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41.
Counts of Salmonella were performed by the most probable number technique on 16 articles of abattoir equipment having direct contact with the carcase. Forty samples were collected from each article over 21 months. The contamination rate of these articles with salmonellae varied from nil % for a saw used to quarter the sides to 47.5% for stainless steel tables and hooks. Mesh gloves were also highly contaminated, salmonellae being isolated from 32.5% of gloves on the slaughter floor and 40% of those in the boning room. Salmonella counts ranged from 1.0 to 3,663 organisms per article. Mesh gloves, cutting boards and stainless steel tables were found to have counts that were at times greater than 1,000 salmonellae per article.  相似文献   
42.
A review is given of work on the movement of solutes into sieve elements, particularly with regard to investigations in which sieve tube exudate is obtained via the severed stylets of the aphid Tuberolachnus salignus (Gmelin), sited on bark strips or stem segments of willow. Evidence is given showing that the uptake of naturally occurring solutes is an active and highly selective process, thus the rate of uptake is governed not by differences in concentration between the sieve tube and the source cells, but by “potential” gradients. It is pointed out that the phenomenon of selectivity by the sieve tube cannot yet be explained, though experiments are described which indicate the site of selection to be the tonoplast of the source cells, at least in the case of sugars. Calcium is generally considered to be a rather phloem-immobile cation. Evidence is given which demonstrates that a factor determining the immobility of this substance may be its inability to enter the sieve elements. Some data are provided on the movement of certain synthetic growth regulators and herbicides into the sieve elements of willow. These were found to be loaded within a short time from their application to the cambial surface of bark strip. It is suggested that their ability to move into sieve elements is brought about by competition with naturally occurring solutes. The conclusion is reached that investigations on solute loading are probably of more practical importance than those on the mechanism of longitudinal transport, since the control of the overall rate of transport may be in the former, rather than the latter, process.  相似文献   
43.
Atopic dermatitis (AD) is very common in dogs, but its pathogenesis is not yet fully understood. It has been suggested that a Th2-dominant status may be associated with the occurrence of canine AD. IL-12 is thought to be important for the differentiation of Th1 cells. The IL-12 receptor β2 (IL-12Rβ2) gene is considered to play a critical role in signal transduction and is attracting attention as one of the causative genes of AD in humans. The purpose of this study was to investigate the relationship between IL-12Rβ2 gene expression and canine AD. The canine IL-12Rβ2 gene was cloned by RT-PCR and its nucleotide sequences were determined. Canine IL-12Rβ2 showed 76.8% homology at the amino acid level with human IL-12Rβ2, and its structural motifs were well conserved. cDNA with a 91 bp deletion including the transmembrane region was also cloned, which consequently produced a frame shift and an early stop codon. The deletion region corresponded to exon 14 of the human IL-12Rβ2 gene on chromosome 1. The expression of deleted canine IL-12Rβ2 mRNA in phytohemagglutinin-stimulated peripheral blood mononuclear cells was examined in seven healthy dogs and 11 AD dogs. Both deleted and intact mRNAs were expressed at constant ratios in healthy and AD dogs. The results indicate that the deletion of the transmembrane region is not associated with the occurrence of AD, and that the expression of the deleted mRNA may be constitutive and produced by alternative splicing.
Funding: Self-funded.  相似文献   
44.
The in vivo effects of a single prophylactic dose of recombinant bovine interferon (rBoIFN)-alpha I1 in calves with salmonellosis were investigated, using a Salmonella typhimurium infection model. Treatment with rBoIFN-alpha I1 reduced the degree of septicemia compared with that in control groups, and, in one experiment, using disease of reduced severity, body temperature was lower in treated calves than in controls.  相似文献   
45.
Holistic Planned Grazing? (HPG) is purported to have positive long-term effects on rangelands, enhancing ecosystem services. Given comparable environmental templates, but different management regimes, vegetation monitoring and landscape function analysis showed the Africa Center for Holistic Management (ACHM) at Dimbangombe had a significantly higher rangeland condition (composition, cover, standing crop and soil health) than adjacent Sizinda (SCR) and Monde (MCR) communal rangelands. Overall grazer density on ACHM is 42% higher than that of SCR (no data for MCR). Finer-scale satellite collar data for ACHM yielded a calculated stocking rate of 0,55 LSU ha-1 y-1 or 24 590 kg km-2, which constitutes high-density grazing. An energy flow estimate shows that the grazing resource would, on average, not be limiting for livestock on ACHM but limiting on SCR. HPG may include an element where kraals are inserted into degraded rangelands for a short period. Overall, ACHM shows stable perennial composition with smaller tufts significantly closer together. A similar result was visible in SCR where maize yields were visibly higher on kraaled areas than on adjacent untreated fields. HPG yields positive long-term effects on ecosystem services (soils and vegetation) and points to the HPG approach enhancing the sustainability of livestock and wildlife in this environment.  相似文献   
46.
Canine atopic dermatitis (cAD) is a common disease with a multifactorial aetiology associated with impaired immunoregulation. The immunopathogenesis has similarities to that of human atopic dermatitis. Clinical signs of allergic disease in humans and mice are reduced by administration of saprophytic mycobacteria that amplify regulatory cytokines and hence the effect of Mycobacterium vaccae on the clinical severity of cAD was investigated. Sixty-two dogs with cAD, selected according to strict criteria, were treated with a single intradermal injection and evaluated monthly for 3 months in a placebo-controlled double-blind clinical trial. Clinical severity was quantified using standardized scores and by owner assessment of pruritus. A single injection of a heat-killed suspension of M. vaccae was found to be well tolerated and effective in treating mild to moderate cases of cAD demonstrable for 3 months, but was insignificant in more severely affected dogs.  相似文献   
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