Department of Clinical Laboratory Medicine, the Second People's Hospital of Xining City Qinghai Province, Xining City, Qinghai Province, 810003;
Department of Obstetrics, the Second People's Hospital of Xining City Qinghai Province, Xining City, Qinghai Province, 810003;
Department of Clinical Laboratory Medicine, the Fourth People's Hospital of Qinghai Province, Xining City, Qinghai Province, 810003;