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Agricultural industrialization and the subsequent reliance on pesticides has resulted in numerous unintended consequences, such as impacts upon the environment and by extension human health. Eco‐efficiency is a strategy for sustainably increasing production, while simultaneously decreasing these externalities on ecological systems. Eco‐efficiency is defined as the ratio of production to environmental impacts. It has been widely adopted to improve chemical production, but we investigate the challenges of applying eco‐efficiency to pesticide use. Eco‐efficiency strategies include technological innovation, investment in research and development, improvement of business processes, and accounting for market forces. These components are often part of integrated pest management (IPM) systems that include alternatives to pesticides, but its implementation is often thwarted by commercial realities and technical challenges. We propose the creation and adoption of an eco‐efficiency index for pesticide use so that the broad benefits of eco‐efficient strategies such as IPM can be more readily quantified. We propose an index based upon the ratio of crop yield to a risk quotient (RQ) calculated from pesticide toxicity. Eco‐efficiency is an operational basis for optimizing pest management for sustainability. It naturally favors adoption of IPM and should be considered by regulators, researchers, and practitioners involved in pest management. © 2019 Society of Chemical Industry  相似文献   
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With the availability of an ultraweak chemiluminescence analyzer, it is possible to monitor the production of a specific oxygen-derived reactive species, such as hydroxyl radical ((*)OH), whenever a suitable chemiluminescent probe is obtainable. Reported herein is the development of a rapid and specific method for detecting (*)OH production using a specific probe, indoxyl-beta-glucuronide (IBG), a low-level chemiluminescence emitter. Using the Fenton reagent as a source of (*)OH, it was shown that IBG could elicit a very strong intensity of chemiluminescence (CL) (16200 +/- 200 photon counts/s). Conversely, IBG was shown to be insensitive to either superoxide radical or hydrogen peroxide with their CL intensities nearly close to the background values (25 +/- 5 and 180 +/- 20 photon counts/s, respectively). Furthermore, it was also shown that this IBG-based CL production could be effectively quenched by the addition of (*)OH scavengers such as sodium salicylate, dimethyl sulfoxide, and penicillamine to the assay system. Taken together, these data indicate that IBG is a specific CL probe suitable for monitoring the production of (*)OH. This system demonstrated inhibitory activities of various aqueous extracts of food constituents on the CL of hydroxyl radicals generated by Fenton's reagents with the order of scavenging efficiencies being Prunus mume > Cordyceps sinensin > Lilium lancifolium > Astragalus membranceus.  相似文献   
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SUMMARY: Spatio-temporal variation of the sergestid shrimp Acetes intermedius in the coastal waters of southwestern Taiwan was investigated based on 1546 samples collected by 13 commercial fishing vessels from July to October 1996. Adult sergestid shrimp started a down-estuary migration with the increased river discharge associated with heavy summer rainfall. Fishing season for this species was to commence after that. In July, the shrimp stock was found on the shallow continental shelf off Tungkang and Fangshan. They mainly aggregated in Kaoping Canyon off Tungkang during August and September occurring at very high densities. In October, the shrimp returned to the coastal waters off Tungkang and Fangshan at lower densities. The heavy rainfall is a factor that triggers the shrimps to make a down-estuary migration that could reduce competition for food between adults and their offspring during the period of high river discharge. When the northeast monsoon prevailed, the sergestid shrimp moved back to the estuaries and the fishing season was terminated.  相似文献   
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Grouper iridovirus (GIV) belongs to the Ranavirus genus and is one of the most important viral pathogens in grouper, particularly at the fry and fingerling stages. In this study, we identified and characterized the GIV‐2L gene, which encodes a protein of unknown function. GIV‐2L is 1242 bp in length, with a predicted protein mass of 46.2 kDa. It displayed significant identity only with members of the Ranavirus and Iridovirus genera. We produced mouse monoclonal antibodies against the GIV‐2L protein by immunizing mice with GIV‐2L‐His‐tag recombinant protein. By inhibiting de novo protein and DNA synthesis in GIV‐infected cells, we showed that GIV‐2L was a late gene during the viral replication. Finally, immunofluorescence microscopy revealed that GIV‐2L protein accumulated in both the nucleus and cytoplasm of infected cells. These results offer important insights into the pathogenesis of GIV.  相似文献   
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落花生之黄曲毒素防治与其保健植物化合物之探讨   总被引:1,自引:0,他引:1  
落花生是全球熟悉与普遍消费的作物,其特殊之香气与酥脆质地吸引绝大多数消费者的味口。然而,由于落花生可能被黄曲毒素产生菌污染产毒,导致许多消费者常将落花生与黄曲毒素(系一种天然致癌物质)联想在一起,因而犹豫甚至拒绝进食含落花生之产品。落花生虽然是黄曲毒素产生菌生长之良好基质,但必须遭受其侵入,且得到充分生长才会产毒。田间栽种时有适当灌溉、采收后花生荚果迅速干燥,以及良好仓储条件,是落花生采收前后有效降低黄曲毒素污染的最重要方法。加工时,先将花生仁轻度焙烤,再脱膜并以色差电子自动筛检,则能更进一步将被霉菌污染之花生仁筛除,筛选后之花生仁可加工制作安全无虞之高品质食品。另外,有鉴于黄曲毒素产生菌普遍存在于土壤中,但采收后之健康花生荚或花生仁几乎均无黄曲毒素之污染,经探讨得知,落花生具有生合成二苯乙烯类化合物(包括熟知的白藜芦醇在内之植物防御素)以抵抗微生物入侵之本能。因此,落花生可经由发芽制备花生芽作为机能蔬菜,并促进生合成二苯乙烯类化合物,包括白藜芦醇,Arachidin-1,Arachidin-3及Isopentadienylresveratrol(IPD)等,这些二苯乙烯类化合物目前已知,具有相当值得重视的抗氧化与抗发炎活性,具有进一步开发作为饮食补充或保健产品之潜力。  相似文献   
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Food safety is one of the major concerns in every country regardless of the economic and social development. The frequent occurrence of food scandals in the world has led the Chinese government to implement several strategies to fortify the food supply system to a high food safety standard. This relies heavily on laboratory testing services but conventional methods for detection of food contaminants and toxicants are limited by sophisticated sample preparation procedures,long analysis time,large instruments and professional personnel to meet the increasing demands. In this review,we have incorporated most of the current and potential rapid detection methods for many notorious food contaminants and toxicants including microbial agents,toxic ions,pesticides,veterinary drugs and preservatives,as well as detection of genetically modified food genes and adulterated edible oil. Development of rapid,accurate,easy-to-use and affordable testing methods could urge food handlers and the public to actively screen for food contaminants and toxicants instead of passively relying on monitoring by the government examination facility. This review also provides several recommendations including how to encourage the public to engage in the food safety management system and provide optimal education and financial assistance that may improve the current Chinese food safety control system.  相似文献   
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