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91.

Background  

Two or more species are cryptic, if they are morphologically similar, biologically distinct, and misclassified as a single species. Cryptic species complexes were recently discovered within many bat species and we suspect that the bent-wing bat, Miniopterus schreibersii, found in Europe, northern Africa, and Asia Minor, could also form such a complex. Populations of M. schreibersii decline in most of the European countries and the species is currently listed as Near Threatened in the IUCN Red List. Finding that M. schreibersii is not a single species, but a species complex, would have a considerable impact on its conservation strategies, as the abundance of each component taxon would be much smaller than the one estimated for the nominal species.  相似文献   
92.
Recognition of peptides bound to major histocompatibility complex (MHC) class I molecules by T lymphocytes is an essential part of immune surveillance. Each MHC allele has a characteristic peptide binding preference, which can be captured in prediction algorithms, allowing for the rapid scan of entire pathogen proteomes for peptide likely to bind MHC. Here we make public a large set of 48,828 quantitative peptide-binding affinity measurements relating to 48 different mouse, human, macaque, and chimpanzee MHC class I alleles. We use this data to establish a set of benchmark predictions with one neural network method and two matrix-based prediction methods extensively utilized in our groups. In general, the neural network outperforms the matrix-based predictions mainly due to its ability to generalize even on a small amount of data. We also retrieved predictions from tools publicly available on the internet. While differences in the data used to generate these predictions hamper direct comparisons, we do conclude that tools based on combinatorial peptide libraries perform remarkably well. The transparent prediction evaluation on this dataset provides tool developers with a benchmark for comparison of newly developed prediction methods. In addition, to generate and evaluate our own prediction methods, we have established an easily extensible web-based prediction framework that allows automated side-by-side comparisons of prediction methods implemented by experts. This is an advance over the current practice of tool developers having to generate reference predictions themselves, which can lead to underestimating the performance of prediction methods they are not as familiar with as their own. The overall goal of this effort is to provide a transparent prediction evaluation allowing bioinformaticians to identify promising features of prediction methods and providing guidance to immunologists regarding the reliability of prediction tools.  相似文献   
93.
p38 mitogen-activated protein kinase (MAPK) belongs to the MAPK superfamily, phosphorylating serine and/or threonine residues of the target proteins. The activation of p38 MAPK leads to cell growth, differentiation, inflammation, survival or apoptosis. In this study, we tested the effect of two highly specific and potent inhibitors of p38 MAPK (namely, SB203580 and SB202190) on human breast cancer cell line MDA-MB-231 to elucidate the controversial role of p38 MAPK on cell proliferation and/or cell migration/metastasis further. It was determined that the IC50 value of SB203580 was 85.1 µM, while that of SB202190 was 46.6 µM, suggesting that SB202190 is slightly more effective than SB203580. To verify the effect of each inhibitor on cell proliferation and cytotoxicity, the cells were treated with various doses of SB203580 and SB202190 and examined using iCELLigence system. No significant effect of 1 and 5 µM of both inhibitors were seen on cell proliferation as compared to the DMSO-treated control cells for up to 96 h. On the other hand, both SB203580 and SB202190 significantly prevented cell proliferation at a concentration of 50 µM. SB202190 was again more effective than SB203580. Afterwards, we tested the effect of each inhibitor on cell migration using wound assay. Both SB203580 and SB202190 significantly reduced cell migration in a time-dependent manner at a concentration of 50 µM. However, interestingly it was observed that a low and noncytotoxic dose of 5 µM of SB203580 and SB202190 also did cause significant cell migration inhibition at 48 h of the treatment, corroborating the fact that p38 MAPK pathway has a critical role in cell migration/metastasis. Then, we tested whether each p38 MAPK inhibitor has any effect on cell adhesion during a treatment period of 3 h using iCELLigence system. A concentration of only 50 µM of SB202190 reduced cell adhesion for about 1.5 h (p < 0.001); after that period of time, cell adhesion in 50 µM SB202190-treated cells returned to the level of the control cells. To determine the mechanism of growth and cell migration inhibitory effects of p38 MAPK inhibitors, the activation/inactivation of various proteins and enzymes was subsequently analyzed by PathScan® Intracellular Signaling Array kit. The ERK1/2 phosphorylation level was not modified by low concentrations (1 or 5 µM) of SB202190 and SB203580; while a high concentration (50 µM) of both inhibitors caused significant reductions in the ERK1/2 phosphorylation. In addition, it was determined that both p38 MAPK inhibitors caused significant increases on the Ser15 phosphorylation of mutant p53 in MDA-MB-231 under these experimental conditions; while SB202190 was more potent than SB203580.  相似文献   
94.
