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81.
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83.
Cyclooxygenase-2 (COX-2) catalyzed synthesis of prostaglandin E2 and it associates with tumor growth, infiltration, and metastasis in preclinical experiments. Known inhibitors against COX-2 exhibit toxicity. Therefore, it is of interest to screen natural compounds like flavanoids against COX-2. Molecular docking using 12 known flavanoids against COX-2 by FlexX and of ArgusLab were performed. All compounds showed a favourable binding energy of >-10 KJ/mol in FlexX and > -8 kcal/mol in ArgusLab. However, this data requires in vitro and in vivo verification for further consideration.  相似文献   
84.
Chemical evolution of a HTS-based fragment hit resulted in the identification of N-(1-adamantyl)-2-[4-(2-tetrahydropyran-4-ylethyl)piperazin-1-yl]acetamide, a novel, selective T-type calcium channel (Ca(v)3.2) inhibitor with in vivo antihypertensive effect in rats.  相似文献   
85.
Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very large, which may complicate disease prevention and control.  相似文献   
86.
Specific antibodies against anti-human FVIII/vW protein were isolated by affinity chromatography on glutaraldehyde-activated gel (Ultrogel AcA22). They were coupled directly with peroxidase or visualized with anti-rabbit IgG (sheep)-peroxidase (Institut Pasteur). Fab fragments of the same specific antibodies were prepared to enhance the intracellular penetration and coupled to peroxidase. In washed human platelets, staining was observed on the plasma membrane and in the canalicular system, whereas in previous studies whole specific antibodies incubated with fixed platelets showed the labeling only on the plasma membrane. After thrombin activation, the release of granules containing FVIII/vW protein was better visualized in the surface canalicular system. This localization was discussed in regard to the exocytosis process: membrane fusion, granule labeling.  相似文献   
87.
The oribatid mite fauna of Turkey is still relatively poorly known. The present paper adds two species of oribatid mites to the known Turkish fauna viz., Oribatula (Zygoribatula) debilitranslamellata (Kulijev, 1962) and O. (Z.) exilis (Nicolet, 1855). Both species are characterised by large, prominent lamellar cusps, with the lamellar setae inserted apically on the cusps, and by the presence of distinct translamellae. They can be distinguished, however, by the smaller lamellae, absence of cuspidal teeth, narrowly fusiform sensilli and, 13 pairs of thin, smooth, apically almost flagellate notogastral setae, in O. (Z.) debilitranslamellata, and by the wider lamellae, presence of cuspidal teeth, widely fusiform sensilli, and 14 pairs of thin, smooth notogastral setae, with seta c (1) slightly thicker and minutely barbed in O. (Z.) exilis. The following species have been previously reported from Turkey: O. (Z.) cognata (Oudemans, 1902), O. (Z.) undulata (Berlese, 1917), O. (Z.) terricola Van der Hammen, 1952, and O. (Z.) lanceolata Grobler, Bayram & Cobanoglu, 2004.  相似文献   
88.
Choudhary MI  Sultan S  Khan MT  Rahman AU 《Steroids》2005,70(12):798-802
The microbial transformation of the 17alpha-ethynyl-17beta-hydroxyandrost-4-en-3-one (1) (ethisterone) and 17alpha-ethyl-17beta-hydroxyandrost-4-en-3-one (2) by the fungi Cephalosporium aphidicola and Cunninghamella elegans were investigated. Incubation of compound 1 with C. aphidicola afforded oxidized derivative, 17alpha-ethynyl-17beta-hydroxyandrosta-1,4-dien-3-one (3), while with C. elegans afforded a new hydroxy derivative, 17alpha-ethynyl-11alpha,17beta-dihydroxyandrost-4-en-3-one (4). On the other hand, the incubation of compound 2 with the fungus C. aphidicola afforded 17alpha-ethyl-17beta-hydroxyandrosta-1,4-dien-3-one (5). Two new hydroxylated derivatives, 17alpha-ethyl-11alpha,17beta-dihydroxyandrost-4-en-3-one (6) and 17alpha-ethyl-6alpha,17beta-dihydroxy-5alpha-androstan-3-one (7) were obtained from the incubation of compound 2 with C. elegans. Compounds 1-6 exhibited tyrosinase inhibitory activity, with compound 6 being the most potent member (IC(50)=1.72 microM).  相似文献   
89.
Amino acid sequence analysis of fungal histidine acid phosphatases displaying phytase activity has revealed a conserved eight-cysteine motif. These conserved amino acids are not directly associated with catalytic function; rather they appear to be essential in the formation of disulfide bridges. Their role is seen as being similar to another eight-cysteine motif recently reported in the amino acid sequence of nearly 500 plant polypeptides. An additional disulfide bridge formed by two cysteines at the N-terminus of all the filamentous ascomycete phytases was also observed. Disulfide bridges are known to increase both stability and heat tolerance in proteins. It is therefore plausible that this extra disulfide bridge contributes to the higher stability found in phytase from some Aspergillus species. To engineer an enhanced phytase for the feed industry, it is imperative that the role of disulfide bridges be taken into cognizance and possibly be increased in number to further elevate stability in this enzyme.  相似文献   
90.
Barley, Hordeum vulgare L., is well adapted to subarctic Alaska growing conditions, but little is known about its response to grasshopper defoliation. A field experiment was conducted to study dry matter and grain yield in response to a combination of grasshopper defoliation and weeds in 2002 and 2003 near Delta Junction, AK (63 degrees 55' N, 145 degrees 20' W). Barley plants at third to fourth leaf stage were exposed to a combination of two levels of weeds (present or absent) and four densities of grasshoppers (equivalent to 0, 25, 50, and 75 grasshoppers per m2) of third to fourth instars of Melanoplus sanguinipes (F). Dry matter accumulation by the barley plants was determined at three times during the growing seasons: approximately 10 d after introduction of the grasshoppers, shortly after anthesis, and at maturity. Dry matter accumulation and grain yield were much lower in 2003 than in 2002, probably due to very low levels of soil moisture early in the growing season of 2003. Head clipping accounted for a greater portion of yield loss in 2003 than in 2002. The percentage of reduction in harvestable yield due to grasshoppers remained fairly constant between years (1.9 and 1.4 g per grasshopper per m2 in 2002 and 2003, respectively) despite a large difference in overall yield. Examination of the yield components suggest that yields were reduced by the early season drought in 2003 primarily through fewer seeds per head, whereas grasshoppers in both years reduced average seed weight, but not numbers of seeds.  相似文献   
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