less than
         the current market price per share [as defined in Subsection (8) below]
         in effect immediately prior to the issuance of such securities, or less
         than the Exercise Price, the Exercise Price shall be adjusted
         immediately thereafter so that it shall equal the lower of (i) the
         price determined by multiplying the Exercise Price in effect
         immediately prior thereto by a fraction, the numerator of which shall
         be the sum of the number of shares of Common Stock outstanding
         immediately prior to the issuance of such securities and the number of
         shares of Common Stock which the aggregate consideration received
         [determined as provided in Subsection (7) below] for such securities
         would purchase at such current market price per share of Common Stock,
         and the denominator of which shall be the sum of the number of shares
         of Common Stock outstanding immediately prior to such issuance and the
         maximum number of shares of Common Stock of the Company deliverable
         upon conversion of or in exchange for such securities at the initial
         conversion or exchange price or rate or (ii) in the event the
         Conversion Price is equal to or higher than the current market price
         per share but less than the Exercise Price, the price determined by
         multiplying the Exercise Price in effect immediately prior to the date
         of issuance by a fraction, 



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         the numerator of which shall be the sum of the number of shares
         outstanding immediately prior to the issuance of such securities and
         the number of shares of Common Stock which the aggregate consideration
         received [determined as provided in subsection (7) below] for such
         securities would purchase at the Exercise Price in effect immediately
         prior to the date of such issuance, and the denominator of which shall
         be the sum of the number of shares of Common Stock outstanding
         immediately prior to the issuance of such securities and the maximum
         number of shares of Common Stock of the Company deliverable upon
         conversion of or in exchange for such securities at the initial
         conversion or exchange price or rate.  Such adjustment shall be made
         successively whenever such an issuance is made.

                 (6)      Whenever the Exercise Price payable upon exercise of
         each Warrant is adjusted pursuant to Subsections (1), (2), (3), (4)
         and (5) above, the number of Shares purchasable upon exercise of this
         Warrant shall simultaneously be adjusted by multiplying the number of
         Shares initially issuable upon exercise of this Warrant by the
         Exercise Price in effect on the date hereof and dividing the product
         so obtained by the Exercise Price, as adjusted.

                 (7)      For purposes of any computation respecting
         consideration received pursuant to Subsections (4) and (5) above, the
         following shall apply:

                          (A)     in the case of the issuance of shares of
                 Common Stock for cash, the consideration shall be the amount
                 of such cash, provided that in no case shall any deduction be
                 made for any commissions, discounts or other expenses incurred
                 by the Company for any underwriting of the issue or otherwise
                 in connection therewith;

                          (B)     in the case of the issuance of shares of
                 Common Stock for a consideration in whole or in part other
                 than cash, the consideration other than cash shall be deemed
                 to be the fair market value thereof as determined in good
                 faith by the Board of Directors of the Company (irrespective
                 of the accounting treatment thereof), whose determination
                 shall be conclusive; and

                          (C)     in the case of the issuance of securities
                 convertible into or exchangeable for shares of Common Stock,
                 the aggregate consideration received therefor shall be deemed
                 to be the consideration received by the Company for the
                 issuance of such securities plus the additional minimum
                 consideration, if any, to be received by the Company upon the
                 conversion or exchange thereof [the consideration in each case
                 to be determined in the same manner as provided in clauses (A)
                 and (B) of this Subsection (7)].





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                 (8)      For the purpose of any computation under Subsections
         (2), (3), (4) and (5) above, the current market price per share of
         Common Stock at any date shall be determined in the manner set forth
         in Section (c) hereof except that the current market price per share
         shall be deemed to be the higher of (i) the average of the prices for
         30 consecutive business days before such date or (ii) the price on the
         business day immediately preceding such date.

