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31.
结直肠癌缺失(deleted in colorectal carcinoma, DCC)基因是于1990年确定并命名的重要的肿瘤抑癌基因,定位于人染色体18q21.3.DCC蛋白具有跨膜分子特征,其胞外部分氨基酸排序与神经细胞黏附分子相似.细胞黏附分子介导细胞间、细胞与基质间的相互作用,促进细胞与细胞间的黏附,是维持细胞生长的重要条件之一.有研究表明,良性卵巢肿瘤组织中DCC基因的表达缺失率为20%,恶性卵巢肿瘤组织中DCC基因的表达缺失率为56%,两者比较差异有显著意义.在临床分期晚、组织分化差、盆腹腔有转移的卵巢恶性肿瘤中DCC基因表达缺失率更高. 相似文献
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目的研究体内成熟与体外成熟卵母细胞的纺锤体位置及其与胚胎发育的关系。方法对134个体内成熟卵母细胞在卵母细胞胞质内单精子注射法(ICSI)操作时用纺锤体实时观察仪进行纺锤体位置的观察,体内成熟卵母细胞来自单纯因男性不育而进行ICSI治疗的患者15例(体内成熟组)。另外对45个体外成熟的卵母细胞观察纺锤体位置,体外成熟卵母细胞来自因多囊卵巢综合征致不孕而进行治疗的患者5例(体外成熟组)。纺锤体的位置按照其与第一极体之间的角度不同分为Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ级。并观察两组成熟卵母细胞的受精及其胚胎发育情况。结果体内成熟组和体外成熟组患者的卵母细胞中可观察到纺锤体的分别占83.6%(112/134)和82.2%(37/45)。体内成熟组患者卵母细胞纺锤体的位置Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ级分别为22.4%、55.2%、3.O%、3.O%、16.4%,体外成熟组则分别为17.8%、51.1%、8.9%、4.4%、17.8%,两组各级间分别比较,差异均无统计学意义(P〉0.05)。在体内成熟组卵母细胞中,纺锤体离第一极体较近(Ⅰ级)者受精率较高(93.3%),显著高于其他各级(分别为73.0%、2/4、1/4、63.6%,P〈0.05)。结论体内成熟与体外成熟卵母细胞间纺锤体位置未见显著差异;纺锤体的位置与卵母细胞受精率有一定相关性。 相似文献
34.
Tumor lymphangiogenesis and lymphangiogenic growth factors 总被引:2,自引:0,他引:2
Recent studies have revealed that malignant tumors can actively induce the formation of new lymphatic vessels and metastasize through the lymphatic system. Tumor-induced lymphangiogenesis driven by tumors expressed lymphangiogenic growth factors such as VEGF family, fibroblast growth factor 2 (FGF-2), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), and platelet-derived growth factors (PDGFs) is correlated with lymph node metastasis in experimental cancer models and in several types of human cancers. Tumor- induced lymphangiogenesis has now been firmly established as a novel mechanism for cancer progression and lymph node metastasis. Recent studies indicate that blockade of the lymphangiogenic growth factors pathway inhibits tumor spread to lymph nodes and likely beyond. The potential effects of most of these newly identified lymphatic growth factors on tumor-induced lymphangiogenesis and lymph node metastasis remain to be further investigated. A number of questions remain to be answered concerning the potential efficacy of targeting at tumor-induced lymphangiogenesis for inhibiting tumor spread to lymph nodes. 相似文献
35.
随着中医药事业的发展,中药剂型的不断改革,中药针剂日益广泛地应用于临床脑血管疾病,在疾病的治疗中发挥了一定的作用.与此同时,其不良反应(ADR)的报道也随之增多,其中以中、重度ADR为主,占ADR总数1/3以上. 相似文献
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Shuting Si Zhicheng Peng Haoyue Cheng Yan Zhuang Peihan Chi Xialidan Alifu Haibo Zhou Minjia Mo Yunxian Yu 《Nutrients》2022,14(12)
The association between vitamin D and hemoglobin has been suggested. Vitamin D can affect erythropoiesis by the induction of erythroid progenitor cell proliferation and enhance iron absorption by regulating the iron-hepcidin-ferroportin axis in monocytes. However, this relationship in pregnant women is scarce. The purpose of this study was to investigate the association between plasma vitamin D levels with hemoglobin concentration in pregnant women considering each trimester and iron supplementation. The data were obtained from Zhoushan Pregnant Women Cohort, collected from 2011 to 2018. Plasma 25(OH)D was measured in each trimester using liquid chromatography–tandem mass spectrometry. Generalized estimating equations and multiple linear regressions were performed. Finally, 2962 pregnant women and 4419 observations in the first trimester were included in this study. Plasma 25(OH)D in first trimester (T1) (β = 0.06, p = 0.0177), second trimester (T2) (β = 0.15, p < 0.0001), and third trimester (T3) (β = 0.12, p = 0.0006) were positively associated with Hb. Association between plasma 25(OH)D levels in T1 and Hb concentration was positively associated with gestational age (β = 0.005, p = 0.0421). Pregnant women with VD deficiency in T1 (OR = 1.42, 95% CI: 1.07–1.88) or T2 (OR = 1.94, 95% CI: 1.30–2.89) presented an increased risk of anemia, compared with women without VD deficiency. Moreover, the significant relationship between VD and Hb was only observed among women with iron supplementation during pregnancy. Plasma 25(OH)D levels in each trimester were positively associated with Hb concentration. Iron supplementation might be an important factor affecting the relationship between VD and Hb. 相似文献
38.
目的:探讨倍频Nd:YAG激光光凝对不同分期糖尿病视网膜病变患者视力康复的影响。方法:根据DRPSG(diabetic retinopathy photocoagulation study group)制定的治疗技术规定,对219例368眼分别为增殖前期糖尿病视网膜病变(PPDR)和增殖期糖尿病视网膜病变(PDR)用倍频Nd:YAG激光行全视网膜光凝治疗,术后3,6,12mo后复查眼底荧光血管造影。结果:PPDR患者视力提高和不变者占77.6%,PDR患者视力提高和不变者占83.4%,而高危PDR患者视力提高和不变者占65.2%。结论:倍频Nd:YAG激光治疗DR是安全有效的,选择合适的时机和合理的激光参数对不同分期DR行全视网膜光凝是确保DR患者视力康复的关键。 相似文献
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The integrated process of design and fabrication is invariably of particular interest and important to improve the quality and reduce the production cycle for structural joints, which are key components for connecting members and transferring loads in structural systems. In this work, using the generative design method, a pioneering idea was successfully realized to attain a reasonable configuration of the cross joints, which was then consecutively manufactured using 3D printing technology. Firstly, the initial model and generation conditions of a cross joint were constructed by the machine learning-based generative design algorithm, and hundreds of models were automatically generated. Then, based on the design objective and cost index of the cross joint, three representative joints were selected for further numerical analysis to verify the advantages of generative design. Finally, 3D printing was utilized to produce generative joints; the influences of printing parameters on the quality of 3D printing are further discussed in this paper. The results show that the cross joints from the generative design method have varied and innovative configurations and the best static behaviors. 3D printing technology can enhance the accuracy of cross joint fabrication. It is viable to utilize the integrated process of generative design and 3D printing to design and manufacture cross joints. 相似文献