[1] UNIV CALIF LOS ANGELES,CTR HLTH SCI,SCH MED,DEPT PHARMACOL,LOS ANGELES,CA 90024
[2] CNRS,INST EMBRYOL,F-94130 NOGENT SUR MARNE,FRANCE
[3] MIDDLESEX HOSP,SCH MED,DEPT ANAT & BIOL APPL MED,LONDON W1P 6DP,ENGLAND
[4] ARC,INST ANIM PHYSIOL,DEPT CELL BIOL,CAMBRIDGE CB2 4AT,ENGLAND
[5] UNIV GOTEBORG,DEPT PHYSIOL,S-40033 GOTEBORG,SWEDEN
[6] ST THOMAS HOSP & MED SCH,DEPT SURG,LONDON SE1 7EH,ENGLAND
[7] UNIV ABERDEEN,DEPT PATHOL,ABERDEEN AB9 2ZD,SCOTLAND
[8] JOHNS HOPKINS UNIV HOSP,WILMER OPHTHALMOL INST,BALTIMORE,MD 21205
[9] UNIV CHICAGO,DEPT ANAT,CHICAGO,IL 60637
[10] UNIV CHICAGO,DEPT PEDIAT,CHICAGO,IL 60637
[11] UNIV CHICAGO,COMM DEV BIOL,CHICAGO,IL 60637
[12] AUSTRALIAN NATL UNIV,JOHN CURTIN SCH MED RES,DEPT EXPTL PATHOL,CANBERRA,ACT 2601,AUSTRALIA
[13] MT VERNON HOSP,GRAY LAB,NORTHWOOD HA6 2RN,MIDDX,ENGLAND