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111.
112.
Toll-like receptors (TLRs), a family of transmembrane and cytosolic proteins, detect microbial patterns, initiating innate immune responses in various organisms. Although they are abundant, genetic characterization and functional differences of TLRs in economically important avian species such as chickens and turkeys have not been investigated in detail. In this study, the putative TLR5 coding region from turkey genome was sequenced, and its homology to other vertebrate species was analyzed. Secondary structure analysis revealed protein motifs typical of the chicken TLR5 protein structure, with 97% amino acid identity between them. mRNA expression profiling in adult turkeys revealed abundant TLR5 expression in a broad range of tissues. Stimulation with the TLR5 ligand flagellin resulted in the production of the inflammatory mediators interleukin (IL)-1beta, IL-6, and nitric oxide in peripheral blood mononuclear cells. To our knowledge, this is the first complete turkey TLR5 coding DNA sequence reported in sequence databases.  相似文献   
113.
Animal breeding in India has a long and chequered history. High pressure on agricultural land and increasing human population opened a new opportunity for the livestock and poultry sector as a promising food industry. Productivity of livestock in India is low due to less coverage of livestock under structured breeding programmes, inadequate nutrition and its entanglement with several socio‐economic issues. A bottom‐up approach to breeding policy formulation addressing local needs is required with assured flow of investments. Cattle slaughter is banned in India; hence, a legal policy to curb widespread indiscriminate mating is required which may incur substantial financial and infrastructural burdens for castration of stray males and strengthening of cow rehabilitation centres. Genetic evaluation of indigenous cattle with progeny testing (PT) requires substantial financial support, without affecting the already existing PT for exotic cattle breeds used in the local cross‐breeding programmes and PT of new genotypes obtained from crosses of exotic and local breeds of cattle and for purebred buffaloes. Small ruminants need special attention due to their socio‐economic importance in rural and often highly disadvantaged communities and because they are the second most important meat‐producing species after poultry. Genetic improvement of small ruminants should be accompanied by attention to shrinking grazing resources which would require strong political will together with financial support. The outreach of breeding programmes for small ruminants is currently limited; there is also a lack of linkage between the market and producers that discourages farmers from adopting clear breeding objectives like improvement in growth rate, as animals are seldom sold on weight basis. Apart from government agencies, involvement of private sector, non‐government organizations, local co‐operatives, self‐help groups and self‐sustainable community‐based breeding programmes can strengthen market linkages. Strengthening of the existing infrastructure along with technical input and skilled manpower is essential for achieving the breeding objectives.  相似文献   
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115.
Spinach (Spinacea oleracea L. cv. ‘Banarasi’), known to be responsive to potentially toxic elements, was investigated for chromium (Cr6 +) effect on iron metabolism and water relations. After 40 days growth in sand culture, a set of plants was supplied with 100 and 400 μM Cr6 + (potassium dichromate, K2Cr2O7), superimposed over the complete nutrient solution (control). Excess Cr6 + produced visual symptoms of toxicity and increased accumulation of Cr, more in roots than in leaves. Decreased concentration of chlorophylls and the activities of heme enzymes, catalase and peroxidase in excess Cr6 + may suggest interference of Cr in iron metabolism of plants. These changes associated with decrease in iron (Fe) accumulation in Cr6 + treated plants, indicate that by reducing absorption of Fe, Cr6 + impairs the Fe requiring steps of chlorophyll and heme biosynthesis. In spite of lower water saturation deficit, the leaves of Cr6 + treated plants showed a decrease in leaf water potential, associated with increase in diffusive resistance and lowering of transpiration rate along with proline accumulation indicates water stress. The changes observed in water stress parameters in Cr6 + treated plants indicate that excess supply of Cr6 + reduces the physiological availability of water.  相似文献   
116.
Monocrotophos (MCP), commonly known as azodrin, is one of the organophosphate (OP) pesticides extensively used in agricultural practices throughout the world. Channa punctatus were exposed to sublethal concentrations (0.96 and 1.86 mg/L) of monocrotophos for 15 and 60 days to assess the alterations in the level of some biochemical parameters in blood plasma. Significant alterations in all the biochemical parameters were found to be dose dependent. Hypoglycemia and hypocholesteremia were observed in plasma of fish at both exposure periods (15 and 60 days). Increased activities of glutamate-oxalacetate transaminase (GOT), glutamate-pyruvate transaminase (GPT), acid and alkaline phosphatase of blood plasma indicated hepatic tissue damage. Decrease in lactate dehydrogenase (LDH) content in plasma further indicated lower metabolic rate after 60 days of exposure. Significant decline in triglycerides content was observed in fish exposed to both sublethal concentrations of monocrotophos. We suggest that analysis of biochemical parameters in the fish blood may be useful in environmental biomonitoring.  相似文献   
117.
