1. Department of Pathology, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P. R. China
2. Department of Gynaecology and Obstetrics, Jinan Central Hospital, Shandong University, Jinan, Shandong 250012, P. R. China
3. Medical School of Shandong University, Jinan, Shandong 250012, P. R. China
4. Department of Orthopaedics, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P. R. China
5. Department of Oral and Maxillofacial Surgery and Institute of Dental Medicine, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P. R. China