                 (9)      No adjustment in the Exercise Price shall be required
         unless such adjustment would require an increase or decrease of at
         least five cents ($0.05) in such price; provided, however, that any
         adjustments which by reason of this Subsection (9) are not required to
         be made shall be carried forward and taken into account in any
         subsequent adjustment required to be made hereunder.  All calculations
         under this Section (f) shall be made to the nearest cent or to the
         nearest one-hundredth of a share, as the case may be.  Anything in
         this Section (f) to the contrary notwithstanding, the Company shall be
         entitled, but shall not be required, to make such changes in the
         Exercise Price, in addition to those required by this Section (f), as
         it shall determine, in its sole discretion, to be advisable in order
         that any dividend or distribution in shares of Common Stock, or any
         subdivision, reclassification or combination of Common Stock,
         hereafter made by the Company shall not result in any Federal Income
         tax liability to the holders of Common Stock or securities convertible
         into Common Stock (including Warrants).

                 (10)     Whenever the Exercise Price is adjusted, as herein
         provided, the Company shall promptly but no later than 10 days after
         any request for such an adjustment by the Holder, cause a notice
         setting forth the adjusted Exercise Price and adjusted number of
         Shares issuable upon exercise of each Warrant, and, if requested,
         information describing the transactions giving rise to such
         adjustments, to be mailed to the Holders at their last addresses
         appearing in the Warrant Register, and shall cause a certified copy
         thereof to be mailed to its transfer agent, if any.  In the event the
         Company does not provide the Holder with such notice and information
         within 10 days of a request by the Holder, then notwithstanding the
         provisions of this Section (f), the Exercise Price shall be
         immediately adjusted to equal the lowest Offering Price, Subscription
         Price or Conversion Price, as applicable, since the date of this
         Warrant, and the number of shares issuable upon exercise of this
         Warrant shall be adjusted accordingly.  The Company may retain a firm
         of independent certified public accountants selected by the Board of
         Directors (who may be the regular accountants employed by the Company)
         to make any computation required by this Section (f), and a
         certificate signed by such firm shall be conclusive evidence of the
         correctness of such adjustment.

                 (11)     In the event that at any time, as a result of an
         adjustment made pursuant to Subsection (1) above, the Holder of this
         Warrant thereafter shall





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         become entitled to receive any shares of the Company, other than
         Common Stock, thereafter the number of such other shares so receivable
         upon exercise of this Warrant shall be subject to adjustment from time
         to time in a manner and on terms as nearly equivalent as practicable
         to the provisions with respect to the Common Stock contained in
         Subsections (1) to (9), inclusive above.

                 (12)     Irrespective of any adjustments in the Exercise Price
         or the number or kind of shares purchasable upon exercise of this
         Warrant, Warrants theretofore or thereafter issued may continue to
         express the same price and number and kind of shares as are stated in
         the similar Warrants initially issuable pursuant to this Agreement.

         (g)     OFFICER'S CERTIFICATE.  Whenever the Exercise Price shall be
adjusted as required by the provisions of the foregoing Section, the Company
shall forthwith file in the custody of its Secretary or an Assistant Secretary
at its principal office and with its stock transfer agent, if any, an officer's
certificate showing the adjusted Exercise Price determined as herein provided,
setting forth in reasonable detail the facts requiring such adjustment,
including a statement of the number of additional shares of Common Stock, if
any, and such other facts as shall be necessary to show the reason for and the
manner of computing such adjustment.  Each such officer's certificate shall be
made available at all reasonable times for inspection by the holder or any
holder of a Warrant executed and delivered pursuant to Section (a) and the
Company shall, forthwith after each such adjustment, mail a copy by certified
mail of such certificate to the Holder or any such holder.

