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21.
Seed weight and seed size both are quantitative traits and have been considered as important components of grain yield, thus identification of quantitative trait loci (QTL) for seed traits in lentil (Lens culinaris) would be beneficial for the improvement of grain yield. Hence the main objective of this study was to identify QTLs for seed traits using an intraspecific mapping population derived from a cross between L. culinaris cv. Precoz (seed weight-5.1g, seed size-5.7mm) and L. culinaris cv. L830 (seed weight-2.2g, seed size-4mm) comprising 126 F8-RILs. For this, two microsatellite genomic libraries enriched for (GA/CT) and (GAA/CTT) motif were constructed which resulted in the development of 501 new genomic SSR markers. Six hundred forty seven SSR markers (including 146 previously published) were screened for parental polymorphism and 219 (33.8%) were found to be polymorphic among the parents. Of these 216 were mapped on seven linkage groups at LOD4.0 spanning 1183.7cM with an average marker density of 5.48cM. Phenotypic data from the RILs was used to identify QTLs for the seed weight and seed size traits by single marker analysis (SMA) followed by composite interval mapping (CIM) which resulted in one QTL each for the 2 traits (qSW and qSS) that were co-localized on LG4 and explained 48.4% and 27.5% of phenotypic variance respectively. The current study would serve as a strong foundation for further validation and fine mapping for utilization in lentil breeding programs.  相似文献   
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Nonhomologous end joining (NHEJ) is a recently described bacterial DNA double-strand break (DSB) repair pathway that has been best characterized for mycobacteria. NHEJ can religate transformed linear plasmids, repair ionizing radiation (IR)-induced DSBs in nonreplicating cells, and seal I-SceI-induced chromosomal DSBs. The core components of the mycobacterial NHEJ machinery are the DNA end binding protein Ku and the polyfunctional DNA ligase LigD. LigD has three autonomous enzymatic modules: ATP-dependent DNA ligase (LIG), DNA/RNA polymerase (POL), and 3′ phosphoesterase (PE). Although genetic ablation of ku or ligD abolishes NHEJ and sensitizes nonreplicating cells to ionizing radiation, selective ablation of the ligase activity of LigD in vivo only mildly impairs NHEJ of linearized plasmids, indicating that an additional DNA ligase can support NHEJ. Additionally, the in vivo role of the POL and PE domains in NHEJ is unclear. Here we define a LigD ligase-independent NHEJ pathway in Mycobacterium smegmatis that requires the ATP-dependent DNA ligase LigC1 and the POL domain of LigD. Mycobacterium tuberculosis LigC can also support this backup NHEJ pathway. We also demonstrate that, although dispensable for efficient plasmid NHEJ, the activities of the POL and PE domains are required for repair of IR-induced DSBs in nonreplicating cells. These findings define the genetic requirements for a LigD-independent NHEJ pathway in mycobacteria and demonstrate that all enzymatic functions of the LigD protein participate in NHEJ in vivo.  相似文献   
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The exposure of paddy fields to arsenic (As) through groundwater irrigation is a serious concern that may not only lead to As accumulation to unacceptable levels but also interfere with mineral nutrients in rice grains. In the present field study, profiling of the mineral nutrients (iron (Fe), phosphorous, zinc, and selenium (Se)) was done in various rice genotypes with respect to As accumulation. A significant genotypic variation was observed in elemental retention on root Fe plaque and their accumulation in various plant parts including grains, specific As uptake (29–167 mg kg?1 dw), as well as As transfer factor (4–45%). Grains retained the least level of As (0.7–3%) with inorganic As species being the dominant forms, while organic As species, viz., dimethylarsinic acid and monomethylarsonic acid, were non-detectable. In all tested varieties, the level of Se was low (0.05–0.12 mg kg?1 dw), whereas that of As was high (0.4–1.68 mg kg?1 dw), considering their safe/recommended daily intake limits, which may not warrant their human consumption. Hence, their utilization may increase the risk of arsenicosis, when grown in As-contaminated areas.  相似文献   
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The understanding of integral membrane protein (IMP) structure and function is hampered by the difficulty of handling these proteins. Aqueous solubilization, necessary for many types of biophysical analysis, generally requires a detergent to shield the large lipophilic surfaces of native IMPs. Many proteins remain difficult to study owing to a lack of suitable detergents. We introduce a class of amphiphiles, each built around a central quaternary carbon atom derived from neopentyl glycol, with hydrophilic groups derived from maltose. Representatives of this maltose-neopentyl glycol (MNG) amphiphile family show favorable behavior relative to conventional detergents, as manifested in multiple membrane protein systems, leading to enhanced structural stability and successful crystallization. MNG amphiphiles are promising tools for membrane protein science because of the ease with which they may be prepared and the facility with which their structures may be varied.  相似文献   
