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1.
Low serum VEGF levels are associated with Alzheimer's disease   总被引:4,自引:0,他引:4  
OBJECTIVE: As vascular endothelial growth factor (VEGF) determines important neurotrophic and neuroprotective actions, we postulated serum VEGF levels could be abnormally low in patients with Alzheimer's disease (AD). METHODS: We measured serum VEGF levels (VEGF(165) isoform by ELISA) in 51 patients with AD by National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorder Association criteria and compared with 66 age- and gender-matched non-demented controls. Patients with AD were stratified into levels of dementia severity by the Clinical Dementia Rating scale. Serum VEGF levels were stratified into upper (>309 pg/ml), middle (207-309 pg/ml), and lower (<207 pg/ml) tertiles. VEGF (-2,578) (rs 699,947) and VEGF (-634) (rs 2,010,963) polymorphisms were genotyped in patients with AD and controls. RESULTS: The mean concentration of VEGF in the serum of patients with AD (215.9 pg/ml, SD 101.5) was significantly lower than that of the controls (308.6 pg/ml, SD 223.9, P = 0.004), and decreased serum VEGF levels were associated with AD in a dose-dependent manner, the lower tertile of serum VEGF levels being associated with a fivefold increased risk for AD when compared with the upper tertile. There was no significant correlation between serum VEGF levels and age, sex, APOE alleles, AD dementia severity nor VEGF gene polymorphisms. CONCLUSION: Decrease in serum VEGF levels could contribute to the neurodegenerative process in AD.  相似文献
2.
Growth of solid tumors is highly dependent on angiogenesis. During tumor development, neoplastic cells switch to an angiogenic phenotype, playing a significant role in the expression of the vascular endothelial growth factor (VEGF). Seventy-two brain gliomas were induced in Sprague Dawley rats by prenatal exposure to ethylnitrosourea (ENU). Screening and location of tumors was carried out using magnetic resonance imaging (MRI). Conventional histology and immunocytochemistry for antibodies against glial fibrillary acidic protein (GFAP), S-100, NF, oligodendrocyte Ab-2, Ki-67, and VEGF165 were performed. The proliferation index (PI) was calculated from the Ki-67 labeling index, and the concentration of VEGF165 was quantified by enzyme-linked immunosorbent assay (ELISA). In vivo identification of macro- and microtumor appears to be useful to lead morphological and biochemical studies. Histopathology allows us to identify microtumors as classic oligodendrogliomas (CO; mean PI of 6.01 +/- 2.8%) and macrotumors as anaplastic oligodendrogliomas (AO; mean PI of 14.06 +/- 5%). Classic oligodendrogliomas show scarce VEGF165 expression whereas anaplastic ones display VEGF165 protein level 100-fold increased respect to CO. Astrocytes, neoplastic, and endothelial cells show differential immunostaining patterns from the border to the core of neoplasm. Positive structures for VEGF and their distribution vary according to PI increase. Anaplastic gliomas displaying VEGF-positive intratumor capillaries correspond to the highest PI values. To identify the "angiogenic switch," we propose the glioma stage characterized by VEGF immunopositive neoplastic cells inside the tumor and positive endothelial cells surrounding it.  相似文献
3.
VEGF、MMP-9在人脑胶质瘤中的表达及其意义   总被引:3,自引:0,他引:3  
目的探讨血管内皮细胞生长因子(VEGF)、基质金属蛋白酶-9(MMP-9)在人脑胶质瘤中的表达及其与血管生成、瘤周水肿(PTBE)和肿瘤恶性程度的关系。方法采用免疫组化方法分别检测30例经手术和病理证实的脑胶质瘤瘤体和瘤周水肿区中VEGF、MMP-9的表达;通过计数微血管密度(MVD)来评估血管生成情况;根据CT和MRI的结果测定水肿指数;同时用透射电镜对瘤体区及瘤周水肿区的超微结构进行观察。6例来自颅脑损伤病人的正常脑组织作为对照。结果随着肿瘤级别增加MVD逐渐升高,在高级别胶质瘤体中MVD显著高于瘤周(P〈0.01);VEGF、MMP-9表达与胶质瘤中的MVD均呈显著正相关(P〈0.01),且两者与胶质瘤的水肿指数(EI)也均呈显著正相关(P〈0.01);高级别胶质瘤的EI显著高于低级别胶质瘤(Ⅰ级、Ⅱ级)(P〈0.05)。电镜下水肿明显者微血管内皮细胞胞浆内有较多小泡囊状细胞器和基底膜中有较多虫蚀样空洞等。结论 VEGF、MMP-9可能共同参与了脑胶质瘤血管生成和脑水肿的发生,并促进肿瘤的侵袭性生长。  相似文献
4.
