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91.
We describe herein some of our initial studies in pursuit of a simple, economical method of mass producing electrochromic displays. The approach we have taken is to print the display on polymer film utilizing commercially available conductive inks in an interdigitated electrode structure with a conductive metal oxide powder, dispersed in a polymer binder, as the electrode surface. A range of electrochromic materials suitable for use with an aqueous gel electrolyte have been explored and examples presented.  相似文献   
92.
Substandard, falsified, and counterfeit medications are a concern for the industry and for the public’s health. Data collection and research on these illegitimate drugs must continue to be a priority and common recommendations must be implemented immediately. The health of the public continues to be at risk, and as such global consensus and collaboration must be swift. Process improvements and policy decisions can support expert recommendations while technology and research continue to drive home change. Addressing counterfeit and substandard drugs is cost effective, feasible, and the right thing to do.  相似文献   
93.
Dark-capacitance transients in MIS tunnel diodes switched from accumulation to deep depletion depend on the interface state occupancy. This time dependent function is derived and its behavior described for electron emission and electron-hole pair generation with tunneling and thermally controlled occupancies. A new method of determining the tunneling relaxation time constant τT from the electron emission transient at low temperature is described. Measurements of MIS tunnel diodes with oxide thickness dox = 17 to 80 Å agree with theory and the resultant values of τT compare with previously reported results from photocapacitance[2].  相似文献   
94.
Apolipoprotein E (ApoE) is a multifunctional protein expressed in several tissues, including those of the liver. This lipoprotein component is responsible for maintaining lipid content homeostasis at the plasma and tissue levels by transporting lipids between the liver and peripheral tissues. The ability of ApoE to interact with host-cell surface receptors and its involvement in several cellular pathways raised questions about the hijacking of ApoE by hepatotropic viruses. Hepatitis C virus (HCV) was the first hepatitis virus reported to be dependent on ApoE for the completion of its lifecycle, with ApoE being part of the viral particle, mediating its entry into host cells and contributing to viral morphogenesis. Recent studies of the hepatitis B virus (HBV) lifecycle have revealed that this virus and its subviral envelope particles also incorporate ApoE. ApoE favors HBV entry and is crucial for the morphogenesis of infectious particles, through its interaction with HBV envelope glycoproteins. This review summarizes the data highlighting the crucial role of ApoE in the lifecycles of HBV and HCV and discusses its potential role in the lifecycle of other hepatotropic viruses.  相似文献   
95.
Visual deficit is one of the complications of Huntington disease (HD), a fatal neurological disorder caused by CAG trinucleotide expansions in the Huntingtin gene, leading to the production of mutant Huntingtin (mHTT) protein. Transgenic HD R6/1 mice expressing human HTT exon1 with 115 CAG repeats recapitulate major features of the human pathology and exhibit a degeneration of the retina. Our aim was to gain insight into the ultrastructure of the pathological HD R6/1 retina by electron microscopy (EM). We show that the HD R6/1 retina is enriched with unusual organelles myelinosomes, produced by retinal neurons and glia. Myelinosomes are present in all nuclear and plexiform layers, in the synaptic terminals of photoreceptors, in the processes of retinal neurons and glial cells, and in the subretinal space. In vitro study shows that myelinosomes secreted by human retinal glial Müller MIO-M1 cells transfected with EGFP-mHTT-exon1 carry EGFP-mHTT-exon1 protein, as revealed by immuno-EM and Western-blotting. Myelinosomes loaded with mHTT-exon1 are incorporated by naive neuronal/neuroblastoma SH-SY5Y cells. This results in the emergence of mHTT-exon1 in recipient cells. This process is blocked by membrane fusion inhibitor MDL 28170. Conclusion: Incorporation of myelinosomes carrying mHTT-exon1 in recipient cells may contribute to HD spreading in the retina. Exploring ocular fluids for myelinosome presence could bring an additional biomarker for HD diagnostics.  相似文献   
96.
A new method for forming spherical, submicrometer ceramic oxide particles by the hydrolysis of emulsified alkoxide droplets is reported. Emulsions are formed of alkoxide droplets dispersed in an inert, polar solvent. The alkoxide droplets are hydrolyzed to form oxide particles by adding water to the emulsion. It was shown that individual droplets acted as "microreactors" and controlled the powder size, shape, and composition. Both single-oxide and mixed-oxide powders were formed by this technique.  相似文献   
97.
98.
