1. Department of Internal Medicine, Division of Gastroenterology; Nippon Medical School Chiba Hokusoh Hospital; Chiba Japan
2. Department of Internal Medicine, Division of Gastroenterology and Hepatology; Nippon Medical School; Tokyo Japan
3. Core Research Facilities for Basic Science; The Jikei University School of Medicine; Tokyo Japan
4. Department of Internal Medicine, Division of Hepatology and Gastroenterology; Tokyo Medical University, Ibaraki Medical Center; Ibaraki Japan
5. Department of Internal Medicine, Division of Gastroenterology and Hepatology; Otakanomori Hospital; Chiba Japan
6. Department of Internal Medicine, Division of Gastroenterology and Hepatology; Shinmatsudo Central General Hospital; Chiba Japan
7. Department of Internal Medicine, Division of Gastroenterology; Kikkoman General Hospital; Chiba Japan
8. Department of Internal Medicine, Division of Gastroenterology and Hepatology; Tokyo Metropolitan Bokutoh Hospital; Tokyo Japan
9. Department of Gastroenterology; Ogaki Municipal Hospital; Gifu Japan
10. Department of Nursing; Ogaki Women's College; Gifu Japan
11. Department of Virology and Liver Unit; Nagoya City University, Graduate School of Medical Sciences; Aichi Japan