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31.
miR-21 has been shown to play fundamental role in diverse biological and pathological processes, including fibrotic diseases. In the present study, we investigated whether miR-21 regulated the fibrogenic epithelial-mesenchymal transition (EMT) in human hepatocytes QSG-7701 and explored underlying mechanisms. The results showed that treatment of QSG-7701 cells with pro-fibrogenic factor TGF-β1 resulted in increased expression of miR-21 and promoted fibrogenic EMT in hepatocytes. Downregulation of miR-21 expression by transfection of anti-miR-21 into QSG-7701 cells inhibited fibrogenic EMT induced by TGF-β1. Furthermore, overexpression of miR-21 alone also resulted in EMT-like transformation in QSG-7701 cells. TGF-β1 treatment resulted in decreased PTEN and increased Akt phosphorylation and anti-miR-21 abolished this effect. Overexpression of miR-21 in QSG-7701 cells also downregulated PTEN and upregulated Akt phosphralation. Inhibition of Akt signaling by specific inhibitor Akt inhibitor IV blocked TGF-β1 and miR-21-induced fibrogenic EMT. In summary, our results identify miR-21 as a key regulator of fibrogenic EMT in hepatocytes via PTEN/Akt pathway. Targeting miR-21 may provide a new therapeutic strategy against hepatic fibrosis.  相似文献   
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目的:探讨趋化因子CCL21、E选择素(E-selectins)、热休克蛋白90(heat shock protein 90,Hsp90)在实验性牙周炎大鼠牙周组织中的表达及意义。方法:选取40只10周龄雄性Wistar大鼠,随机分为4组,每组10只。A、B、C组均建立牙周炎模型,其余10只为空白对照组。A、B、C组分别于牙周基础治疗后4、8、12周处死并取第一、二磨牙间牙周组织进行CCL21、E-selectins、Hsp90 mRNA 和蛋白表达检测。采用SPSS 25.0软件包对数据进行统计学分析。结果:A、B、C组牙周附着水平显著大于对照组(P<0.05);牙周基础治疗后,牙周附着水平呈先升高后降低趋势,牙周组织中CCL21、E-selectins、Hsp90 mRNA以及蛋白相对表达量呈降低趋势(P<0.05)。结论:CCL21、E-selectins、Hsp90 mRNA在牙周炎组织中表达上调,随着牙周局部治疗,其表达水平逐渐降低。  相似文献   
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Background and purposeGiven the overlapping clinical manifestations and pathology, the differentiation between essential tremor (ET) and Parkinson's disease (PD) is difficult. Our aims were to examine the plasma metabolomics profiling and their association with motor and non-motor symptoms (NMS) in patients with PD, and to determine differences between de novo PD compared to moderate-advanced PD vs. controls and patients with ET.MethodsPlasma samples were collected from 137 subjects including 35 age matched controls, 29 NOVO-PD, 35 PD and 38 ET patients. PD severity, motor and NMS including cognitive function were assessed using the UPDRS, NMS and PD cognitive rating scales, respectively. Metabolomics analysis was performed by UPLC-ESI-QToF-MS followed by unsupervised multivariate statistics. The area under the curve of the biomarkers according to distribution of their concentrations and the diagnosis of PD (NOVO-PD, advanced PD) vs ET and healthy controls was used as a measurement of diagnostic ability.ResultsSeveral acyl-carnitines, bilirubin, tyramine and tetrahydro-21-deoxycortisol (THS) presented good predictive accuracy (AUC higher than 0.8) for differentiating de novo PD and advanced PD from controls and ET, suggesting an alteration in the lipid oxidation pathway. In multivariate regression analysis, metabolite levels were not significantly associated with motor and NMS severity in PD.ConclusionsDiverse acyl-carnitines, bilirubin, tyramine and some adrenal gland derived metabolites are suggested as potential biomarkers able to distinguish between PD from controls and ET.  相似文献   
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目的:探讨黄芪甲苷对肾癌细胞增殖、凋亡的影响及其作用机制。方法:用终浓度为20 μmol/L、40 μmol/L、80 μmol/L、160 μmol/L的黄芪甲苷处理肾癌细胞A498作为不同浓度黄芪甲苷处理组,正常培养的细胞作为对照(NC)组;将anti-miR-con、anti-miR-21转染至细胞A498中,记为anti-miR-con组、anti-miR-21组;将miR-con、miR-21转染至细胞A498中再用80 μmol/L黄芪甲苷处理作为HSJG+miR-con组、HSJG+miR-21组。四甲基偶氮唑盐比色法(MTT)检测细胞存活率;蛋白质印迹(Western Blot)检测裂解半胱氨酸天冬氨酸蛋白酶-3(Cleaved-caspase-3)、细胞周期蛋白D1(Cyclin D1)蛋白表达水平;流式细胞术检测细胞凋亡;实时荧光定量PCR(RT-qPCR)检测miR-21表达水平。结果:与对照组相比,不同浓度黄芪甲苷处理组肾癌细胞A498中细胞存活率显著降低,Cyclin D1表达水平显著降低,Cleaved-caspase-3表达水平显著升高,细胞凋亡率显著升高,小鼠肿块重量显著降低,miR-21表达水平显著降低(P<0.05)。miR-21低表达Cyclin D1表达水平显著降低,Cleaved-caspase-3表达水平显著升高,细胞存活率显著降低,细胞凋亡率显著升高(P<0.05)。miR-21高表达逆转了黄芪甲苷对肾癌细胞A498增殖抑制和凋亡促进的作用。结论:黄芪甲苷可抑制肾癌细胞A498增殖,促进细胞凋亡,抑制肾癌实体瘤的生长,其机制可能与miR-21表达水平有关。  相似文献   
