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51.
Turkish twin brothers affected with hereditary sensory and autonomic neuropathy type IV (HSAN IV) are reported. Their clinical findings were generally typical for HSAN IV. Interestingly they both had preserved periodontal sensation. Mutation analysis of the NTRK1 gene showed a homozygous c.2001C>T substitution in exon 15 in both twins. This base substitution is predicted to change a polar, positively charged amino acid arginine to the highly active amino acid cystein at position 654 (p.Arg654Cys). The parents were heterozygous for the mutation. This mutation has been reported previously in one Japanese and one Arab patients. The preserved periodontal sensation has not previously been reported in patients affected with HSAN IV. This preserved sensation in our patients might have been through Ruffini endings, the periodontal mechanoreceptors which have been reported to be present in TrkA knockout mice. Here we report the first twins affected with HSAN IV and the observation that periodontal sensation is not affected by mutation in NTRK1.  相似文献   
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BackgroundClass-related boredom experienced by nursing students during theoretical lessons may affect their health and learning outcomes. Perceived teacher enthusiasm of nursing students may dampen their boredom, but little empirical research has investigated their relationship.ObjectivesThe aim of the current study is to investigate the dampening effects of nursing students' perceived teacher enthusiasm on their class-related boredom during theoretical lessons. The main theoretical framework is control-value theory of achievement emotions.DesignA cross-sectional survey was used.Methods352 nursing students during their theoretical lessons completed questionnaires on perceived teacher enthusiasm, boredom proneness, perceived task difficulty and class-related boredom. Correlation and classic multiple hierarchical analysis results supported the hypothesis about the relationships among variables.ResultsAfter controlling the effects of demographic variables, boredom proneness and perceived task difficulty, perceived teacher enthusiasm negatively predicted class-related boredom significantly.ConclusionPerceived teacher enthusiasm of nursing students can predict their class-related boredom significantly.  相似文献   
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A new semi-empirical formula for the calculation of the (n, He-3) cross section at 14.6 MeV neutron energy is obtained. It is based on the evaporation model. The new formula with three parameters is found to give a better fit to the data than the previous comparable formulae.  相似文献   
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【目的】 通过统计分析“中国科技期刊登峰行动计划”入选期刊的发展现状,为优化资助机制、培育世界一流科技期刊提供参考。【方法】 基于Web of Science的JCR评价数据,运用文献计量法和深度访谈法对入选期刊发展现状和存在问题进行分析并提出建议。【结果】 入选期刊影响因子总体提升不明显,存在片面追求影响因子的倾向;资助的“解渴”“解困”作用明显,但由于期刊国际化办刊思路不清晰,谋划不足,撬动期刊实现世界一流建设目标的杠杆作用发挥得并不充分。【结论】 资助方应通过注重资助效果评估和反馈,清晰资助导向,促进资助效果形成良性循环。期刊方应深入理解“世界一流科技期刊”的建设内涵,把握规律,探索模式,积极进行国际化办刊实践,提升期刊国际影响力。  相似文献   
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The aim of this study was to evaluate the role of diffusion kurtosis imaging (DKI) in the characterization of clear cell renal cell carcinoma (ccRCC) and to correlate DKI parameters with tumor cellularity. Fifty‐nine patients with pathologically diagnosed ccRCCs were evaluated by DKI on a 3‐T scanner. Regions of interest were drawn on the maps of the mean diffusion coefficient (MD) and mean diffusion kurtosis (MK). All ccRCCs were histologically graded according to the Fuhrman classification system. Tumor cellularity was measured by the nuclear‐to‐cytoplasm (N/C) ratio and the number of tumor cell nuclei (NTCN). ccRCCs were classified as grade 1 (n = 23), grade 2 (n = 24), grade 3 (n = 10) and grade 4 (n = 3). Both MD and MK could readily discriminate between normal renal parenchyma and ccRCCs (p < 0.001), and receiver operating characteristic (ROC) curve analysis showed that MK exhibited a better performance with an area under the ROC curve of 0.874 and sensitivity/specificity of 68.33%/100% (p < 0.001). Further, MD and MK were significantly different between grade 1 and grades 3 and 4 (p = 0.01, p < 0.001) and between grade 2 and grades 3 and 4 (p = 0.015, p < 0.005), respectively. However, no significant difference was found between grade 1 and grade 2 (p > 0.05) for both MD and MK. With regard to NTCN, no significant difference was found between any two grades (p > 0.05), and the N/C ratio changed significantly with grade (p < 0.01, between any two grades). Negative correlations were found between MK and MD (r = –0.56, p < 0.001), and between MD and N/C ratio (r = –0.36, p < 0.005), whereas MK and the N/C ratio were positively correlated (r = 0.45, p = 0.003). DKI could quantitatively characterize ccRCC with different grades by probing non‐Gaussian diffusion properties related to changes in the tumor microenvironment or tissue complexities in the tumor. