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Cynthia M. Otto DVM PhD DACVECC 《Journal of Veterinary Emergency and Critical Care》2007,17(4):359-367
Objective: To provide evidence that naturally occurring sepsis in dogs provides a unique opportunity to test new therapies in clinically relevant settings. Data sources: Human and veterinary literature. Human data synthesis: Sepsis is a devastating condition responsible for most intensive care unit deaths. Most clinical trials targeting inflammatory mediators of sepsis have failed to improve outcome in clinical patients despite promising results in laboratory animal models. Animal models of sepsis fail to reproduce the clinical syndrome and therefore lead to conclusions that may not be relevant to clinical care. Veterinary data synthesis: Sepsis is recognized but not well‐characterized in companion animal species. Despite some species variability, the cardiopulmonary response to sepsis in dogs is similar to humans. Additionally, inflammatory and coagulation changes that accompany canine sepsis are consistent with those documented in humans. Sepsis secondary to canine parvoviral infection offers the advantages of relative population homogeneity, predictable course, and easy early diagnosis. The disadvantages of canine parvovirus are that it affects a predominantly young and healthy population and results in low mortality with aggressive supportive care. Septic peritonitis and pneumonia have high mortality but can be challenging to diagnose, have a variable course, and affect a heterogeneous population, which can be an advantage or a disadvantage. Conclusions: Similar to trials currently being performed in canine cancer patients, veterinary clinical trials of new sepsis therapeutics may provide a unique opportunity to advance the treatment of sepsis in dogs, humans, and other species. Spontaneous sepsis from canine parvovirus, peritonitis, and pneumonia are common clinical conditions in which therapeutics can be tested. 相似文献
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随着植物源农药的发展,具有优良农用活性的禾本科植物香根草Vetiveria zizanioides (L.) Nash越来越受到重视。文章首先介绍了香根草中挥发性成分的提取分离方法及结构鉴定,列举了其主要挥发物的结构;进而综述了其对二化螟 Chilo suppressalis (Walker) 等螟蛾科害虫的引诱作用、家白蚁Coptotermes formosanus Shiraki 等白蚁的驱避及拒食作用、对蚬木曲脉木虱Macrotermes barneyi Light等的毒杀作用,对水稻纹枯病菌Rhizoctorzia solani、香蕉炭疽病菌Calletotrichum musae等多种真菌和金黄色葡萄球菌Staphylococcus aureus Rosenbach 等多种细菌的抑菌活性,以及对藜Chenopodium album L.、豚草Ambrosia artemisiifolia L.等常见杂草的除草活性等;最后总结了香根草中活性化合物诺卡酮的化学及生物合成方法。可为进一步将香根草应用于植物源农药研究和开发利用提供参考。 相似文献
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样品采集是兽医科学研究中必不可少的环节。以中华人民共和国农业行业标准《动物疫病实验室检验采样方法》为基础,结合临床实践和研究经历,介绍了基于不同研究目的和内容的样品采集种类、数量和操作,以及样品收装、保存和处理方法,重点概述了国内外关于采样方法的最新进展,从而为今后的兽医科学研究提供参考。 相似文献
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水泵作为一种通用机械,应用广泛,除用于抽水外,还可用来抽送酸碱盐溶液或固体粒块的浆状物。由于工作环境差,大大缩短了水泵的使用寿命。通过对农用泵使用情况的跟踪调查,发现泵中轴承损坏是导致水泵寿命缩短的关键。另外,由于泵的轴承所使用材料单一,不可能完全承受泵的上述工作条件,是造成轴承破(磨)损的主要原因。为此,以一种塑铜合金塑料(聚四氟乙烯加青铜粉)为材料,利用冷压烧结成型法,研制出了塑铜合金水泵轴承。经大量试验研究证明:该材料提高了水泵轴承抗拉、抗压和抗弯强度,增加了硬度,摩擦系数小,承载能力强,导热系数大,润滑性能好,使用寿命长达1500h,完全可以推广应用。 相似文献
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Demand for urban allotment plots has recently increased in Portugal but little is known about the characteristics and motivations of the demanding population, and if and how its characteristics affect its motivations.In this article, we use the Municipal Network of Urban Allotment Gardens (MNUAG)1 launched by the Portuguese municipality of Vila Nova de Gaia for an exploratory Case Study research. Based on the data collected in the MNUAG application forms submitted in the period 2012–2013, we describe the characteristics and the motivations of the population demanding for urban allotment gardens (UAG)2 and run a logit model to find if and how the motivations are influenced by the characteristics.The population of applicants to the MNUAG is quite diverse. It has a balanced gender distribution and an average age of 47 years. Most of the applicants are between 25 and 64 years old, and belong to households with 2–4 members.To supplement family budget, occupation of leisure times, and access to organic farming are its most important motivations, followed by environmental concerns, the practice of physical exercise, and education.Motivations are influenced by the characteristics. This study has identified two groups of applicants with contrasting motivations. Food security is the only significant motivation for the unemployed and low-income applicants. Food safety, health concerns, environmental concerns, recreation, and education are common and frequent motivations among the upper and intermediate professional groups.Results can have future implications on the MNUAG, namely on the UAG location and typology, plot number, and plot size. To meet the demand of all the types of applicants, while fostering social cohesion, the municipality should reinforce its current small UAG structure and add to the MNUAG one or two productive parks. 相似文献
100.
二化螟是我国水稻的重要钻蛀性害虫,常年发生危害严重,给水稻生产带来巨大产量损失。寄生蜂是二化螟重要的生态调节因子和生物防控天敌资源,对田间二化螟的种群数量具有明显的自然控制作用。本文主要就二化螟寄生蜂多样性及其影响因素、二化螟卵寄生蜂和幼虫寄生蜂生态控害功能及优势种利用、二化螟幼虫越冬滞育期间寄生蜂对越冬幼虫种群基数的控制和寄生蜂生态控害功能的评估等方面的研究与应用进行综述,并探讨寄生蜂对二化螟生态控害功能的评估,尝试提出二化螟寄生蜂生态控害功能研究应在越冬代重视二化螟盘绒茧蜂、稻螟小腹茧蜂和中华钝唇姬蜂对越冬滞育幼虫的生态控害潜力、非越冬世代则重点发掘稻螟赤眼蜂、螟黄赤眼蜂和玉米螟赤眼蜂等卵期优势寄生蜂以降低田间二化螟卵的孵化率、减轻二化螟幼虫为害率,以期为提升寄生蜂的生态控害功能提供参考。 相似文献