Department of Gastroenterology and Hepatology;
Okayama University Graduate School of Medicine;
Dentistry and Pharmaceutical Sciences;
Okayama 700-8558;
Japan;
Second Department of Internal Medicine;
Wakayama Medical University;
Wakayama 641-0012;
Japan;
Department of Endoscopy;
Okayama University Graduate School of Medicine;
Dentistry and Pharmaceutical Sciences;
Okayama 700-8558;
Japan;