1. Department of Gastroenterology and Hepatology, Kansai Medical University, 10-15 Fumisono Cho, Moriguchi, Osaka 570-8506, Japan
2. The Third Department of Internal Medicine, Division of Gastroenterology and Hepatology, Kansai Medical University, 2-3-1 Shinmachi, Hirakata, Osaka 573-1191, Japan