[1] Duke Univ, Med Ctr, Duke Clin Res Inst, Durham, NC 27715 USA
[2] Hannover Med Sch, Div Gastroenterol & Hepatol, D-3000 Hannover, Germany
[3] Grp Hosp Pitie Salpetriere, F-75634 Paris, France
[4] Univ So Calif, Div Gastroenterol & Hepatol, Los Angeles, CA USA
[5] Hop Hotel Dieu, Serv Hepato Gastroenterol, Lyon, France
[6] Harvard Univ, Sch Med, Massachusetts Gen Hosp, Gastrointestinal Unit, Boston, MA 02115 USA
[7] Univ Texas, SW Med Ctr Dallas, Dallas, TX 75235 USA
[8] Schering Plough Res Inst, Kenilworth, NJ USA