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141.
仁术健胃颗粒逆转胃癌前期病变的临床研究   总被引:11,自引:1,他引:10  
目的观察仁术健胃颗粒对胃癌前病变的逆转作用。方法将120例符合诊断标准的胃癌前期病变患者,随机分为仁术健胃颗粒治疗组80例和胃复春对照组40例进行临床疗效观察。结果①综合疗效:治疗组总有效率为91.25%,对照组为75.00%,经统计学处理,差异有显著性(P〈0.05);②治疗组胃镜及对萎缩、肠化、异型增生的疗效分别为71.25%、77.50%、79.49%、88.46%,对照组为52.50%、6  相似文献   
142.
本文总结分析了 1995年 8月~ 1996年 7月在我院出生的 15 3例正常新生儿血清总胆红素水平。根据本组结果和全国黄疸调查协作组对血清胆红素 >12 .9mg/dl的新生儿作脑干听力诱发电位无异常发现 ,提示正常新生儿高胆红素血症的诊断标准应作适当调整 ,而高胆红素干预标准亦应相应提高  相似文献   
143.
目的 比较不同参比点豚鼠体表的心电图。方法 取30只成年豚鼠,分别以中心电端和右前额为参比点,同步记录豚鼠第1、4、7肋间隙环胸3圈18个点的心电图。比较相同测试点中不同的参比点的两组心电图R(r)波振幅。结果 以右前额为参比点记录的心电图R(r)波振幅比以中心电端为参比点的心电图R(r)波振幅大,具显著性差异(P<0.05)。结论 右前额作为记录心电图的参比点要比中心电端优越。  相似文献   
144.
电化法研究壳聚糖树脂与游离酸的相互作用   总被引:1,自引:0,他引:1  
利用电化学实验技术跟踪交联壳聚糖树脂吸附低浓度游离酸的行为,讨论了不同盐酸浓度和不同甲醇浓度两种因素对吸附的影响,并利用固液相互作用方程,求取吸附剂-吸附质相互作用能。实验结果表明,交联壳聚糖树脂吸附低浓度游离酸的过程是遵循单分子 机制进行的。  相似文献   
145.
CD7 and CD57 are related to the differentiation and functional stages of CD8+ T cells. However, the role of their combined presence in CD8+ T cells in patients with chronic hepatitis B virus (HBV) infection, especially those with end-stage liver disease, remains unclear. Blood samples from healthy volunteers and patients with chronic hepatitis B were analyzed via Luminex assay and ELISA to measure plasma cytokine levels. Further, recombinant IL-22 was used to stimulate peripheral blood mononuclear cells from healthy volunteers, and the frequency of CD3+CD4CD7+CD57 T cells and apoptosis rates were investigated via flow cytometry. Patients with end-stage liver disease, particularly those with acute to chronic liver failure, showed decreased CD3+CD4CD7+CD57 T cell frequency. Furthermore, the prevalence of CD3+CD4CD7+CD57 T cells was negatively correlated with disease severity, prognosis, and complications (ascites). We also observed that IL-22 promoted apoptosis and brought about a decrease in the number of CD3+CD4CD7+CD57 T cells in a dose-dependent manner. CD3+CD4CD7+CD57 T cells displayed a B and T lymphocyte attenuator (BTLA)highCD25highCD127high immunosuppressive phenotype and showed low interferon-γ, tumor necrosis factor-α, granzyme A, and perforin expression levels. The present findings will elucidate the pathogenesis of HBV-related end-stage liver disease and aid the identification of novel drug targets.  相似文献   
146.
  1. The sigma-drug binding site of guinea-pig liver is carried by a protein which shares significant amino acid sequence similarities with the yeast sterol C8–C7 isomerase (ERG2 protein). Pharmacologically - but not structurally - the sigma1-site is also related to the emopamil binding protein, the mammalian sterol C8–C7 isomerase. We therefore investigated if sterol C8–C7 isomerase inhibitors are high affinity ligands for the (+)-[3H]-pentazocine labelled sigma1-binding site.
