PROMISSORY NOTE

         FOR VALUE RECEIVED,  Cheung  Laboratories,  Inc. (the "Company") hereby
ratifies  and  confirms  its  promise  of June 30,  1994 to pay to the  order of
Augustine Y. Cheung,  the sum of Fourty-Two  Thousand Six Hundred Sixty-Nine And
00/100 ($42,669.00)  Dollars,  together with interest thereon at the rate of 10%
per annum on the unpaid balance.

         Said principal and interest shall be due and payable December 31, 1999.

         The  Company  may prepay this note  without  penalty.  In the event any
payment  due  hereunder  is not paid  when  due,  the  entire  balance  shall be
immediately due upon demand of any holder.  Upon default,  the company shall pay
all  reasonable  attorney fees and costs  necessary  for the  collection of this
note.
         Signed this 9th day of December, 1996.
                                                       For the Company:

                                                       /s/Verle D. Blaha
                                                       Verle D. Blaha, President
                                                       Cheung Laboratories, Inc.

319383.001(B&F)                                    
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