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Summary

An equine model of acute non‐immune inflammation has been developed to facilitate studies of the inflammatory process and the actions of novel anti‐inflammatory drugs. Five polyester sponge strips soaked in sterile 2% carrageenin solution were placed in subcutaneous pouches prepared under local anaesthesia in the necks of conscious ponies. Serial removal of the strips and harvesting of the exudate enabled studies to be made of the cellular, biochemical and mediator aspects of the localised, acute inflammation, and the heat generated by the lesion was monitored by infra‐red thermometry. Maximal concentrations of the eicosanoids 6‐keto‐prostaglandin F, thromboxane B2 and leukotriene B, occurred at 9 h, whereas leukocyte numbers, lactate dehydrogenase (LDH) and total protein concentrations were greatest at 24 h. Lesional skin temperature was increased by approximately 4°C throughout the 24 h period. The novel anti‐inflammatory agent BW540C, administered orally at a dose‐rate of 20 mg/kg, did not affect leukocyte infiltration or the concentrations of protein, LDH and eicosanoids in exudate but serum thromboxane B2 levels were reduced. Skin temperature rises were greater in drug‐treated animals.

It is concluded that higher doses of BW540C will be required for a clinically useful anti‐inflammatory action in horses.  相似文献   
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"三江源"有"中华水塔"之称,是世界高海拔区生物多样性最丰富、最集中的地区之一.近年来由于自然气候变化、人类的过度利用和鼠害的爆发,使得该地区草地生态系统严重受损,生态服务功能逐渐降低.如何通过监测手段掌握该地区鼠害的危害区域、危害的等级从而作出判断已成为亟待解决的问题,为此,通过运用"3S"技术与地面调查相结合,对地面数据和空间数据进行处理和分析,确定主要的模型因子并构建监测模型,对鼠害退化草原进行遥感监测的技术路线.  相似文献   
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Although considerable conservation resources have been committed to develop and use law enforcement monitoring and management tools such as SMART, measures of success are ill‐defined and, to date, few reports detail results post‐implementation. Here, we present 4 case studies from protected areas with Amur tigers (Panthera tigris altaica) in Russia, in which indicators of success were defined and evaluated at each. The ultimate goal was an increase in tiger numbers to 1 individual/100 km2 at each site. We predicted that improvements in law enforcement effectiveness would be followed by increases in prey numbers and, subsequently, tiger numbers. We used short‐term and long‐term indicators of success, including: (i) patrol team effort and effectiveness; (ii) catch per unit effort indicators (to measure reductions in threats); and (iii) changes in target species numbers. In addition to implementing a monitoring system, we focused on improving law enforcement management using an adaptive management process. Over 4 years, we noted clear increases in patrol effort and a partial reduction in threats. Although we did not detect clear trends in ungulate numbers, tiger populations remained stable or increased, suggesting that poaching of tigers may be more limiting than prey depletion. Increased effectiveness is needed before a clear reduction in threats can be noted, and more time is needed before detecting responses in target populations. Nonetheless, delineation of concrete goals and indicators of success provide a means of evaluating progress and weaknesses. Such monitoring should be a central component of law enforcement strategies for protected areas.  相似文献   
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Reason for performing study: Accumulations of tracheal mucus assessed by endoscopic examination are associated with poor performance in racehorses. The air quality in horses' stalls may contribute to this visible tracheal mucus. Objectives: To determine whether the concentration and number of airborne particulates in stalls are associated with visible accumulations of tracheal mucus and with the number of inflammatory cells in tracheal aspirates. Methods: We studied 107 racehorses from 3 stables, in 3 different months, and measured airborne particulate matter 3 times daily in each of the stalls. On each monthly visit, horse airways were examined endoscopically and assigned a mucus score, and tracheal lavage was performed. Bivariate procedures, general estimating equations and linear mixed models were applied to estimate the association between PM and the presence of accumulations of mucus and number of inflammatory cells. Results: Stable, stall, month and PM were all significantly associated with the presence of accumulations of tracheal mucus, which had an overall prevalence of 67%. The odds of horses having visible accumulation of mucus were increased when horses occupied enclosed stables or stalls with higher particulate concentrations, and when concentrations of larger particles (≤10 µm in diameter) were elevated. Sixty‐eight percent of tracheal wash samples contained more than 20% neutrophils. Increased numbers of neutrophils were associated with the concentration of smaller particles (≤2.5 µm in diameter). Potential relevance: Careful consideration of stable construction and management practices focused on maintaining the lowest possible dust concentrations throughout the day should reduce the prevalence of visible accumulations of tracheal mucus, potentially improving racing performance.  相似文献   
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灰色系统理论在燕麦抗倒伏综合评价中的应用   总被引:5,自引:0,他引:5  
刘刚  赵桂琴 《草业科学》2006,23(10):23-27
运用灰色系统理论中的灰色关联度法对20个燕麦Avena sativa品种(系)的抗倒伏性进行综合评价,同时利用综合评价值与各指标进行最优回归方程模型的拟合。结果表明,青永久343的综合评价值最高,抗倒伏性最好;甘肃黄燕麦的综合评价值最低,最易倒伏,这与燕麦田间倒伏调查结果基本吻合。各指标中穗长倒数、株高构成指数、弹力和2~3茎节鲜质量4个指标对燕麦抗倒伏性有显著影响。  相似文献   
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计算机视觉是人工智能的重要发展方向,可以显著改善人与世界的交互方式,加强计算机视觉技术在智能养猪中的研究和应用必将为养猪业带来一场变革。本文综述了计算机视觉技术在猪只识别、行为监测、体尺测量、体重估测、肉品质评定、疾病监测等方面的研究进展,以期促进我国养猪业的智能化发展。  相似文献   
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