1. Division of Gastroenterology; Tohoku University Graduate School of Medicine; 1-1 Seiryo, Aoba Sendai 980-8574 Japan
2. Department of Surgery; Teikyo University School of Medicine; Tokyo Japan
3. Department of Emergency and Critical Care Medicine; Kimitsu Chuo Hospital; Chiba Japan
4. Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences; Kyushu University; Fukuoka Japan
5. Department of Surgical Oncology and Gastroenterological Surgery; Sapporo Medical University Graduate School of Medicine; Sapporo Japan
6. Department of Hemodialysis and Surgery; Clinical Research Center Kaken Hospital, International University of Health and Welfare; Chiba Japan
7. Department of Emergency and Critical Care Medicine; Nagoya University Graduate School of Medicine; Nagoya Japan
8. Otsu Municipal Hospital; Otsu Japan
9. Department of Surgery; National Hospital Organization Sendai Medical Center; Sendai Japan
10. Department of Healthcare Economics and Quality Management; Kyoto University Graduate School of Medicine; Kyoto Japan
11. Department of Surgery; Kumamoto Regional Medical Center; Kumamoto Japan
12. Department of Radiology, Graduate School of Medical Science; Kanazawa University; Ishikawa Japan
13. Critical Care and Emergency Center; Yokohama City University Medical Center; Yokohama Japan
14. General Internal Medicine; Japanese Red Cross Society Nagoya Daini Hospital; Nagoya Japan
15. Department of Gastroenterology; Ogaki Municipal Hospital; Ogaki Japan