[1] Keio Univ, Sch Med, Dept Internal Med, Shinjuku Ku, Tokyo 1608582, Japan
[2] Keio Univ, Fac Pharm, Shinjuku Ku, Tokyo 1608582, Japan
[3] Keio Univ, Sch Med, Dept Internal Med, Div Gastroenterol & Hepatol, Tokyo 1608582, Japan
[4] Keio Univ, Sch Med, Dept Pathol, Tokyo 1608582, Japan
[5] Keio Univ, Sch Med, Dept Diagnost Radiol, Tokyo 1608582, Japan