1. School of Medicine, Southwest Jiaotong University, the Affiliated Hospital of Southwest Jiaotong University, the Third People's Hospital of Chengdu, Chengdu, China.
2. Department of Gastroenterology, the Affiliated Hospital of Southwest Jiaotong University, the Third People's Hospital of Chengdu, Chengdu, China.
3. Medical Research Center, the Third People's Hospital of Chengdu, the Affiliated Hospital of Southwest Jiaotong University, the Second Chengdu Affiliated Hospital of Chongqing Medical University, Chengdu, Sichuan, China.