[1] Free Univ Berlin, Klinikum Benjamin Franklin, Abt Innere Med Gastroenterol & Infektiol, D-12000 Berlin, Germany
[2] NIH, Cell Biol Sect, Bethesda, MD 20892 USA
[3] CHU Bichat, Serv Hepatogastroenterol, F-75877 Paris, France
[4] Yale Univ, Sch Med, Dept Surg, New Haven, CT 06520 USA
[5] Univ Uppsala Hosp, Dept Internal Med, Endocrine Unit, S-75185 Uppsala, Sweden
[6] Washington Univ, Sch Med, Sect Endocrine & Oncol Surg, St Louis, MO 63110 USA