(19)

(11)

EP 0 817 599 A1

(12)

(43) Date of publication: 14.01.1998 Bulletin 1998/03 (21) Application number: 96907602.0 (22) Date of filing: 21.03.1996

(51) International Patent Classification (IPC):  A61F 2/ 06( . ) A61F 2/ 90( . ) (86) International application number: PCT/GB1996/000676 (87) International publication number: WO 1996/029028 (26.09.1996 Gazette 1996/43)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 21.03.1995 GB 19950005721 (71) Applicant: UNIVERSITY COLLEGE LONDON London WC1E 6BT (GB)	(72) Inventors: GRASS, Anthony, James Chesham Bois, Bucks HP6 5PQ (GB) ADISESHIAH, Mohan London W1M 7DG (GB) (74) Representative: Moir, Michael Christopher, et al  Mathys & Squire 100 Gray's Inn Road London WC1X 8AL London WC1X 8AL (GB)