Abstract
1 Division of Gastroenterology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
2 Department of Gastroenterology, St Luke's Medical Center, Quezon, The Philippines
3 Tohoku University School of Health Sciences and Comprehensive Research and Education Center for Planning of Drug Development and Clinical Evaluation, Sendai, Japan
4 Department of Internal Medicine, Mizusawa General Hospital, Iwate, Japan