[1] Univ Bonn, House Expt Therapy, D-53105 Bonn, Germany
[2] Kyoto Univ, Grad Sch Med, Dept Surg Gastroenterol, Kyoto, Japan
[3] Univ Amsterdam, Acad Med Ctr, Surg Lab, NL-1105 AZ Amsterdam, Netherlands
[4] Univ Bonn, Inst Pathol, D-5300 Bonn, Germany
[5] Akita Univ, Sch Med, Dept Surg Gastroenterol, Akita 010, Japan
[6] Univ Bonn, Dept Surg, Div Surg Res, D-5300 Bonn, Germany