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Placental malaria. I. Pathological classification 总被引:10,自引:0,他引:10
Pregnant women are more likely to contract malaria than their non-pregnant counterparts. The aim of this study was to develop a simple classification system for the histopathological diagnosis of placental malaria infection applicable to placentas collected in field conditions. The placentas were classified into four groups depending on the presence and disribution of parasites and malaria pigment: active infection, active-chronic infection, past-chronic infection, not infected. The frequency of parasitized placentas (26.4%) was in keeping with the prevalence of placental parasitaemia documented in epidemiological studies. An additional 29.8% placentas showed pigment in fibrin only, indicating pastchronic infection. Chronic placental malaria infection was most common in primigravidae, possibly reflecting ineffective clearance of parasites from the placenta. Seasonal fluctuations between infection categories support progression of placental infection with delayed clearance of pigment from fibrin. The proposed classification system has allowed diagnosis of different categories of placental malaria infection by two independent observers. A stadardized method of diagnosis may enhance understanding of placental pathology and reduced birth weight in malaria infection during pregnancy. 相似文献
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[目的 ]探讨前置胎盘分娩方式的选择及分娩过程中减少出血的方法。 [方法 ]对 2 6例前置胎盘病例的发病率、诊断方法、胎盘分型、分娩方式、出血情况及剖宫产术子宫切口方式与出血的关系几个方面进行回顾性分析。[结果 ]2 6例中手术率为 96 .1 5 % ,阴道分娩率为 3.85 % ,1例阴道分娩出血量为 6 0 0mL ,剖宫产术平均出血量为 6 74 .5 5mL ;剖宫产术中切口方式选择推开胎盘与避开胎盘出血量比较 ,差异无显著性 (P >0 .0 5 ) ,切开胎盘与推开胎盘出血量比较及切开胎盘与避开胎盘的出血量比较 ,差异均有显著性 (P均 <0 .0 1 )。[结论 ]剖宫产术可成为前置胎盘终止妊娠的主要方法 ,同时原则上应避开胎盘选择切口 相似文献
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目的 制备人胎盘基因表达谱芯片,前用于基因差异表达分析。方法用基因芯片点样仪将胎盘基因文库探针打印在氨基包被的玻片上制备表达谱芯片。分别提取对照组三氧化二砷处理的K562细胞总RNA,纯化mRNA后反转录成cDNA。再以限制性显示技术进行荧光标记,将两组荧光标记的样品混合后与芯片进行杂交。杂交后清洗芯片,干燥后对芯片进行扫描,分析杂交结果。结果 建立了较可靠的制备与检测基基表达芯片的方法,并筛选出45个差异表达基因片段。结论 制备的人胎盘基因表达谱芯片可有效地应用于基因的差异表达分析。 相似文献
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Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·109 l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects. 相似文献
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Summary We have identified cells which secrete human chorionic gonadotropin (HCG) of cultures if first trimester placental villi. As a first step, we identified epithelial cells using a new monoclonal antibody. We then added HCG antibodies to the cultured cells. We found that syncytiotrophoblast (and not cytotrophoblast), Hofbauer cells and some mesenchymal cells stained with HCG antibodies. 相似文献
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Caesarean scar pregnancy 总被引:10,自引:1,他引:9
Ash A Smith A Maxwell D 《BJOG : an international journal of obstetrics and gynaecology》2007,114(3):253-263
Caesarean scar pregnancy is one of the rarest forms of ectopic pregnancy. Little is known about its incidence and natural history. With increasing incidence of caesarean section worldwide, more and more cases are diagnosed and reported. Transvaginal ultrasound and colour flow Doppler provides a high diagnostic accuracy with very few false positives. A delay in diagnosis and/or treatment can lead to uterine rupture, major haemorrhage, hysterectomy and serious maternal morbidity. Early diagnosis can offer treatment options of avoiding uterine rupture and haemorrhage, thus preserving the uterus and future fertility. Management plan should be individually tailored. Available data suggest that termination of pregnancy is the treatment of choice in the first trimester soon after the diagnosis. Expectant treatment has a poor prognosis because of risk of rupture. There are no reliable scientific data on the risk of recurrence of the condition in future pregnancy, role of the interval between the previous caesarean delivery and occurrence of caesarean scar pregnancy, and effect of caesarean wound closure technique on caesarean scar pregnancy. In this article, we aim to find the demography, pathophysiology, clinical presentation, most appropriate methods of diagnosis and management, with their implications in clinical practice for this condition. 相似文献
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Kevin Brooks Hanem Hasan Sridhar Samineni Venu Gangur Wilfried Karmaus 《Pediatric allergy and immunology》2007,18(7):621-624
Placental p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) concentration and cord blood atopic markers were determined in 19 neonates. Increased placental p,p'-DDE was associated with a statistically significant increase in cord plasma interleukin (IL)-13. Furthermore, both cord plasma IL-4/interferon (IFN)-gamma and IL-13/IFN-gamma ratios were significantly positively associated with placental p,p'-DDE concentration. 相似文献
10.
抗乙肝胎盘转移因子的特异免疫活性观察 总被引:8,自引:0,他引:8
本研究由HBVM-Ab阳性胎盘提取的抗乙肝胎盘转移因子(PSTF)的特异免疫活性证明,经注射,小鼠外周血淋巴细胞明显增多,胸腺重量和指数亦显著增加,酯酶染色证明75%属T-样淋巴细胞,25%属Thy-样淋巴细胞,人白细胞或小鼠白细胞体外转移PSTF特异免疫活性、或豚鼠和小鼠体内转移PSTF特异免疫活性,再取其白细胞作白细胞粘附抑制、白细胞移动抑制、特异淋巴细胞转化、小鼠足掌注射和诱生γ-干扰素试验 相似文献