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61.
Design standards for experimental and field studies to evaluate diagnostic accuracy of tests for infectious diseases in aquatic animals 下载免费PDF全文
E Laurin K K Thakur I A Gardner P Hick N J G Moody M S J Crane I Ernst 《Journal of fish diseases》2018,41(5):729-749
Design and reporting quality of diagnostic accuracy studies (DAS) are important metrics for assessing utility of tests used in animal and human health. Following standards for designing DAS will assist in appropriate test selection for specific testing purposes and minimize the risk of reporting biased sensitivity and specificity estimates. To examine the benefits of recommending standards, design information from published DAS literature was assessed for 10 finfish, seven mollusc, nine crustacean and two amphibian diseases listed in the 2017 OIE Manual of Diagnostic Tests for Aquatic Animals. Of the 56 DAS identified, 41 were based on field testing, eight on experimental challenge studies and seven on both. Also, we adapted human and terrestrial‐animal standards and guidelines for DAS structure for use in aquatic animal diagnostic research. Through this process, we identified and addressed important metrics for consideration at the design phase: study purpose, targeted disease state, selection of appropriate samples and specimens, laboratory analytical methods, statistical methods and data interpretation. These recommended design standards for DAS are presented as a checklist including risk‐of‐failure points and actions to mitigate bias at each critical step. Adherence to standards when designing DAS will also facilitate future systematic review and meta‐analyses of DAS research literature. 相似文献
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为建立黎药海巴戟药材质量标准,为其质量控制及资源开发利用提供科学依据。依据《中国药典》2015 年版中药质量标准研制的要求,对药材性状、鉴别、检查、浸出物、含量测定等进行研究。明确了海巴戟药材性状和显微结构特征,并建立了其专属性薄层色谱鉴别方法;规定海巴戟药材多糖含量不得少于 6.0%、东莨菪内酯含量不得低于 0.017%、水分不得超过 10.0%、总灰分不得超过 6.0%以及醇溶性浸出物不得少于 20.0%。本研究制定的黎药海巴戟药材质量标准,可为该药材的质量控制提供依据。 相似文献
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通过对《地理标志产品六堡茶》标准与《六堡茶》标准在编写依据和方法、适用范围、术语和定义、分类、等级、要求、试验方法、检验规则等方面的对比,指出两标准的异同。结果显示,《地理标志产品六堡茶》是在《六堡茶》基础上增加六堡茶地理标志产品保护的内容制定而成,增加的内容主要有产品保护范围、原料种植的立地条件和气候条件、茶树品种、栽培技术、采摘、毛茶感官品质和理化指标等,产品等级从7个等级缩减至5个等级,前者比后者要求更宽广、更严格。《地理标志产品六堡茶》标准对保证六堡茶质量特色、提高质量水平,推动六堡茶产业持续健康发展具有引领作用。 相似文献
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Simon J. More Angus R. Cameron Matthias Greiner Richard S. Clifton-Hadley Sandra Correia Rodeia Douwe Bakker Mo D. Salman J. Michael Sharp Fabrizio De Massis Alicia Aranaz M. Beatrice Boniotti Alessandra Gaffuri Per Have Didier Verloo Michael Woodford Martin Wierup 《Preventive veterinary medicine》2009,90(3-4):254-267
Within the European Union (EU), detailed legislation has been developed for cattle, but not deer, to minimise disease risks associated with trade in animals and animal products. This legislation is expressed as input-based standards, providing a detailed outline of the activity required (for example, testing of animals and application of defined control measures), on the expectation that an adequate output (for example, confidence in freedom) will be achieved. Input-based standards are at odds with the increasing shift towards output-based standards, particularly