1. Health Management Center, The Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan 646000, P.R. China
2. Department of Cardiology, Ordos Central Hospital, Baotou Medical College, Ordos, Inner Mongolia Autonomous Region 017000, P.R. China
3. Department of Gastrointestinal Surgery, The Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan 646000, P.R. China
4. Department of Gastroenterology, The Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan 646000, P.R. China