1. U348 INSERM, 8, Rue Guy Patin, Hôpital Lariboisière, 75475 Paris Cédex 10, France.
2. National Institute of Haematology and Blood Transfusion, Budapest, Hungary.
3. U275 INSERM, Faculte des Sciences, Orsay, France.
4. U91 INSERM, Hôpital Henri Mondor, Creteil, France.
5. Theodor Kocher Institute, University of Bern, Switzerland.
6. Laboratorium voor Fysiologie, Katholieke Universiteit Leuven, Belgium.