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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A method was proposed for determination mass absorption coefficient of gamma rays for compounds, alloys and mixtures. It is based on simulating interaction processes of gamma rays with target elements having atomic numbers from Z=1 to Z=92 using the MCSHAPE software. Intensities of Compton scattered gamma rays at saturation thicknesses and at a scattering angle of 90° were calculated for incident gamma rays of different energies. The obtained results showed that the intensity of Compton scattered gamma rays at saturations and mass absorption coefficients can be described by mathematical formulas. These were used to determine mass absorption coefficients for compound, alloys and mixtures with the knowledge of their Compton scattered intensities. The method was tested by calculating mass absorption coefficients for some compounds, alloys and mixtures. There is a good agreement between obtained results and calculated ones using WinXom software. The advantages and limitations of the method were discussed.  相似文献   
59.
A maternity testing case is reported, in which the child showed tri-allelic patterns in two short tandem repeat (STR) loci. The genotypes of Penta D of the mother and the child were 9,13 and 9,10,13, respectively. Those of D21S11 were 32.2,35 and 29,35, respectively, but intensity ratio of alleles 29 and 35 of the child was 1:2. These results suggested the copy number variations (CNVs) or trisomy of chromosome 21. By further examination using STR-based chromosome aneuploidy detection kit, three alleles were detected in D21S1411, LFG21 and Penta D, and 2 alleles with intensity ratio of 1:2 were observed in D21S2502, D21S1435, D21S11 and D21S1246. Karyotype and whole-genome SNP array analyses showed that the child had a free trisomy 21. In addition, partially homologous non-sister chromatid crossover occurred at the region 19181770-39499178 on the long arm of chromosome 21.  相似文献   
60.
Neuronal glycoprotein M6a belongs to the tetraspan proteolipid protein (PLP) family. Mutations in GPM6A gene have been related to mental disorders like schizophrenia, bipolar disorders and claustrophobia. M6a is expressed mainly in neuronal cells of the central nervous system and it has been extensively related to neuronal plasticity. M6a induces neuritogenesis and axon/filopodium outgrowth; however its mechanism of action is still unresolved. We recently reported that the integrity of the transmembrane domains (TMDs) 2 and 4 are critical for M6a filopodia induction. There is also experimental data suggesting that M6a might be involved in synaptogenesis. In this regard, we have previously determined that M6a is involved in filopodia motility, a process that is described in the first step of the filopodial model for synaptogenesis. In this work we analyzed the possible involvement of M6a in synaptogenesis and spinogenesis, and evaluated the effect of two non-synonymous SNPs present in the coding region of TMD2-GPM6A in these processes. The results showed that endogenous M6a colocalized with both, pre-synaptic (synaptophysin) and post-synaptic (NMDA-R1), markers along of neuronal soma and dendrites. M6a-overexpressing neurons displayed an increased number of synaptophysin and NMDA-R1 puncta and, also, an increased number of colocalization puncta between both markers. Conversely, the number of synaptic puncta markers in neurons expressing nsSNP variants was similar to those of control neurons. Overexpression of M6a is accompanied by an increase in spine density, particularly in mature spines, as compared with neurons expressing mGFP or GPM6A nsSNP variants. Taken together, these results suggest that M6a contributes positively to spine and, likely, synapse formation.  相似文献   
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