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George J  Srivastava AK  Singh R  Shukla Y 《Proteomics》2011,11(22):4411-4421
Cypermethrin, a synthetic pyrethroid insecticide is shown to exert carcinogenic effects in rodents; however, its underlying mechanism remains elusive. Here, we showed the effect of cypermethrin on protein expression involved in neoplastic transformation in mouse skin. Comparative protein expression profiles between untreated control and cypermethrin-treated mouse skin were explored using 2-DE. A total of 27 spots that were statistically significant (p<0.05) and differentially expressed in response to cypermethrin exposure were identified by MALDI-TOF/TOF and LC-MS/MS. Among them, six up-regulated proteins (carbonic anhydrase 3 (Ca 3), Hsp-27, S100A6, galectin-7, S100A9, S100A11) and one down-regulated protein (superoxide dismutase [Cu-Zn] (Sod 1)) are associated with cancer-related key processes. These selected dysregulated proteins were further validated in 2-DE gels of mouse skin treated with known tumorigens (benzo-[a]-pyrene, 12-O-tetradecanoyl-phorbol-13-acetate and mezerein), respectively. Comparative studies showed that Ca 3, S100A6, S100A9, S100A11 and Sod 1 are specific for stages of development and progression of tumors whereas Hsp-27 and galectin-7 are specific for tumor promotion stage by cypermethrin in mouse skin. Furthermore, these chosen proteins confirmed by Western blotting and immunofluorescence staining were consistent with changes in 2-DE check. This proteomic investigation for the first time provides key proteins that will contribute in understanding the mechanism behind cypermethrin-induced neoplastic transformation.  相似文献   
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It is important to understand the conformational biases that are present in unfolded states to understand protein folding. In this context, it is surprising that even a short tripeptide like AFA samples folded/ordered conformation as demonstrated recently by NMR experiments of the peptide in aqueous solution at 280 K. In this paper, we present molecular dynamics simulation of the peptide in explicit water using OPLS-AA/L all-atom force field. The results are in overall agreement with NMR results and provide some further insights. The peptide samples turn and extended conformational forms corresponding to minima in free energy landscape. Frequent transitions between the minima are observed due to modest free energy barriers. The turn conformation seems to be stabilized by hydrophobic interactions and possibly by bridging water molecules between backbone donors and acceptors. Thus the peptide does not sample conformations randomly, but samples well defined conformations. The peptide served as a model for folding-unfolding equilibrium in the context of peptide folding. Further, implications for drug design are also discussed.  相似文献   
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Hippophae salicifolia (HS) and Hippophae rhamnoides turkestanica (HRT) are abundantly found species of Hippophae in Himalayan region of India. As these plants thrive under extreme climatic conditions, it is suspected that these plants must have a unique adaptogenic property against high-altitude stress. To keeping these views in our mind, the present study was planned to evaluate the mechanism of action of aqueous extract of HS and aqueous extract of HRT against multiple stress [cold-hypoxia-restraint (C-H-R)] for their adaptogenic activity. The present study reported the adaptogenic activity of HS in facilitating tolerance to multiple stress, CHR in rats. Pre-treatment with aqueous extract of HS significantly attenuated reactive oxygen species (ROS) production, protein oxidation, and lipid peroxidation and also showed role in maintaining antioxidant status as similar to control rats. Since protein oxidation was decreased by pre-treatment of HS, protein homeostasis was also sustained by regulation of heat shock proteins (HSP70 and HSP60). Interestingly, heme oxygenase-1 (HO-1), Vascular Endothelial Growth Factor (VEGF), and nitric oxide (NO) level was also increased in HS pre-treated rats depicted its adaptogenic activity against multiple stress, CHR. Conclusively, aqueous extract of HS could use an adaptogen for high altitude-associated multiple stress (CHR).  相似文献   
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