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排序方式: 共有215条查询结果,搜索用时 15 毫秒
61.
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Julene S. Carvalho 《黑龙江环境通报》2004,24(13):1060-1067
The detailed study of the fetal cardiac anatomy in the first trimester of pregnancy by means of ultrasound, transvaginally or transabdominally, is feasible and remains a safe procedure provided thermal and mechanical indices are taken into account. Optimal time for successful imaging of the four chambers and great arteries in early gestation appears to be between 13 to 14 weeks. In experienced hands, first-trimester fetal echocardiography is accurate in detecting major structural cardiac abnormalities and yields a high negative predictive value. Thus, in a clinical setting, it can be offered to families considered to be ‘at risk’ of cardiac defects (e.g. those with previous family history or when fetal nuchal translucency is increased) and can be a powerful tool to reassure families regarding normality of major cardiac structures and connections. However, the early detection of an important structural abnormality (chromosomally normal or not) may be associated with a high termination rate if this is an acceptable option. The high prevalence of associated chromosomal and extracardiac abnormalities for many of the high-risk families, who may benefit from this approach, cannot be ignored. Therefore, fetal heart scanning in the first trimester should be performed in conjunction with detailed first-trimester obstetric scanning. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Min Chen Dr Yung Hang Lam Chen Lung Lin Kwok Wah Chan Pui Wah Hui Mary Hoi Yin Tang Chin Peng Lee Pek Lan Khong 《黑龙江环境通报》2002,22(12):1067-1070
Enteric duplication cyst is a congenital abnormality that is believed to arise from abnormal recanalization of the bowel during embryogenesis. Previous reports suggest that the condition may be suspected prenatally by sonographic demonstration of an intra-abdominal cystic mass in the second and third trimesters. We present the sonographic features of a fetus with ileal duplication cyst at 12 weeks of gestation, which show that the condition may present in the first trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
66.
Initially described in 1972, Bartsocas–Papas syndrome (BPS) is an autosomal recessively inherited disorder combining multiple pterygia, ankyloblepharon, cleft lip and palate, filiform bands between the jaws, syndactyly, and other anomalies. Although described as lethal, review of the literature reveals three individuals who survived into childhood with this condition. We describe a fourth surviving patient and what we believe to be the first prenatal diagnosis of BPS in the first trimester. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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B. Masturzo J. A. Hyett K. D. Kalache G. Rumsby E. Jauniaux C. H. Rodeck 《黑龙江环境通报》2001,21(4):314-316
We present two cases of pregnant women with a previous history of congenital adrenal hyperplasia. In both cases the only abnormal feature in the initial pregnancy had been increased nuchal translucency at 10–14 weeks of gestation. The fetal karyotype was normal and a diagnosis of congenital adrenal hyperplasia was made after delivery. In their current pregnancies, both fetuses also had increased nuchal translucency and normal fetal karyotype. Diagnosis of 21-hydroxylase deficiency was made prenatally by DNA analysis. These findings in four affected fetuses suggest that congenital adrenal hyperplasia should be added to the list of genetic anomalies associated with an increase in nuchal translucency. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
69.
Waldo Sepulveda Cecilia Be Ronald Youlton Eduardo Carstens Marcelo Reyes 《黑龙江环境通报》2001,21(9):726-728
In order to determine the significance of nuchal translucency thickness on the subsequent natural history of first-trimester fetuses with a chromosome translocation, seven consecutive cases diagnosed between 11 and 13 weeks of gestation were reviewed. Nuchal translucency measurements were successfully obtained before chorionic villus sampling (CVS) in all cases. Three fetuses had an unbalanced translocation and all were associated with increased nuchal translucency and multiple anomalies at the detailed second-trimester scan. There were no survivors in this group. The remaining four fetuses had a balanced translocation; all had normal nuchal translucency thickness and no structural anomalies were detected in the second trimester. Three of these fetuses were born at ≥35 weeks of gestation and were phenotypically normal. However, an unexpected single fetal demise occurred in a dichorionic twin pregnancy at 28 weeks of gestation. It is concluded that nuchal translucency measurements provide important prognostic information on pregnancy outcome in first-trimester fetuses with a chromosome translocation. In parents with a known balanced translocation, the detection of increased nuchal translucency at 11–14 weeks of gestation is associated with unbalanced translocations, structural anomalies and poor pregnancy outcome. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
70.
Kevin Spencer Adolfo W. Liao Charas Y. T. Ong Lut Geerts Kypros H. Nicolaides 《黑龙江环境通报》2001,21(6):441-444
Dimeric inhibin A was measured in maternal serum samples from 45 pregnancies affected by trisomy 21 and 493 samples from unaffected pregnancies at 10–14 weeks of gestation. Inhibin A levels in affected pregnancies were compared with levels of free β-hCG and PAPP-A in the same series. In the trisomy 21 group, the median multiple of the median (MoM) inhibin A was not significantly elevated (1.28 vs 1.00) with only 15.5% being above the 95th centile. In contrast, the median MoM free β-hCG was significantly increased (2.05 vs 1.00) with 36% above the 95th centile and PAPP-A was significantly reduced (0.49 vs 1.00) with 42% below the 5th centile. Inhibin A levels in the trisomy 21 group were significantly correlated with gestational age such that median levels rose from 1.04 at 11 weeks to 1.30 at 12 weeks and 1.67 at 13 weeks. These findings suggest that first trimester biochemical screening for trisomy 21, which is currently optimised using maternal serum free β-hCG and PAPP-A and fetal nuchal translucency, will not benefit from the inclusion of inhibin A. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献