1. Department of Gastroenterology, Affiliated Hospital of Xi’an Jiaotong University, 277 West Yanta Road, Xi’an, Shaanxi, China
2. Department of Pathology, General Hospital of Ningxia Medical University, Ningxia, China
3. Department of Gastroenterology, General Hospital of Ningxia Medical University, Ningxia, China
4. Department of Radiology, General Hospital of Ningxia Medical University, Ningxia, China