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91.
There is strong evidence to suggest that inflammatory responses link obesity and diseases, and the understanding of obesity-induced inflammatory mechanisms is central to the pathogenesis of diseases such asnonalcoholic fatty liver disease(NAFLD) and atherosclerosis that are modified by obesity. Based on this, anti-inflammatory treatments become a potential therapies for obesity-related diseases like NAFLD.A critical role of toll-like receptor (TLR) and its downstream molecules such as tumor necrosis factor receptor-associated factor 6(TRAF6) has been documented in inflammatory response induced by fatty acid. TLR pathway regulation provides a new insight to controlling the inflammatory response induced by fatty acid. Taken together, our study was aimed to understand the mechanism of fatty acid-mediated inflammation and look for an effective target which can prevent the inflammatory response induced by obesity. In this study, we used the saturated fatty acid palmitic acid (PA) to activate TLR4 signal pathway in human monocyte cells THP-1 that established an intracellular inflammatory model. Followed with activated TLR4, downstream molecular TRAF6 was upregulated and ultimately induced proinflammatory cytokine production. Based on this model, we also found that PA downregulated miR-194 expression with TLR4 activation. Moreover, our results showed that key signal molecular TRAF6 is a target of miR-194, overexpression of miR-194 directly decreased TRAF6 expression and attenuated the release of proinflammatory cytokine TNF-α in PA-activated monocyte THP-1. We conclude that miR-194 negatively regulates the TLR4 signal pathway which is activated by PA through directly negative TRAF6 expression.  相似文献   
92.
目的 检测肝泡型包虫病肝组织中miR-106b-25基因簇(miR-106b、miR-93、miR-25)的表达水平,分析3者在肝纤维化进程中的作用及其相互关系。方法 将20例经手术治疗的肝泡型包虫病肝组织匹配后分为病灶旁肝组织和正常肝组织,RT-PCR技术检测miR-106b-25基因簇的表达水平。HE和Masson染色观察病理变化与纤维化程度。结果 病灶旁肝组织纤维化程度高于正常肝组织;miR-106b-25基因簇在病灶旁肝组织的表达量均高于正常肝组织;miR-106b-25基因簇表达量与肝纤维化程度呈正相关;随着纤维化程度加重,miR-106b-25基因簇各成员的表达量也增加;3种miRNA之间表达呈正相关。结论 泡型包虫病病灶旁肝组织比正常肝组织纤维化程度严重,miR-106b-25基因簇参与肝泡型包虫病致肝纤维化。  相似文献   
93.
94.
目的探讨环状RNA PUM1(circPUM1)对结肠癌细胞增殖、凋亡、迁移、侵袭的影响及其分子机制。方法实时荧光定量聚合酶链反应(qRT-PCR)检测结肠癌组织、癌旁组织中circPUM1、微小RNA-524-5p(miR-524-5p)的表达量。体外培养人结肠癌细胞株SW620,分别将si-NC、si-circPUM1、miR-NC、miR-524-5p mimics、si-circPUM1与anti-miR-NC、si-circPUM1与anti-miR-524-5p转染至SW620细胞。甲基噻唑基四唑(MTT)检测细胞增殖;Transwell小室实验检测细胞迁移、侵袭能力;流式细胞术检测细胞凋亡率;双荧光素酶报告实验验证circPUM1是否能够结合miR-524-5p;蛋白免疫印迹法(Western blotting)检测细胞周期蛋白1(Cyclin D1)、p21、基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)、B淋巴细胞瘤-2(Bcl-2)、B淋巴细胞瘤-2相关蛋白(Bax)表达量。结果结肠癌组织circPUM1的表达水平显著高于癌旁组织(P<0.05),miR-524-5p的表达水平显著降低(P<0.05);干扰circPUM1表达或miR-524-5p过表达后,细胞活力显著降低(P<0.05),迁移细胞数与侵袭细胞数显著减少(P<0.05),细胞凋亡率显著升高(P<0.05),Cyclin D1、MMP-2、MMP-9、Bcl-2蛋白表达显著降低(P<0.05),p21、Bax蛋白表达显著升高(P<0.05);双荧光素酶报告实验证实circPUM1可靶向结合miR-524-5p的作用位点;抑制miR-524-5p表达可减弱干扰circPUM1表达对SW620细胞增殖、凋亡、迁移、侵袭的作用。结论circPUM1可通过海绵吸附miR-524-5p促进结肠癌细胞增殖、迁移、侵袭,抑制细胞凋亡。  相似文献   
95.
