Retrospective analysis on chromosome karyotypes among 2 018 fetuses in the 2nd trimester pregnancy
DU Manxing, WANG Weijia, SU Nianhua, LU Jianqiang
Laboratory Medicine . 2016, (9): 778 -781 .  DOI: 10.3969/j.issn.1673-8640.2016.09.010