Fifty-five strains of Xanthomonas axonopodis pv. vignicola, isolated from blight and pustule symptoms of cowpea leaves, originating from 11 countries, were characterized for their carbon-source metabolization pattern using the Biolog GN microplate system. Great variation was found between strains according to origin. Dextrin, glycogen and succinamic acid were not used by strains from Benin, Uganda or Thailand, but by all the other strains (excluding two strains from Mozambique), whereas N-acetyl-D-glucosamine and malonic acid were used by the strains from Benin, Uganda and Thailand, but generally not by the other strains. The strains from Benin, Uganda and Thailand, as well as strains from Venezuela, Brazil and Mozambique, clustered separately from the others in multivariate analysis. Nineteen substrates were used by all the strains, 47 not by any strain and 29 only by some strains. No considerable differences were found between strains isolated from blight symptoms and from pustules. Virulence of strains was not related to the metabolic pattern. The Biolog database was not representative of the diversity of X. axonopodis pv. vignicola, since all strains were identified as Xanthomonas campestris, although belonging to eight pathovars, while only eight of nine strains from Benin and both strains from Thailand were identified as X. campestris pv. vignicola. The Biolog system appeared to be useful for characterizing the diversity of X. axonopodis pv. vignicola strains. A set of representative strains based on metabolic and molecular diversity, virulence and geographic origin is suggested for screening for resistant cowpea cultivars.  相似文献   
118.
Production of exopolysaccharides (EPS) can be used as a criteria for the isolation of stress tolerant microorganisms. In the present study, EPS-producing fluorescent pseudomonads were isolated from alfisols, vertisols, inseptisols, oxisols, and aridisols of different semiarid millet growing regions of India and were screened in vitro for drought tolerance in trypticase soy broth supplemented with different concentrations of polyethylene glycol (PEG6000). Out of the total 81 isolates, 26 could tolerate maximum level of stress (−0.73 MPa) and were monitored for the amount of EPS produced under maximum level of water stress. The strain GAP-P45, isolated from alfisol of sunflower rhizosphere, showed the highest level of EPS production under water stress conditions, was identified as Pseudomonas putida on the basis of 16S rDNA sequence analysis, and was used as seed treatment to study its effect in alleviating drought stress effects in sunflower seedlings. Inoculation of Pseudomonas sp. strain GAP-P45 increased the survival, plant biomass, and root adhering soil/root tissue ratio of sunflower seedlings subjected to drought stress. The inoculated bacteria could efficiently colonize the root adhering soil and rhizoplane and increase the percentage of stable soil aggregates. Scanning electron microscope studies showed the formation of biofilm of inoculated bacteria on the root surface and this, along with a better soil structure, might have protected the plants from the water stress.  相似文献   
119.
The ethanolic extract of Clerodendrum inerme leaves were screened for its hepatoprotective activity in CCl(4) (0.5 ml/kg, i.p) induced liver damage in Swiss albino rats at a dose of 200 mg /kg bw. The ethanolic extract of C. inerme significantly (P<0.001) decreases the serum enzyme alanine amino transferase (ALT), asparate amino transferase (AST), alkaline phosphates (ALP), triglycerides (TGL), total cholesterol (TC) and significantly increased the glutathione level. Silymarin (25 mg/kg), a known hepatoprotective drug used for comparison exhibited significant activity (P<0.001). The extract did not shown any mortality up to a dose of 2000 g/kg bw.  相似文献   
120.
To improve drought tolerance of potato, we bred four cultivars with large root mass and registered them as Konyu-1 to Konyu-4 in 2007. In this paper, we present the yield performance and the related aboveground characteristics of three Konyu cultivars and cv. Konafubuki (small root mass, one of the parents of these Konyu cultivars) in irrigated and droughted fields for 3 years. Consistent with our previous reports, we observed that the yield reduction in droughted fields relative to irrigated fields was less in Konyu cultivars than in Konafubuki. Konyu-2 showed the highest yield in both fields in all three experimental years. Konyu-2 and Konafubuki had a relatively high harvest index (HI) as a result of lower dry weight partitioning to the shoot regardless of water treatment. This characteristic contributed to the higher yield in the irrigated field in both cultivars compared with the other cultivars. In addition, Konyu-2 had a higher leaf/stem ratio coupled with a lower number of branches than the other cultivars. In the year of the most severe drought, the leaf area index remained below 3 (optimum value for intercept radiation) in Konafubuki, but not in Konyu-2 because of its high leaf/stem ratio. The present results suggest that in addition to large root mass, high HI coupled with high leaf/stem ratio with low number of branches may contribute to achieve high and stable yields in drought prone environments.  相似文献   
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