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11.
The experiment was performed to evaluate the ameliorative effect of ascorbic acid (AA) on some hematological parameters and erythrocyte osmotic fragility (EOF) in horses transported by road. A total of 14 horses, consisting of seven experimental and seven control horses, were used for the experiment. Before the transportation, blood samples were obtained by jugular venipuncture from all the horses. Experimental horses were administered with AA (200 mg/kg dissolved in 20 mL of distilled water per os), whereas the control horses were given 20 mL of distilled water per os. Thereafter, the animals were transported for 6 hours and blood samples collected after transportation. Packed cell volume and hemoglobin concentration were higher (P < .05) in experimental than the control group, whereas total leukocytes reduced significantly (P < .05) in experimental in comparison with the control horses. Lymphocyte, neutrophil counts, neutrophil/lymphocyte ratio, and total protein decreased in experimental horses in comparison with control, but they were not significant (P > .05). Erythrocyte osmotic fragility was lower in experimental than the control at 0.3% NaCl concentration (P < .05). The result of the present study revealed that AA ameliorated changes in hematological parameters and EOF induced by road transport stress, partly because of its antioxidant properties.  相似文献   
12.
Recent investigations by the Australian Department of Agriculture, Fisheries and Forestry into high mortalities on live export voyages from Australia to the Middle East during the Northern hemisphere summer suggest that animal welfare may be compromised by heat stress. The live export industry has generated a computer model that aims to assess the risk of heat stress and to contain mortality levels on live export ships below certain arbitrary limits. Although the model must be complied with under Australian law, it is not currently available for independent scientific scrutiny, and there is concern that model and the mandated space allowances are inadequate. This review appraises the relevant literature on heat stress in sheep and cattle, including laboratory studies aimed at mimicking the ambient temperatures and humidity levels likely to be encountered on live export voyages. Animal welfare is likely to be very poor as a result of heat stress in some shipments.  相似文献   
13.
Embryonated eggs of theEuropean native white-clawed crayfish Austropotamobius pallipes Lereboullet weresubjected to three periods of storage usingpolystyrene boxes and, afterwards, artificiallyincubated. At the end of the longest storage(42 days) survival rate was 98.3%, with 65%developed to stage 2 juvenile. Differentstorage periods allowed the staggeredproduction of juvenile batches within a monthperiod. The same containers used for storagewere also suitable for transport.  相似文献   
14.
农药在土壤中迁移及其影响因素的初步研究   总被引:14,自引:2,他引:14  
本文运用非饱和土壤中水分运动和溶质运移基本理论,建立了非饱和土壤中农药运移的数值模拟模型.模型中考虑了农药在土壤中迁移与转化的主要过程:附土壤水分的对流;水动力弥散;土壤吸附及生物化学降解等.模型得到了室内土柱中灭幼脲-Ⅲ号杀虫剂淋溶试验的验证.文中分析了各种因素对该农药存土壤中迁移的影响,并且对两种不同的农药进行了比较.研究表明,在本文所研究的条件下影响农药在土壤中迁移与转化的主要因素是土壤吸附和农药在土壤中的降解.  相似文献   
15.
淹水土壤中氮素运移与转化试验及其数值模拟   总被引:4,自引:0,他引:4  
在室内试验的基础上,建立了淹水土壤中NH4+—N和NO3-运移转化的耦合数学模型,并对表施于水层中的氮肥(碳铵:NH4HCO3)在饱和土中运移与转化过程进行了数值模拟。结果表明:该试验条件下NH4+—N的硝化作用主要发生于土壤表层1cm左右的范围内。  相似文献   
16.
