1. Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Suita, Japan.
2. Department of Gastroenterological Surgery, Kawanishi City Hospital, Kawanishi, Japan.
3. Department of Therapeutics for Inflammatory Bowel Diseases, Graduate School of Medicine, Osaka University, Suita, Japan.
4. Department of Surgery, Osaka Police Hospital, Osaka, Japan.