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991.
Soybean hulls as a dietary fiber source for dogs.   总被引:4,自引:0,他引:4  
In Exp. 1, soybean hull samples were obtained from nine sources across the United States and analyzed for nutrient content to determine their suitability for inclusion in dog diets. Compositional data revealed variation in both the amount of total dietary fiber (TDF; 63.8 to 81.2%) in the soybean hulls and the ratio of insoluble:soluble fiber (5.0:1 to 15.4:1). Crude protein content varied widely among sources, ranging from 9.2 to 18.7%. An in vivo trial (Exp. 2) was conducted using a premium dog diet containing 3.0, 4.5, 6.0, 7.5, or 9.0% soybean hulls (DM basis). There was a negative linear effect (P < .05) of soybean hull inclusion in the diet on DM, OM, TDF, and GE total-tract digestibilities, as well as on calculated ME. Crude protein and fat digestibilities were unaffected by treatment. Based on these results, ileally cannulated dogs were fed diets containing 6.0, 7.5, or 9.0% soybean hulls (DM basis) in addition to diets containing either 0% supplemental fiber or 7.5% beet pulp (Exp. 3). Nutrient digestion at the ileum was unaffected by inclusion of supplemental fiber. Total tract digestion of DM, OM, and GE was lower ( P < .05) for diets containing supplemental fiber when compared with the diet containing 0% fiber. Crude protein and fat digestibilities were unaffected by treatment. There was no difference in nutrient digestibility between those diets containing soybean hulls and a diet containing beet pulp. Soybean hull inclusion in the diet resulted in a negative linear effect (P < .05) on calculated ME, in addition to lowering ME (P < .05) when compared with the 0% fiber control diet. Calculated ME for dogs fed a 7.5% beet pulp-containing diet was lower (P < .05) than that for dogs fed the soybean hull-containing diets. Results indicate that soybean hulls can be an effective dietary fiber source in dog diets.  相似文献   
992.
993.
The proximate composition of pulp, skin and seeds of prickly pear cactus (Opuntia ficus indica) was investigated and is reported on a dry weight basis. The most abundant component of the pulp and skin was ethanol-soluble carbohydrates. Pulp contained glucose (35%) and fructose (29%) while the skin contained essentially glucose (21%). Protein content was 5.1% (pulp), 8.3% (skin) and 11.8% (seeds). Starch was found in each of the three parts of the fruit. Pulp fibers were rich in pectin (14.4%), skin and seeds were rich in cellulose (29.1 and 45.1%, respectively). Skin was remarkable for its content of calcium (2.09%) and potassium (3.4%). Prickly pear is a neglected nutritional source which should be more widely used because of its potential nutrient contribution.  相似文献   
994.
Reactive cyclodextrin (RCD) based nanoemulsion and loaded with coconut oil in presence of Tween 80 emulsifying agent for development of antimicrobial medical cotton fabrics is the subject of current research. RCD based nanoemulsion was prepared at different stirring duration, viz, 2, 4, 6 and 24 h in presence of Tween 80. This was done in order to induce varieties in size and morphology of the nanoemulsion. The coconut oil encapsulated RCD based nanocomposite was precipitated as powder using centrifugation technique for 60 min at 4500 rpm and the resulted powder was investigated using TEM and SEM techniques. The images that provided by these techniques confirmed the nano-sized scale of the coconut oil loaded RCD nanocomposite. In addition, the entrapment efficiency of coconut oil loaded RCD based nanoemulsion after centrifugation was calculated and was found to more than 93 %; this is a proof for the successful inclusion of the coconut oil inside the cavity of RCD molecules. Moreover, the obtained RCD based nanoemulsions were applied to bleached cotton fabrics as per the pad-dry-cure method. The as treated cotton fabrics were monitored for nitrogen content, add-on, mechanical properties and morphology vis-a-vis those similarly treated fabrics but using the as prepared microemulsion of RCD loaded with coconut oil in absence of Tween 80. The morphological structure of cotton fabrics treated with the nanoemulsion in question was also examined using SEM technique. Moreover, the biological activity of the nanoemulsion finished fabrics before and after being submitted to 20 washing cycles was investigated against different types of bacteria and fungi as per the inhibition zone method. Results obtained signify: (i) deposition on the fabric of coconut oil loaded RCD nanoemulsion; (ii) the add-on of the nanoemulsion on the surface of cotton fabric is a manifestation of the stirring duration, proofing the formation of ultrafine oil nanoemulsion which penetrates the fabric surface; (iii) the finished fabrics display antimicrobial activity with clear excellent inhibition zone even after 20 washing cycles, indicating the protection of these fabrics for human beings from harmful microbes. In conclusion, the cotton fabrics treated with nanoemulsion of RCD loaded coconut oil is considered as an effective super antimicrobial medical textile against pathogenic microorganisms of both bacteria and fungus species.  相似文献   
995.
