title: [Analysis of Down syndrome screening by maternal serum detection in mid-pregnancy].
authors.affiliation: Department of Medical Genetics, Tung Wah Hospital, Sun Yat-sen University, Guangzhou, China. liuliang71215@163.com
authors.forename: Yan-hui
authors.initials: YH
authors.lastname: Liu
authors.forename: Li-fen
authors.initials: LF
authors.lastname: Li
authors.forename: Ya-min
authors.initials: YM
authors.lastname: Wu