in OIE rules governing international trade. In this paper, we define output-based standards to achieve and maintain freedom from tuberculosis (TB) in farmed deer, with reference to EU member states. After considering the probability of freedom achieved for cattle under existing EU legislation, we defined a ‘free farmed deer holding’ as one with a probability of freedom from infection of at least 99%. We then developed an epidemiological model of TB surveillance systems for deer holdings, incorporating different surveillance strategies, including combinations of diagnostic tests, and a variety of different scenarios relating to the potential for introduction of infection. A range of surveillance strategies were identified to achieve and maintain a free farmed deer holding, and worked examples are presented. The surveillance system sensitivity for varying combinations of screening and confirmatory tests in live animals, animals at slaughter and on-farm deaths is also presented. Using a single test at a single point in time, none of the TB tests routinely used in farmed deer is able to achieve an acceptable probability of TB freedom. If repeat testing were undertaken, an acceptable probability of TB freedom could be achieved, with differing combinations of the surveillance system sensitivity, frequency of testing and risk of introduction. The probability of introduction of infection through the importation of infected deer was influenced by the use of a pre-movement test (assumed 90% test sensitivity and negative test results), the TB prevalence in the source herd and the number of animals imported. A surveillance system sensitivity of at least 81% was achieved with different combinations of annual live animal surveillance and surveillance of animals at slaughter or on-farm deaths. This methodology has broad applicability and could also be extended to other diseases in both deer and other species with relevance to trade in animals and animal products. 相似文献
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北京市自2004年开始执行粮食直补政策,该政策对北京市的农业生产及农民的种植积极性产生重要影响。本文通过实地调研并结合北京市相关文件及统计年鉴数据,归纳了粮食直补政策在北京市的发展变化过程;分析了政策实施带来的初步成效,一方面提高了农民的纯收入,增加了种地收益产值,从而增强农民从事粮食生产的积极性,另一方面,粮食直补政策对北京市的种粮面积及粮食产量也有重要相关影响。同时指出目前粮食直补政策存在补贴标准不稳定,狭小的农业生产规模影响政策实施效果等问题。在此基础上,本文提出需坚持执行合理稳定具体的粮食直补政策,加强资金发放程序的监督管理,并设立合理的粮食规模经营标准,加大规模生产补贴力度等建议。 相似文献
67.
一种用于形成1kb阶梯DNA分子量标准载体的构建 总被引:2,自引:0,他引:2
构建了2个用于产生DNA分子量标准的载体pTLK3和pTLK5.pTLK3由1.0,2.0,4.0和5.0 kb 4个部分组成,经ApaI完全酶切后再用EcoRI部分酶切,可以得到1.0~8.0 kb以及12.0 kb的条带.pTLK5由3.0,0.5和1.5 kb 3个部分组成,用EcoRI完全酶切将得到3.0,0.5和1.5 kb 3种大小的片段.将pTLK3和pTLK5的酶切产物混合,得到1.0 kb阶梯的DNA分子量标准,其条带分别为0.5、1.0、1.5、2.0、3.0、4.0、5.0、6.0、7.0、8.0、12.0 kb的条带.此分子量标准适合0.5~8.0 kb的DNA的分子量测定.适用范围较广. 相似文献
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欧美发达国家场地土壤污染防治技术体系概述 总被引:7,自引:0,他引:7
国际经验表明,科学完整的土壤污染防治技术体系是全面推进土壤质量保护和土壤污染防治工作的基础保障,尤其对处于起步阶段且面临诸多挑战的中国土壤污染防治工作,虽然任重而道远,却是土壤污染管理能力建设的必然。为有效预防和治理修复工业遗留场地的土壤污染问题,加快推动城市土地的安全与可持续利用,本文全面系统地阐述了美国、英国和其他欧洲发达国家场地土壤污染防治技术体系的要素构成及演变特点:各国土壤污染防治制度及管理方法异同并存,构建一套完整有效的土壤污染防治体系必须以基于风险的全过程可持续管理为原则,涵盖法律保障、技术体系和管理手段等三个相互关联、相互影响的要素方面。其中,法律法规是标准制定和措施执行的核心原则和关键导向;标准导则是加强法律法规可行性的细化、具象;管理手段是法律法规和标准导则实践层面的配套保障。欧美等发达国家完善的场地土壤污染防治体系对中国防治体系的构建具有非常重要的指导意义,借鉴发达国家成功经验,从中国土壤污染防治的现实需要和具体国情出发,提出了三元一体的"法律—技术—管理"土壤污染防治技术体系的发展方向和重要内容,该体系涵盖法律法规体系、技术标准体系和可持续管理体系三个方面。 相似文献