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991.
Lu Guimin Qiu ZhuxianP. O. Box School of Materials Science Metallurgy Norhteastern University Shenyang P. R. China 《中国有色金属学会会刊》1998,(1)
MEASUREMENTOFTHERMODYNAMICPROPERTIESOFLIQUIDAlMgALLOYS①LuGuiminandQiuZhuxianP.O.Box317,ScholofMaterialsScienceandMetalurgy,N... 相似文献
992.
Chen Xiaohong Liu Mai College of Business Management Central South University of Technology Changsha P. R. China Takahara Yasuhiko Department of Management Systems Engineering Chiba Institute of Technology Chiba Japan 《中国有色金属学会会刊》1998,(1)
FUZZYDECISIONMAKINGFORSELECTIONOFINFORMATIONSYSTEMDEVELOPMENTAPPROACH①ChenXiaohongandLiuMaiColegeofBusinesandManagement,Centr... 相似文献
993.
Cai Kefeng Nan Cewen Min Xinmin State Key Laboratory of Advanced Technology of Materials Compositing Wuhan University of Technology Wuhan P. R. China 《中国有色金属学会会刊》1998,(2)
MICROSTRUCTUREANDMECHANICALPROPERTIESOF(Nb,Ti)CNICKELBASESUPERALLOY①CaiKefeng,NanCewenandMinXinminStateKeyLaboratoryofAdvanc... 相似文献
994.
Hu Xiangzhao Kuang Lixin College of Resources Environment Civil Engineering Central South University of Technology Changsha P. R. China 《中国有色金属学会会刊》1998,(4)
SURVEYOFGEOLOGYLancangvolcanicbeltliesinthesouthwesternpartofYunnanProvince,P.R.Chinaandfromnorthtosouth,throughChanglin,Lan... 相似文献
995.
Matousková P Luxová A Matousková J Jiros P Svatos A Valterová I Pichová I 《Chembiochem : a European journal of chemical biology》2008,9(15):2534-2541
The knowledge of the molecular basis of communication in bumblebee communities is limited. None of the enzymes that participate in pheromone production have been characterized. Here, we cloned the gene encoding the Delta(9) desaturase from cDNA prepared from the total RNA of the pheromone gland and fat bodies of Bombus lucorum male. Functional expression of BlucNPVE desaturase in Saccharomyces cerevisiae and GC-MS analyses revealed its preference for C(18) saturated fatty acids. This suggests that Delta(9) desaturase is involved in the desaturation of metabolic fatty acids stored in triacylglyceroles (TAGs), because oleic acid is the most abundant fatty acid bound in TAG in B. lucorum and it is present in low concentration in the pheromone blend. The incubation of pheromone precursors with a dissected labial gland as well as direct injection of labelled pheromone substrates into B. lucorum males revealed that esterification of pheromone products occurs in the labial gland. These results support both the biosynthesis of pheromones from common lipids and the de novo synthesis of unsaturated pheromones in the labial gland. 相似文献
996.
Pettersson S Pérez-Nueno VI Ros-Blanco L Puig de La Bellacasa R Rabal MO Batllori X Clotet B Clotet-Codina I Armand-Ugón M Esté J Borrell JI Teixidó J 《ChemMedChem》2008,3(10):1549-1557
HIV cell fusion and entry have been validated as targets for therapeutic intervention against infection. Bicyclams were the first low-molecular-weight compounds to show specific interaction with CXCR4. The most potent bicyclam was AMD3100, in which the two cyclam moieties are tethered by a 1,4-phenylenebis(methylene) bridge. It was withdrawn from clinical trials owing to its lack of oral bioavailability and cardiotoxicity. We have designed a combinatorial library of non-cyclam polynitrogenated compounds by preserving the main features of AMD3100. At least two nitrogen atoms on each side of the p-phenylene moiety, one in the benzylic position and the other(s) in the heterocyclic system were maintained, and the distances between them were similar to the nitrogen atom distances in cyclam. A selection of diverse compounds from this library were prepared, and their in vitro activity was tested in cell cultures against HIV strains. This led to the identification of novel potent CXCR4 coreceptor inhibitors without cytotoxicity at the tested concentrations. 相似文献
997.
