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41.
A new Nipergasilus species is described from the gills of the grey mullet Valamugil cunnesius from several localities in India and Pakistan. The new species is closely related to Nipergasilus bora (Yamaguti, 1939) which is also recorded here on three species of grey mullet. The genus Nipergasilus is redefined in order to accommodate the second species.  相似文献   
42.
A new series of co-drugs was designed based on hybridising the dihydropteroate synthase (DHPS) inhibitor sulphonamide scaffold with the COX-2 inhibitor salicylamide pharmacophore through biodegradable linkage to achieve compounds with synergistic dual inhibition of COX-2/PGE2 axis and DHPS enzyme to enhance antibacterial activity for treatment of septicaemia. Compounds 5 b, 5j, 5n and 5o demonstrated potent in vitro COX-2 inhibitory activity comparable to celecoxib. 5j and 5o exhibited ED50 lower than celecoxib in carrageenan-induced paw edoema test with % PGE2 inhibition higher than celecoxib. Furthermore, 5 b, 5j and 5n showed gastric safety profile like celecoxib. Moreover, in vivo antibacterial screening revealed that, 5j showed activity against S.aureus and E.coli higher than sulfasalazine. While, 5o revealed activity against E.coli higher than sulfasalazine and against S.aureus comparable to sulfasalazine. Compound 5j achieved the target goal as potent inhibitor of COX-2/PGE2 axis and in vivo broad-spectrum antibacterial activity against induced septicaemia in mice.  相似文献   
43.
Calcium–calmodulin-dependent protein kinase IV (CAMK4) plays significant role in the regulation of calcium-dependent gene expression, and thus, it is involved in varieties of cellular functions such as cell signaling and neuronal survival. On the other hand, curcumin, a naturally occurring yellow bioactive component of turmeric possesses wide spectrum of biological actions, and it is widely used to treat atherosclerosis, diabetes, cancer, and inflammation. It also acts as an antioxidant. Here, we studied the interaction of curcumin with human CAMK4 at pH 7.4 using molecular docking, molecular dynamics (MD) simulations, fluorescence binding, and surface plasmon resonance (SPR) methods. We performed MD simulations for both neutral and anionic forms of CAMK4-curcumin complexes for a reasonably long time (150 ns) to see the overall stability of the protein–ligand complex. Molecular docking studies revealed that the curcumin binds in the large hydrophobic cavity of kinase domain of CAMK4 through several hydrophobic and hydrogen-bonded interactions. Additionally, MD simulations studies contributed in understanding the stability of protein–ligand complex system in aqueous solution and conformational changes in the CAMK4 upon binding of curcumin. A significant increase in the fluorescence intensity at 495 nm was observed (λexc = 425 nm), suggesting a strong interaction of curcumin to the CAMK4. A high binding affinity (KD = 3.7 × 10?8 ± .03 M) of curcumin for the CAMK4 was measured by SPR further indicating curcumin as a potential ligand for the CAMK4. This study will provide insights into designing a new inspired curcumin derivatives as therapeutic agents against many life-threatening diseases.  相似文献   
44.
A gene encoding chitinase from B. subtilis has been isolated after optimization of PCR conditions. It was cloned with two different prometers, T7 promoter of the pJET1.2/blunt cloning vector and the SP6 promoter of pGEM®-T Easy vector. After transforming E. coli DH5α, two transformants were selected, CHI-NRC-4 from the first vector and T-CHI-NRC-6 from the second vector, and used for further studies. The complete CDS sequence of chitinase gene was determined and submitted to GenBank with the accession number KX268692.1. Culture supernatants of E. coli (CHI-NRC-4) and E. coli (T-CHI-NRC-6) were investigated for their inhibitory effect on M. javanica egg hatch under laboratory conditions. Result showed up to 96% inhibition in egg hatching due to both E. coli transformants as compared to control which reflect the same expression efficiency of both used prometers. A greenhouse experiment was carried out to evaluate the nematicidal effect of culture supernatants of the two transformts E. coli (CHI-NRC-4) and E. coli (T-CHI-NRC-6) against M. javanica infected eggplant. Obtained results showed a significant reduction in nematode population in soil and roots and enhancement in eggplant growth parameters as compared to control.  相似文献   
45.
