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991.
Yun HJ Cho YH Moon Y Park YW Yoon HK Kim YJ Cho SH Lee YI Kang BS Kim WJ Park K Seo W 《Experimental & molecular medicine》2008,40(3):345-353
For cancer gene therapy, cancer-specific over- expression of a therapeutic gene is required to reduce side effects derived from expression of the gene in normal cells. To develop such an expression vector, we searched for genes over-expressed and/or specifically expressed in cancer cells using bioinformatics and have selected genes coding for protein regulator of cytokinesis 1 (PRC1) and ribonuclease reductase 2 (RRM2) as candidates. Their cancer-specific expressions were confirmed in both breast cancer cell lines and patient tissues. We compared each promoter's cancer-specific activity in the breast normal and cancer cell lines using the luciferase gene as a reporter and confirmed cancer-specific expression of both PRC1 and RRM2 promoters. To test activities of these promoters in viral vectors, the promoters were also cloned into an adeno-associated viral (AAV) vector containing green fluorescence protein (GFP) as the reporter. The GFP expression levels by these promoters were various depending on cell lines tested and, in MDA-MB-231 cells, GFP activities derived from the PRC1 and RRM2 promoters were as strong as that from the cytomegalovirus (CMV) promoter. Our result showed that a vector containing the PRC1 or RRM2 promoter could be used for breast cancer specific overexpression in gene therapy. 相似文献
992.
Gombojav B Park H Kim JI Ju YS Sung J Cho SI Lee MK Ohrr H Radnaabazar J Seo JS 《Experimental & molecular medicine》2008,40(5):558-564
Elevated heart rate has been proposed as an independent risk factor for cardiovascular diseases, but their interrelationships are not well understood. In this study, we performed a genome-wide linkage scan in 1,026 individuals (mean age 30.6 years, 54.5% women) from 73 extended families of Mongolia and determined quantitative trait loci that influence heart rate. The DNA samples were genotyped using deCODE 1,039 microsatellite markers for 3 cM density genome-wide linkage scan. Correlation analysis was carried out to evaluate the correlation of the covariates and the heart rate. T-tests of the heart rate were also performed on sex, smoking and alcohol intake. Consequently, this model was used in a nonparametric genome-wide linkage analysis using variance component model to create a multipoint logarithm of odds (LOD) score and a corresponding P value. In the adjusted model, the heritability of heart rate was estimated as 0.32 (P<.0001) and a maximum multipoint LOD score of 2.03 was observed in 77 cM region at chromosome 18. The second largest LOD score of 1.52 was seen on chromosome 5 at 216 cM. Genes located on the specified locations in chromosomes 5 and 18 may be involved in the regulation of heart rate. 相似文献
993.
Xiao SH Reagan JD Lee PH Fu A Schwandner R Zhao X Knop J Beckmann H Young SW 《Combinatorial chemistry & high throughput screening》2008,11(3):195-215
GPCRs had significant representation in the drug discovery portfolios of most major commercial drug discovery organizations for many years. This is due in part to the diverse biological roles mediated by GPCRs as a class, as well as the empirical discovery that they have proven relatively tractable to the development of small molecule therapeutics. Publication of the human genome sequence in 2001 confirmed GPCRs as the largest single gene superfamily with more than 700 members, furthering the already strong appeal of addressing this target class using efficient and highly parallelized platform approaches. The GPCR research platform implemented at Amgen is used as a case study to review the evolution and implementation of available assays and technologies applicable to GPCR drug discovery. The strengths, weaknesses, and applications of assay technologies applicable to G alpha s, G alpha i and G alpha q-coupled receptors are described and their relative merits evaluated. Particular consideration is made of the role and practice of "de-orphaning" and signaling pathway characterization as a pre-requisite to establishing effective screens. In silico and in vitro methodology developed for rapid, parallel high throughput hit characterization and prioritization is also discussed extensively. 相似文献
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Choi HC Lee S Lee KK Noda I Park C Kwon CH Jung YM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,69(4):1110-1113
A promising possibility for the quantitative analysis of X-ray absorption near edge structure (XANES) spectra of nanosized electrode materials is demonstrated. We used a 2D map representation technique, which utilizes the values of the first derivatives of the absorbance with respect to the inserted Li(+) content plotted over the two-dimensional space defined by the inserted Li(+) content (mole) versus photon energy (eV) as a single map. The technique was applied to XANES spectra of the Li(y)CoO system in the first Li(+) insertion reaction for determining the structural and electronic variations associated with the change in Li(+) content. The obtained show that the intensities of two peaks at 7725 and 7711 eV increased with the Li(+) content and the difference of intensity change of these two peaks carried out for successive couples of spectra yielded the largest changes at 1.05 and 1.98 mol of Li content. This approach for quantitative analysis of XANES without using conventional simulation techniques enable us to interpret X-ray absorption spectroscopy (XAS) as a quantitative analytical technique with greater confidence. 相似文献
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Inokuma Y Easwaramoorthi S Jang SY Kim KS Kim D Osuka A 《Angewandte Chemie (International ed. in English)》2008,47(26):4840-4843
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