1. Department of Infectious Diseases; Tokai University School of Medicine; Isehara Kanagawa 259-1193 Japan
2. Department of Gastroenterology; Tokai University School of Medicine; Isehara Kanagawa 259-1193 Japan
3. Sagami Research Laboratories; Wakamoto Pharmaceu. Co.; Kanagawa 258-0018 Japan
4. General Internal Medicine; Tokai University School of Medicine; Isehara Kanagawa 259-1193 Japan