1. Department of Gynecology Ultrasound; The Fourth Hospital of Hebei Medical University; Shijiazhuang China
2. Department of Gastroenterology and Hepatology; The Fourth Hospital of Hebei Medical University; Shijiazhuang China
3. Animal Center; The Fourth Hospital of Hebei Medical University; Shijiazhuang China
4. Department of Surgery; The Fourth Hospital of Hebei Medical University; Shijiazhuang China