[1] Tohoku Univ Hosp, Div Gastroenterol, Aoba Ku, Sendai, Miyagi 9808574, Japan
[2] Tohoku Rosai Hosp, Dept Gastroenterol, Sendai, Miyagi 9808574, Japan
[3] Miyagi Canc Ctr, Dept Gastroenterol, Natori, Miyagi 9811293, Japan
[4] Tohoku Kosai Hosp, Dept Internal Med, Sendai, Miyagi 9800803, Japan
[5] Shirakawa Kosei Gen Hosp, Dept Internal Med, Shirakawa 9610005, Japan
[6] Ishinomaki Municipal Hosp, Dept Gastroenterol, Ishinomaki, Miyagi 9860835, Japan
[7] Osaki Citizen Hosp, Dept Gastroenterol, Furukawa, Miyagi 9896183, Japan
[8] Sendai Med Ctr, Dept Gastroenterol, Sendai, Miyagi 9838520, Japan
[9] Miyagi Social Insurance Hosp, Dept Internal Med, Sendai, Miyagi 9811103, Japan