NOTIFICATION OF ACCEPTANCE OF DELAYED PAYMENT OF MAINTENANCE FEE
                        (35 U.S.C. 41(c); 37 CFR 1.378)

   The patent(s) listed below are considered as not having expired but are
subject to the conditions set forth in 35 U.S.C. 41(c)(2), in view of the
Petition to Accept Late Payment of the maintenance fees which has been GRANTED
BY THE COMMISSIONER OF PATENTS AND TRADEMARKS, as provided for under 35 U.S.C.
41(c)(1) and 37 CFR 1.378.

                                                Application     Delayed Payment
Patent No.       Serial No.     Patent Date     Filing Date     Acceptance Date

Re. 32,452       06/831,521        07/07/87        02/20/86        02/28/95
(4,483,280)     (06/550,521)      (11/20/84)      (11/14/83)
4,490,415        07/248,256        07/10/90        09/20/88        02/27/95
4,519,992        06/613,892        05/28/85        05/24/84        02/27/95
4,550,026        06/466,489        10/29/85        02/15/83        02/28/95
4,569,779        06/688,588        02/11/86        01/03/85        02/27/95
4,576,925        06/701,563        03/18/86        02/14/85        02/28/95
4,580,670        06/563,773        04/08/86        12/21/83        02/28/95
4,617,121        06/772,310        10/14/86        09/04/85        02/28/95
4,798,387        07/004,294        01/17/89        01/05/87        02/27/95
4,810,000        07/115,849        03/07/89        11/02/87        02/17/95
4,882,799        07/207,299        11/28/89        06/15/88        02/28/95
4,883,538        07/231,372        11/28/89        08/08/88        02/27/95
4,900,251        07/187,735        02/13/90        04/29/88        02/17/95
4,900,726        07/262,613        02/13/90        10/26/88        02/27/95
4,901,779        07/207,175        02/20/90        06/15/88        02/28/95
4,906,831        07/301,104        03/06/90        01/25/90        02/28/95
4,907,060        07/056,650        03/06/90        06/02/87        02/27/95
4,917,832        07/310,061        04/17/90        02/10/89        02/28/95
4,919,777        07/066,770        04/24/90        06/25/87        02/28/95
4,922,822        07/283,501        05/08/90        12/12/88        02/28/95
4,924,041        07/343,308        05/08/90        04/26/89        02/28/95
4,925,931        07/219,499        05/15/90        07/14/88        02/28/95
4,942,874        07/301,772        07/24/90        01/26/89        02/28/95
4,951,755        07/401,182        08/28/90        08/31/89        02/17/95
4,955,102        07/269,075        09/11/90        11/09/88        02/28/95
4,960,446        07/353,979        10/02/90        05/19/89        02/28/95
4,968,396        07/304,187        11/06/90        01/30/89        02/17/95