         (h)     NOTICES TO WARRANT HOLDERS.  So long as this Warrant shall be
outstanding, (i) if the Company shall pay any dividend or make any distribution
upon the Common Stock or (ii) if the Company shall offer to the holders of
Common Stock for subscription or purchase by them any share of any class or any
other rights or (iii) if any capital reorganization of the Company,
reclassification of the capital stock of the Company, consolidation or merger
of the Company with or into another corporation, sale, lease or transfer of all
or substantially all of the property and assets of the Company to another
corporation, or voluntary or involuntary dissolution, liquidation or winding up
of the Company shall be effected, then in any such case, the Company shall
cause to be mailed by certified mail to the Holder, at least fifteen days prior
the date specified in (x) or (y) below, as the case may be, a notice containing
a brief description of the proposed action and stating the date on which (x) a
record is to be taken for the purpose of such dividend, distribution or rights,
or (y) such reclassification, reorganization, consolidation, merger,
conveyance, lease, dissolution, liquidation or winding up is to take place and
the date, if any is to be fixed, as of which the holders of Common Stock or
other securities shall receive cash or other property deliverable upon such
reclassification, reorganization, consolidation, merger, conveyance,
dissolution, liquidation or winding up.

         (i)     RECLASSIFICATION, REORGANIZATION OR MERGER.  In case of any
reclassification, capital reorganization or other change of outstanding shares
of Common





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Stock of the Company, or in case of any consolidation or merger of the Company
with or into another corporation (other than a merger with a subsidiary in
which merger the Company is the continuing corporation and which does not
result in any reclassification, capital reorganization or other change of
outstanding shares of Common Stock of the class issuable upon exercise of this
Warrant) or in case of any sale, lease or conveyance to another corporation of
the property of the Company as an entirety, the Company shall, as a condition
precedent to such transaction, cause effective provisions to be made so that
the Holder shall have the right thereafter by exercising this Warrant at any
time prior to the expiration of the Warrant, to purchase the kind and amount of
shares of stock and other securities and property receivable upon such
reclassification, capital reorganization and other change, consolidation,
merger, sale or conveyance by a holder of the number of shares of Common Stock
which might have been purchased upon exercise of this Warrant immediately prior
to such reclassification, change, consolidation, merger, sale or conveyance.
Any such provision shall include provision for adjustments which shall be as
nearly equivalent as may be practicable to the adjustments provided for in this
Warrant.  The foregoing provisions of this Section (i) shall similarly apply to
successive reclassifications, capital reorganizations and changes of shares of
Common Stock and to successive consolidations, mergers, sales or conveyances.
In the event that in connection with any such capital reorganization or
reclassification, consolidation, merger, sale or conveyance, additional shares
of Common Stock shall be issued in exchange, conversion, substitution or
payment, in whole or in part, for a security of the Company other than Common
Stock, any such issue shall be treated as an issue of Common Stock covered by
the provisions of Subsection (1) of Section (f) hereof.

         (j)     REGISTRATION UNDER THE SECURITIES ACT OF 1933.

                 (1)      The Company shall advise the Holder of this Warrant
         or of the Warrant Shares or any then holder of Warrants or Warrant
         Shares (such persons being collectively referred to herein as
         "holders") by written notice at least four weeks prior to the filing
         of any registration statement or post-effective amendment thereto
         under the Securities Act of 1933 (the "Act") covering securities of
         the Company and will for a period of five years, commencing on the
         initial closing of the Private Placement, upon the request of any such
         holder, include in any such registration statement such information as
         may be required to permit a public offering of the Warrant Shares. The
         Company shall supply prospectuses and other documents as the Holder
         may request in order to facilitate the public sale or other
         disposition of the Warrant Shares, qualify the Warrant Shares for sale
         in such states as any such holder designates and do any and all other
         acts and things which may be necessary or desirable to enable such
         Holders to consummate the public sale or other disposition of the
         Warrant Shares, and furnish indemnification in the manner as set forth
         in Subsection (3)(C) of this Section (j).  Such holders shall furnish
         information and indemnification as set forth in Subsection (3)(C) of
         this Section (j), except that the maximum amount which may be
         recovered from the Holder shall be limited to the amount of proceeds
         received by the Holder from the sale of the Warrant Shares.





