1. Center for Laboratory Diagnosis, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong 370600, P.R. China
2. Department of General Surgery, Zhongshan Hospital of Fudan University, Qingpu, Shanghai 201700, P.R. China
3. Department of Gynaecology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong 370600, P.R. China