1 Department of Gastroenterology and Metabology, Ehime University Graduate School of Medicine, Shitsukawa 454, Toon, Ehime, 791-0295, Japan. masashih@m.ehime-u.ac.jp.
2 Department of Gastroenterology and Metabology, Ehime University Graduate School of Medicine, Shitsukawa 454, Toon, Ehime, 791-0295, Japan.
3 Department of Gastroenterology, National Hospital Organization Ehime Medical Center, Yokogawara 366, Toon, Ehime, 791-0281, Japan.