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51.
雷公藤多甙对蟾蜍缝匠肌终板膜乙酰胆碱受体的作用   总被引:2,自引:1,他引:2  
目的 观察雷公藤多甙(TWP)对终板膜乙酰胆碱受体(nAChR)的反应性的作用。方法 在不均匀牵张法制动的蟾蜍缝匠肌标本上,利用微电泳氯化及乙酰胆碱(AChCl)技术,在终板区引起的乙酰胆碱电位(AChP)来板映终板膜nAChP的反应性。结果 (1)20g L TWP组,用药20min后AChP振幅明显升高,40mg/L和60mg/LTWP组,用药10min后AChP振幅明显升高。(2)20mg/L和40mg/L TWP组内,AChP振幅除80min组外,其它各时间组间有显著性差异(P<0.05),60min达最大值;(3)60mg/L TWP组,在用药后40min,60min和80min均记录到动作(AP);(4)药物各浓度组引起的AChP振幅变化率之间有显著差异(P<0.05),其中60mg/L TWP组引起的变化率最大。结论 TWP能提高终板膜nAChR的反应性,并有明显的量效关系和一定的时效关系。  相似文献   
52.
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   
53.
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   
54.
目的:探讨急性心肌缺血再灌注早期不同时间心肌细胞内Fos蛋白表达的变化,为心肌早期缺血再灌注损伤致死死后诊断提供新方法。方法:在32只SD大鼠建立心肌早期缺血再灌注损伤模型,另外40只大鼠分为正常与缺血对照组。用免疫组化SABC法结合图象分析研究心肌细胞核Fos蛋白的累积情况。结果:缺血30min再灌注30min后,再灌注区有部分心肌细胞核呈弱阳性着色,以后随缺血时间延长核阳性增强。缺血90min再灌注30min后核棕褐色染色最强,180min后又开始减弱。正常和单纯缺血组心肌细胞核未见有阳性反应。HE染色无明显病理改变。结论:Fos蛋白表达高峰在缺血90~180min之间,FosSABC染色法可诊断缺血30min再灌注30min或更长时间的损伤。免疫组化染色法检测心肌细胞核Fos蛋白的表达有望成为急性心肌缺血再灌注死后诊断的一种有意义的手段。  相似文献   
55.
目的:探讨Geminin基因沉默对人脑胶质瘤细胞恶性生物学行为的影响及可能的发生机制.方法:选取南通大学附属医院脑外科2018-2019年手术切除的20例神经胶质瘤患者的新鲜标本,qRT-PCR结合基因表达谱数据动态分析(gene expression profilling interactive analysis,G...  相似文献   
56.
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   
57.
58.
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   
59.
60.
The macromorphic properties of carbon nanotubes perform poorly because of their size limitations: nanosize in diameters and microsize in length. In this work, to realize these dual purposes, we first used an electrochemical method to tear the surface of multiwalled carbon nanotubes (MWCNTs) to anchor photonic Eu3+-complexes there. Through the polar reactive groups endowed by the tearing, the Eu3+-complexes coordinate at the defected structures, obtaining the Eu3+-complex-anchored, unzipped, multiwalled carbon nanotubes (E-uMWCNTs). The controllable surface-breaking retains the MWCNTs’ original, excellent mechanical properties. Then, to obtain the macromorphic structure with infinitely long fibers, a wet-spinning process was applied via the binding of a small quantity of polyvinyl alcohol (PVA). Thus, the wet-spun fibers with high contents of E-uMWCNTs (E-uMWCNT-Fs) were produced, in which the E-uMWCNTs took 33.3 wt%, a high ratio in E-uMWCNT-Fs. On the other hand, due to the reinforcing effect of E-uMWCNTs, the highest tensile strength can reach 228.2 MPa for E-uMWCNT-Fs. Meanwhile, the E-uMWCNT-Fs show high-efficiency photoluminescence and excellent media resistance performance due to the embedding effect of PVA on the E-uMWCNTs. Therefore, E-uMWCNT-Fs can exhibit excellent luminescence properties in aqueous solutions at pH 4~12 and in some high-concentration metal-ion solutions. Those distinguished performances promise outstanding innovations of this work.  相似文献   
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