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排序方式: 共有379条查询结果,搜索用时 156 毫秒
71.
Michael Coad Derek Clifford Shelley G. Rhodes R. Glyn Hewinson H. Martin Vordermeier Adam O. Whelan 《Veterinary research》2010,41(2)
The principal surveillance tool used to control bovine tuberculosis in cattle is the removal of animals that provide a positive response to the tuberculin skin-test. In this study we performed a longitudinal investigation of the immunological and diagnostic consequences of repeated short-interval skin-tests in cattle naturally infected with Mycobacterium bovis. Tuberculin skin-test positive cattle were subjected to up to four further intradermal comparative cervical skin-tests at approximately 60-day intervals. A significant progressive reduction in the strength of the skin-test was observed after successive tests. In contrast, the magnitude of interferon-γ (IFN-γ) responses was not influenced by repeat skin-testing either transiently around the time of each skin-test or longitudinally following repeated tests. A significant boost in blood interleukin-10 (IL-10) production was observed within 3 days following each skin-test although the magnitude of this boosted response returned to lower levels by day 10 post-test. The application of a novel multiplex assay to simultaneously measure seven cytokines and chemokines also identified that skin-testing resulted in a significant and progressive reduction in antigen specific interleukin-1β (IL-1β) whilst confirming stable IFN-γ and elevated IL-10 responses in the blood. Therefore, we have demonstrated that in cattle naturally infected with M. bovis, repeat short-interval skin-testing can lead to a progressive reduction in skin-test responsiveness which has potential negative consequences for the detection of infected animals with marginal or inconclusive skin-test responses. The desensitising effect is associated with decreased IL-1β and elevated IL-10 responses, but importantly, does not influence antigen specific IFN-γ responses. 相似文献
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Danielle E. Berube DVM ; Megan F. Whelan DVM DACVECC ; Kathy C. Tater DVM DACVD Kiko E. Bracker DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2010,20(1):148-154
Objective – To describe the clinical course of a cat diagnosed with Fournier's gangrene.
Case Summary – A 2-year-old castrated male cat was presented to an emergency hospital for evaluation of acute onset of lethargy, mucoid anal discharge, and fever. During hospitalization, with provision of supportive care, an area of necrotizing fasciitis around the prepuce and anus developed and surgical debridement was performed. Severe sepsis developed secondary to the necrotizing fasciitis and the cat was eventually euthanized.
New Information Provided – The purpose of this report is to document the first case of Fournier's gangrene in a cat that presented for mucoid anal discharge, lethargy, and mild ataxia, and to alert emergency clinicians to this disease process. Early detection of the disease with prompt, aggressive supportive care and surgical debridement is necessary for successful treatment. 相似文献
Case Summary – A 2-year-old castrated male cat was presented to an emergency hospital for evaluation of acute onset of lethargy, mucoid anal discharge, and fever. During hospitalization, with provision of supportive care, an area of necrotizing fasciitis around the prepuce and anus developed and surgical debridement was performed. Severe sepsis developed secondary to the necrotizing fasciitis and the cat was eventually euthanized.
New Information Provided – The purpose of this report is to document the first case of Fournier's gangrene in a cat that presented for mucoid anal discharge, lethargy, and mild ataxia, and to alert emergency clinicians to this disease process. Early detection of the disease with prompt, aggressive supportive care and surgical debridement is necessary for successful treatment. 相似文献
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K. McNamara P. O'Kiely J. Whelan P. D. Forristal H. Fuller J. J. Lenehan 《国际虫害防治杂志》2013,59(3):167-172
The scale of damage caused by vertebrates to the plastic wrap on baled silage was evaluated on Irish farms. A survey was conducted on 300 farms representative of farming systems and geographical locations throughout Ireland. The scale of damage was classified as farms with 0%, 1-10%, 11-50% or 51-100% of bales with holes in the plastic wrap caused by birds. The proportion of farms within these four classes with damage caused by birds during the short interval between wrapping and removal from the field to storage was 47%, 37%, 15% and 1% of the total, respectively. Correspondingly, during the subsequent storage prior to feedout, bird damage was 37%, 50%, 12%, and 1%. Similarly, the proportions for damage throughout long-term storage due to cats were 71%, 23%, 6% and 0%, while the incidence of damage caused by rats, dogs and farm livestock was comparatively small. The stored bales were fenced against livestock on 86% of farms, while netting, bale painting and other protection methods were used to discourage damage on 2%, 17% and 9% of farms, respectively. The damage caused by birds was more prevalent on farms where the bales were stored on their curved side rather than their flat end, more than twotiers high and in farmyards rather than in fields. Cats damaged the sides and shoulders of the peripheral bales within bale collections, particularly where wrapped bales were stored in the farmyard. 相似文献
77.
