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Hojo H Igawa K Ohba S Yano F Nakajima K Komiyama Y Ikeda T Lichtler AC Woo JT Yonezawa T Takato T Chung UI 《Biochemical and biophysical research communications》2008,376(2):375-379
To effectively treat osteoporosis and other bone-loss disorders, small compounds that potently induce bone formation are needed. The present study initially attempted to establish a monitoring system that could detect osteogenic differentiation easily, precisely, and noninvasively. For this purpose, we established pre-osteoblastic MC3T3E1 cells stably transfected with the GFP reporter gene driven by a 2.3 kb fragment of rat type I collagen promoter (Col1a1GFP-MC3T3E1). Among these cells, we selected a clone that fluoresced upon osteogenic stimulation by BMP2. The GFP fluorescence intensity corresponded well to the intensity of alkaline phosphatase (ALP) staining and to the level of osteocalcin (Oc) mRNA. Using this system, we screened natural and synthetic compound libraries and thus identified an isoflavone derivative, glabrisoflavone (GI). GI induced ALP staining and Oc mRNA in a dose-dependent manner. The Col1a1GFP-MC3T3E1 system may be useful for identifying novel osteogenic drugs. 相似文献
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Screening and production of erythritol by newly isolated osmophilic yeast-like fungi 总被引:7,自引:0,他引:7
Twenty-eight erythritol-producing strains were isolated from pollen, honey and high sugar food samples collected in Taiwan. Amongst these, six strains (166-2, 262-1, 278-3, 440, 441 and 442) were high erythritol-producers with a yield higher than 30% for 30% glucose. The erythritol productivity of these strains ranged from 90.9 to 116.4 g l−1. 1H- and 13C-NMR analyses confirmed that the fermentation product was erythritol. The results of morphological and physiological studies indicate that strains 166-2, 262-1, 278-3, 440, and 442 may be members of the genus Moniliella. More studies are required to determine the taxonomic position of strain 441. The use of a medium containing 30% glucose and 1% yeast extract gave the highest erythritol productivity. On batch fermentation in a 5-l fermentor using strain 166-2, a maximal erythritol productivity of 111.0 g l−1 was obtained after cultivation for 144 h. 相似文献
86.
Screening and catalytic activity in organic synthesis of novel fungal and yeast lipases 总被引:2,自引:0,他引:2
Fernando Cardenas Emilio. Alvarez Maria-Soledad. de Castro-Alvarez Jose-Maria. Sanchez-Montero Manuel Valmaseda Steve W. Elson Jose-Vicente. Sinisterra 《Journal of Molecular Catalysis .B, Enzymatic》2001,14(4-6):111-123
A total of 969 microbial strains were isolated from soil samples and tested to determine their lipolytic activity by employing screening techniques on solid and in liquid media. Ten lipase-producing microorganisms were selected and their taxonomic identification was carried out. From these strains Achremonium murorum, Monascus mucoroides, Arthroderma ciferri, Fusarium poae, Ovadendron sulphureo-ochraceum and Rhodotorula araucariae are described as lipase-producers for the first time. Hydrolysis activity of the crude lipases against both tributyrin and olive oil was measured. Heptyl oleate synthesis was carried out to test the activity of the selected lipases as biocatalysts in organic medium. All the selected lipases were tested as biocatalysts in several organic reactions using unnatural substrates. Lipases from the fungi Fusarium. oxysporum and O. sulphureo-ochraceum gave the best yields and enantioselectivities in the esterification of carboxylic acids. F. oxysporum and Penicillium chrysogenum lipases were the most active ones for the acylation of alcohols without steric hindrance. A. murorum lipase is very useful for the esterification of menthol. F. oxysporum and Fusarium. solani lipases were very stereoselective in the synthesis of carbamates. 相似文献
87.
