1. Department of CT, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
2. Department of Nursing, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
3. Department of Gastroenterology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
4. Department of Intervention, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
5. Department of Anatomy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China