Folic acid (FA), is a group B vitamin, has high reactive oxygen radicals quenching ability, resulting in protection against oxidative damage in aerobic cell. Acetaminophen (N-acetyl-p-aminophenol, APAP) is a nonsteroidal anti-inflammatory drug, and can promote oxidative damage in liver and kidney tissues. The aim of this study was to investigate whether folic acid has protective effects on oxidative liver and kidney injury caused by experimental APAP toxication. Forty female Sprague dawley rats were divided into 5 groups; control, APAP, FA, APAP+FA, and APAP+N-acetylcysteine (NAC) groups. APAP toxication was induced by oral gavage (3 g/kg bodyweight). FA (20 mg/kg bodyweight) and NAC (150 mg/kg bodyweight) were given by oral gavage to the specified groups. Oxidant and antioxidant parameter were determined in liver and kidney tissues. In addition, the liver and kidney tissues were histological evaluated. When compared with APAP group, superoxide dismutase (SOD) and catalase activities and glutathione levels were statistically higher, malondialdehyde (MDA) level and myeloperoxidase activity (except liver tissue) were statistically lower in both APAP+FA and APAP+NAC. Liver and kidney MDA level and kidney SOD activity were significantly lower in APAP+NAC group compared with APAP+FA group. Co-administration of NAC with APAP was found to provide protection, but hepatic cords were defective in some places and some glomerular tubules also had dilatation. Necrotic areas was reduced in the liver and the glomerular structure was in good condition in the APAP+FA group. As a result, FA might have a protective effect against APAP-induced hepato-nephrotoxicity and oxidative stress in rat.  相似文献   
95.
Salicylic acid is an NSAID with serious side effects on the GIS. The side effects of salicylic acid on the GIS are slightly reduced by acetylating salicylic acid. 12 new ester analogs of salicylic acid were synthesized with high yields in this study. The chemical structures of the synthesized compounds were characterized by 1H-NMR, 13C-NMR, and HRMS spectra. The inhibitory potential of the compounds was evaluated on COXs by in vitro and in silico studies. The COX2 inhibitory activity of the most potent inhibitor MEST1 (IC50: 0.048 μM) was found to be much higher than the COX2 inhibitory activity of aspirin (IC50: 2.60 μM). In docking studies, the strongest inhibitor among the compounds synthesized was predicted to be MEST1, with the lowest binding energy. Docking studies revealed that MEST1 extends from the hydrophobic channel to the top of the cyclooxygenase active site, forming various interactions with residues in the binding pocket.  相似文献   
96.
Abstract

In this study, we aimed to synthesize copper oxide nanoparticles (CuONPs) mediated by plant extract in an environmentally friendly way and to reveal their potential biological activities. Here we synthesized CuONPs by using different concentrations of aqueous leaf extract of Thymbra spicata at 80?°C to obtain Ts1CuONPs and Ts2CuONPs. Biosynthesized nanoparticles were characterized by using UV-Vis, AFM, FTIR, SEM-EDS, TEM, DLS and zeta potential analysis. The antibacterial activity of the nanoparticles was determined by calculation of the inhibition zone and minimum inhibitory concentration against selected bacterial strains. Moreover, the antioxidant activity of the as-synthesized nanoparticles was evaluated based on DPPH radical scavenging activity. The results indicate that the as-synthesized NPs have an average size of 26.8 and 21?nm for Ts1CuONPs and Ts2CuONPs, respectively. The formed CuONPs have more antibacterial action on gram-positive bacteria compared to gram-negative bacteria. In addition, CuONPs demonstrated good inhibition activity against biofilm formation of Staphylococcus aureus (S. aureus). Furthermore, the results showed that the smaller size of the CuONPs caused the higher cytotoxicity on L929 mouse fibroblast cells. The as-synthesized CuONPs exhibit antibacterial and antibiofilm potential against S. aureus, indicating that they may be attractive candidates to use in future therapeutic applications.  相似文献   
97.
