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991.
Inafuku M  Li C  Kanda Y  Kawamura T  Takeda K  Oku H  Watanabe H 《Lipids》2012,47(6):581-591
Natural killer (NK) T cells are well known to play important roles in both tumor rejection and the defense against infectious. Therefore, the antitumor potential of NKT cell-activating antigens have been the focus for the development of NKT cell-based immunotherapies. Up to now, several studies have revealed that the administrations of glycolipids (e.g. α-galactosylceramide) can successfully treat certain metastatic tumors. However, liver injuries appeared upon the application of these antigens. We previously examined the potential of using β-glucosylceramide (β-GlcCer) to inhibit tumor metastasis to the liver. The aim of this study was to determine the antimetastatic effects of β-GlcCer and its impact on the activation of NKT cells. Intraperitoneal administration of β-GlcCer enhanced the production of interferon-γ from hepatic lymphocytes containing NKT cells, and increased the cytotoxicity of hepatic lymphocytes against tumor cells. Moreover, β-GlcCer administration suppressed the hepatic metastasis of tumors in wild type (WT) mice, but not in CD1d (-/-) or Jα18 (-/-) mice. The drawback associated with the other glycolipids in liver injury was not noted in WT mice treated with the continuous daily administration of β-GlcCer for 2 weeks. The present study demonstrated that β-GlcCer treatment activates invariant NKT cells, thus resulting in the inhibition of tumor metastasis.  相似文献   
992.
Plant‐derived 3‐deoxyanthocyanidins are photochromic materials that are coloured under ultraviolet (UV) irradiation and decoloured under light‐shielded storage. In this study, the optimised solvent composition is investigated to enhance the photochromic performance of luteolinidin, a 3‐deoxyanthocyanidin derivative. The visible absorbance ratio between the solution after UV irradiation and after storage in the dark, an index of photochromic performance, was found to be affected by the pH of the solution, and the value reached a maximum when the pH of the solution was 5.7. The type of organic solvent, which is necessary to dissolve luteolinidin, also affected the photochromic performance. When diethylene glycol or dipropylene glycol was used, the value of the absorbance ratio was especially large. Furthermore, this optimised solvent composition displayed excellent photochromic properties with an extract from the sorghum grain shell containing a large amount of 3‐deoxyanthocyanins.  相似文献   
993.
Three porous coordination polymers {Fe(dpa)[Pt(CN)4]·G·nH2O} (1-G; dpa = 1,2-di(4-pyridyl)ethane, G = dpa, bibenzyl (bbz) and stilbene (stb)) have been prepared by using a long and flexible ligand dpa. These compounds formed analogous 3-D elongated Hofmann-type frameworks based on 2-D planar layers extended by Pt–CN–Fe linkages with dpa as flexible pillar ligands. 1-dpa showed a characteristic three-step spin transition (ST) in the temperature range 180–240 K. The ST behavior was reversibly modulated by dehydration and hydration processes in keeping with the three steps. 1-bbz and 1-stb exhibited a gradual three-step ST over the range 80–200 K and an abrupt ST with T c = 163 K. The guest-dependent cooperativity of the ST behavior is discussed by considering the flexibility of the framework and guest molecules.  相似文献   
994.
A novel technique utilizing the gelation reaction of natural polymers has been proposed for the separation of solid from liquid in difficult-to-filter colloidal suspensions. This technique is especially effective in the treatment of colloidal muddy water of high solid concentration, which is often produced as a byproduct of certain construction processes. Colloidal suspensions are mixed with a sodium alginate solution, and this mixture is added to a calcium chloride solution, resulting in the entrapping of colloidal particles by the calcium alginate gel. Gel suspensions are then drained gravitationally, followed by mechanical expression of gel particles. Fundamental aspects of this process are investigated by using sodium bentonite as an experimental material. The alginate-bentonite mixture is added dropwise to the calcium solution. Decreasing the droplet size of the mixture expedites gelation since the diffusion of calcium ions into droplets determines the rate of gelation reactions. Reducing the alginate content expedites expression of the gel since alginate content is inversely proportional to the rate of expression.  相似文献   
995.
