[1] Shandong Univ, QiLu Hosp, Dept Clin Lab, Jinan 250100, Peoples R China
[2] Mercer Univ, Sch Med, Dept Biomed Sci, Savannah, GA 31404 USA
[3] Mayo Clin, Dept Obstet & Gynecol, Rochester, MN 55905 USA
[4] Mayo Med Coll, Rochester, MN 55905 USA
[5] Jinan Nursing Coll, Dept Immunol, Jinan, Peoples R China
[6] Shantou Univ, Med Coll Shantou, Shantou, Guangdong, Peoples R China
[7] Mem Univ Med Ctr, Dept Obstet & Gynecol, Savannah, GA 31404 USA