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41.
Bovine respiratory syncytial virus (BRSV), a member of the subfamily Pneumovirinae, family Paramyxoviridae, is a major cause of respiratory disorders in young cattle. A number of studies were conducted to validate a reliable animal model for the infection, since BRSV inoculation on the natural host is costly and often unsuccessful. Unfortunately, after inoculation of BRSV in Balb/C mice, viral replication may be detected; however, evident pathological alterations are absent on the experimentally infected animals. In order to establish a mice model that could be used further for preliminary studies of pathological and immunological aspects of BRSV infection, three mice inbred lineages (Balb/C, A/J and C57BL6), possessing different genetic backgrounds, were tested about its susceptibility to the inoculation with BRSV. Animals were inoculated through the nasal and ocular routes and were observed after inoculation. At 7 days post-inoculation (dpi) animals were necropsied and virological (virus isolation and viral nucleic acid amplification) as well as histopathological examinations were performed. A/J and C57BL6 showed interstitial pneumonia, when compared to the Balb/C group. These findings shows that mice may constitute a suitable model for the study of BRSV infections, depending on the mice strain used for experimental inoculations.  相似文献   
42.
As acid deposition declines, recovery from acidification is delayed by the fact that the soil processes that earlier buffered against acidification are now being reversed. Monitoring of within catchment processes is thus desirable. However, soil sampling is destructive and not suitable for long-term monitoring at a single site, whereas sampling of soil water with suction lysimeters may be more suitable. In this paper we evaluate 8–11 years of soil water chemistry from E- and B-horizons in three acid forest soil plots within monitored catchments. Five years of sampling also included the C-horizon. To our knowledge, this is the first long-term lysimeter study including the E-horizon showing recovery from acidification, and one of few studies including the B-horizon. Soil water concentrations of SO4 decreased significantly between –9.5 and –1.4 μeq L-1 yr-1, with much higher rates of change at two southern sites compared to a northern site, where levels and changes of deposition were lower. The average annual bulk deposition of S ranged between 3 kg S ha-1 at the northernmost site to 11 kg S ha-1 at the southernmost site. The SO4 decline in E-horizons was smaller than the decline in deposition, which indicated leaching of SO4 from the O-horizon. At the two southern sites, a weaker decline in SO4 in the B-horizon compared to the E-horizon indicated desorption of SO4. The negative trends in SO4 were to a large extent balanced by decreases in base cations but there were also tendencies of recovery from acidification in soil solution at the southern sites by increasing pH and ANC. However, these were contradicted by increasing Al concentrations. A high influence of marine salts in the early 1990s may have delayed the recovery. Decreasing trends of the Ca/(H+)2 ratio in the soil solution, most pronounced at one of the southern sites, suggested that the soils were becoming more acidic, although the soil solution tended to recover.  相似文献   
43.

Background

The process for obtaining monoclonal antibodies against a specific antigen is very laborious, involves sophisticated technologies and it is not available in most research laboratories. Considering that most cytokines remain partially conserved among species during evolution, the search for antibody cross-reactivity is an important strategy for immunological studies in veterinary medicine. In this context, the amino acid sequence from human and canine cytokines have demonstrated 49–96 % homology, suggesting high probability of cross-reactivity amongst monoclonal antibodies. For this, 17 commercially available anti-human monoclonal antibodies [IL-1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8 (#1, #2), IL-10, IL-12, IL-13, IL-17A, IFN-γ (#1, #2), TNF-α (#1, #2) and TGF-β], were evaluated in vitro for intracellular cytokine detection in a stimulated canine blood culture by flow cytometry and confocal microscopy. Lymphocytes from peripheral blood of healthy and two unhealthy dogs were analyzed.

Results

Eleven anti-human mAbs [IL-1α, IL-4, IL-5, IL-6, IL-8 (#1, #2), IL-12, IL-17A, TNF-α (#1, #2) and TGF-β] cross-reacted against canine intracellular cytokines. The specificity of the assays was not affected after Fc-blocking. Three anti-human cytokine mAbs [IL-4, IL-8 (#2) and TGF-β] when evaluated by confocal microscopy also cross-reacted with intracellular canine cytokines. The identification of human mAbs that cross-reacted with canine cytokines may support their use as immunological biomarkers in veterinary medicine studies.

