Changes in Von Willebrand factor in patients bitten by Bothrops snakes: Aura S. Kamiquti, R. A. Hutton, Katherine B. Matthews, Ida S. Sano-Martins,1J. L. C. Cardoso2 and R. D. G. Theakston3 (Haemophilia Centre and Haemostasis Unit, Royal Free Hospital, London, U.K., 1Haematology Dept and 2Vital Brazil Hospital, Institute Butantan, São Paulo, Brazil and 3Alistair Reid Venom Research Unit, Liverpool School of Tropical Medicine, Liverpool, U.K.)