1. National Engineering Research Center for Biomaterials, College of Biomedical Engineering, Sichuan University , Chengdu, Sichuan 610064, China
2. Institute of Regulatory Science for Medical Devices, Sichuan University , Chengdu, Sichuan 610064, China
3. Department of Gastroenterology, Sichuan Province People's Hospital, University of Electronic Science and Technology of China , Chengdu, Sichuan 610072, China