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结构蛋白及血管形成因子在体表海绵状静脉畸形中的表达及意义 总被引:3,自引:0,他引:3
目的:研究结构蛋白及血管形成因子(VEGF)在体表海绵状静脉畸形(cavernous venous malformation,CVM)中的表达及意义。方法:1996-2000年CVM病理样本25例,取正常中、小型静脉各12例。采用Envision法免疫组化染色观察Ⅳ型胶原、纤维连接蛋白(Fn)、层粘连蛋白(Ln)及VEGF、血管生成素-1(Ang-1)等血管形成因子的表达,半定量分析结果。结果:Ⅳ型胶原、Fn和Ln在海绵状静脉畸形与中、小静脉中的分类似,但表达量明显较少。畸形组织和小静脉VEGF表达明显强于中型静脉,小静脉Ang-1表达明显强于静脉畸形和中型静脉。结论:Ln及VEGF表达变化可能是海绵状静脉畸形形成发展的重要因素。Ang-1表达减少可能参与海绵状静脉畸形的血管塑形障碍的发生。 相似文献
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Nancy Monroy Marisol López Alicia Cervantes Diana García-Cruz Gildardo Zafra Sonia Canún Juan Carlos Zenteno Susana Kofman-Alfaro 《American journal of medical genetics》2002,107(3):181-189
Turner syndrome is a chromosomal disorder in which all or part of one X chromosome is missing. The meiotic or mitotic origin of most cases remains unknown due to the difficulty in detecting hidden mosaicism and to the lack of meiotic segregation studies. We analyzed 15 Turner patients, 10 with a 45,X whereas the rest had a second cell line with abnormal X-chromosomes: a pseudodicentric, an isochromosome, one large and one small ring, and the last with a long arm deletion. Our aims were: to detect X cryptic mosaicism in patients with a 45,X constitution; to determine the parental origin of the abnormality; to infer the zygotic origin of the karyotype and to suggest the timing and mechanism of the error(s) leading to the formation of abnormal X chromosomes from maternal origin. Molecular investigation did not revealed heterozygosity for any microsatellite, excluding X mosaicism in the 45,X cases. Parental origin of the single X chromosome was maternal in 90% of these patients. Three of the structurally abnormal Xs were maternally derived whereas the other two were paternal. These results allowed us to corroborate breakpoints in these abnormal X chromosomes and suggest that the pseudodicentric chromosome originated from post-zygotic sister chromatid exchange, whereas the Xq deleted chromosome probably arose after a recombination event during maternal meiosis. 相似文献
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Kahraman S Akarsu C Cengiz G Dirican K Sözen E Can B Güven C Vanderzwalmen P 《Human reproduction (Oxford, England)》1999,14(3):726-730
In this study the fertility and outcome of intracytoplasmic sperm injection (ICSI) using megalohead spermatozoa from the ejaculates and testicles was evaluated. Seventeen males with megalohead and pinhead sperm forms in their ejaculate were studied in 22 cycles. A high number of sperm heads without tails and abundant round spermatid forms were commonly observed. Round-headed spermatozoa were seldom accompanied by these severely abnormal spermatozoa. The majority of megalohead spermatozoa were observed to have multiple tails, were predominant in the sample, and were used for ICSI. Ejaculated megalohead spermatozoa were used for ICSI in 15 cycles, while testicular spermatozoa were used in seven cycles where there were no vital spermatozoa or spermatozoa of low vitality in the ejaculate. The same abnormal morphology was observed in the testicles as in the ejaculated spermatozoa in the same males. Mean (+/- SD) low motility 4.7 +/- 5.6% and sperm count (3.8 +/- 4.19 x 10(6)) were common findings in these severely teratozoospermic patients. A low fertilization rate (43.2%) was achieved by using megalohead sperm forms (group I, n = 17) in comparison with the control group (60.2%) which had zero normal sperm morphology according to strict criteria (group II, n = 30) (P <0.01). Furthermore, a low pregnancy rate (9.1%) was obtained in the megalohead sperm group in comparison with the control group (40%) (P <0.05). Low fertilization and pregnancy rates may be due to a high incidence of chromosomal abnormalities from severely defective spermatozoa in the ejaculate. Couples should be counselled and warned about possible low fertilization and pregnancy rates with ICSI when only pinhead and megalohead forms with a high number of sperm heads without tails are present in the ejaculate. 相似文献
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目的:观察加味四逆散对慢性束缚应激大鼠海马部分氨基酸含量的影响。 方法: 大鼠随机分为3组:正常对照组、模型组、加味四逆散组。采用OPA高效液相色谱分析法检测海马氨基酸含量。 结果: 模型组海马谷氨酸(Glu)、天冬氨酸(Asp)含量明显高于正常对照组(P<0.01),γ-氨基丁酸(GABA)和牛磺氨酸(Tau)含量明显低于正常对照组(P<0.01或P<0.05);加味四逆散组Glu、Asp明显低于模型组(P<0.05),GABA和Tau含量变化不明显。 结论: 加味四逆散能调节慢性束缚应激反应海马部分氨基酸水平,防止兴奋性氨基酸的神经毒性作用。 相似文献