Choices are not only communicated via explicit actions but also passively through inaction. In this study we investigated how active or passive choice impacts upon the choice process itself as well as a preference change induced by choice. Subjects were tasked to select a preference for unfamiliar photographs by action or inaction, before and after they gave valuation ratings for all photographs. We replicate a finding that valuation increases for chosen items and decreases for unchosen items compared to a control condition in which the choice was made post re-evaluation. Whether choice was expressed actively or passively affected the dynamics of revaluation differently for positive and negatively valenced items. Additionally, the choice itself was biased towards action such that subjects tended to choose a photograph obtained by action more often than a photographed obtained through inaction. These results highlight intrinsic biases consistent with a tight coupling of action and reward and add to an emerging understanding of how the mode of action itself, and not just an associated outcome, modulates the decision making process.  相似文献   
98.
We used both highly variable mitochondrial and nuclear loci to investigate the large mouse‐eared bat species complex in the Western Palaearctic to clarify their systematic position. Although mitochondrial lineages show no species segregation and some haplotypes are shared between Myotis myotis and Myotis blythii sensu lato, Bayesian clustering methods based on multilocus genotypes indicate highly concordant nuclear and morphological species assignment. These multilocus, nuclear analyses detected only a single putative F1 hybrid in the extensive areas of sympatry sampled, thus confirming the biological species status of M. myotis and M. blythii s.l. We propose that the strong cytonuclear discordance in these species complex results from a combination of prior spatial isolation of the two species in different glacial refugia, followed by a succession of mitochondrial introgression events that occurred during the eastward and westward expansions of M. myotis and of M. blythii, respectively. The nuclear markers further indicate the presence of a notable genetic discontinuity within M. myotis that broadly separates populations into an eastern and a western component with an overlap zone in the Balkans. This eastern and western discontinuity is also apparent in the mitochondrial lineages with the D haplogroup largely confined to samples found in Thrace and Asia Minor. None of these genetic discontinuities correspond to the distribution of the two commonly recognized M. myotis subspecies (myotis and macrocephalicus). We also show that distinct morphological subspecies within M. blythii (oxygnathus, omari, risorius and lesviacus) in Europe and the near‐East do not correlate with significant evolutionarily units, whether identified by mitochondrial or nuclear data and thus only represent local morphological variants with little taxonomic relevance.  相似文献   
99.
The biological characteristics of eels from the Asi River, Turkey, were assessed between December 2017 and November 2018. Eels were sampled monthly using fyke nets (operated by professional fishermen), yielding a total of 509 specimens. Total length and weight were measured, sex, age and maturity stages (silver or yellow eel) were determined. Catch Per Unit Effort (CPUE) was calculated for both biomass per unit effort and numbers caught on a monthly and annual basis. The length-weight relationships (LWRs) of silver and yellow eel was W = 0.009*TL3.22 (n = 262) and W = 0.0106*L3.09 (n = 247), respectively. The age of the sampled fish ranged from year class II to VI. Von Bertalanffy growth parameters were estimated as L=69.25 cm, K = 0.43 1/year, t0= −0.41 and phi prime index ( ǿ )= 3.31 for all samples. The overall eel fishing mortality rate (F) was 0.31 year-1, and the exploitation and survival rates of silver stage eels were estimated with 30% and 39%, respectively.  相似文献   
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