[1] JOHN RADCLIFFE HOSP,DEPT HAEMATOL,OXFORD OX3 9DU,ENGLAND
[2] UNIV MILAN,A BIANCHI BONOMI HAEMOPHILIA & THROMBOSIS CTR,I-20122 MILAN,ITALY
[3] JOHN RADCLIFFE HOSP,DEPT MATERN,OXFORD OX3 9DU,ENGLAND
[4] JOHN RADCLIFFE HOSP,NUFFIELD DEPT PATHOL,OXFORD OX3 9DU,ENGLAND