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71.
Yaqing Zhou Yan Quan Yijun Wu Yinxing Zhang 《The Journal of international medical research》2022,50(9)
The 18q12.3 region contains the SET binding protein 1 (SETBP1) gene. SETBP1 mutations or deletions are associated with Schinzel–Giedion syndrome or intellectual developmental disorder, autosomal dominant 29. We report the prenatal diagnosis and genetic counseling of a patient with a maternally inherited 18q12.3 microdeletion. In this family, the mother and son carried the same microdeletion. Chromosomal microdeletions and microduplications are difficult to detect using conventional cytogenetics, whereas the combination of prenatal ultrasound, karyotype analysis, chromosomal microarray analysis, and genetic counseling is helpful for the prenatal diagnosis of chromosomal microdeletions/microduplications. 相似文献
72.
胎儿大脑中动脉(MCA)是胎儿大脑血流供应最丰富的血管,对反映胎儿脑部血液循环改变及血氧情况的变化有重要的临床应用价值。正常妊娠时,随着孕周增加,胎儿脑部发育逐渐完善,胎儿MCA彩色多普勒超声血流信号指标的变化呈抛物线模式。在高危妊娠中,胎盘功能不足、血管阻力增加与不良妊娠结局之间呈一定的相关性。MCA具有自身调节功能,当胎儿的内外环境出现变化时如缺氧等可导致MCA的血流动力学发生改变,而胎儿MCA彩色多普勒超声的各项血流信号指标也呈异常的变化趋势。彩色多普勒超声检查胎儿MCA血流动力学指标对母儿双方安全、无创、方便以及可重复性高,可用来反映胎儿的一系列病理生理改变,成为近年来临床评估胎儿生长发育和宫内安危状况的重要监测手段。。 相似文献
73.
46例Turner综合征患者临床特征及染色体分析 总被引:3,自引:0,他引:3
目的Turner综合征患者身材矮小伴不同程度的性腺发育不全,探讨Turner综合征不同核型的遗传学特征、临床特点及其所占比例。方法高龄或高危孕妇产前诊断及成人外周血染色体核型分析。结果产前诊断发现Turner综合征9例,成人外周血检测发现Turner综合征37例,46例患者中45,X25例(54.35%);45,X/46,XX嵌合型4例(8.70%);45,X/46,X,i(X)嵌合型3例(6.52%);46,X,i(X)2例(4.35%);46,XX,inv(X)2例(4.35%);46,XY7例(15.22%);45,X/46,XX/47,XXX嵌合型,46,XX,t(X;3)和45,X/46,XX,del(X)各1例,分别占2.17%。结论Turner综合征包括X染色体数目异常和结构畸变等多种核型,均可不同程度导致女性不孕、智力低下及其他器官功能异常,应提倡优生优育,做好产前诊断。 相似文献
74.
Fetal blood sampling during pregnancy with use of a needle guided by ultrasound: a study of 606 consecutive cases 总被引:15,自引:0,他引:15
F Daffos M Capella-Pavlovsky F Forestier 《American journal of obstetrics and gynecology》1985,153(6):655-660
Because of various prenatal diagnoses, 606 fetal blood samplings were carried out in 562 pregnancies from the gestational week 17 to 38 with use of a 20-gauge needle guided by ultrasound. The procedure was performed on outpatients under local anesthesia and without medication before or after the procedure. Pure fetal blood was obtained at the first attempt in 588 cases. A second attempt was necessary in 18 cases. Maternal blood contamination was never present. Amniotic fluid dilution was noted in 15 cases. At the beginning of our experience only three cords could not be punctured. The duration of the procedure was less than 10 minutes in 90% of cases. Fifty-eight pregnancies were terminated after consideration of the results of the diagnosis, and 504 pregnancies were continued. The complications found in these pregnancies were premature delivery (5%), growth retardation (8%), in utero death (1.1%), and spontaneous abortion (0.8%). In the future this new procedure could replace fetoscopy and initiate an important field of new investigations. 相似文献
75.
超声测量胎儿腹围预测新生儿出生体重的研究 总被引:15,自引:0,他引:15
目的探讨超声测量胎儿腹围在预测新生儿出生体重和诊断巨大儿中的价值。方法在孕妇分娩前1周超声测量胎儿腹围,追踪胎儿的出生体重,分析胎儿腹围与出生体重的关系。结果(1)共检测1475例单胎孕妇胎儿,胎儿腹围与出生体重呈直线正相关关系,r为0.85(P<0.01)。(2)胎儿腹围<34cm者中无一例巨大儿;胎儿腹围<35cm有1007例,99.7%的新生儿平均出生体重<4000g;胎儿腹围在35~35.9cm有206例,新生儿平均出生体重为(3691±277)g,其中14.6%(30例)的新生儿出生体重≥4000g;胎儿腹围在36~36.9cm有149例,其中51.0%(76例)的新生儿出生体重≥4000g,新生儿平均出生体重为(3957±256)g;胎儿腹围在37~37.9cm有64例,其中84.4%(54例)的新生儿出生体重≥4000g,平均出生体重(4205±250)g;胎儿腹围≥38cm有44例,新生儿平均出生体重≥4000g者为100%(44例),平均出生体重为(4489±267)g。(3)1475例中有811例孕妇行剖宫产术(55.0%),新生儿出生体重为4000~4500g者,剖宫产率为71.4%(125/175),出生体重≥4500g者,剖宫产率为93.8%(30/32),均显著高于新生儿出生体重<4000g的剖宫产率(P<0.01)。结论超声测量胎儿腹围可以预测新生儿出生体重。胎儿腹围与胎儿体重呈高度直线正相关。胎儿腹围<35cm提示发生巨大儿的可能性极低;≥37cm提示巨大儿的可能性大。 相似文献
76.