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目的:探讨不同组织病理分级的脑星形细胞瘤中血管内皮生长因子受体3(Flt-4又称VEGFR-3)的表达意义。 方法: 采用免疫组织化学方法,检测50例不同级别脑星形细胞瘤患者手术切除标本中Flt-4、血管内皮生长因子(VEGF)的表达,并用抗FⅧ因子抗体标记瘤组织血管内皮细胞,计算肿瘤内微血管密度(IMVD)。 结果: Flt-4、VEGF总阳性表达率分别为52%(26/50)、60%(30/50)。Flt-4、VEGF均与脑星形细胞瘤病理分级呈显著正相关(等级相关系数分别为0.359、0.360,P<0.05)。 结论: 脑星形细胞瘤中有Flt-4表达,主要表达于血管内皮细胞和部分肿瘤细胞,Flt-4既可是内皮细胞自分泌产生,部分还可来自瘤细胞的旁分泌;脑星形细胞瘤中Flt-4阳性表达的脉管是血管;Flt-4的表达与星形细胞瘤的病理分级相关 相似文献
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Can Ding Rolf Beetz Gabriele Rittner Oliver Bartsch 《American journal of medical genetics. Part A》2020,182(5):1032-1040
There are two forms of diabetes insipidus, central (neurohypophyseal), and nephrogenic, caused by pathogenic variants in the AVP gene and the AVPR2 or AQP2 genes, respectively. We report on a four‐generation family, seven individuals had central diabetes insipidus (CDI) and the female index patient seen from age 16 to 26 years had (mild) nephrogenic diabetes insipidus. In her father with CDI, a known pathogenic heterozygous AVP variant c.232_234del p.(Glu78del) was identified, confirming the diagnosis of CDI in him and the other affected family members. In the proband, molecular analysis disclosed a novel heterozygous AVPR2 gene variant, c.962A > T p.(Asn321Ile) and an extremely skewed X‐inactivation, confirming X‐linked nephrogenic diabetes insipidus (XL‐NDI). Whole exome sequencing showed no further causative mutation. This is the first report on the co‐existence of CDI and NDI in one family. Our review of symptomatic female AVPR2 heterozygotes includes 23 families with at least one affected female (including this study). There were 21 different causative mutations. Mutation types in females did not differ from those in males. Both severe XL‐NDI and mild forms were reported in females. All six females with severe XL‐NDI had complete loss‐of‐function (null) mutations. The remaining 17 female probands had milder XL‐NDI caused by 14 missense variants and three null variants of the AVPR2 gene. X‐inactivation was studied in nine of these females; all showed extreme or slight skewing. The review underlines that XL‐NDI in female AVPR2 heterozygotes is always accompanied by skewed X‐inactivation, emphasizing a need for X‐inactivation studies in these females. 相似文献
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To compare morphological changes in the umbilical cords from chronic hypertensive and preeclamptic patients having normal or pathological umbilical artery Doppler ultrasonographic results. Umbilical cords from 34 normotensive, 31 chronic hypertensive and 70 preeclamptic women with normal and abnormal Doppler flow velocity waveforms (FVW) at 35-40 gestational weeks were studied. Morphological changes in the umbilical cords were examined on formalin-fixed, paraffin-embedded sections. The total umbilical cord area, total vessel area, and wall thickness of umbilical vessels were measured in systematic random samples using unbiased stereology methods. An ANOVA test was used for statistical analysis. In the chronic hypertensive and preeclamptic groups with normal Doppler FVW, the thickness of the umbilical cord vessels remained nearly constant, whereas both the total area and the lumen area were reduced. These changes correlate with the histopathological findings, suggesting a mainly vasoconstrictive effect. By contrast, analysis of the preeclamptic group with pathologic Doppler FVW showed a comparable reduction of all parameters of the umbilical cord. Histopathological findings were related to smaller, contracted smooth muscle cells of the vessel wall, which is suggestive of a predominant hypoplastic mechanism. As a result of reduced uteroplacental perfusion, fetal hypoxia and intrauterine growth retardation become unavoidable in preeclampsia. The histopathological changes in the umbilical cord between the chronic hypertensive and preeclamptic patients depend on the Doppler results. In conclusion, the umbilical artery Doppler FVW indices provide good values for predicting intrauterine growth retardation in preeclamptic patients. 相似文献