998.
Surrogate endpoints in oncology research and practice have garnered increasing attention over the past two decades. This activity has largely been driven by the promise surrogate endpoints appear to hold: the potential to get new therapies to seriously ill patients more rapidly. However, uncertainties abound. Even agreeing upon a definition of a "valid" surrogate endpoint has not been a straightforward exercise; this article begins by highlighting differences in how this term has been previously captured and applied, as well as laying out the basic criteria essential for its application in advanced colorectal cancer. Ideally, these elements include (but are not limited to) ease of measurement, rapid indication of treatment effect, and, most importantly, reliable and consistent prediction of the true impact of a treatment on the ultimate outcome of interest: overall survival. The strengths and weaknesses of current potential surrogate endpoints in advanced colorectal cancer, including performance status, carcinoembryonic antigen plasma level, overall response rate, time to progression, and disease-free survival, are each considered in turn. Finally, limitations of surrogate endpoints in the clinical setting, including challenges in extrapolation to new therapies, and the incomplete provision of information about potential adverse effects, are discussed. Work remains to be done between physicians and statisticians to bridge the gap between that which is statistically demonstrable and that which will be clinically useful.The term ;surrogate endpoint' was virtually unknown by most oncologists 15 years ago. A search in PubMed [http://www.ncbi.nlm.nih.gov] based on the words ;surrogate and cancer' shows that more than 2000 papers were published in medical journals in the last 20 years, with a dramatic increase of interest in the last five years. Interestingly, the same trend is observed when the words ;surrogate and heart' are entered into PubMed, suggesting that the issue of surrogate endpoints goes beyond the field of oncology, although the frequency of discussion varies (Figure 1; note different y-axis scales for oncology and cardiology).The goal of the present paper is to discuss the main issues surrounding surrogate endpoints from a clinician's point of view, using as an example surrogate endpoints of overall survival (OS) in advanced colorectal cancer (ACC). 相似文献
999.
Segawa T Kateb F Duma L Bodenhausen G Pelupessy P 《Chembiochem : a European journal of chemical biology》2008,9(4):537-542
Although labile protons that are exchanging rapidly with those of the solvent cannot be observed directly, their exchange rate constants can be determined by indirect detection of scalar-coupled neighboring nuclei. We have used heteronuclear NMR spectroscopy to measure the exchange rate constants of labile protons in the side chains of lysine and arginine residues in ubiquitin enriched in carbon-13 and nitrogen-15 at neutral pH. Exchange rate constants as fast as 40x10(3) s(-1) were thus measured. These results demonstrate that NMR spectroscopy is a powerful tool for the characterization of lysine NH3(+) and arginine NH groups in proteins at physiologically relevant pH values. 相似文献
1000.
Rennert R Neundorf I Jahnke HG Suchowerskyj P Dournaud P Robitzki A Beck-Sickinger AG 《ChemMedChem》2008,3(2):241-253
Now that the human genome has been decoded, the demand for novel therapeutic concepts, such as gene and stem cell therapy, is higher than ever before. Although new and better pharmaceutical agents are available, their efficient delivery to the intracellular site of action is still a serious challenge. A possible solution to this problem is the use of cell-penetrating peptides as delivery vectors, including derivatives of human calcitonin (hCT). The aim of this study was to synthesise novel branched hCT-derived peptides for the noncovalent delivery of nucleic acids. The uptake of the resulting oligocationic peptides into various cell lines as well as primary cells was monitored by fluorescence microscopy. To determine the appropriate peptide-plasmid charge ratios for efficient cell transfection, electromobility shift assays were carried out. Finally, flow cytometric and fluorescence microscopic studies of gene expression highlighted two novel hCT-derived peptides as highly effective in the delivery of noncovalently complexed plasmid DNA. Thus, the absence of cytotoxicity paired with highly efficient cell internalisation and transfection rates, in primary cells as well, make both peptides powerful candidates as drug delivery vectors, especially for plasmid DNA, for both in vivo and ex vivo therapeutic applications. 相似文献