  2. Among the compounds which bound with high affinity to native hepatic and cerebral as well as to yeast expressed sigma1-binding sites were the agricultural fungicide fenpropimorph (Ki 0.005 nM), the antihypocholesterinaemic drugs triparanol (Ki 7.0 nM), AY-9944 (Ki 0.46 nM) and MDL28,815 (Ki 0.16 nM), the enantiomers of the ovulation inducer clomiphene (Ki 5.5 and 12 nM, respectively) and the antioestrogene tamoxifen (Ki 26 nM).
  3. Except for tamoxifen these affinities are essentially identical with those for the [3H]-ifenprodil labelled sterol C8–C7 isomerase of S. cerevisiae. This demonstrates that sigma1-binding protein and yeast isomerase are not only structurally but also pharmacologically related. Because of its affiliations with yeast and mammalian sterol isomerases we propose that the sigma1-binding site is localized on a sterol isomerase related protein, involved in postsqualene sterol biosynthesis.
  相似文献   
147.
  1. 8-Iso prostaglandin F (8-iso PGF) is one of a series of prostanoids formed independently of the cyclo-oxygenase pathway. It has been shown to be upregulated in many conditions of oxidant stress where its formation is induced by free radical-catalysed actions on arachidonic acid. As 8-iso PGF is formed in vivo in diseases in which oxidant stress is high such as septic shock, we have assessed the relative potency and efficacy of this compound in pulmonary arteries from control and lipopolysaccharide (LPS)-treated rats.
  2. Several studies have characterized the contractile actions of 8-iso PGF on various smooth muscle preparations, but its potential dilator actions have not been addressed. Thus these studies examined both the contractile and dilator actions of 8-iso PGF in rat pulmonary artery rings. The thromboxane mimetic U46619, PGE2 sodium nitroprusside (SNP) and acetyl choline (ACh) were used for comparison. Each prostanoid had to be dissolved in ethanol to a maximum concentration of 1×10−2M. At high concentrations, ethanol directly contracted pulmonary vessels. We were therefore limited by the actions of the vehicle such that we were unable to add prostanoids at concentrations higher than 1×10−4M. In some cases this meant that maximum responses were not achieved and in these cases the Emax and pD2 values are apparent estimates.
  3. The following rank order of potency was obtained from contractile studies; U46619>8-iso PGF>PGE2, each prostanoid producing concentration-dependent contractions (10−103×10−4M, 10−910−4M, 10−810−4M, respectively). As has been shown previously for other smooth muscle preparations, the thromboxane receptor (TP) antagonist ICI 192605, (1×10−6, 1×10−5 and 1×10−4M), inhibited the contractions of 8-iso PGF in a concentration-dependent fashion.
  4. The nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME; 1×10−4M), enhanced the contractile function of both 8-iso PGF and PGE2, but had no effect on that caused by U46619. Similarly, L-NAME inhibited the dilator function of all agents tested except the exogenous nitric oxide (NO) donor SNP, indicating that PGE2 and 8-iso PGF like ACh, act through the release of NO. The specificity of the effects of L-NAME were confirmed in studies with the inactive enantiomer D-NAME (1×10−4M), which did not affect the contractile or the dilator actions of 8-iso PGF. Furthermore, ICI 192605 enhanced the dilator actions of 8-iso PGF, suggesting that the dilator component of 8-iso PGF was achieved via activation of a non-TP receptor.
  5. Isoprostanes may modulate vascular tone by a direct action on TP receptors to cause contraction and via a distinct receptor leading to the release of NO to cause dilatation.
  相似文献   
148.
