1. Department of Gastroenterology, Changhai Hospital, Naval Medical University, Shanghai 200433, China
2. Shanghai Institute of Pancreatic Diseases, Shanghai, China
3. Department of Gastroenterology, The First Medical Center of Chinese People’s Liberation Army General Hospital, Beijing 100853, China.
4. Department of Gastroenterology, 987th Hospital of the Joint Logistics Support Force of the People's Liberation Army, Baoji, Shaanxi, China
5. Changhai Clinical Research Unit, Changhai Hospital, Naval Medical University, Shanghai 200433, China