1Spencer K,Liao AW,Ong CY,et al.Maternal serum levels of dimeric inhibin A in pregnancies affected by trisomy 21 in the first trimester.Prenat Diagn,2001,21(6):441-444
2Spencer K,Liao AW,Ong CY,et al.Maternal serum activin A and inhibin A in trisomy 18 pregnancies at 10-14 weeks.Prenat Diagn,2001,21(7):571-574
3Parano E,Falcidia E,Grillo A,et al.Noninvasive prenatal diagnosis of chromosomal aneuploidies by isolation and analysis of fetal cells from maternal blood.Am J Med Genet,2001,101(3):262-267
4Locatelli A,Piccoli MG,Vergani P,et al.Critical appraisal of the use of nuchal fold thickness measurements for the prediction of Down syndrome.Am J Obstet Gynecol,2000,182:192-197
5Tsai MS,Huang YY,Hwa KY,et al Combined measurement of fetal nuchal translucency,maternal serum free beta-hCG,and pregnancy-associated plasma protein A for first-trimester Down's syndrome screening.J Formos Med Assoc,2001,100(5):319-325
6Malone FD,Berkowitz RL,Canick JA,et al.First-trimester screening for aneuploidy:research or standard of care? Am J Obstet Gynecol,2000,182:490-496
7Benn P.Advances in prenatal screening for Down syndrome:Ⅱ first trimester testing,integrated testing,and future directions.Clin Chim Acta,2002,324(1-2):1
9Vergani P,Locatelli A,Piccoli MG,et al.Critical reappraisal of the utility of sonographic fetal femur length in the prediction of trisomy 21.Prenat Diagn,2000,20:210-214
10Filly RA.Obstetrical sonography:the best way to terrify a pregnant woman.J Ultrasound Med,2000,19:1-5
8Dimitrova V, Chernev T, Mazneukova V, et al. Second trimester sonographic screening for Down' s syndrome and other chromosomal abnormalities [ J ]. Akush Ginekol ( Sofiia), 2002, 41 (5) :7:19.
9Yan YL, Yang XX, Sheng L, et al. Uhrasonography in Obstetrics [ M ]. BeiJing : People' s Medical Publishing House, 2002:445.
10Vintzileos AM, Campbell WA, Guzman ER, et alSecond- trimester ultrasound markers for detection of trisomy 21: which markers arebest[ J]. Obstet Gynecol, 1997,89(6) :941-944.