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                                                                   Exhibit 10.19

                                  BIONEBRASKA, INC.
                           INCENTIVE STOCK OPTION AGREEMENT

       THIS OPTION AGREEMENT is made as of the _____ day of _______________,
199_, between BioNebraska, Inc., a Delaware corporation (the "Company"), and
________________________________________, an employee of the Company (the
"Optionee").

       The Company desires, by affording the Optionee an opportunity to purchase
shares of its Common Stock, of the par value of One Cent ($.01) per share (the
"Common Stock"), as hereinafter provided, to carry out the purpose of the 1993
Stock Plan of the Company, as amended in 1996 and approved by its shareholders
(the "Plan").

       THEREFORE, the parties hereby agree as follows:

       1.     GRANT OF OPTION.  The Company hereby grants to the Optionee the
right and option (hereinafter called the "Option") to purchase from the Company
all or any part of an aggregate amount of _______________ shares of the Common
Stock of the Company on the terms and conditions herein set forth.

       2.     PURCHASE PRICE.  The purchase price of the shares of the Common
Stock covered by this Option shall be $__________ per share.

       3.     TERM OF OPTION.  The term of the Option shall be for a period of
five (5) years from the date hereof (the "Option Date"), subject to earlier
termination as hereinafter provided.

       4.     EXERCISE OF OPTION.  During the first year the Option is
outstanding, it may not be exercised with respect to any of the Shares covered
hereby.  Thereafter, subject to the terms and conditions hereof, the Option may
be exercised as follows:

              (a)    From and after 12 months from the Option Date, the Option
       may be exercised as to _____ shares.

              (b)    From and after 24 months from the Option Date, the Option
       may be exercised as to an additional _____ shares.

              (c)    From and after 36 months from the Option Date, the Option
       may be exercised as to an additional _____ shares.

       5.     ADJUSTMENTS.  Notwithstanding any installment exercise provisions
of Section 4 above, this Option shall be exercisable in full, without regard to
any installment exercise



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provisions, for a period specified by the Company, but not to exceed sixty
(60) days, prior to the occurrence of any of the following events:  (i)
dissolution or liquidation of the Company other than in conjunction with a
bankruptcy of the Company or any similar occurrence, (ii) any merger,
consolidation, acquisition, separation, reorganization, or similar
occurrence, where the Company will not be the surviving entity or (iii) the
transfer of substantially all of the assets of the Company or 75% or more of
the outstanding Stock of the Company.

       6.     NON-TRANSFERABILITY.  The Option shall not be transferable
otherwise than by will or the laws of descent and distribution, and the Option
may be exercised, during the lifetime of the Optionee, only by the Optionee.

       7.     DEATH, DISABILITY OR RETIREMENT OF OPTIONEE.  If the Optionee's
employment with the Company shall terminate by reason of death, Disability or
Retirement (as those terms are defined in the Plan), the Option may be exercised
(to the extent that the Optionee shall have been entitled to do so at the date
of his termination of employment by reason of death, Disability or Retirement)
by the Optionee, his legal representative, or, in the case of death, by the
person to whom the Option is transferred by will or the applicable laws of
descent and distribution at any time within ninety (90) days after the
Optionee's termination of employment, but in no event later than the expiration
of the term specified in Section 3 hereof.

       8.     OTHER TERMINATION.  In the event the employment of the Optionee
shall be terminated for any reason other than death, Disability or Retirement,
any unexercised Option may be exercised by the Optionee to the extent it was
exercisable at such termination, but may not be exercised after ninety (90) days
of such termination or the expiration of the stated term of the option,
whichever period is the shorter; provided, however, that in the event of
termination for Cause (as that term is defined in the Plan), such Option shall
terminate immediately upon such termination of employment.  So long as the
Optionee shall continue to be an employee of the Company or one or more of its
subsidiaries, the Option shall not be affected by any change of duties or
position.  Nothing in this Option Agreement shall confer upon the Optionee any
right to continue in the employ of the Company or of any of its subsidiaries or
interfere in any way with the right of the Company or any such subsidiary to
terminate the employment of the Optionee at any time.

       9.     METHOD OF EXERCISING OPTION.  Subject to the terms and conditions
of this Option Agreement, the Option may be exercised by written notice to the
Secretary of the Company at the principal office of the Company.  Such notice
shall state the election to exercise the Option and the number of shares in
respect of which it is being exercised, and shall be signed by the person so
exercising the Option.  Such notice shall be accompanied by payment of the full
purchase price of such shares, which payment shall be made in cash or by check
or bank draft payable to the Company, or, provided such form of payment does not
result in a charge to earnings of the Company for financial accounting purposes,
by delivery of shares of Common Stock of the Company with a fair market value
equal to the purchase price or by a combination of cash and such shares, whose
fair market value shall equal the purchase price.  For purposes of


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this paragraph, the "fair market value" of the Common Stock of the Company
shall be established in the manner set forth in the Plan.  In the event the
Option shall be exercised by any person other than the Optionee, such notice
shall be accompanied by appropriate proof of such right of such person to
exercise the Option.

       10.    OPTION PLAN.  This Option is subject to certain additional terms
and conditions set forth in the Plan pursuant to which this Option has been
issued.  A copy of the Plan is on file with the Treasurer of the Company and by
acceptance hereof, Optionee agrees to and accepts this Option subject to the
terms of the Plan.  Except as otherwise defined herein, defined terms used in
this Agreement shall have the meaning ascribed thereto in the Plan.

       11.    DISPUTES.  As a condition of the granting of the Option herein
granted, the Optionee agrees, for the Optionee and the Optionee's personal
representatives, that any dispute or disagreement which may arise under or as a
result of or pursuant to this Agreement shall be determined by the Compensation
Committee of the Board of Directors of the Company, or the Board if there is no
such committee, in its sole discretion, and that any interpretation by said
Committee of the terms of this Agreement shall be final, binding and conclusive.

       12.    BINDING EFFECT.  This Agreement shall be binding upon the heirs,
executors, administrators and successors of the parties hereto.

       IN WITNESS WHEREOF, the Company and the Optionee have executed this
Agreement as of the date and year first above written.

                                          BIONEBRASKA, INC.



                                          By_________________________________
                                              Chairman of the Board and CEO


                                          ____________________________________
                                                 Optionee


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