[1] Qingdao Univ, Eye Coll, State Key Lab Cultivat Base, Shandong Prov Key Lab Ophthalmol,Shandong Eye Ins, Qingdao 266071, Peoples R China
[2] Natl Res Inst Family Planning, Beijing 100084, Peoples R China
[3] Tsinghua Univ, State Key Lab Biomembrane & Membrane Biotechnol, Sch Life Sci, Beijing 100084, Peoples R China
[4] Lanzhou Univ, Inst Biophys, Lanzhou 730000, Peoples R China
[5] Peking Union Med Coll, Grad Sch, Beijing 100021, Peoples R China
[6] World Hlth Org Collaborating Ctr Res Human Reprod, Beijing, Peoples R China