目的检测并分析结直肠癌组织和细胞系中miR-574-3p的表达情况及其对结直肠癌细胞发生、发展的影响。方法收集武汉市第三医院11对手术切除结直肠癌患者的癌组织和对应癌旁组织,3种结直肠癌细胞系和1种正常结直肠上皮细胞,通过实时荧光定量聚合酶链反应(qRT-PCR)检测临床样本及结直肠癌细胞系中miR-574-3p的表达水平;通过转染miR-574-3p mimic及相应对照mimic NC实现上调结直肠癌细胞(HCT-8、HCT-116)中miR-574-3p的表达水平,采用CCK-8、EdU、克隆形成实验、流式凋亡实验和流式细胞周期实验检测过表达miR-574-3p后对结直肠癌细胞的增殖、凋亡和细胞周期的影响。结果癌旁组织中miR-574-3p的表达差异倍数显著高于对应癌组织(P<0.05),在3种结直肠癌细胞系中miR-574-3p的表达较正常结肠上皮细胞也显著降低(P<0.05)。CCK-8、EdU、克隆形成实验表明,过表达miR-574-3p抑制结直肠癌细胞的增殖能力。流式凋亡实验结果显示,过表达miR-574-3p促进结直肠癌细胞的凋亡能力。流式细胞周期结果显示,过表达miR-574-3p使结直肠癌细胞发生G0/G1期阻滞。结论结直肠癌组织和细胞系中的miR-574-3p均低表达,上调结直肠癌细胞(HCT-8、HCT-116)中miR-574-3p可以抑制细胞增殖,促进凋亡并发生G0/G1期阻滞。  相似文献   
96.
微小RNA(microRNA,miRNA)是一大类短链非编码RNA,可以直接结合靶基因的3′非翻译区,进而影响基因表达,在心血管疾病中发挥关键作用。其中,microRNA-206(miR-206)是心脏发育和生理活动的关键调控因子,不仅可以作为诊断的标志分子,也可作为疾病治疗的定向作用点。本文综述了miR-206调节心肌细胞、内皮细胞、平滑肌细胞、自主神经细胞等细胞的基本功能,以及miR-206在冠状动脉疾病、心肌梗死、心力衰竭、心律失常、肺动脉高压等疾病发生发展中的具体作用和机制。  相似文献   
97.
BACKGROUNDPrevious studies have suggested that long non-coding RNAs (lncRNA) TP73-AS1 is significantly upregulated in several cancers. However, the biological role and clinical significance of TP73-AS1 in pancreatic cancer (PC) remain unclear. AIMTo investigate the role of TP73-AS1 in the growth and metastasis of PC.METHODSThe expression of lncRNA TP73-AS1, miR-128-3p, and GOLM1 in PC tissues and cells was detected by quantitative real-time polymerase chain reaction. The bioinformatics prediction software ENCORI was used to predict the putative binding sites of miR-128-3p. The regulatory roles of TP73-AS1 and miR-128-3p in cell proliferation, migration, and invasion abilities were verified by Cell Counting Kit-8, wound-healing, and transwell assays, as well as flow cytometry and Western blot analysis. The interactions among TP73-AS1, miR-128-3p, and GOLM1 were explored by bioinformatics prediction, luciferase assay, and Western blot. RESULTSThe expression of TP73-AS1 and miRNA-128-3p was dysregulated in PC tissues and cells. High TP73-AS1 expression was correlated with a poor prognosis. TP73-AS1 silencing inhibited PC cell proliferation, migration, and invasion in vitro as well as suppressed tumor growth in vivo. Mechanistically, TP73-AS1 was validated to promote PC progression through GOLM1 upregulation by competitively binding to miR-128-3p. CONCLUSIONOur results demonstrated that TP73-AS1 promotes PC progression by regulating the miR-128-3p/GOLM1 axis, which might provide a potential treatment strategy for patients with PC.  相似文献   
98.