VEGF在人胚胎干细胞向神经元分化中作用的研究   总被引:3,自引:1,他引:2  
目的观察血管内皮生长因子(vascular endothelial growth factor,VEGF)在人胚胎干细胞分化为神经元过程中是否发挥作用及相关机制。方法人胚胎干细胞经拟胚体向神经元分化,分为3组:A组为常规诱导组,B组为常规诱导+VEGF(10ng/mL)作用组,C组为常规诱导+VEGF(10ng/mL)+VEGFR2/Fc嵌合体(10ng/mL)作用组;用RT-PCR、免疫荧光法检测各阶段细胞标志物,计算并用流式细胞仪检测各组不同阶段细胞阳性率。结果用RT-PCR分别检测到OCT4、Nestin、MAP2表达;免疫荧光法检测显示B组产生神经干细胞、分化为神经元的阳性率明显高于A、C两组,差异有统计学意义(P〈0.01),A、C两组之间无显著性差异(P〉0.05);流式细胞仪检测与免疫荧光法相似。结论人胚胎干细胞体外分化过程中血管内皮生长因子通过血管内皮生长因子受体2来促进神经干细胞增殖及向神经元分化。  相似文献
5.
转基因组织工程骨体内移植修复颅骨缺损的实验研究   总被引:3,自引:0,他引:3  
目的 采用血管内皮生长因子(VEGF)转基因组织工程骨对兔颅骨缺损模型进行修复,对转基因技术在颅骨组织工程方面的应用进行初步探讨.方法 建立兔颅骨缺损模型,以转基因MSCs与成骨诱导后的MSCs混合作为种子细胞构建的组织工程骨进行移植修复,以单纯组织工程骨为对照.通过血生化检查、组织学观察、X线检查以及组织学评分等指标来判断修复效果.结果 转基因组织工程骨较单纯组织工程骨成骨细胞生长、增殖、血管形成更活跃,其成骨能力明显增强.结论 VEGF转基因组织工程骨能加快修复区的骨形成,可望为临床大块颅骨缺损修复提供有效方法.  相似文献
6.
BACKGROUND: In cardiovascular disease, soluble CD40 ligand (sCD40L) has been associated with an adverse prognosis. Angiogenesis has been implicated in the progression of coronary artery disease (CAD) and sCD40L has pro-angiogenic effects in vitro. Angiogenesis itself is regulated by many mediators, such as vascular endothelial growth factor (VEGF) and the angiopoietins (Ang). Ang-1 promotes vascular maturation whilst Ang-2 destabilises the blood vessel and permits vascular growth with VEGF. Hence, selective elevation of VEGF and Ang-2 suggest a state of vascular plasticity and increased angiogenesis. We hypothesised raised plasma levels of VEGF and Ang-2, but not Ang-1, and correlations with raised sCD40L levels and CAD severity/collateralisation in patients with CAD. METHODS: We recruited 153 patients attending diagnostic angiography for CAD and 47 healthy controls. Patients with previous revascularisation or unequivocally normal angiograms were excluded. The coronary atheroma score (CAS) and coronary stenosis score (CSS), and the presence of collaterals, were assessed by 2 blinded observers. Plasma sCD40L, VEGF, Ang-1 and -2 levels were measured by ELISA. RESULTS: Plasma levels of sCD40L, VEGF and Ang-2, but not Ang-1, were higher in CAD patients compared to controls. Both plasma VEGF (r=0.526, p<0.001) and Ang-2 (r=0.429, p<0.001) were correlated with sCD40L, but not with CAS, CSS or collateralisation. On stepwise multivariate regression analysis, plasma sCD40L was an independent predictor of plasma VEGF (p=0.002), and Ang-2 (p<0.001) levels. CONCLUSION: These data suggest abnormal indices of angiogenesis in CAD, which may be associated with increased CD40-CD40L interactions in patients with CAD. Plasma sCD40L, VEGF and Ang-2 levels were not correlated to angiographic CAD/collateralisation.  相似文献
7.