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Breast cancer (BC) is the most frequent tumor in women and genetic factors are among the main risk factors contributing to this malignancy. Chromosome 9p21 contains important regulatory non-coding RNAs and is associated with multiple malignancies including BC. The current meta-analysis aimed to investigate the association between genetic variants within the 9p21 locus and risk of breast cancer. A literature search was performed using PubMed, Web of Science, Embase, MEDLINE, Scopus and Clinical key databases. Nine studies containing 23,726 subjects were eligible for the final analysis and specific odds ratios (OR) and confidence intervals (95% CI) were evaluated to assess the strength of the associations. In the pooled analysis, there was an association between the genetic variations in 9p21 locus (CDKN2A/2B) with risk of breast cancer with a standard OR of 1.22 (95% CI: 1.04–1.45, P = 0.016; random-effects model), supporting the significance of this locus as a novel risk factor for breast cancer patients. In conclusion, our results showed that 9p21 region is positively associated with risk of BC and its polymorphisms may be a candidate marker for BC susceptibility.  相似文献   
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BackgroundHigh levels of interleukin 17 are expressed in active Behcet’s disease (BD) patients. High miRNA-499 relative expression is known to be associated with vascular manifestations and aneurysms in BD.Aim of the workTo detect miRNA-499 relative expression and interleukin 17 serum levels in BD patients and find their association to clinical characteristics and disease activity.Patients and methodsBlood samples were obtained from 40 Egyptian BD patients and 40 matched controls. The BD current activity form (BDCAF) was estimated. Relative expression of miRNA-499 was measured by real-time polymerase chain reaction. Serum IL-17 was also measured in by enzyme-linked immunosorbent assay.ResultsThe mean age of the patients was 34.4 ± 10.9 years, disease duration was 8.9 ± 0.8 years and age at onset was 25.5 ± 7.2 years and they were 33 males and 7 females. All patients had oral ulcers, 85% had genital ulcers and 75% had ocular manifestations. The mean BDCAF was 1.54 ± 1.78. Levels of miRNA-499 relative expression were significantly higher in BD cases versus controls (4.2 ± 2.1 vs. 1.1 ± 0.3ΔΔCt respectively; p < 0.001). Levels of IL 17 were significantly higher in BD cases versus controls (86.9 ± 31.2 vs. 34.7 ± 4.4 pg/ml respectively; p < 0.001). There was a non-significant correlation between miRNA and IL 17 in patients (r = −0.06, p < 0.71). IL17 was significantly associated only with the occurrence of arthritis (p = 0.03). There was no significant association between miRNA-499 or IL-17 with the BDCAF (r = 0.22, p = 0.12 and r = −0.002, p = 0.99; respectively).ConclusionMicro RNA-499 relative expression and IL17 levels were significantly higher in BD patients compared to the controls.  相似文献   
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目的 探讨MicroRNA-21(miR-21)对视网膜母细胞瘤(RB)细胞增殖的影响及作用机制。方法 采用Real-time PCR技术检测miR-21在正常视网膜组织和确诊RB组织中的表达情况;然后在转染的基础上运用MTT检查RB细胞存活率、流式细胞仪检测细胞凋亡率。Western blot法检测与细胞凋亡相关蛋白PDCD4、Bax、Bcl-2的表达。结果 与正常视网膜组织miR-21表达 (0.703±0.071)相比,RB组织miR-21为高表达(2.214±0.162),差异有统计学意义(P<0.01)。在Weri-Rb-1细胞中,与NC组(2.245±0.213)相比,miR-21抑制剂转染后明显降低了miR-21的表达水平,miR-21 inhibitor组为0.683±0.075,差异有统计学意义 (P<0.01)。两组细胞转染后24 h、48 h、72 h、96 h,MTT测定法检测细胞活力结果显示:两组24 h的A值比较,差异无统计学意义 (P>0.05),miR-21 inhibitor 组在 48 h、72 h、 96 h的A值均低于 NC 组,差异均有统计学意义 (均为P<0.01)。流式细胞术检测结果显示:NC组凋亡细胞在总细胞中百分比为(3.045±0.301)%和(4.832±0.493)%,miR-21 inhibitor组凋亡细胞在总细胞中百分比为(2.593±0.257)%和(40.167±4.014)%,miR-21 inhibitor组Weri-Rb-1细胞的凋亡率明显高于miR-21 NC组(P<0.01)。Western blot检测结果显示:NC组PDCD4表达(0.192±0.045)相比miR-21 inhibitor组(0.683±0.091)表达明显减少,NC组Bax的蛋白表达水平(0.143±0.036)相比miR-21 inhibitor组(1.192±0.054)也明显减少,差异均有统计学意义(P<0.01),NC组Bcl-2蛋白表达(0.864±0.038)相比miR-21 inhibitor组(0.257±0.026)明显增多,差异有统计学意义(P<0.05)。结论 miR-21是RB的促癌基因,miR-21抑制剂可以通过降低miR-21表达抑制肿瘤细胞的增殖、促进细胞凋亡,这一过程与PDCD4、Bax、Bcl-2等凋亡相关蛋白有关。  相似文献   
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