                                       11
<PAGE>   13
                 (2)      If any majority holder (as defined in Subsection (4)
         of this Section (j) below) shall give notice to the Company at any
         time during the five year period commencing on the initial closing of
         the Private Placement to the effect that such holder contemplates (i)
         the transfer of all or any part of his or its Warrants and/or Warrant
         Shares, or (ii) the exercise and/or conversion of all or any part of
         his or its Warrants and the transfer of all or any part of the
         Warrants and/or Warrant Shares under such circumstances that a public
         offering (within the meaning of the Act) of Warrant Shares will be
         involved, and desires to register under the Act the Warrant Shares,
         then the Company shall, within two weeks after receipt of such notice,
         file a registration statement on Form S-1 or such other form as the
         holder requests, pursuant to the Act, to the end that the Warrant
         Shares may be sold under the Act as promptly as practicable thereafter
         and the Company will use its best efforts to cause such registration
         to become effective and continue to be effective (current) (including
         the taking of such steps as are necessary to obtain the removal of any
         stop order) until the holder has advised that all of the Warrant
         Shares have been sold; provided that such holder shall furnish the
         Company with appropriate information (relating to the intentions of
         such holders) in connection therewith as the Company shall reasonably
         request in writing.  In the event the registration statement is not
         declared effective under the Act prior to March 13, 2002, the Company
         shall extend the expiration date of the Warrants to a date not less
         than 90 days after the effective date of such registration statement.
         The holder may, at its option, request the registration of the Warrant
         Shares in a registration statement made by the Company as contemplated
         by Subsection (1) of this Section (j) or in connection with a request
         made pursuant to Subsection (2) of this Section (j) prior to the
         acquisition of the Warrant Shares upon exercise of the Warrants and
         even though the holder has not given notice of exercise of the
         Warrants.  If the Company determines to include securities to be sold
         by it in any registration statement originally requested pursuant to
         this Subsection (2) of this Section (j), such registration shall
         instead be deemed to have been a registration under Subsection (1) of
         this Section (j) and not under Subsection (2) of this Subsection (j).
         The holder may thereafter at its option, exercise the Warrants at any
         time or from time to time subsequent to the effectiveness under the
         Act of the registration statement in which the Warrant Shares were
         included.

                 (3)      The following provision of this Section (j) shall
         also be applicable:

                          (A)     Within ten days after receiving any such
                 notice pursuant to Subsection (2) of this Section (j), the
                 Company shall give notice to the other holders of Warrants and
                 Warrant Shares, advising that the Company is proceeding with
                 such registration statement and offering to include therein
                 Warrant Shares of such other holders, provided that they shall
                 furnish the Company with such appropriate information
                 (relating to the intentions of such holders) in connection
                 therewith as the Company shall





                                       12
<PAGE>   14
                 reasonably request in writing. Following the effective date of
                 such registration, the Company shall upon the request of any
                 owner of  Warrant Shares forthwith supply such a number of
                 prospectuses meeting the requirements of the Act, as shall be
                 requested by such owner to permit such holder to make a public
                 offering of all Warrant Shares from time to time offered or
                 sold to such holder, provided that such holder shall from time
                 to time furnish the Company with such appropriate information
                 (relating to the intentions of such holder) in connection
                 therewith as the Company shall request in writing.  The
                 Company shall also use its best efforts to qualify the Warrant
                 Shares for sale in such states as such majority holder shall
                 designate.

                          (B)     The Company shall bear the entire cost and
                 expense of any registration of securities initiated by it
                 under Subsection (1) of this Section (j) notwithstanding that
                 Warrant Shares subject to this Warrant may be included in any
                 such registration.  The Company shall also comply with one
                 request for registration made by the majority holder pursuant
                 to Subsection (2) of this Section (j) at its own expense and
                 without charge to any holder of any Warrants and/or Warrant
                 Shares; and the Company shall comply with one additional
                 request made by the majority holder pursuant to Subsection (2)
                 of this Section (j) (and not deemed to be pursuant to
                 Subsection (1) of this Section (j)) at the sole expense of
                 such majority holder.  Any holder whose Warrant Shares are
                 included in any such registration statement pursuant to this
                 Section (j) shall, however, bear the fees of his own counsel
                 and any registration fees, transfer taxes or underwriting
                 discounts or commissions applicable to the Warrant Shares sold
                 by him pursuant thereto.

