1. Department of Clinical Laboratory, The Second Hospital of Dalian Medical University, Dalian, Liaoning 116023, P.R. China
2. Department of Gynecology and Obstetrics, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
3. College of Laboratory Medicine, Dalian Medical University, Dalian, Liaoning 116044, P.R. China