为加强冬青属Ilex植物资源的保护和利用,采用标准样方法调查分析了浙江宁波天童4种冬青种群结构及更新类型。结果表明:1所调查群落共出现木本植物61种,除草本层外,林木层由下至上可分为灌木层和乔木层,其中在乔木层之上存在分别由小果冬青Ilex micrococca,马尾松Pinus massoniana,天童锐角槭Acer acutum构成的不连续的超高层。2所调查冬青属植物的年龄结构可分为4种类型:增长型(皱柄冬青Ilex kengii),稳定型(铁冬青Ilex rotunda),成熟型(冬青Ilex chinensis)和衰退型(小果冬青Ilex micrococca)。3冬青属植物总体生长良好,但有些种如小果冬青属于衰退型,无幼苗,无萌枝,种子更新困难,冬青幼苗难以通过环境筛导致幼树严重匮乏,需要采取适当人工育种以及栽培技术来加以繁殖保护,并对优良种质加以选育和利用。 相似文献
78.
Daniela Basso FACCO Edicarla TRENTIN Gerson Laerson DRESCHER Rodrigo Knevitz HAMMERSCHMITT Carlos Alberto CERETTA Leandro Souza DA SILVA Gustavo BRUNETTO Paulo Ademar Avelar FERREIRA 《土壤圈》2023,33(3):496-507
Copper(Cu)-based fungicide application to control foliar diseases in grapevine(Vitis vinifera L.) can increase soil Cu availability. Brazilian soils have high natural Cu and manganese(Mn) concentrations, increasing the potential for toxicity to grapevine plants. Application of amendment substances can reduce the concentrations of toxic chemical species of Cu and Mn in soil solution, especially for the soils grown with young plants. We evaluated the chemical speciation of Cu and Mn in soil soluti... 相似文献
79.
P. A. Massey R. E. Creamer R. P. O. Schulte M. J. Whelan K. Ritz 《Biology and Fertility of Soils》2013,49(8):1189-1201
The application of phosphorus (P)-based fertiliser to agricultural soils can result in a skewed vertical distribution of P down the soil profile, since the element tends to accumulate at the soil surface. Such accumulation can have detrimental effects on the environment, as the erosion of surface soil can facilitate the transfer of large quantities of P out of the field into water bodies. Earthworm and plant communities are intricately linked to vertical nutrient distributions in soil, with both communities either facilitating or negating the incorporation of nutrients into the soil matrix. This study aimed to investigate the effect of earthworm presence, plant community structure and fertiliser type to affect the distribution of nutrients in experimental mesocosms; with particular emphasis on the vertical distribution of P. Mesocosms were designed to simulate a soil which has a high P concentration at the surface compared to further down the soil profile. It was hypothesised that the presence of earthworms would facilitate the incorporation of P into the soil matrix and the presence of a more botanically diversity community would assimilate a greater quantity of soil nutrients. After 1 year, mesocosms were deconstructed into five depth ranges, and the distribution of nutrients were modelled and analysed. Results indicated that the presence of earthworms did redistribute soil nutrients from the surface into the matrix beneath. This redistribution was apparent from a reduction in nutrient concentrations in the 0–1 cm depth range. The presence of a more botanically diverse community not only assimilated greater soil nutrient concentrations, but also promoted a less even vertical distribution of soil nutrients, demonstrating the importance of soil biota and plant diversity in the redistribution of soil nutrients. 相似文献
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