[1] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Gastroenterol & Hepatol, Okayama, Japan
[2] Okayama Univ, Dept Gastroenterol & Hepatol, Okayama, Japan
[3] Hiroshima City Hiroshima Citizens Hosp, Hiroshima, Japan
[4] Kagawa Prefectural Cent Hosp, Takamatsu, Kagawa, Japan
[5] Sumitomo Besshi Hosp, Nihama City, Japan
[6] Kurashiki Cent Hosp, Kurashiki, Okayama, Japan