1. Department of Thoracic Surgery, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
2. Department of Outpatients, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
3. Department of Gastroenterology, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China