                          (C)     The Company shall indemnify and hold harmless
                 each such holder and each underwriter, within the meaning of
                 the Act, who may purchase from or sell for any such holder any
                 Warrants and/or Warrant Shares from and against any and all
                 losses, claims, damages and liabilities caused by any untrue
                 statement or alleged untrue statement of a material fact
                 contained in any registration statement under the Act or any
                 prospectus included therein required to be filed or furnished
                 by reason of this Section (j) or caused by any omission or
                 alleged omission to state therein a material fact required to
                 be stated therein or necessary to make the statements therein
                 not misleading, except insofar as such losses, claims, damages
                 or liabilities are caused by any such untrue statement or
                 alleged untrue statement or omission or alleged omission based
                 upon information furnished or required to be furnished in
                 writing to the Company by such holder or underwriter expressly
                 for use therein, which indemnification shall include each
                 person, if any, who controls any such underwriter within the
                 meaning of such Act provided, however, that the





                                       13
<PAGE>   15
                 Company will not be liable in any such case to the extent that
                 any such loss, claim, damage or liability arises out of or is
                 based upon an untrue statement or alleged untrue statement or
                 omission or alleged omission made in said registration
                 statement, said preliminary prospectus, said final prospectus
                 or said amendment or supplement in reliance upon and in
                 conformity with written information furnished by such Holder
                 or any other Holder, specifically for use in the preparation
                 thereof.

                          (D)     Neither the giving of any notice by any such
                 majority holder nor the making of any request for prospectuses
                 shall impose such majority holder or owner making such request
                 any obligation to sell any Warrants and/or Warrant Shares, or
                 exercise any Warrants.

                 (4)      The term "majority holder" as used in this Section
         (j) shall include any owner or combination of owners of Warrants or
         Warrant Shares in any combination if the holdings of the aggregate
         amount of:

                          (i)     the Warrants held by him or among them, plus

                          (ii)    the Warrants which he or they would be
                 holding if the Warrants for the Warrant Shares owned by him or
                 among them had not been exercised,

         would constitute a majority of the Warrants originally issued.

         The Company's agreements with respect to Warrants or Warrant Shares in
this Section (j) shall continue in effect regardless of the exercise and
surrender of this Warrant.

                                 ACCUMED INTERNATIONAL, INC.

                                 By  /s/ Leonard R. Prange
                                     -----------------------------------
[SEAL]


Dated:  March 13, 1997

Attest:

/s/ Joyce L. Wallach
--------------------------
Secretary





                                       14
<PAGE>   16

                                 PURCHASE FORM


                                        Dated ____________, 19__

         The undersigned hereby irrevocably elects to exercise the within
Warrant to the extent of purchasing _______ shares of Common Stock and hereby
makes payment of _______ in payment of the actual exercise price thereof.

                                ________________

                     INSTRUCTIONS FOR REGISTRATION OF STOCK

Name ________________________________
(Please typewrite or print in block letters)


Address ______________________________


Signature ____________________________





                                       15
<PAGE>   17
                                ASSIGNMENT FORM

         FOR VALUE RECEIVED, ______________ hereby sells, assigns and transfers
unto


Name _____________________________
(Please typewrite or print in block letters)


Address ____________________________

the right to purchase Common Stock represented by this Warrant to the extent of
______ shares as to which such right is exercisable and does hereby irrevocably
constitute and appoint ___________ as attorney, to transfer the same on the
books of the Company with full power of substitution in the premises.

Date ____________, 19__

Signature ___________________