1. Department of Gastroenterology, the Second Xiangya Hospital, Central South University, Changsha, China
2. Research Center of Digestive Disease, Central South University, Changsha, China
3. Department of Oncology, the Third Xiangya Hospital, Central South University, Changsha, China
4. Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China