Summary Vertical translocation of the introduced transposon Tn5-tagged Pseudomonas fluorescens cells was studies after irrigation of 50-cm long soil columns of loamy sand. The soil in the columns was slowly brought to saturation using groundwater, and enough water was then slowly added to permit collection of the percolated water. Introduced bacteria were transported to lower soil layers to a significantly higher degree in undisturbed soil cores than in repacked cores; water transport was hampered in both core types due to high soil bulk densities. Soil bulk density affected the degree of transport of the introduced cells; progressively more cells were translocated to deeper soil layers and into the percolation water at decreasing soil bulk densities. Repeated percolation of soil at a bulk density of 1.25 caused an increase in Tn5-tagged cell numbers in the lower soil layers and in the percolated water. Further, cells initially introduced into a dry (5.3% moisture) soil were translocated to a lesser extent than cells introduced into a wetter (13% moisture) soil. Finally, wheat roots enhanced the water-induced transport of introduced cells to the 40- and 50-cm deep soil layers and into the effluent, but not to the remaining soil layers. Large soil columns such as those used in the present study are useful in assessing the transport and survival of introduced bacterial cells in soils under a variety of simulated environmental conditions.  相似文献   
17.
随着土壤溶质运移理论研究的发展及人们对氮肥施用引起的环境问题的日益关注,国内外学者对氮素运移、转化机理的研究也不断深入。在此,对国内外氮素运移、转化规律及模拟模型研究的现状作了介绍,并简要讨论了该领域未来的研究趋势和发展方向。  相似文献   
18.
Expression and Localization of HSPs in the Liver of Transported Pigs   总被引:1,自引:0,他引:1  
To demonstrate the distribution and expression of heat shock proteins (HSPs) in the liver, five kinds of HSPs, namely HSP70 , HSP72, HSP86, HSP90 and HSP27 were determined after a long distance transport using immunohistochemistry and Western blot. All five HSPs were regularly detected in the liver of both the transported and the control group. Both nuclear and cytoplasmic labeling was present in hepatic cells;however, localization of HSPs was quite different in hepatocytes. The majority of HSP70, HSP72 and HSP27appeared to predominate in cytoplasm of the hepatocytes. Nuclear signals of HSP90 and HSP86 were most prominent in hepatocytes in which immunostaining in the cytoplasm was relatively weak compared with that in the nucleus. There was subjectively lower staining in the edge of hepatic labule, and lower numbers of HSPs labeled hepatic cells corresponded to light microscopic lesions. The obvious inductions of some HSPs were detected in the liver, especially the HSP90(P< 0.01) which belongs to the HSP90 family. However, the obvious reductions of HSP86 (P < 0.05), which belong to the HSP90 family, and HSP27 ( P < 0.05), which belong to small families, were detected in stressed pig liver after six hours of long distance transportation.  相似文献   
19.
甘蓝型油菜不同品种磷运转和再利用差异的研究   总被引:7,自引:0,他引:7  
采用土壤盆栽试验定量测定并计算4个有代表性的甘蓝型油菜品种(97029、97073、97081、97105)在苗期、蕾期、花期、结角期和成熟期的磷运转和再利用情况,以期揭示磷高效的营养机制。结果表明,所有参试品种在磷的运转和再分配方面都体现了“顶端优势”,磷向生长中心运转和再分配最为活跃,但不同品种在不同生育时期存在明显的阶段性差异。苗期缺磷对地上部的影响比对地下部大,磷高效品种97081苗期和蕾期根系具有较强的磷吸收能力,磷累积量大,但输出率较小,对磷的再利用程度较小;花期耐低磷的适应性反应转为增强再利用,养分开始向生长中心运转;结角期叶片贮备养分比例较大,生长后劲足;成熟期养分向生长中心转移彻底,使有限的磷发挥了最大效能。  相似文献   
20.
芜菁花叶病毒在油菜不同生育阶段的侵染性有很大差异,以苗期最易被侵染,而成株期抗侵染能力很强。随着植株生育进程,病毒含量由低到高,并分布于各器官。病毒的增殖和运转与植株体内营养物质的积累和运输密切相关。病毒在植株体内的垂直分布情况,随着植株的生长发育,病毒有由下向上输送的趋势。根据病毒的侵染、增殖和运转规律,对防治工作有一定指导意义。  相似文献   
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