1. Division of Gastroenterology and Hepatology; Department of Internal Medicine; National Defense Medical College; Saitama Japan
2. Division of Gastroenterology and Hepatology; Department of Internal Medicine; Keio University School of Medicine; Tokyo Japan
3. Department of Pathology; Kawasaki Municipal Hospital; Kanagawa Japan
4. Health Center; Keio University School of Medicine; Tokyo Japan
5. Graduate School of Pharmaceutical Sciences; Keio University Faculty of Pharmacy; Tokyo Japan