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31.
目的:研究组蛋白去乙酰化酶抑制剂曲古抑菌素A(trichostatinA,TSA)对前列腺癌细胞的抑制作用机理。方法:四甲基偶唑氮蓝(MTT)检测药物对肿瘤细胞增殖的影响;Hochest33342染色观察细胞凋亡的形态学变化;Western印迹分析雄激素受体(AR)蛋白的表达;反转录PCR检测AR转录水平的变化。结果:TSA在较低浓度即能有效抑制LNCaP细胞的增殖,EC50为125.9nmol·L-1,并诱导肿瘤细胞凋亡;药物处理后细胞周期依赖性蛋白激酶抑制剂p21表达增高,AR呈时间及剂量依赖性被清除。TSA对AR的清除是发生在蛋白水平的降解,而不影响其转录。结论:TSA能够清除对细胞生长具有重要作用的AR细胞信号通路,从而对前列腺癌LNCaP细胞发挥抑制作用。 相似文献
32.
Activation of mouse microglial cells affects P2 receptor signaling 总被引:11,自引:0,他引:11
Microglial cells are the immunocompetent cells of the CNS, which are known to exist in several activation states. Here we investigated the impact of microglial activation on the P2 receptor-mediated intracellular calcium ([Ca(2+)](i)) signaling by means of fluo-3 based Ca(2+)-imaging. Cultured mouse microglial cells were treated with either astrocyte-conditioned medium to induce a ramified morphology or LPS to shift the cells toward the fully activated stage. The extracellular application of ATP (100 microM) induced a [Ca(2+)](i) elevation in 85% of both untreated and ramified microglial cells, whereas only 50% of the LPS-activated cells responded to the stimulus. To characterise the pharmacological profile of microglial P2 receptors we investigated the effects of various P2 agonists on [Ca(2+)](i) in cultured microglial cells. Untreated and ramified microglial cells demonstrated a very similar sensitivity to the different P2 agonists. In contrast, in LPS-activated microglia, a sharp decrease of responses to P2 agonist stimulation was seen. This indicates that microglial activation influences the capability of microglial cells to generate [Ca(2+)](i) signals upon P2 receptor activation. 相似文献
33.
It has previously been reported that propofol regulates the development of human osteosarcoma (OS). However, the specific molecular mechanisms underlying the effect of propofol on OS remain poorly understood. Therefore, the aim of the present study was to explore the effects of propofol on OS U2OS cells and the potential underlying mechanism. The Cell Counting Kit-8 and colony formation assays were performed to assess cell viability and proliferation. Furthermore, cell apoptosis was assessed using the TUNEL assay and western blotting. Wound healing and Transwell assays were performed to evaluate OS cell migration and invasion abilities, respectively. The protein expression levels of epithelial-mesenchymal transition (EMT)-, autophagy- and adenosine monophosphate-activated protein kinase (AMPK)/FOXO1 signaling pathway-related proteins were also determined using western blotting. The results demonstrated that propofol significantly reduced the viability of OS cells and promoted autophagy in a dose-dependent manner. Moreover, cell treatment with propofol significantly enhanced the protein expression levels of phosphorylated (p)-AMPK and FOXO1, while decreasing the protein levels of p-FOXO1. Furthermore, treatment with propofol significantly suppressed cell viability, migration and invasion abilities and the EMT of OS cells, and potentially promoted cell apoptosis via inducing autophagy via the AMPK/FOXO1 signaling pathway. In summary, the present study indicated that propofol potentially had an inhibitory effect on the development of OS cells via AMPK/FOXO1-mediated autophagy. These results have therefore provided an experimental basis for further studies into the therapeutic effect of propofol on OS. 相似文献
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Adenoviruses can cause infections in people of all ages at all seasons of the year. Adenovirus infections cause mild to severe illnesses. Children, immunocompromised patients, or those with existing respiratory or cardiac disease are at higher risk. Unfortunately, there are no commercial drugs or vaccines available on the market for adenovirus infections. Therefore, there is an urgent need to discover new antiviral drugs or drug targets for adenovirus infections. To identify potential antiviral agents for adenovirus infections, we screened a drug library containing 2138 compounds, most of which are drugs with known targets and past phase I clinical trials. On a cell-based assay, we identified 131 hits that inhibit adenoviruses type 3 and 5. A secondary screen confirmed the antiviral effects of 59 inhibitors that inhibit the replication of adenoviruses type 3 or 5. Most of the inhibitors target heat shock protein, protein tyrosine kinase, the mTOR signaling pathway, and other host factors, suggesting that these host factors may be essential for replicating adenoviruses. Through this study, the newly identified adenovirus inhibitors may provide a start point for developing new antiviral drugs to treat adenovirus infections. Further validation of the identified drug targets can help the development of new therapeutics against adenovirus infections. 相似文献
38.
