1. Department of Gastroenterology and Hepatology; National Center for Global Health and Medicine; Tokyo Japan
2. Department of Gastroenterology; Graduate School of Medicine; The University of Tokyo; Tokyo Japan
3. Ohta Nishinouchi Hospital; Koriyama Japan
4. The Research Center for Hepatitis and Immunology; National Center for Global Health and Medicine; Kohnodai Hospital; Chiba Japan
5. Department of Gastroenterology and Hepatology; National Center for Global Health and Medicine; Kohnodai Hospital; Chiba Japan