1. School of Medicine, Southwest Jiaotong University, The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, Chengdu, PR China
2. Department of Gastroenterology, The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, Chengdu, PR China
3. North Sichuan Medical College, Nanchong, PR China