1. Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Japan
2. Department of Pathology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Japan
3. Center for Graduate Medical Education, Okayama University Hospital, Japan
4. Department of Nephrology, Rheumatology, Endocrinology, and Metabolism, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Japan
5. Department of Practical Gastrointestinal Endoscopy, Okayama University Hospital, Japan