trisomy 21

Compared to the control group, the detection rate of trisomy 21 in genetic ultrasound group was significantly higher than routine ultrasound ( 86.67% vs 30.77%, P < 0.05);

对21三体胎儿超声异常征象检出率亦显著高于普通超声检查组（86.67%比30.77%，P<0.05）。

The detection rate of fetal chromosomal abnormalities was 80.77%, the detection rate of fetuses with trisomy 21 was 87.50% for a false-positive rate of 6.50%.

染色体异常检出率为80.77%，假阳性率为6.50%；21三体检出率为87.50%。

Examination of the nasal bone can increase the detection rate of screening of fetuses with trisomy 21 by the first trimester scan and serum biochemistry over 95%.

鼻骨检查结合母血生化测定综合筛查可使21-三体综合征的检出率上升到95%以上。

Nasal bone in first-trimester screening for trisomy 21

妊娠早期鼻骨测量用于21-三体筛查

Observation on the Rate of Satellite Association in Young Couples with Trisomy 21 Offsprings

21-三体患儿的年轻双亲染色体随体联合率的研究

The detection rate of the chromosomal abnormality of the abnormal fetus detected by ultrasound ( 33.33%) was higer than the trisomy 21 high risk group ( 4.54%) and abnormal delivery group ( 9.09%)( P < 0.05).

其中超声示胎儿异常组染色体异常检出率（33.33%）明显高于21-三体高风险组（4.54%）、不良孕产史组的检出率（9.09%）（P<0.05）。

Objective To explore the diagnosis, prenatal diagnosis and early intervention of trisomy 21 syndrome ( Down syndrome, DS) at cellular, cell-molecular and molecular levels.

目的在细胞、细胞分子和分子水平对21三体综合征（Down syndrome，DS）进行诊断和干预。

Ultrasound screening for trisomy 21 syndrome at 11-13~ (+ 6) gestational weeks

超声在孕11-13~（+6）周筛查21-三体综合征中的作用

Meta-analysis of prenatal screening for trisomy 21 using nuchal translucency measurement with serum markers

血清学指标结合颈部透明膜产前筛查21-三体综合征的Meta分析

ONE CASE OF 'RING-TYPE' TRISOMY 21 SYNDROME: identified by high-resolution G-banding technique

用高分辨G带技术鉴定一例环形21三体综合征

Inter-FISH showed that the nucleus with five hybride signals was 38.5%. This result was full agreement with trisomy 21 determined by cytogenetics.

羊水细胞间期FISH结果显示，含5个杂交信号的核占所有杂交核的385%，与细胞遗传学分析的21三体核型完全一致。

Application of inter fluorecence in situ hybridization of chromosome 13/ 21 α satellite probe in amniotic cells for prenatal diagnosis trisomy 21 syndrome

染色体13/21α卫星探针用于产前诊断21三体综合征

Results The detection rate of trisomy 21 and trisomy 18 by maternal serum markers was 0.053% ( 7/ 13175); false positive rate was 10.69%.

结果21-三体综合征及18-三体综合征的检出率为5.3/万，假阳性率为10.69%。

Advances in study on relationship between maternal deficiency of folic acid and fetal trisomy 21 syndrome

母体叶酸缺乏与胎儿21-三体综合征关系的研究

Conclusion The detection rate of trisomy 21 fetuses can be improved by mid trimester ultrasound finding of the increased nuchal fold thickness, especially in those cases with a maternal age less than 35 years and no major fetal abnormalities.

结论应用颈背部皮肤增厚这一超声指标可以提高产前21三体胎儿检出率，特别是母亲年龄小于35岁，且不合并严重畸形的病例，减少产前漏诊。

[ Results] Eighteen cases with typical trisomies were detected by STR-PCR, among them, there were sixteen trisomy 21, one trisomy 18 and one trisomy 13 respectively, in which 4 were fetuses from prenatal diagnosis.

【结果】检出18例完全型染色体三体综合征，包括21三体16例；18三体和13三体各1例，其中4例为产前诊断的胎儿。

Detection of Trisomy 21 Fetuses by Mid-Trimester Ultrasound

21-三体胎儿的孕中期超声检出

Therefore, maternal deficiency of folic acid in pregnancy can finally cause development of fetal trisomy 21 syndrome by its effect on the methylation of DNA in oocyte during secondary meiotic division.

故妊娠期母体叶酸缺乏可能通过影响DNA甲基化最终导致胎儿21-三体综合征的发生。

A Method for Rapid and Early Diagnosis of Trisomy 21 Using Molecular Techniques

DNA分析法快速诊断21三体综合征

Study of Ag-stained NORS in Trisomy 21 Families

21三体征家庭的银染核仁形成区的研究