1. Gastrointestinal Motility Unit, Division of Gastroenterology, Kaohsiung Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, 833 Kaohsiung, Taiwan
2. Department of Hepatology, Hospital Selayang, Lebuh Raya Selayang-Kepong, Batu Caves, Selangor, Malaysia
3. Department of Surgery, Kaohsiung Chang Gung Memorial Hospital, 833 Kaohsiung, Taiwan