Conclusion

The identification of these 11 anti-human cytokine mAbs that cross-reacted with canine cytokines will be useful immunological biomarkers for pathological conditions by flow cytometry and fluorescence microscopy in dogs.  相似文献   
44.
The primary goal of this study was to propose saffron as a sustainable substitute crop with high added value in some Moroccan agricultural areas with low and erratic rainfalls, for their socio-economical development. The quality of the saffron spice has to be evaluated prior to recommendation for commercial production. For this purpose, saffron was grown in experimental plots for the first time in eleven different experimental zones with a disparity of altitudes, soils and climates. High-performance liquid chromatography (HPLC) was used to quantify the most important saffron components crocins, picrocrocin, and safranal which are respectively responsible for its colour, taste and odour. The respective average values, in % dry matter, across all sites altogether are 29.01 ± 5.6; 14.04 ± 7.1 and 0.22 ± 0.11. The statistical analysis shows that crocins are stable under each specific environment tested (p > 5%) for 3 years of study. Meanwhile, there was a large variability in safranal content for the same period (p < 0.05). This suggests that post-harvest processing of saffron produced under different environments may need to be improved. Analysis of environmental impact on saffron quality showed that just the altitude affects crocins (R2 = 0.84, p < 0.05).  相似文献   
45.
46.
J. Lage    R. M. Trethowan    E. Hernandez 《Plant Breeding》2008,127(4):350-354
Understanding the association among wheat growing locations allows plant breeders to better target crosses and identifies locations for germplasm exchange. To examine the relationship between yield testing sites in eight countries in western/central Asia, 291 data sets from CIMMYT's different international yield nurseries were combined into one analysis as no single nursery was well represented across the region; these nurseries represented wheat germplasm specifically developed for different agro-ecological zones including irrigated, semi-arid, high-rainfall, autumn- and spring-sown conditions. The shifted multiplicative model was used to group individual sites into clusters. Results revealed 18 site-by-site combinations as 'similar' to each other and 23 as 'contrasting' at a probability level of P < 15%. CIMMYT's main yield testing site in northern Mexico proved the best predictor for the region. Within the region two sites in Turkey and Iran were identified as possible sites for future regional testing. Overall the study showed that data from different yield nurseries can be combined to improve our understanding of site associations across western/central Asia to the benefit of both international and regional wheat breeders.  相似文献   
47.
Tomato yellow leaf curl virus (TYLCV) is one of the most widespread begomoviruses transmitted by the whitefly Bemisia tabaci that cause tomato yellow leaf curl virus diseases (TYLCDs). TYLCD losses can be especially severe in open‐field tomato (Solanum lycopersicum L.) crops. TYLCV is particularly well known and widespread in the Mediterranean (Med) countries where TYLCD control is mostly based on insecticidal control of B. tabaci populations. Unfortunately, Tunisian B. tabaci populations include Middle East‐Asia Minor I and the Med species that have developed resistance to many classes of insecticides. Therefore, TYLCD‐resistant cultivars are essential for sustainable disease management. Six TYLCD resistance genes (Ty) have been introgressed from wild species into cultivated tomato and are available for breeding. Information on the Ty genes or gene combinations is useful for breeding resistant cultivars. To this end, 14 tomato lines carrying different Ty gene combinations and two susceptible tomato entries were evaluated for TYLCD incidence and severity in two field trials during late season in Tunisia. Entries with Ty‐1/Ty‐3 + Ty‐2 offered the highest levels of resistance in Tunisia.  相似文献   
48.
Brucella abortus vaccines play a central role in bovine brucellosis control/eradication programs and have been successfully used worldwide for decades. Strain 19 and RB51 are the approved B. abortus vaccines strains most commonly used to protect cattle against infection and abortion. However, due to some drawbacks shown by these vaccines much effort has been undertaken for the development of new vaccines, safer and more effective, that could also be used in other susceptible species of animals. In this paper, we present a review of the main aspects of the vaccines that have been used in the brucellosis control over the years and the current research advances in the development of new B. abortus vaccines.  相似文献   
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