Patents Reinstated Due to the Acceptance of a
                      Late Maintenance Fee From 05/15/98
   
Patent           Serial            Filing          Issue          Granted
Number           Number            Date            Date           Date

4,554,005        06/644,975        08/28/84        11/19/85       05/15/98
4,556,195        06/648,075        09/07/84        12/03/85       05/20/98
4,700,406        06/828,944        02/12/86        10/20/87       05/19/98
4,796,515        07/002,740        01/12/87        01/10/89       05/20/98
4,809,752        07/044,838        04/30/87        03/07/89       05/20/98
4,844,212        07/192,988        05/12/88        07/04/89       05/15/98
5,060,417        07/426,976        10/25/89        10/29/91       05/21/98
5,091,601        07/584,960        09/19/90        02/25/92       05/15/98
5,122,917        07/531,832        06/01/90        06/16/92       05/18/98
5,124,018        07/283,782        12/13/88        06/23/92       05/18/98
5,124,420        07/723,279        06/28/91        06/23/92       05/18/98
5,131,862        07/665,542        03/01/91        07/21/92       05/20/98
5,143,107        07/621,036        11/30/90        09/01/92       05/19/98
5,151,030        07/729,485        07/12/91        09/29/92       05/15/98
5,177,148        07/572,323        08/23/90        01/05/93       05/20/98
5,183,851        07/752,977        09/03/91        02/02/93       05/15/98
5,190,484        07/929,531        08/14/92        03/02/93       05/20/98
5,203,529        07/628,935        12/14/90        04/20/93       05/19/98
5,225,576        07/711,775        06/07/91        07/06/93       05/15/98
5,240,961        07/907,847        07/02/92        08/31/93       05/21/98
5,247,787        07/823,722        01/22/92        09/28/93       05/15/98
5,248,286        07/891,178        05/29/92        09/28/93       05/15/98
5,251,849        07/456,533        12/26/89        10/12/93       05/20/98
5,261,060        07/668,778        03/13/91        11/09/93       05/21/98
5,276,596        07/902,940        06/23/92        01/04/94       05/21/98