Yield gains from rain-fed wheat (Triticum aestivum L.) production, particularly in areas experiencing intermittent and terminal dry spells, can be realized through integrated breeding with promising genetic and genomic resources using appropriate methodologies. This enables targeted recombination of novel genes for drought tolerance and selection of desirable genotypes. Continuous exploration of new sources of genetic variation and introgression of suitable genes into elite drought-susceptible genotypes, including via transgenic approaches, and the use of genome editing could offer exciting future prospects in acquiring drought-tolerant wheat genotypes. This review highlights the available genetic resources, the major wheat genebanks and databases, as well as the breeding methodologies for drought tolerance in wheat, including prebreeding, conventional breeding, hybrid breeding, and genomics-assisted breeding. The potential of genetic modification through the transgenic and genome-editing approaches is also discussed. Emphasis is placed on how best these breeding methods can be brought together to develop strategies aimed at improving drought tolerance in wheat.  相似文献   
996.
997.
New Forests - Canopy openings due to harvesting practices constitute a disturbance that changes the environmental conditions of microsites. Its impact on the relative performance of the...  相似文献   
998.
The organization of bacteria in biofilms is one of the adaptive resistance mechanisms providing increased protection against conventional treatments. Thus, the search for new antibiofilm agents for medical purposes, especially of natural origin, is currently the object of much attention. The objective of the study presented here was to explore the potential of extracts derived from three seaweeds: the green Ulva lactuca, the brown Stypocaulon scoparium, and the red Pterocladiella capillacea, in terms of their antibiofilm activity against P. aeruginosa. After preparation of extracts by successive maceration in various solvents, their antibiofilm activity was evaluated on biofilm formation and on mature biofilms. Their inhibition and eradication abilities were determined using two complementary methods: crystal violet staining and quantification of adherent bacteria. The effect of active extracts on biofilm morphology was also investigated by epifluorescence microscopy. Results revealed a promising antibiofilm activity of two extracts (cyclohexane and ethyl acetate) derived from the green alga by exhibiting a distinct mechanism of action, which was supported by microscopic analyses. The ethyl acetate extract was further explored for its interaction with tobramycin and colistin. Interestingly, this extract showed a promising synergistic effect with tobramycin. First analyses of the chemical composition of extracts by GC–MS allowed for the identification of several molecules. Their implication in the interesting antibiofilm activity is discussed. These findings suggest the ability of the green alga U. lactuca to offer a promising source of bioactive candidates that could have both a preventive and a curative effect in the treatment of biofilms.  相似文献   
999.
A comparative analysis of the state of microbial communities in kurgans, paleosols buried under them, and background surface soils in the dry steppe zone of the Lower Volga region has been performed. It is shown that the population density of microorganisms of various trophic groups in the kurgans is an order of magnitude lower than that in the A1 horizon of the corresponding buried paleosols and background surface soils within the areas of chestnut, light chestnut, and solonetzic soils. The respiration activity of the microbial communities in the upper layer of the kurgans is comparable with that in the A1 horizons of the background surface soils; it decreases in the deeper layers of the kurgans. In the A1 horizon of the buried paleosols, the respiration activity is approximately the same as in the deep layers of the kurgans. In the buried paleosols, the spatial variability in the numbers of soil microorganisms is approximately the same or somewhat higher than that in the background surface soils. The spatial variability in the respiration activity of the buried paleosols is two to four times higher than that in the background surface soils.  相似文献   
1000.
The genetic diversity available in sweetpotato has not been explored to develop dual-purpose sweetpotato varieties (DPSVs). The objectives of this study were to assess the level of phenotypic diversity present among sweetpotato varieties grown in Rwanda, and to select suitable parents for breeding DPSVs. Fifty-one diverse sweetpotato genotypes were evaluated in field trials conducted at the Rubona and Karama experimental stations of the Rwanda Agriculture Board using a 6?×?9 unbalanced alpha lattice design with three replications. Genotypes and sites showed significant interaction (P??1) and RW11-2419 (20.18?t?ha?1). RW11-4923 and Wagabolige were the best performers for vine yield, producing 23.67 and 23.45?t?ha?1 of vines, respectively. Ukerewe performed well for its DRY (7.09?t?ha?1), while RW11-4923 had the highest mean dry vine yield (5.17?t?ha?1). RW11-2910 and 8-1038 had root-to-vine ratios of 2.0 and 1.5, respectively, suggesting their suitability as breeding parents, to breed DPSVs. Two main phenotypic groups with 10 sub-groups were detected through cluster analysis. Principal component analysis showed that the first four components accounted for 76.33% of the phenotypic variation present among the 51 genotypes. The selected sweetpotato genotypes that had a combination of high storage root yields and heavy vine production should be used as parents in developing DPSVs, concurrently incorporating farmer-preferred traits.  相似文献   
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