  1. 8-epi-prostaglandin (PG) F, a major F2 isoprostane, is produced in vivo by free radical-dependent peroxidation of lipid-esterified arachidonic acid. Both cyclo-oxygenase isoforms (COX-1 and COX-2) may also form free 8-epi-PGF as a minor product. It has been recently seen in human volunteers that the overall basal formation of 8-epi-PGF in vivo is mostly COX-independent and urinary 8-epi-PGF is therefore an accurate marker of ‘basal'' oxidative stress in vivo.
  2. To test the validity of this marker in the rat, we evaluated in vivo the effect of COX inhibition on the formation of 8-epi-PGF vs prostanoids. Two structurally unrelated COX inhibitors (naproxen: 30 mg kg−1 day−1; indomethacin: 4 mg kg−1 day−1) were given i.p. to rats kept in metabolic cages. In vivo formation of 8-epi-PGF was assessed by measuring its urinary excretion. Prostanoid biosynthesis was assessed by measuring urinary excretion of major metabolites of thromboxane (TX) and prostacyclin (2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF). All compounds were selectively measured by immunopurification/gas chromatography-mass spectrometry.
  3. Naproxen reduced urinary excretion of 2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF but, unexpectedly, also that of 8-epi-PGF (82, 49 and 52% inhibition, respectively). Indomethacin had a similar effect (77, 69 and 55% inhibition). Esterified 8-epi-PGF in liver and plasma remained unchanged after indomethacin.
  4. These findings prompted us to re-assess the contribution of COX activity to the systemic production of 8-epi-PGF in man. We gave naproxen (1 g day−1) to healthy subjects (four nonsmokers and four smokers). Urinary 8-epi-PGF remained unchanged in the two groups (9.63±0.99 before vs 10.24±1.01 after and 20.14±3.00 vs 19.03±2.45 ng h−1 1.73 m−2), whereas there was a marked reduction of major urinary metabolites of thromboxane and prostacyclin (about 90% for both 11-dehydro-TXB2 and 2,3-dinor-TXB2; >50% for 2,3-dinor-6-keto-PGF).
  5. To investigate whether rat COX-1 produces 8-epi-PGF more efficiently than human COX-1, we measured the ex vivo formation of 8-epi-PGF and TXB2 simultaneously in whole clotting blood. Serum levels of 8-epi-PGF and TXB2 were similar in rats and man.
  6. We conclude that a significant amount of COX-dependent 8-epi-PGF is present in rat but not in human urine under normal conditions. This implies that urinary 8-epi-PGF cannot be used as an index of near-basal oxidant stress in rats. On the other hand, our data further confirm the validity of this marker in man.
  相似文献   
149.
150.
  1. The production of chemokines by vascular smooth muscle cells (SMC) is implicated in the pathogenesis of atherosclerosis, although the factors regulating chemokine production by these cells are incompletely characterized.
  2. We describe the differential stimulation of interleukin-(IL)-8, monocyte chemoattractant protein (MCP)-1 and regulated on activation normal T-cell expressed and secreted (RANTES) synthesis following treatment of human vascular SMC with IL-1α or tumour necrosis factor α (TNFα). Under basal conditions, cultured SMC release very low amounts of IL-8, MCP-1 and RANTES as assessed by specific ELISA. Concentration-response studies with IL-1α or TNFα revealed that each stimulus induced a similar amount of MCP-1. In contrast approximately three fold more IL-8 was induced by IL-1α than by TNFα whereas significant RANTES production was induced only by TNFα. These findings point to a divergence in the regulation of synthesis of the different chemokines in response to IL-1α or TNFα stimulation.
  3. The T-cell derived cytokines IL-10 and IL-13 were also found to have differential effects on chemokine production by SMC. IL-13, but not IL-10, significantly enhanced IL-8 and MCP-1 release in response to IL-1α or TNFα. This increase in chemokine release appeared to be accounted for by increased mRNA expression.
  4. These findings provide support for the concept that smooth muscle cells can have an active role in a local immune response via the production of chemokines which can be selectively modulated by T-cell derived cytokines.
  相似文献   
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