1. Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
2. Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
3. Institute of Pharmacology, National Yang-Ming University School of Medicine, Taipei, Taiwan
4. Division of General Medicine, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
5. Endoscopy Center for Diagnosis and Treatment, Taipei Veterans General Hospital, Taipei, Taiwan
6. Division of Gastroenterology, Department of Medicine, Cheng Hsin General Hospital, Taipei, Taiwan