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81.
Bcl-2 is an anti-apoptotic member of the Bcl-2 family of proteins that protects cells from apoptosis induced by a large variety of stimuli. The protein BMRP (MRPL41) was identified as a Bcl-2 binding partner and shown to have pro-apoptotic activity. We have performed deletion mutational analyses to identify the domain(s) of Bcl-2 and BMRP that are involved in the Bcl-2/BMRP interaction, and the region(s) of BMRP that mediate its pro-apoptotic activity. The results of these studies indicate that both the BH4 domain of Bcl-2 and its central region encompassing its BH1, BH2, and BH3 domains are required for its interaction with BMRP. The loop region and the transmembrane domain of Bcl-2 were found to be dispensable for this interaction. The Bcl-2 deletion mutants that do not interact with BMRP were previously shown to be functionally inactive. Deletion analyses of the BMRP protein delimited the region of BMRP needed for its interaction with Bcl-2 to the amino-terminal two-thirds of the protein (amino acid residues 1-92). Further deletions at either end of the BMRP(1-92) truncated protein resulted in lack of binding to Bcl-2. Functional studies performed with BMRP deletion mutants suggest that the cell death-inducing domains of the protein reside mainly within its amino-terminal two-thirds. The region of BMRP required for the interaction with Bcl-2 is very relevant for the cell death-inducing activity of the protein, suggesting that one possible mechanism by which BMRP induces cell death is by binding to and blocking the anti-apoptotic activity of Bcl-2.  相似文献   
82.
Molecular Biology Reports - SMAD2 is a critical signal transducer molecule in the TGFβ- SMAD pathway which is also known for its tumor suppressor role. Genetic variations in SMAD2 render cells...  相似文献   
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84.
The design and synthesis of 4-alkynyl pyrazole derivatives has led to the identification of new class of PDE4 inhibitors. All these compounds were accessed for the first time via a facile Pd/C-CuI-PPh(3) mediated C-C bond forming reaction between an appropriate pyrazole iodide and various terminal alkynes. In vitro PDE4B inhibitory properties and molecular modeling studies of some of the compounds synthesized indicated that 4-alkynyl pyrazole could be a promising template for the discovery of novel PDE4 inhibitors.  相似文献   
85.
A number of novel 1,8-disubstituted 5,5-dimethyl-4,5-dihydro-1H-benzo[g]indazoles based on a conformationally restricted pyrazole framework have been designed as potential inhibitors of PDE4. All these compounds were readily prepared by using simple chemistry strategy. The in vitro PDE4B inhibitory properties and molecular modeling studies of some of the compounds synthesized along with the X-ray single crystal data of a representative compound is presented.  相似文献   
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87.
This research describes and presents some biological aspects of five fish species from carangidae family including: Alepes djedaba, Ulua mentalis, Alectis indica, Carangoides coeruleopinnatus, and Carangoides bajad in the Iranian waters of the northern Persian Gulf (Hormozgan Province, Iran). Samples were collected from April to September 2016. The fishing gears were gill nets (80, 100, 120 and 145 mm stretched mesh size), bottom and midwater trawls (30, 40 and 75 mm stretched mesh size in cod‐end) of local and commercial fishery. The b values of length–weight relationships ranged from 2.512 (95% CL = 0.054) for U. mentalis to 2.953 (95% CL = 0.155) for C. coeruleopinnatus and the correlation coefficient values (r2) were high for all species.  相似文献   
88.
The objective of this work was to examine the time-dependent pro-oxidant versus antioxidant effect of various doses of vitamin E used commonly in experimental studies. Erythrocyte activity of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and plasma lipid peroxidation levels were investigated following biweekly intramuscular administration of 100, 300 and 600 mg/kg of vitamin E at a baseline time point, and additionally at 2, 4 and 6 weeks after initiating treatment. Vitamin E had an antioxidant effect when administered at low doses over short time periods, and increased the activity of antioxidant enzymes. At higher doses and over longer time periods, it increased the level of lipid peroxidation, and attenuated the activity of antioxidant enzymes. These results suggest that time-dependent variations in vitamin E effects should be considered in design and interpretation of experimental antioxidant studies, as well as during clinical trials.  相似文献   
89.
Escherichia coli strain BL21(DE3) was tested as a delivery vector for gene transfer to a murine P388D1 macrophage cell line using a 96-well high-throughput assay. Five recombinant strains of E. coli were compared to identify the effect recombinant listeriolysin O (LLO) and associated gene expression parameters had on final delivery of a luciferase reporter gene. Listeriolysin O, native to Listeria monocytogenes and used here in an effort to improve final gene delivery, was expressed from plasmid and chromosomal locations under the control of constitutive Tet or inducible T7 promoters. The E. coli vectors delivered the luciferase reporter gene to the P388D1 line with success assessed by recording luciferase luminescence activity within the macrophage cells. The assay allowed rapid analysis and evaluation of each E. coli strain tested with strain BL21(DE3) harboring a chromosomal copy of the T7-driven LLO gene showing the greatest relative measure of gene delivery. Strains were separately assayed for LLO activity and exhibited a trend of maximum gene delivery between the lowest and highest recorded LLO activities.  相似文献   
90.
Lignocellulose‐derived hydrolyzates typically display a high degree of variation depending on applied biomass source material as well as process conditions. Consequently, this typically results in variable composition such as different sugar concentrations as well as degree and the presence of inhibitors formed during hydrolysis. These key obstacles commonly limit its efficient use as a carbon source for biotechnological conversion. The gram‐negative soil bacterium Pseudomonas putida KT2440 is a promising candidate for a future lignocellulose‐based biotechnology process due to its robustness and versatile metabolism. Recently, P. putida KT2440_xylAB which was able to metabolize the hemicellulose (HC) sugars, xylose and arabinose, was developed and characterized. Building on this, the intent of the study was to evaluate different lignocellulose hydrolyzates as platform substrates for P. putida KT2440 as a model organism for a bio‐based economy. Firstly, hydrolyzates of different origins were evaluated as potential carbon sources by cultivation experiments and determination of cell growth and sugar consumption. Secondly, the content of major toxic substances in cellulose and HC hydrolyzates was determined and their inhibitory effect on bacterial growth was characterized. Thirdly, fed‐batch bioreactor cultivations with hydrolyzate as the carbon source were characterized and a diauxic‐like growth behavior with regard to different sugars was revealed. In this context, a feeding strategy to overcome the diauxic‐like growth behavior preventing accumulation of sugars is proposed and presented. Results obtained in this study represent a first step and proof‐of‐concept toward establishing lignocellulose hydrolyzates as platform substrates for a bio‐based economy.  相似文献   
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