1 National Yang-Ming University, School of Medicine, Taipei, Taiwan, ROC; Division of Gastroenterology & Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
2 National Yang-Ming University, School of Medicine, Taipei, Taiwan, ROC; Division of Gastroenterology & Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Endoscopic Center for Diagnosis and Therapy, Taipei Veterans General Hospital, Taipei, Taiwan, ROC. Electronic address: jcluo@vghtpe.gov.tw.