[1] UNIV COLOGNE,KLIN & POLIKLIN VISCERAL & GEFASSCHIRURG,D-50931 COLOGNE,GERMANY
[2] TECH UNIV MUNICH,CHIRURG KLIN & POLIKLIN,D-8000 MUNICH,GERMANY
[3] TECH UNIV MUNICH,MED KLIN 2,D-8000 MUNICH,GERMANY
[4] TECH UNIV MUNICH,INST ALLGEMEINE PATHOL & PATHOL ANAT,D-8000 MUNICH,GERMANY