The fungi, Hirsutella rhossiliensis and Hirsutella minnesotensis, are two endoparasites of second-stage juveniles (J2) of the soybean cyst nematode (SCN), Heterodera glycines. The objective of this study was to screen for effective fungal isolates to control the nematode in laboratory and greenhouse assays. A total of 93 isolates of H. rhossiliensis and 25 isolates of H. minnesotensis were evaluated for parasitism of SCN J2 on cornmeal agar. Percentage of SCN J2 parasitized by the fungi varied among the fungal isolates. Most H. rhossiliensis isolates parasitized a high percentage of J2. The isolates of H. rhossiliensis obtained from bacteria-feeding nematodes, however, generally did not parasitize J2 on agar. H. minnesotensis parasitized fewer J2 on agar than did H. rhossiliensis . Forty isolates of H. rhossiliensis and four isolates of H. minnesotensis that parasitized a high percentage of J2 on agar were evaluated for their biocontrol potential in soil treated with microwave heating. Most isolates selected from the agar assay also parasitized a high percentage of J2 in the soil but there was variation among isolates. Pathogenicity of 14 isolates of H. rhossiliensis and four isolates of H. minnesotensis to the SCN was also investigated in the greenhouse using untreated field soil. Most isolates of H. rhossiliensis reduced SCN population density and increased plant growth when compared with 1% corn-grits control (culture media). One isolate (OWVT-1) of H. rhossiliensis reduced the SCN egg density by 95% and J2 density by 98% when compared with the control. Isolates of H. minnesotensis, however, neither reduced SCN density nor increased plant growth in the greenhouse. 相似文献
88.
Emma J. Shanks 《Analytical biochemistry》2010,396(2):194-10438
Activity of the pterin- and folate-salvaging enzymes pteridine reductase 1 (PTR1) and dihydrofolate reductase-thymidylate synthetase (DHFR-TS) is commonly measured as a decrease in absorbance at 340 nm, corresponding to oxidation of nicotinamide adenine dinucleotide phosphate (NADPH). Although this assay has been adequate to study the biology of these enzymes, it is not amenable to support any degree of routine inhibitor assessment because its restricted linearity is incompatible with enhanced throughput microtiter plate screening. In this article, we report the development and validation of a nonenzymatically coupled screening assay in which the product of the enzymatic reaction reduces cytochrome c, causing an increase in absorbance at 550 nm. We demonstrate this assay to be robust and accurate, and we describe its utility in supporting a structure-based design, small-molecule inhibitor campaign against Trypanosoma brucei PTR1 and DHFR-TS. 相似文献
89.
Rebecca R. Miles William Perry Joseph V. Haas Marian K. Mosior Mathias N'Cho Jian W. J. Wang Peng Yu John Calley Yong Yue Quincy Carter Bomie Han Patricia Foxworthy Mark C. Kowala Timothy P. Ryan Patricia J. Solenberg Laura F. Michael 《The Journal of biological chemistry》2013,288(9):6386-6396
Control of plasma cholesterol levels is a major therapeutic strategy for management of coronary artery disease (CAD). Although reducing LDL cholesterol (LDL-c) levels decreases morbidity and mortality, this therapeutic intervention only translates into a 25–40% reduction in cardiovascular events. Epidemiological studies have shown that a high LDL-c level is not the only risk factor for CAD; low HDL cholesterol (HDL-c) is an independent risk factor for CAD. Apolipoprotein A-I (ApoA-I) is the major protein component of HDL-c that mediates reverse cholesterol transport from tissues to the liver for excretion. Therefore, increasing ApoA-I levels is an attractive strategy for HDL-c elevation. Using genome-wide siRNA screening, targets that regulate hepatocyte ApoA-I secretion were identified through transfection of 21,789 siRNAs into hepatocytes whereby cell supernatants were assayed for ApoA-I. Approximately 800 genes were identified and triaged using a convergence of information, including genetic associations with HDL-c levels, tissue-specific gene expression, druggability assessments, and pathway analysis. Fifty-nine genes were selected for reconfirmation; 40 genes were confirmed. Here we describe the siRNA screening strategy, assay implementation and validation, data triaging, and example genes of interest. The genes of interest include known and novel genes encoding secreted enzymes, proteases, G-protein-coupled receptors, metabolic enzymes, ion transporters, and proteins of unknown function. Repression of farnesyltransferase (FNTA) by siRNA and the enzyme inhibitor manumycin A caused elevation of ApoA-I secretion from hepatocytes and from transgenic mice expressing hApoA-I and cholesterol ester transfer protein transgenes. In total, this work underscores the power of functional genetic assessment to identify new therapeutic targets. 相似文献
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