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EP 0 619 844 A1

(12)

(43) Date of publication: 19.10.1994 Bulletin 1994/42 (21) Application number: 92906497.0 (22) Date of filing: 12.03.1992

(51) International Patent Classification (IPC):  A01H 5/ 00( . ) C12N 15/ 82( . ) C12N 15/ 52( . ) (86) International application number: PCT/GB1992/000442 (87) International publication number: WO 1992/016635 (01.10.1992 Gazette 1992/25)

(84) Designated Contracting States: AT BE DE DK FR GB IT LU MC NL SE (30) Priority: 14.03.1991 GB 19910054205 (71) Applicant: ZENECA LIMITED London W1Y 6LN (GB)

(72) Inventors: BIRD, Colin, Roger Berkshire RG12 1YT (GB) GRIERSON, Donald Loughbrough LE12 9SJ (GB) RAY, John, Anthony Bracknell RG12 4XX (GB) SCHUCH, Wolgang, Walter 14 Greenfinch Close Crowthorne Berkshire RG11 6TZ (GB) (74) Representative: Roberts, Timothy Wace, et al  ICI Group Patents Services Dept. PO Box 6 Shire Park Bessemer Road Welwyn Garden City, Herts, AL7 1HD Welwyn Garden City, Herts, AL7 1HD (GB)