1. Department of Gastroenterology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
2. Xi'an Aerospace General Hospital, Xi'an, China
3. Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
4. Section of Gastroenterology, Sacramento Veterans Affairs Medical Center, Mather, California, USA
5. Department of Cardiology, Jinan Military General Hospital, Jinan, China
6. WEGO Medical System Company, Weihai, China