1. Department of Thyroid and Breast Surgery, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China
2. Department of Pathology, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China
3. Department of Hospital Office, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China