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81.
目的探讨高危孕妇胎盘植入的临床危险因素及MRI价值征象。方法91例高危孕妇,年龄23~44岁、平均年龄32岁;孕周27~38.5周、平均孕周36.2周;分别分析临床资料及MRI宫内征象1)胎盘异常增厚及胎盘内T2WI低信号带;2)胎盘与肌层分界线不连续或中断;3)子宫肌层变薄及局部膨隆。最终诊断结果均经手术及病理证实。采用卡方检验比较临床高危因素及MRI宫内征象在总体胎盘植入与对照组间以及MRI宫内征象在胎盘植入组内的统计学差异。结果41/91例为胎盘植入,其中26例浅植入(胎盘粘连)、13例胎盘深植入、2例胎盘穿透,余50例阴性。临床资料剖宫产和/或流产史次数大于等于2次、前置胎盘以及上述MRI宫内征象在总体胎盘植入组间均具有统计学差异(P<0.05)。其中胎盘T2WI低信号带(P=0.015)、胎盘与肌层分界线不连续或中断(P=0.007)、子宫肌层变薄(P=0.000)及局部膨隆(P=0.006)在胎盘植入组内具有统计学差异。结论剖宫产和/或流产史次数大于等于2次及前置胎盘是高危孕妇胎盘植入的临床危险因素。上述MRI宫内征象均为高危孕妇胎盘植入的价值征象。其中胎盘与肌层分界线不连续或中断,是胎盘浅植入的敏感征象。除胎盘异常增厚外,余下MRI宫内价值征象出现越多,提示胎盘植入越深,危险性越大。 相似文献
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Human endogenous retroviruses (ERVs) represent 8% of the total human genome. Although the majority of these ancient proviral sequences have only retained non-coding long terminal repeats (LTRs), a number of “endogenized” retroviral genes encode functional proteins. Previous studies have underlined the implication of these ERV-derived proteins in the development and the function of the placenta. In this review, we summarize recent findings showing that two ERV genes, termed Syncytin-1 and Syncytin-2, which encode former envelope (Env) proteins, trigger fusion events between villous cytotrophoblasts and the peripheral multinucleated syncytiotrophoblast layer. Such fusion events maintain the stability of this latter cell structure, which plays an important role in fetal development by the active secretion of various soluble factors, gas exchange and regulation of fetomaternal immunotolerance. We also highlight new studies showing that these ERV proteins, in addition to their localization at the cell surface of cytotrophoblasts, are also incorporated on the surface of various extracellular microvesicles, including exosomes. Such exosome-associated proteins could be involved in the various functions attributed to these vesicles and could provide a form of tropism. Additionally, through their immunosuppressive domains, these ERV proteins could also contribute to fetomaternal immunotolerance in a local and more distal manner. These various aspects of the implication of Syncytin-1 and -2 in placental function are also addressed in the context of the placenta-related disorder, preeclampsia. 相似文献
84.
梁振停 《中国继续医学教育》2015,(19)
目的探讨经腹彩色多普勒超声在前置胎盘并发胎盘植入诊断中的临床价值。方法选取2012年4月~2015年4月在我院接受治疗的前置胎盘合并胎盘植入患者共100例,采用经腹彩色多普勒对所有患者进行检查,分析检查结果。结果经腹彩色多普勒超声诊断后,共诊断为前置胎盘并发胎盘植入的患者共52例,准确率为98.1%,漏诊患者1例,漏诊率为1.9%。结论采用经腹彩色多普勒超声对产妇的前置胎盘并发胎盘植入疾病进行诊断具有良好的临床价值。 相似文献
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86.
Herbert Juch Liudmila Nikitina Sabine Reimann Martin Gauster Gottfried Dohr Barbara Obermayer-Pietsch 《Nanotoxicology》2018,12(2):90-103
A thorough understanding of nanoparticle bio-distribution at the feto-maternal interface will be a prerequisite for their diagnostic or therapeutic application in women of childbearing age and for teratologic risk assessment. Therefore, the tissue interaction of biocompatible dendritic polyglycerol nanoparticles (dPG-NPs) with first- trimester human placental explants were analyzed and compared to less sophisticated trophoblast-cell based models. First-trimester human placental explants, BeWo cells and primary trophoblast cells from human term placenta were exposed to fluorescence labeled, ~5?nm dPG-NPs, with differently charged surfaces, at concentrations of 1 µM and 10?nM, for 6 and 24?h. Accumulation of dPGs was visualized by fluorescence microscopy. To assess the impact of dPG-NP on trophoblast integrity and endocrine function, LDH, and hCG releases were measured. A dose- and charge-dependent accumulation of dPG-NPs was observed at the early placental barrier and in cell lines, with positive dPG-NP-surface causing deposits even in the mesenchymal core of the placental villi. No signs of plasma membrane damage could be detected. After 24?h we observed a significant reduction of hCG secretion in placental explants, without significant changes in trophoblast apoptosis, at low concentrations of charged dPG-NPs. In conclusion, dPG-NP’s surface charge substantially influences their bio-distribution at the feto-maternal interface, with positive charge facilitating trans-trophoblast passage, and in contrast to more artificial models, the first-trimester placental explant culture model reveals potentially hazardous influences of charged dPG-NPs on early placental physiology. 相似文献
87.
88.
《Hypertension in pregnancy》2013,32(4):457-472
Studies in mice have shown that a variety of genes, including GCM1, regulate the differentiation of trophoblast cells. GCM1 is also expressed in the human placenta. Placental GCM1 protein has been reported to be reduced in preeclampsia. In view of the close link between hypoxia, hypoxia-reoxygenation, preeclampsia, placental development and the reported reduction in GCM1, we hypothesised that GCM1 expression would be affected by hypoxia. The aim was to determine the effects of hypoxia on GCM1 expression in the human placenta. Two model systems were used; villous explants and cultured primary cytotrophoblast cells. GCM1 protein was detectable at low levels in explants maintained for 7 h in 8 or 20% O2. A striking increase in GCM1 was observed when villous explants were incubated for 1h in 1% O2 (p < 0.002). Incubation of explants for 1 h in 1% O2 followed by re-oxygenation for 6 h in 8 or 20% O2 resulted in a decline in GCM1 protein. Expression of GCM1 was also analysed in primary cytotrophoblast and syncytiotrophoblast cultured in 8 or 20% O2 or reduced oxygen (1–2% O2) conditions. GCM1 protein was not detected in any of the experimental conditions used. This study has shown that acute hypoxia increases GCM-1 protein in villous explants. The experiments with purified trophoblast do not support a role for hypoxia increasing GCM-1 in these cells under the conditions used. The present findings are in keeping with the complex effects of oxygen depending on the conditions used. The hypoxic effects on GCM1 warrant further investigation as they may provide further information on the pathogenesis of preeclampsia. 相似文献
89.
90.
目的:总结和分析临床上在前置胎盘孕妇护理过程中应该注意的事项,为今后前置胎盘孕妇的合理护理提供参考。方法:将我院于近期在临床上收集到140例前置胎盘孕妇的护理情况进行回顾性统计分析,总结护理过程中应注意的事项。结果:在我们在收集的所有病例中,前置胎盘孕妇护理的主要环节包括:心理护理,产前护理和产后护理等。结论:只有不断提高医护人员的护理水平,采取正确的护理手段,才能有效延长孕周,提高新生儿的成活率,减少并发症的发生。 相似文献