Quantitative Determination of phosphatidylcholine by an HPLC-RI system   总被引:1,自引:0,他引:1  
The following describes the quantitative determining method for phosphatidylcholine (PC) using the HPLC-RI system which we have developed. It uses Lichromsorb, Si 60 (10 μm), 4.6 mm × 250 mm as the column and a mobile phase consisting of n-hexane/isopropanol/water =1:4:1. In this report, we compared data from selected high-purity (60–100 wt%) samples using the HPLC-RI, HPLC-UV and conventional TLC-P methods. Under the conditions we described, the HPLC-UV method was somewhat affected by fatty acid compositions. As a result, there were some inconsistencies in the measured values. However, the HPLC-RI method we propose was applicable to PC from both egg yolk and soybeans. In addition, the HPLC-RI method produced data which correlated well with data from the TLC-P method, and this data was highly accurate and exhibited satisfac-tory reproductibility.  相似文献   
996.
A novel positive resist was prepared by sensitizing poly(p-trimethylsilyloxystyrene) with p-nitro-benzyl-9, 10-diethoxyanthracene-2-sulfonate (NBAS) which was found to be a deep UV bleachable acid precursor. The silylated polymer is converted to alkaline soluble poly(p-hydroxy-styrene) in the presence of acid and a small amount of water. The photoresist gives high resolution positive patterns on imagewise exposure with deep UV light with a sensitivity of 15 mJ/cm2.  相似文献   
997.
Calcium homeostasis endoplasmic reticulum protein (CHERP) is colocalized with the inositol 1,4,5-trisphosphate receptor (IP3R) in the endoplasmic reticulum or perinuclear region, and has been involved in intracellular calcium signaling. Structurally, CHERP carries the nuclear localization signal and arginine/serine-dipeptide repeats, like domain, and interacts with the spliceosome. However, the exact function of CHERP in the nucleus remains unknown. Here, we showed that poly(A)+ RNAs accumulated in the nucleus of CHERP-depleted U2OS cells. Our global analysis revealed that CHERP regulated alternative mRNA splicing events by interaction with U2 small nuclear ribonucleoproteins (U2 snRNPs) and U2 snRNP-related proteins. Among the five alternative splicing patterns analyzed, intron retention was the most frequently observed event. This was in accordance with the accumulation of poly(A)+ RNAs in the nucleus. Furthermore, intron retention and cassette exon choices were influenced by the strength of the 5′ or 3′ splice site, the branch point site, GC content, and intron length. In addition, CHERP depletion induced anomalies in the cell cycle progression into the M phase, and abnormal cell division. These results suggested that CHERP is involved in the regulation of alternative splicing.  相似文献   
998.
999.
The alkyl derivatives of boehmite (alkoxyalumoxanes; AlO(OH)1?x (OR) x ) were synthesized by the reaction of aluminum triisopropoxide in straight-chain primary alcohols at 300 °C for 2 h in an autoclave. In the present work, pore structures of aluminas obtained by calcination of the alkyl derivatives of boehmite were examined. The alumina obtained from the ethyl derivative of boehmite had a broad pore-size distribution, while the pore-size of the alumina obtained from the dodecyl derivative of boehmite distributed in a narrow range in the mesopore region. The mode pore diameter of the latter alumina increased with the increase in calcination temperature (as-syn., 39 Å; 600 °C, 54 Å; 800 °C, 58 Å; 1000 °C, 68 Å), but narrow pore-size distribution was maintained even after calcination at high temperatures.  相似文献   
1000.
Dense ZrW2O8 was prepared by spark plasma sintering (SPS), using amorphous ZrW2O8 nanopowder as a raw material, at 873 K for 10 min. We investigated the effects of SPS conditions, such as sintering temperature, heating rate, and the discharge power that is expressed as the product of pulsed direct current and voltage, on the densification process of ZrW2O8. The relative density and microstructure of ZrW2O8 prepared by SPS were compared with those of ZrW2O8 prepared by hot pressing (HP). The relative density of ZrW2O8 prepared by HP at 873 K for 1 h was 63.1%. On the contrary, the relative density of ZrW2O8 prepared by SPS at 873 K for 10 min at a heating rate of 50 K/min was 98.6%. These results show that the discharge pressure that is proportional to discharge power enhances the densification and grain growth of ZrW2O8 in the SPS process.  相似文献   
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