[1] Takamatsu Hosp, Dept Surg Gastroenterol, Federat Publ Serv & Affiliated Personnel Aid Asso, 4-18 Tenjinmae, Takamatsu, Kagawa 7600018, Japan
[2] Kagawa Univ, Sch Med, Dept Gastroenterol, Takamatsu, Kagawa 7610793, Japan
[3] Kagawa Univ, Sch Med, Dept Neurol, Takamatsu, Kagawa 7610793, Japan