1. Department of Gastroenterology, General Hospital of Northern Theater Command, Shenyang, China
2. Graduate School, Dalian Medical University, Dalian, China
3. Section of Medical Service, General Hospital of Northern Theater Command, Shenyang, China
4. Graduate School, Shenyang Pharmaceutical University, Shenyang, China
5. Graduate School, China Medical University, Shenyang, China
6. Department of Gastroenterology, General Hospital of Northern Theater Command, No. 83 Wenhua Road, Shenyang, Liaoning 110840, China