1. Department of Pathology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
2. Department of General Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
3. Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
4. National Clinical Research Center for Digestive Disease, Beijing Friendship Hospital, Capital Medical University, Beijing, China
5. Clinical Laboratory Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China