1. Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
2. Science and Experiment Center, China Medical University, Shenyang, Liaoning 110122, P.R. China
3. Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China