1. Department of Gastroenterology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, Fujian 362000, P.R. China
2. Department of Thoracic Surgery, Fujian Medical University Union Hospital, Fuzhou, Fujian 350005, P.R. China
3. Department of Orthopaedics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong 510630, P.R. China
4. Department of Medical Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan 450008, P.R. China