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271.
Circadian rhythmicity is present in almost every aspect of the living world and effects of drugs on various life forms are no exception. This study was undertaken to find out the circadian variation in the analgesic activity of aspirin and to correlate the variations with the blood levels of salicylate at that time. The model used was the application of radiant heat to the tail of rats for analgesic activity. Aspirin exhibited maximum activity when administered at 12:00 h, although this difference was not statistically significant. Also, there was no correlation between the levels of salicylate in the blood and the activity of aspirin. Due to the presence of this trend towards increased activity at 12:00 h, it may thus be worthwhile to conduct similar studies, in patients of chronic arthritis, in order to find out the time(s) at which, aspirin if administered will be most useful.  相似文献   
272.
273.
Aromatic amino acid metabolism during organogenesis in rice callus cultures   总被引:1,自引:0,他引:1  
The activity during root and shoot initiation of key enzymes involved in aromatic amino acid metabolism was examined in rice ( Oryza sativa L. cv. Bala) callus cultures. Increased activities of the enzymes quinate:NAD+ oxidoreductase (EC 1.1.1.24), shikimate kinase (EC 2.7.1.71), chorismate mutase (EC 5.4.99.5), anthranilate synthase (EC 4.1.3.27) and tryptophan synthetase (EC 4.2.1.20) were noticed in organ-forming callus compared to proliferating callus of rice, especially prior to the visible manifestation of form. These results suggest a correlation between organogenesis and the aromatic amino acid pathway.  相似文献   
274.
Cane is one of the important forest products after timber, form an integral part of a rural and tribal population of many of the tropical countries of South East Asia, Africa and America. Calamus nambariensis Becc. has been recognized as endemic and threatened cane to the North East region of India. The plant is restricted to only two pockets of Assam with a poor population size. Therefore, conservation of this plant through proper scientific investigation is utmost necessary. The present investigation has as its objectives to study the distribution, estimation of population size, standardization of suitable micropropagation methods for reintroduction and reinforcement in suitable wild habitat as determined by ecological niche modelling (ENM) for the purposes of conservation. For improving the conservation status of the species, potential area and habitat for reintroduction was determined using maximum entropy (MaxEnt) distribution modelling algorithm. The population size in both the site was found to be very poor i.e., mean density, frequency of occurrence and abundance in relation to other associated species was 0.600, 29.26 and 2.307 in Nambor Reserve Forest whereas 0.526, 27.407 and 2.112 respectively in Gibbon Wildlife Sanctuary. Macropropagation of C. nambariensis was standardized here through seed germination which was found to be more efficient in terms of time and cost which revealed 87% germination in treated seeds, followed by 61% only for untreated seeds till 90 days. It was also observed that seedlings in the hilly slope of Gibbon Wildlife Sanctuary (reinforcement) showed high survivability than that of the hilly slop of Lahorijan Reserve Forest (reintroduction). Further, survival rate was measured for 24 months, which revealed significantly very high on an average of 97.85% in both the locations, while 1200 numbers of C. nambariensis plantlets were transferred to the field. The present study could change the population size of C. nambariensis in its natural habitat, proving effective means for preventing extinction and improving conservation status of the plant.  相似文献   
275.
Plant Cell, Tissue and Organ Culture (PCTOC) - Soil salinity and water-deficit conditions often affect crop productivity in groundnut. Therefore, developing transgenic groundnut that can grow under...  相似文献   
276.
Molecular Biology Reports - Previously, we isolated CDS of Ziziphus nummularia isoform ZnJClpB1-C from heat stress-tolerant genotype Jaisalmer. To further functionally validate ZnJClpB1-C assumed...  相似文献   
277.
