1. Division of Gastroenterology, Department of Internal Medicine
2. Department of Internal Medicine; Hanamakionsen Hospital affiliated with Iwate Medical University; Hanamaki Japan
3. Department of Gastroenterology; Yamamotokumiai Hospital; Noshiro Japan
4. Department of Gastroenterology; Iwate Prefectural Miyako Hospital; Miyako
5. Department of Gastroenterology; Morioka Red Cross Hospital; Morioka Japan
6. Department of Gastroenterology; Iwate Prefectural Kuji Hospital; Kuji Japan
7. Department of Gastroenterology; Hachinohe Red Cross Hospital; Hachinohe Japan
8. Division of Molecular Diagnostic Pathology, Department of Pathology, School of Medicine; Iwate Medical University; Morioka