The morphology, composition and the electrical and electrochemical behaviour of the anodic microporous layer, prepared by the galvanostatic anodisation of Ti after sparking, followed by galvanostatic deposition of Pt or Ir have been investigated. These electrodes are proposed to function as dimensionally stable anodes (DSAs). For Ti/TiO2/Pt electrodes, Pt is deposited within some of the micropores of the oxide film. In contrast, for Ti/TiO2/Ir, the metal is deposited preferentially on the top surface. This difference is thought to result from the position of the metal deposition potential with respect to the flat band potential of n-TiO2. Optical imaging of both types of DSA suggests that only a few sites on the surface are responsible for electron exchange at the DSA-electrolyte interface. C-AFM measurements of Ti/TiO2/Pt samples subjected to long-term anodic polarisation, suggest that the Ti-noble metal contact is progressively insulated by thickening of the TiO2 barrier layer, promoting passivation of the DSA. For Ir coated anodes, catalytic activity is directly related to the presence of Ir and to the stability of the catalytic oxide layer. Under Cu electrowinning conditions, the electrochemically formed hydrated Ir oxide was found to be catalytically less stable, than the iridium oxide film subjected to a heat treatment.  相似文献   
99.
Hepatic metabolism of the two main isomers of CLA (9cis-11 trans, 10trans-12cisC18∶2) was compared to that of oleic acid (representative of the main plasma FA) in 16 rats by using the in vitro method of incubated liver slices. Liver tissue samples were incubated at 37°C for 17h under an atmosphere of 95% O2/5%CO2 in a medium supplemented with 0.75 mM of FA mixture (representative of circulating nonesterified FA) and with 55 μM [1-14C]9cis-11 trans C18∶2, [1-14C]10trans-12cis C18∶2, or [1-14C]oleate. The uptake of CLA by hepatocytes was similar for both isomers (9%) and was three times higher (P<0.01) than for oleate (2.6%). The rate of CLA isomer oxidation was two times higher (49 and 40% of incorporated amounts of 9cis-11 trans and 10trans-12 cis, respectively) than that of oleate (P<0.01). Total oxidation of oleate and CLA isomers into [14CO2] was low (2 to 7% of total oxidized FA) compared to the partial oxidation (93 to 98%) leading to the production of [14C] acid-soluble products. CLA isoemrs escaping from catabolism were both highly desaturated (26.7 and 26.8%) into conjugated 18∶3. Oleate and CLA isomers were mainly esterified into neutral lipids (30%). They were slowly secreted as parts of VLDL particles (<0.4% of FA incorporated into cells), the extent of secretion of oleate and of 10trans-12 cis being 2.2-fold higher than that of 9cis-11 trans (P<0.02). In conclusion, this study clearly showed that both CLA isomers were highly catabolized by hepatocytes, reducing their availability for peripheral tissues. Moreover, more than 25% of CLA escaping from catabolism was converted into conjugated 18∶3, the biological properties of which remain to be elucidated.  相似文献   
100.
The goal of our study was to potentiate the effects of the ((R,R)-trans-1,2-diaminocyclohexane)-platinum(II) fragment [(DACH)Pt], known for its cytotoxic properties, either with tamoxifen (Tam), the most widely used antiestrogen in the treatment of hormone-dependent breast cancers, or with its active metabolite hydroxytamoxifen (hydroxy-Tam). We coupled Tam or hydroxy-Tam derivatives bearing a malonato group at the para position of the beta aromatic ring with the (DACH)Pt fragment. The malonato-Tam and malonato-hydroxy-Tam compounds were prepared through McMurry coupling of the appropriate ketones. The presence of the malonate group resulted in a pronounced stereospecificity in the reaction, since malonato-Tam was obtained only as the Z isomer, while malonato-hydroxy-Tam was obtained as an 80/20 E/Z mixture. Attribution of the isomeric structures was achieved by 2D NMR spectroscopy. The platinum complexes (DACH)Pt-malonato-Tam and (DACH)Pt-malonato-hydroxy-Tam were then prepared by coupling the barium salts derived from the malonato-Tam and malonato-hydroxy-Tam with the nitrate derived from (DACH)PtCl(2). Study of the biochemical properties of these two platinum complexes showed that, while the hydroxy-Tam complex is satisfactorily recognized by the estrogen receptor (relative binding affinity, RBA=6.4 %), the Tam complex is less well recognized (RBA=0.5 %). The effects of these complexes on two hormone-dependent breast cancer cell lines (MCF7 and MVLN) were studied in vitro. Both complexes showed an antiproliferative effect on MCF7 cells, and an antiestrogenic effect on MVLN cells. The observed effects appear to be essentially antihormonal, since incorporation of the (DACH)Pt fragment into the tamoxifen skeleton did not cause an increase in the cytotoxicity of the complexes.  相似文献   
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