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                                                                EXHIBIT 10.11C-2



February 25, 1997

GDK, Inc.
c/o Caxton Corporation
667 Madison Ave, 10th Floor
New York, NY 10021

Attn:  Andy Waldman

Gentlemen:

In accordance with Section 13 of the Stock Purchase Warrant issued pursuant to
the Securities Purchase Agreement dated May 11, 1994, we hereby notify you that
the terms of your warrant have been adjusted such that rather than having the
right to purchase 117,154 shares at $3.521, you now have the right to purchase
124,232 shares at $3.319 each.  All other terms of the warrant agreement remain
in effect.

Please call me if you have any questions.

Very Truly Yours,

/s/ JOHN W. VARIAN
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John W. Varian
Vice President, Finance & CFO


JWV/cb