目的 探讨基质金属蛋白酶(MMP)-2、-8和血管内皮生长因子(VEGF)在人颈动脉粥样硬化不稳定斑块中与平滑肌细胞、内皮细胞以及炎细胞的定位共表达特点.方法 应用HE染色对手术切除的6例动脉粥样硬化(AS)患者不稳定斑块标本进行组织学观察、筛选,然后利用免疫荧光双标技术和激光共聚焦显微镜观察MMP-2、-8和VEGF在人不稳定斑块上的定位共表达情况.结果 所有标本均有AS斑块的组织学特征,且均为Ⅳ型以上的不稳定性斑块;MMP-2在单核细胞浸润的斑块纤维帽平滑肌细胞和肩部单核细胞中表达最为显著,在肩部和脂质坏死区边缘增生微血管内皮细胞中也有较多表达;MMP-8表达最多见于纤维帽和脂质核心内的单核细胞中,其次共表达在纤维帽的平滑肌细胞中;VEGF在肩部增生的微血管内皮细胞中表达最为明显,由平滑肌细胞构成的纤维帽和有较多单核细胞浸润的脂质坏死区边缘也是VEGF的高表达区域.结论 MMP-2、-8和VEGF可以与人不稳定斑块中的单核细胞、平滑肌细胞和内皮细胞明显共表达,表达区域主要集中在单核细胞浸润明显的斑块纤维帽、肩部以及脂质坏死区边缘新生微血管周围.  相似文献
8.
PTTG、MMPs、VEGF在侵袭性垂体腺瘤中的表达及其意义   总被引:2,自引:2,他引:0  
目的研究垂体瘤转化基因(PTTG)蛋白、基质金属蛋白酶(MMPs)和血管内皮生长因子(VEGF)在垂体腺瘤中的表达及其相关性,以及它们与垂体腺瘤生物学行为的关系。方法垂体腺瘤组织标本50例,其中侵袭性26例,非侵袭性24例,利用免疫组化Envision二步法检测并分析比较PTTG、MMP-2、MMP-9及VEGF在侵袭性垂体腺瘤和非侵袭性垂体腺瘤中的表达。结果侵袭性垂体腺瘤中PTTG、MMP-2、MMP-9及VEGF的表达均高于非侵袭性垂体腺瘤(P〈0.05);在侵袭性垂体腺瘤中PTTG和VEGF与MMP-2、MMP-9的表达水平均呈正相关(P〈0.01)。结论垂体腺瘤的侵袭性与PTTG、MMPs、VEGF的过度表达有关,PTTG、MMPs可作为辅助诊断侵袭性垂体腺瘤的一项生物学指标。  相似文献
9.
CXCR4活化促进人恶性胶质瘤细胞分泌血管生成因子   总被引:2,自引:0,他引:2  
目的观测CXCR4活化对人恶性胶质瘤细胞系U87中血管内皮生长因子(VEGF)、白细胞介素-8(IL-8)基因表达及蛋白分泌的影响。方法采用间接免疫荧光标记观测CXCR4在U87细胞中的表达和定位;用间质细胞衍生因子-1α(SDF-1α)激活CXCR4,通过酶联免疫吸附试验(ELISA)检测U87细胞培养上清中VEGF、IL-8蛋白的含量,用逆转录聚合酶链反应(RT-PCR)检测二者mRNA的表达。结果CXCR4表达于U87细胞的胞膜和胞质,经活化后可增加VEGF、IL-8mRNA的表达和蛋白分泌量。结论人恶性胶质瘤细胞中CXCR4活化后能够促进血管生成因子VEGF和IL-8的产生。  相似文献
10.
目的 探讨血管内皮生长因子(VEGF)基因修饰神经干细胞(NSC)移植治疗脑梗死大鼠模型的治疗效果,以及基因的表达情况和神经保护作用。方法 通过移植腺病毒载体介导的VEGF165基因转染的C17-2NSC到大鼠大脑中动脉阻断(MCAO)的局灶性脑缺血模型脑梗死半暗带区,观察移植后大鼠神经功能变化,神经特异性烯醇化酶(NSE)、CD31免疫组化检查观察细胞存活分化和血管新生情况。结果 VEGF病毒组、NSC移植组和VEGF基因修饰NSC组神经功能严重度评分均较对照组显著减少(P〈0.05),以VEGF基因修饰NSC组最为显著(P〈0.05);NSC移植后NSE阳性细胞数较对照组显著增多(P〈0.05),VEGF基因修饰NSC组更为碌著(P〈0.05);VEGF病毒组和VEGF基因修饰NSC移植组脑梗死灶周围血管数较对照组显著增多(P〈0.05),以VEGF基因修饰NSC组更为显著(P〈0.05)。结论 转染VEGF基因的C17.2NSC脑内移植治疗MCAO脑梗死模型可促进NSC向神经元分化,可促进新生血管形成,改善神经功能。VEGF基因修饰NSC移植治疗效果优于单纯的C17.2NSC移植或VEGF基因治疗。  相似文献
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