 目的 探讨miR-214-5p通过靶向调控PTEN的表达对破骨分化和骨质疏松的影响。方法 选取2019-03至2020-05在空军军医大学唐都医院外科进行脊柱手术的骨质疏松患者20例(骨质疏松组),同时选取非骨质疏松症患者20例为对照组,抽取两组骨髓血。将miR-214-5pmimics(miR-214-5pmimics组)、miR-214-5p空质粒(miR-214-5pvector组)、shZFAS1载体(sh PTEN组)、shZFAS1空载体(sh vector组)转染到骨质疏松患者细胞,对照组细胞不进行任何转染处理。采用RT-qPCR 检测骨髓单个核细胞中的miR-214-5p和PTEN mRNA及 Raw264.7单核巨噬细胞中NFaTc1、MMP9、TRAP、CTSK的mRNA水平;通过TRAP染色检测TRAP染色的阳性率;通过Western blot 检测PTEN、NFATc1、AKT和PI3K蛋白水平。结果 骨质疏松组miR-214-5p水平的表达明显高于对照组(P<0.001),骨质疏松组PTEN的表达显著低于对照组(P=0.009);miR-214-5pmimics组中TRAP表达阳性率明显高于对照组和miR-214-5p vector组(P<0.001);sh PTEN组中TRAP表达阳性率明显高于对照组和sh vector组(P<0.001);miR-214-5p mimics组中的NFaTc1、MMP9、TRAP和CTSK水平显著高于对照组(P<0.001);sh PTEN组中的NFaTc1、MMP9、TRAP和CTSK水平显著高于对照组(P<0.001);与miR-214-5p mimics组相比,miR-214-5pmimics+PTEN组中TRAP表达阳性率显著降低(P<0.001)。结论 骨质疏松症患者的骨髓单个核细胞中miR-214-5p表达上调,miR-214-5p可以调控PTEN表达,过表达miR-214-5p可能通过靶向PTEN促进破骨细胞分化。  相似文献   
99.
On activation platelets release microRNAs and extracellular vesicles (EV) into circulation. The release of EV from platelets has been shown to be dependent on the agonist; in this study, we investigated whether the microRNA profile or EV released from platelets was also agonist specific.

Washed platelets from healthy subjects were maximally stimulated with agonists specific for the receptors for collagen (Glycoprotein VI (GPVI)), thrombin (PAR1/PAR4), or ADP (P2Y1/P2Y12) with/without inhibiting secondary mediators, using aspirin to block cyclooxygenase-1 and apyrase to remove ADP. The released microRNAs were profiled using TaqMan microRNA microarray cards. Platelet-derived EV (pdEV) were characterized by size (Nanoparticle Tracking Analysis, NTA), for procoagulant activity (Annexin-V binding and support of thrombin generation), and for the EV markers CD63 and HSP70.

Platelet activation triggered the release of 57–79 different microRNAs, dependent upon agonist, with a core of 46 microRNAs observed with all agonists. There was a high level of correlation between agonists (r2 > 0.98; p < 0.0001 for all), and with the microRNA content of the parent platelets (r2 > 0.98; p < 0.0001). The 46 microRNAs seen in all samples are predicted to have significant effects on the translation of proteins involved in endocytosis, cell cycle control, and differentiation. MiR-223-3p was the most abundant in all samples and has previously been implicated in myeloid lineage development and demonstrated to have anti-inflammatory effects. Stimulation through GPVI produced a pdEV population with significantly more procoagulant activity than the other agonists. Apyrase significantly reduced microRNA and pdEV release, while aspirin had little effect.

These data suggest that all tested agonists trigger the release of a similar microRNA profile while the procoagulant activity of the pdEV was agonist dependent. ADP was shown to play an important role in the release of both microRNAs and pdEV.  相似文献   

100.
Long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) is reported to be linked to inflammation and cell apoptosis. However its role in sepsis induced kidney injury remains unclear. This study aims to explore the possible mechanism of CRNDE in kidney injury induced by sepsis. In vivo urine-derived sepsis (US) rat model and in vitro LPS-induced HK-2 and HEK293 cells were established. Kidney function was measured in rats from different groups. Relative levels of tumor necrosis factor-α (TNF-α) and interleukin-1β(IL-1β) in kidney tissue were detected via Enzyme-linked immune sorbent assay (ELISA). Then we up- or down-regulated CRNDE and miRNA-181a-5p expression in the cells. The biological influence of CRNDE and miR-181a-5p on cells was studied using CCK-8 assay and Annexin V assay. Interaction between CRNDE and miR-181a-5p was determined by bioinformatics analysis, RT-PCR, and dual luciferase reporter assay. Peroxisome proliferator-activated receptor-α (PPARα) and cell apoptosis related molecules were detected by western blot. We demonstrated that CRNDE was markedly down-regulated while miR-181a-5p was significantly up-regulated in sepsis models. CRNDE interacted with miR-181a-5p, and negatively regulated its expression level. CRNDE knockdown in rats increased the urea nitrogen and serum creatinine in plasma. Knockdown of CRNDE or transfection of miR-181a-5p significantly inhibited proliferation and promoted apoptosis of HK-2 and HEK293 cells, while overexpression of CRNDE and transfection of miR-181a-5p inhibitors had opposite effects. For mechanism, miR-181a-5p directly targeted the 3′ untranslated region of PPARα, and depressed its protein level, and PPARα was regulated indirectly by CRNDE. We concluded that CRNDE protected renal cell from sepsis-induced injury via miR-181a-5p/PPARα pathway.  相似文献   
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