Chih-Ping Chen Ming Chen Shun-Ping Chang Fang-Yu Hung Meng-Ju Lee Schu-Rern Chern Peih-Shan Wu Yen-Ni Chen Shin-Wen Chen Chen-Chi Lee Dai-Dyi Town Wen-Lin Chen Wayseen Wang 《Taiwanese journal of obstetrics & gynecology》2017,56(2):234-237
Objective
We present prenatal diagnosis and molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome (sSMC) derived from chromosome 2.Case Report
A 42-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XY,+mar[10]/46,XY[12]. The parental karyotypes were normal. Array comparative genomic hybridization analysis of the DNA extracted from cultured amniocytes revealed no genomic imbalance. Spectral karyotyping analysis failed to identify the sSMC. Metaphase fluorescence in situ hybridization analysis using the satellite probes CEP1/5/19, CEP2, CEP3, CEP4, CEP6, CEP7, CEP8, CEP9, CEP10, CEP12, CEP13/21, CEP14/22, CEP15, CEP16, and CEP20 revealed a result of 47,XY,+mar .ish der(2)(D2Z+)[10]. The sSMC was derived from the α satellite of chromosome 2. Polymorphic DNA marker analysis using the markers specific for chromosome 2 on the DNAs extracted from cultured amniocytes and parental bloods excluded uniparental disomy 2. At 39 weeks of gestation, a healthy 3394-g male baby was delivered with no phenotypic abnormality. The cord blood had a karyotype of 47,XY,+mar[21]/46,XY[19].Conclusion
Array comparative genomic hybridization and spectral karyotyping may fail to detect an sSMC derived from α satellite, which needs satellite probes for confirmation. 相似文献77.
Heather Murphy CNM MSN Julia C. Phillippi CNM PhD 《Journal of Midwifery & Women's Health》2015,60(1):83-88
Ultrasound is widely used as a screening tool for fetal anomalies. An intracardiac echogenic focus (ICEF) is associated with fetal aneuploidy, particularly trisomy 21, when found with other minor abnormalities known as soft markers. However, when found in isolation, intracardiac echogenic foci are morphologic variations with little or no pathologic significance for the fetus. Ambiguity about the significance of ICEF and other soft markers and the lack of preparation prior to ultrasound can result in unnecessary worry for women and their partners. A variety of tools exist that providers can use to help pregnant women and their partners make informed decisions about ultrasound and fetal screening. 相似文献
78.
Steroid 21-hydroxylase deficiency (21-OHD) accounts for 90–95% of congenital
adrenal hyperplasia (CAH) cases. It is classified into three distinct clinical phenotypes:
the salt-wasting (SW), simple virilizing (SV) and nonclassical forms (NC). As girls with
the SW and SV forms of 21-OHD are exposed to high systemic levels of adrenal androgens
during fetal life, they show genital ambiguity. To ameliorate the degree of genital
virilization, prenatal dexamethasone treatment has been performed for more than two
decades, although mainly in the USA and Europe. This treatment has proven to be effective
in preventing or reducing genital virilization. Some data also show that prenatal
diagnosis and treatment are safe for the mother and fetus. However, prenatal treatment is
still controversial for the following reasons. First, the risk of having an affected
female fetus is only one in eight when both parents are known carriers of the autosomal
recessive trait. Therefore, seven of eight fetuses will receive dexamethasone
unnecessarily, and this raises ethical questions. Furthermore, maternal side effects such
as excessive weight gain and hypertension have been observed. Finally, the long-term
safety and outcome for dexamethasone-exposed children have not been established. In Japan,
prenatal diagnosis and treatment has rarely been reported because of these reasons.
Therefore, we must be cautious, and this treatment should be carried out in special
centers with the approval of their ethical committees, that are capable of performing
chorionic villus sampling (CVS) and subsequently determining the karyotype and genotype of
21-OHD. 相似文献
79.
Lin Liu Zhi-An Li Cun-Ying Cui Lian-zhong Zhang Tao Li 《The journal of maternal-fetal & neonatal medicine》2016,29(3):493-503
Objective: To provide a basis for evaluating the prognosis of small left heart system development in fetuses, we analyzed its related factors.Methods: The fetal echocardiogram was performed in 3859 pregnant women, and then small left heart system development was identified in 69 fetuses. The data of prenatal and postnatal echocardiograms, postnatal cardiac surgical treatment, chromosome and autopsy after induced labor were analyzed in the 69 fetuses.Results: Except 1320 cases losing follow-up, 2539 cases had complete data. Among the 2539 cases, small left heart system development was identified in 69 fetuses. Of the 69 fetuses, 12 had hypoplastic left heart syndrome, 20 premature closure of foramen ovale, 13 total anomalous pulmonary venous drainage, 2 common pulmonary vein lumen atresia, 21 aortic coarctation or interruption and 1 right pulmonary hypoplasia. Among the 69 fetuses, chromosome abnormality was found in 7.Conclusion: There are many etiological factors causing small left heart system development. The prognosis is poor in the fetuses with hypoplastic left heart syndrome, common pulmonary vein lumen atresia, pulmonary hypoplasia, other malformations or/and chromosome abnormality. Fetal echocardiography combined with chromosome examination can provide important bases for making diagnosis and evaluating the prognosis regarding small left heart system development. 相似文献
80.