A series of twenty compounds ( 23 – 42 ) were synthesized and characterized by spectral studies in order to explore newer antimicrobial compounds. The majority of the synthesized compounds reported significant antimicrobial properties against various pathogenic bacterial and fungal strains with the help of tube dilution method. Significant activities (MIC ranging from 3.9 to 15.62 μg/ml) have been shown against Gram-negative and Gram-positive bacteria with. In contrast, moderate to outstanding antibacterial activity was reported versus Gram-negative bacteria such as E. coli and P. aeruginosa along with Gram-positive bacteria such as S. aureus and B. subtilis. While antifungal activity was moderate to excellent against two fungus strains (Candida tropicalis, Candida glabrata). Compounds 25 and 34 had the utmost activity versus Gram-positive and Gram-negative bacteria too. The antifungal activity of compound 35 was comparable to that of standard. In-silico Molecular docking evaluations were performed for antibacterial and antifungal activities against the target DNA gyrase A (PDB: 1AB4) and 14 alpha-sterol demethylase enzyme (PDB: 1EA1), respectively. The dock score for typicals compounds for antibacterial and antifungal activity were −4.733 and −9.4, respectively. The three-dimensional QSAR examination was carried out by multiple linear regression (SA-MLR) with good predictive power (r2=0.9105, q2=0.8011). Establishment of several interactions between the ligand 25 and 34 and the active site of residue of both receptors, enable the ligand 25 and 34 to be fit well in the pocket of the active site, as seen in Molecular dynamics simulations analysis. Thus, data suggest that these ligands could be further explored as potential precursors to develop antimicrobial drugs.  相似文献   
278.
A quantitative comparison was made on the fractionation of pepsin-digested horse antivenoms by ammonium sulfate (AS) fractional precipitation and ion-exchange chromatography on Q-Sepharose. In the precipitation process, pepsin digested horse anti-Naja kaouthia serum was precipitated by 30% saturated AS followed by 50% saturated AS. The recovery of antibody activity [as measured by an enzyme-linked immunosorbent assay (ELISA) against the cobra postsynaptic neurotoxin 3] from the 30–50% saturated AS precipitate was 53% with a 1.93-fold purification. For the chromatographic process, the behavior of the horse antitoxin antibody and its F(ab′)2 fragments was first studied. The pepsin digested horse serum was then desalted on a Bio-gel P-2 column followed by chromatography on Q-Sepharose using a linear gradient (20 mM Tris-HCl, pH 8.0 containing 0.0 to 0.5 M NaCl). A peak containing primarily the F(ab′)2 antibody could be obtained. This peak constituted 73% of the total antivenom activity with 2.08-fold purification. The total recovery of antibody activity by the chromatographic process was 90%. The yield of antibody activity was about 2-fold higher than that reported previously with other fractionation procedures. The implications of these results for the refining of horse therapeutic antivenoms are discussed.  相似文献   
279.
Callus was induced from mature seeds of two cultivars of Setaria italica (L.) on Murashige and Skoog's medium (1962) supplemented with 2mg/l 2,4-D and 0.5 mg/l KN. Regenerating ability of the callus was better in the cultivar 315 compared to 212. Organogenesis was influenced not only by cytokinin, but also by the sucrose concentration in the medium. High frequency (80%) plant regeneration was achieved and quantified on the basis of callus fresh weight. The ability of the callus (cultivar 212) to regenerate whole plants was retained until the 5th passage, but during the 6th passage it declined considerably.Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - KN Kinetin - BAP 6-benzylaminopurine - MS Murashige and Skoog basal medium  相似文献   
280.
Background Sorghum, the C4 dry-land cereal, important for food, fodder, feed and fuel, is a model crop for abiotic stress tolerance with smaller genome size, genetic diversity, and bio-energy traits. The heat shock proteins/chaperonin 60s (HSP60/Cpn60s) assist the plastid proteins, and participate in the folding and aggregation of proteins. However, the functions of HSP60s in abiotic stress tolerance in Sorghum remain unclear.MethodsGenome-wide screening and in silico characterization of SbHSP60s were carried out along with tissue and stress-specific expression analysis.ResultsA total of 36 HSP60 genes were identified in Sorghum bicolor. They were subdivided into 2 groups, the HSP60 and HSP10 co-chaperonins encoded by 30 and 6 genes, respectively. The genes are distributed on all the chromosomes, chromosome 1 being the hot spot with 9 genes. All the HSP60s were found hydrophilic and highly unstable. The HSP60 genes showed a large number of introns, the majority of them with more than 10. Among the 12 paralogs, only 1 was tandem and the remaining 11 segmental, indicating their role in the expansion of SbHSP60s. Majority of the SbHSP60 genes expressed uniformly in leaf while a moderate expression was observed in the root tissues, with the highest expression displayed by SbHSP60-1. From expression analysis, SbHSP60-3 for drought, SbHSP60-9 for salt, SbHSP60-9 and 24 for heat and SbHSP60-3, 9 and SbHSP10-2 have been found implicated for cold stress tolerance and appeared as the key regulatory genes.ConclusionThis work paves the way for the utilization of chaperonin family genes for achieving abiotic stress tolerance in plants.  相似文献   
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