The aim of this study is to construct a new recombinant strain able to degrade cellulose efficiently. The endo-β-1, 3-1, 4 glucanase (bgls) gene was cloned from Bacillus subtilis BTN7A strain by using PCR technique. The specific primers of bgls gene were deduced. Optimization of PCR mixture and program were identified. The nucleotide sequence of bgls was placed in the public domain (GenBank accession number KM009051.1). The obtained bgls DNA was cloned with pGEM®-T Easy Vector. The recombinant plasmid designated as Bgls-NRC-1 was transformed into E. coli DH5α. The successful cloning of the bgls gene was tested either by PCR or by evaluating its expression in its new bacterial host. The bgls gene was expressed efficiently in E. coli and the enzyme activity of the transformant was compared to the enzyme activity of the donor bacterial strain. The new constructs produce much higher enzyme yields than the donor bacterial strain, they produce about 29% and about 57% higher cellulase specific activity at 37?°C and 55?°C respectively. Optimization of cellulolytic activity of the new recombinant strain were described. The effect of minimal medium supplemented with CMC or cellulose, or complete medium (LB) on bgls expression were tested, the order of cellulase activity production was CMC27.2?>?cellulose 21.9?>?LB 19.8?U/mg protein, respectively at 24?h. CMC was proved to be the best medium for cellulase production. Results also showed that double the initial inoculum resulted in more cellulase activities in all media.  相似文献   
46.
47.
Type and concentration of edible components, are two main factors which can be affected the chemical, microbial, quality, sensory properties and storage life of coated cheese. In this work, to optimize the concentrations of chitosan and Natamycin for coating Iranian white UF cheese response surface methodology was used. The effects of main edible coating components, chitosan (0.5–2.5%, w/w) and Natamycin (5–20 ppm) on pH, TSS, bacterial total count, yeast and mould population and starter of coated cheese were studied up to 3 weeks after storage at 4?±?2 °C. The obtained results indicated that the second-order polynomial models could be successfully generated with high coefficient of determination (R2?≥?0.9153) using experimental data for all the studied response variables. The optimum concentrations of chitosan and Natamycin were obtained at 1.6% w/w and 18.5 ppm, respectively which the predicted values for pH, TSS, bacterial total count, yeast and mould population and starter were 4.5, 37%, 12 cfu, 14 cfu and 346 cfu, respectively. The verification test was done at obtained optimum concentrations of the main edible components and the statistical analysis indicated insignificant (p?>?0.05) differences between the predicted and experimental values of the response variables.  相似文献   
48.
Evidence on the relationship between the vitamin D pathway and outcomes in melanoma is growing, although it is not always clear. We investigated the impact of measured levels of sun exposure at diagnosis on associations of vitamin D receptor gene (VDR) polymorphisms and melanoma death in 3336 incident primary melanoma cases. Interactions between six SNPs and a common 3′‐end haplotype were significant (p < .05). These SNPs, and a haplotype, had a statistically significant association with survival among subjects exposed to high UVB in multivariable regression models and exerted their effect in the opposite direction among those with low UVB. SNPs rs1544410/BsmI and rs731236/TaqI remained significant after adjustment for multiple testing. These results suggest that the association between VDR and melanoma‐specific survival is modified by sun exposure around diagnosis, and require validation in an independent study. Whether the observed effects are dependent or independent of vitamin D activation remains to be determined.  相似文献   
49.
A survey is given about the number and chromosomal position of rDNA loci in 45 Brassicaceae species. For 34 species, 5S and 45S rDNA loci have been localized by two-colour fluorescence in situ hybridization for the first time. These data show the variability of rDNA within karyotypes of the Brassicaceae, provide anchor points for (comparative) genetic maps, and might be important for studies on concerted evolution of internal transcribed sequence types of rDNA in cruciferous plants.  相似文献   
50.
Increasing insecticide resistance requires strategies to prolong the use of highly effective vector control compounds. The use of combinations of insecticides with other insecticides and phytochemicals is one such strategy that is suitable for mosquito control. In bioassays with Aedes aegypti and Culex annulirostris mosquitoes, binary mixtures of phytochemicals with or without synthetic insecticides produced promising results when each was applied at a LC25 dose. All mixtures resulted in 100% mortality against Cx. annulirostris larvae within 24 h rather than the expected mortality of 50%. All mixtures acted synergistically against Ae. aegypti larvae within the first 24 h except for one mixture that showed an additive effect. We conclude that mixtures are more effective than insecticides or phytochemicals alone and that they enable a reduced dose to be applied for vector control potentially leading to improved resistance management and reduced costs.  相似文献   
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