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41.
复合微生物制剂对重茬草莓生长及产量品质的影响研究   总被引:5,自引:0,他引:5  
试验研究了复合微生物制剂对重茬草莓植株生长及产量品质的影响。结果表明,复合微生物制剂对重茬未消毒土壤的草莓黄萎病防效达76.9%~84.6%。无论土壤是否消毒,复合微生物制剂均可提高草莓叶片的光合速率和叶绿素含量,促进草莓植株的生长,使物候期提前;显著提高草莓果实维生素C和可溶性糖的含量,改善果实品质和风味;草莓增产14.21%~16.20%。同时复合微生物制剂还可以改善土壤的理化性状,提高土壤肥力。  相似文献   
42.
我国SPF鸡胚生产与质量控制现状分析   总被引:1,自引:1,他引:0  
从生产能力、饲养方式、微生物质量监测等方面介绍了我国SPF鸡胚发展概况,对我国SPF鸡胚生产与质量控制现状进行了调查与分析,并对存在的问题提出建议.经调查,2012年我国有20家SPF鸡生产企业生产SPF鸡胚年产量约5050万枚,其中年产600万枚以上的企业有3家,300万~600万枚的企业有4家,10家企业年产量在100万~200万枚之间,其他3家企业年产量少于100万枚.从供需情况可以看出,目前我国SPF鸡胚生产数已供大于求略有结余.  相似文献   
43.
采用防雨棚池栽试验,研究灌溉模式和施氮量对水稻土壤肥力和水分利用效率的影响.结果表明,灌溉模式与施氮量对土壤化学特性、土壤微生物学特性、产量及水分利用效率有着显著影响.与常规灌溉相比,控制灌溉条件土壤有机质含量、全氮含量、全钾含量、速效磷含量、速效钾含量、细菌数量、真菌数量和水分利用效率增加,碱解氮含量和放线菌数量降低.随着施氮量增加,土壤有机质含量、全氮含量、碱解氮含量、放线菌和真菌数量增加,而全磷含量、全钾含量、速效磷和速效钾含量降低,产量和水分利用效率呈现先增加后降低的趋势.在本研究条件下,以控制灌溉模式,施氮量180 kg·hm-2,产量达到11 495 kg·hm-2,节本增效效应最佳.  相似文献   
44.
The microbiological quality of 18 commercially available in Spain ready-to-eat fish products containing Engraulidae was evaluated through application of the corresponding ISO procedures for total mesophilic aerobic microbial counts, detection and enumeration of enterobacteria, and detection of Staphylococcus spp. All isolates were identified to the species level using two different biochemical methods: the API® test and the Biolog® identification system. The most commonly occurring contaminants found were Enterobacteriaceae—such as Citrobacter freundii and other Citrobacter species, Enterobacter cloacae, Cronobacter sakazakii, Hafnia alvei, Pantoea, Proteus ssp., and Escherichia coli. The presence of such opportunistic pathogens and contaminant microflora was confirmed in 61% of the foods sampled.  相似文献   
45.
This paper reviewed the strategies and methods of screening for microorganisms having strong ability bensulfuron-methyl (BSM), and discussed BSM degradation pathways and factors affecting its microbial metabolism prospected the research emphasis in the future to remove Finally, it  相似文献   
46.
Influence of emulsified or non-emulsified common carp roe oil (CRO) and carp defatted roe hydrolysate (CDRH) on properties of crucian carp (Carassius auratus) sausages was determined during 30-day storage at 4°C. Sausages containing CRO and CDRH were lighter and had better textural properties including hardness, gumminess, and chewiness. These textural attributes were significantly higher in the sample prepared with pre-emulsified CRO and 7 g/100 g CDRH (p < 0.05). The sausages fortified with CDRH also presented better microstructure, as evidenced by fewer voids and smaller oil droplets. When incorporated at 7 g/100 g, CDRH could significantly reduce microbial spoilage in sausages in terms of the total viable count and the psychrophilic bacterial count (p < 0.05); however, pre-emulsification had no significant effect on antibacterial activity of hydrolysate in the samples (p > 0.05). Sausages with pre-emulsified roe oil and 7 g/100 g hydrolysate were more resistant against lipid oxidation and had a higher level of polyunsaturated fatty acids, especially docosahexaenoic acid and eicosapentaenoic acid after 30 days of storage at 4°C. Furthermore, the sausages with pre-emulsified CRO and 7 g/100 g CDRH exhibited better organoleptic properties at day 30.  相似文献   
47.
作物叶酸检测方法的研究进展   总被引:5,自引:1,他引:4  
叶酸是一种水溶性的维生素,是介导一碳单位转移极其重要的辅助因子。由于人类不能自身合成叶酸,而且作物中叶酸的含量通常较低,尤其是在谷物中含量更低,所以叶酸缺乏是一个全球性的问题。目前正通过基因工程或育种技术来提高作物中的叶酸水平,如何获得作物中各种叶酸衍生物含量的可靠数据非常重要。介绍了植物叶酸的提取过程,以及各种叶酸检测方法的原理、适用范围和各自的优缺点;重点阐述了微生物法和高效液相色谱法的方法学建立、原理以及目前的应用情况,并进行了展望。  相似文献   
48.
ABSTRACT

Postmortem biochemical and microbiological changes in loricariid catfish (Pterygoplichthys disjunctivus) muscle were evaluated during ice storage for 20 days. Values of pH remained stable for 15 days (7.4 ± 0.2), and total volatile base-nitrogen (TVB-N) remained under acceptable limits throughout storage, with a final value of 25.2 ± 3.3 mg N/100 g muscle at Day 20. Adenosine-5´-triphosphate (ATP) and derivatives followed a postmortem degradation pattern similar to other species, with the K-value being the best freshness loss indicator. Biochemical and microbiological changes indicated that the shelf life of iced loricariid catfish muscle was 15 days under optimal (0°C) storage conditions.  相似文献   
49.
以藤黄微球菌(标准号28001)为工作菌,用圆滤纸片法测定环丙沙星在牛奶中的残留.结果表明,环丙沙星在牛奶中的最低检测限为 0.08 μg/mL.该方法精密度良好,变异系数小于15%,操作简便,不需特殊设备,样品用量少,易于推广,适用于环丙沙星的半定量分析.  相似文献   
50.
In order to minimize the effects of porcine reproductive and respiratory syndrome (PRRS) on stillbirth, mummification, and neonatal mortality in swine herds, many producers have vaccinated their herds using a modified-live virus vaccine. The purpose of this study was to determine the association of the PRRS modified-live vaccine and reproductive performance by stage of gestation when the vaccine was administered. A total of 47 swine herds from Ontario and Manitoba, Canada, and from the mid-western USA were included in the study. Participating farms had vaccinated all of their sows at one point in time when they used the vaccine for the first time. The reproductive performance of sows that farrowed in the year prior to use of the vaccine was compared to that of sows vaccinated in each of five stages of gestation and in the gestation that followed the initial use of the vaccine. Sows vaccinated at any time during gestation had a reduced number of pigs born alive, a reduced number of pigs weaned per litter, and increased number of stillborn pigs and an increased number of mummified pigs compared to the sows that farrowed prior to use of the vaccine. The largest association was seen in sows that were vaccinated in the last four weeks of gestation. The largest losses were observed in those herds that were vaccinated concurrently with the initial PRRS herd outbreak. These results suggest that the modified-live vaccine should only be administered to non-gestating sows.  相似文献   
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