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Accuracy of fetal echocardiography 总被引:6,自引:0,他引:6
The reliability of prenatal ultrasound (US) for the detection of structural heart defects was investigated in a consecutive population of patients referred for prenatal US. Twenty-eight of 49 fetuses (57%) shown to have one or more heart defects with physical examination or autopsy were found to have congenital heart disease with prenatal US. There were 66 cardiac defects in 49 fetuses, 33 of which were entirely or partly identified (50%). Defects correctly diagnosed included hypoplasia of either ventricle, common atrioventricular canal, tetralogy of Fallot, transposition of the great vessels, and Ebstein anomaly. Defects rarely diagnosed correctly included semilunar valve stenosis, total anomalous pulmonary venous drainage, coarctation of the aorta, pulmonic atresia, atrioseptal defect, and ventricular septal defect. Many types of heart defects can be diagnosed accurately with prenatal US in a general population of patients not at high risk for congenital heart disease. Some lesions, however, were difficult to detect. 相似文献
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Structure and Development of Neuronal Connections in Isogenic Organisms: Cellular Interactions in the Development of the Optic Lamina of Daphnia 总被引:4,自引:2,他引:4 下载免费PDF全文
V. Lopresti E. R. Macagno C. Levinthal 《Proceedings of the National Academy of Sciences of the United States of America》1973,70(2):433-437
Some details of the growth and initial cellular interactions of optic nerve axons were examined in a parthenogenetic clone of Daphnia magna. Results are summarized as follows: (i) the final structure of the optic lamina is dependent upon interactions between growing optic nerve fibers and optic lamina neuroblasts closest to the midplane of the animal, which trigger the morphological differentiation of the neuroblasts; the specificity of connections is achieved by well-defined sequences of cell migration in the ganglion; (ii) only one of the eight optic nerve axons growing back from each ommatidium in the eye possesses a structure similar to the growth cones seen on termini of nerve fibers growing in vitro; and (iii) undifferentiated neuroblasts in the ganglion react to surface contact by this "lead axon" by enveloping the axon in a glial-like relationship. 相似文献
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GHADA BEAINO BABAK KHOSHNOOD MONIQUE KAMINSKI VÉRONIQUE PIERRAT STÉPHANE MARRET JACQUELINE MATIS BERNARD LEDÉSERT GÉRARD THIRIEZ JEANNE FRESSON JEAN‐CHRISTOPHE ROZÉ VÉRONIQUE ZUPAN‐SIMUNEK CATHERINE ARNAUD ANTOINE BURGUET BÉATRICE LARROQUE GÉRARD BRÉART PIERRE‐YVES ANCEL for the EPIPAGE Study Group 《Developmental medicine and child neurology》2010,52(6):e119-e125
Aim The aim of this study was to assess the independent role of cerebral lesions on ultrasound scan, and several other neonatal and obstetric factors, as potential predictors of cerebral palsy (CP) in a large population‐based cohort of very preterm infants. Method As part of EPIPAGE, a population‐based prospective cohort study, perinatal data and outcome at 5 years of age were recorded for 1812 infants born before 33 weeks of gestation in nine regions of France in 1997. Results The study group comprised 942 males (52%) and 870 females with a mean gestational age of 30 weeks (SD 2wks; range 24–32wks) and a mean birthweight of 1367g (SD 393g; range 450–2645g). CP was diagnosed at 5 years of age in 159 infants (prevalence 9%; 95% confidence interval [CI] 7–10%), 97 males and 62 females, with a mean gestational age of 29 weeks (SD 2wks; range 24–32wks) and a mean birthweight of 1305g (SD 386g; range 500–2480g). Among this group, 67% walked without aid, 14% walked with aid, and 19% were unable to walk. Spastic, ataxic, and dyskinetic CP accounted for 89%, 7%, and 4% of cases respectively. The prevalence of CP was 61% among infants with cystic periventricular leukomalacia, 50% in infants with intraparenchymal haemorrhage, 8% in infants with grade I intraventricular haemorrhage, and 4% in infants without a detectable cerebral lesion. After controlling for cerebral lesions and obstetric and neonatal factors, only male sex (odds ratio [OR] 1.52; 95% CI 1.03–2.25) and preterm premature rupture of membranes or preterm labour (OR 1.72; 95% CI 0.95–3.14) were predictors of the development of CP in very preterm infants. Interpretation Cerebral lesions were the most important predictor of CP in very preterm infants. In addition, infant sex and preterm premature rupture of membranes or preterm labour were also independent predictors of CP. 相似文献
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NiX HouY KingBR TangX ReadMA SmithR NicholsonRC 《第二军医大学学报》2005,26(4):385-385
Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780, 相似文献
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