目的 观察自发性高血压大鼠(SHR)血清脂联素浓度及脂联素受体在大鼠心脏组织的分布,并观察脂联素对血管紧张素Ⅱ(AngⅡ)诱导的心肌成纤维细胞(CFbs)Ⅰ型胶原合成的影响,以评价脂联素在高血压心肌纤维化中的作用。方法 酶联免疫吸附实验法(ELISA)检测大鼠血清脂联素浓度;实时定量PCR法检测大鼠心脏脂联素受体;消化法培养CFbs;蛋白免疫印迹(Western Blot)检测Ⅰ型胶原蛋白。结果SHR血清脂联素浓度及其受体在心脏的分布随周龄增加而降低,脂联素能部分抑制AngⅡ诱导的CFbsⅠ型胶原的合成。结论 血清脂联素浓度与高血压发生发展有关,脂联素能部分抑制心肌纤维化。 相似文献
39.
通过观察虎杖苷对宫颈癌HeLa细胞体外生长的抑制作用,初步探讨其诱导凋亡的可能机制。不同浓度的虎杖苷(50,100,150μmol·L~(-1))处理HeLa细胞后,采用MTT法检测虎杖苷对HeLa细胞增殖的抑制作用,AO/EB染色法荧光显微镜观察HeLa细胞凋亡的形态学变化;Annexin/PI双标记法检测HeLa细胞凋亡率;流式细胞仪分析HeLa细胞周期分布;RTPCR和Western blot法检测HeLa细胞中PI3K,AKT,mTOR,P70S6K的mRNA和蛋白表达。结果显示,虎杖苷显著抑制HeLa细胞增殖,且具有一定剂量依赖性;虎杖苷能够引起HeLa细胞发生S期阻滞,促进细胞凋亡,显著下调HeLa细胞中PI3K,AKT,mTOR,P70S6K的mRNA和蛋白表达。表明虎杖苷具有抑制宫颈癌HeLa细胞增殖及诱导凋亡的作用,其机制可能与抑制PI3K/AKT/mTOR信号通路及其下游基因蛋白表达有关。 相似文献
40.
目的:研究抗纤灵方对PI3K/AKT/mTOR信号通路的影响及抗肾纤维化作用机制。方法:将60只C57小鼠,随机分为假手术组10只和手术组50只,手术组行5/6肾切除术。术后2周,手术组随机分为模型组、抗纤灵低、中、高剂量组及雷帕霉素阳性药组,各组10只。假手术组给予0.5 mL生理盐水ig,抗纤灵方低、中、高剂量组分别给予0.5 mL抗纤灵药物ig(0.1,0.2,0.4 mg·kg-1),阳性药组给予0.5 mL雷帕霉素ig(0.016μg·kg-1),ig 12周后处死小鼠,在处死小鼠前1 d收集24 h尿液检测24 h蛋白定量,眼眶采血测血肌酐、尿素氮,取残肾采用HE观察肾脏组织形态改变,PCR法检测肾组织中PI3K/AKT/mTOR mRNA表达。结果:与假手术组比较,模型组24 h尿蛋白定量,血肌酐,尿素氮,PI3K/AKT/mTOR mRNA表达均显著升高(P0.01),肾脏病理形态改变明显;与模型组比较,各治疗组24 h尿蛋白定量,血肌酐,尿素氮,PI3K/AKT/mTOR mRNA表达均下降(P0.05),肾脏组织学形态改善。结论:抗纤灵方能降低小鼠24 h尿蛋白定量,改善肾功能,延缓肾纤维化发生;其机制可能与抑制PI3K/AKT/mTOR信号通路表达相关。 相似文献