1. Department of Gastroenterology, PLA Strategic Support Force Characteristic Medical Center, Beijing, P. R. China
2. State Environmental Protection Key Laboratory of Environmental Sense Organ Stress and Health, PLA Strategic Support Force Characteristic Medical Center, Beijing, P. R. China
3. Department of Internal Medicine, The Hospital of the People's Liberation Army 63650 Corps, Malan, Xinjiang, P. R. China
4. Department of Pediatrics, The First Affiliated Hospital of Xi'an Medical University, Xi’an, Shaanxi, P. R. China
5. Department of Otorhinolaryngology Head and Neck Surgery, PLA Strategic Support Force Characteristic Medical Center, Beijing, P. R. China