1 Department of Gastrointestinal and Pediatric Surgery, Oslo University Hospital, P.O. Box 4950 Nydalen, N-0424 Oslo, Norway Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
2 Department of Gastrointestinal and Pediatric Surgery, Oslo University Hospital, Oslo, Norway.
3 Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
4 College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia.
5 Division of Surgery and Perioperative Medicine, Flinders Medical Centre, Bedford Park, SA, Australia.
6 Division of Digestive & Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA, USA.