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排序方式: 共有182条查询结果,搜索用时 15 毫秒
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E. R. Campagnolo M. E. Moll K. Tuhacek A. J. Simeone W. S. Miller K. O. Waller O. Simwale J. T. Rankin S. M. Ostroff 《Zoonoses and public health》2013,60(2):117-124
We report a fall 2010 cluster of pandemic influenza A/H1N1 (pH1N1) infections in pet ferrets in Lehigh Valley region of Pennsylvania. The ferrets were associated with one pet shop. The influenza cluster occurred during a period when the existing human surveillance systems had identified little to no pH1N1 in humans in the Lehigh Valley, and there were no routine influenza surveillance systems for exotic pets. The index case was a 2.5‐month‐old neutered male ferret that was presented to a veterinary clinic with severe influenza‐like illness (ILI). In response to laboratory notification of a positive influenza test result, and upon request from the Pennsylvania Department of Health (PADOH), the Pennsylvania Department of Agriculture (PDA) conducted an investigation to identify other ill ferrets and to identify the source and extent of infection. PDA notified the PADOH of the pH1N1 infection in the ferrets, leading to enhanced human surveillance and the detection of pH1N1 human infections in the surrounding community. Five additional ferrets with ILI linked to the pet shop were identified. This simultaneous outbreak of ferret and human pH1N1 demonstrates the important link between animal health and public health and highlights the potential use of veterinary clinics for sentinel surveillance of diseases shared between animals and humans. 相似文献
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在甘肃张掖大规模制种过程,采用人工调控土壤生态环境和田间调查方法,针对不同土体温度、湿度、酸碱度、养分含量,研究了菌丝体的生长状况和对寄主侵染的规律,提出了抗病品种为主的栽培措施以外的以调控土壤环境为主的防治方法。结果表明:致病菌枝顶头孢霉Acrrmonium strictum W.Gams在土壤pH7.0-8.0时生长迅速;生长适温为28~32℃,较菌丝体在培养基上的适温高;当绝对含水量在10%或20%时生长迅速;肥力因子N、K、P素对该病的影响较大,养分有效N素含量高、有效P素含量低、有效K含量不足发病重;病菌对幼苗的侵染也具明显的规律性,高温高湿有利于病菌对幼苗的侵染,病情指数增高,感病品种较抗病品种病情指数低。 相似文献
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Thoroughbred racehorses perform exercise at maximal intensities and typically display a hyperthermic exercise response, which can drive core body temperature to critical levels. Despite extremely efficient thermoregulatory mechanisms, certain weather conditions may affect the horse’s ability to cool and result in a syndrome referred to as exertional heat illness (EHI). This is characterised by central nervous system dysfunction, as well as cytotoxic effects of heat on cells, which can produce deleterious consequences. Early detection of exertional heat illness (EHI) in Thoroughbred racehorses can be difficult because signs are often vague and the measurement of rectal temperature as an indicator of hyperthermia is not practical. Best practice in the treatment of EHI in horses, as in human subjects, centres on early detection, rapid assessment and aggressive cooling. Research in human subjects has shown that EHI is manageable when recognised early and appropriate treatment provided. The aim of this study was to investigate the measurement of skin surface temperature (SST) by an infrared thermometer as an aid in the early detection of EHI. A skin surface temperature ≥39°C in the immediate postrace period is considered to be hot. It reflects the interaction of exercise-related metabolic heat production, physiological adjustments to the skin surface such as vasodilation and sweating, together with the effect of high ambient temperature. Most importantly, high SST is associated with a reduced core-to-skin temperature difference, which retards heat transfer from the deep body tissues to the skin and can hinder heat dissipation. Identification of horses with high SSTs can prioritise them for rapid cooling and curtail possible progression to EHI. 相似文献
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Severe equine asthma (SEA) syndrome is a chronic recurrent respiratory disease, common among adult horses. The disease occurs in genetically susceptible individuals after their exposure to organic dust. Thus, environmental management has proved essential in controlling airway challenge and disease exacerbation. This is a demanding process that can only be achieved through the horse owners’ cooperation. One year after initial diagnosis of SEA in a group of 39 horses, owner compliance to an environmental management protocol was evaluated. The overall compliance to the protocol was poor and the horses’ clinical health and need for pharmacological management was related to the successful implementation of the environmental recommendations provided on disease diagnosis. 相似文献
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抚顺“090621”冰雹多普勒雷达回波特征分析 总被引:2,自引:0,他引:2
利用常规气象资料和沈阳多普勒雷达资料,从天气背景、物理量和雷达回波演变特征分析了2009年6月21日抚顺东部地区出现冰雹天气过程的成因。结果表明:此次冰雹天气发生在地面低压带、500hPa冷涡底部东南象限中,500hPa冷涡移动触发低层切变线形成。冰雹发生前大气有不稳定能量和水汽输送条件。850hPa低空冷空气的侵入加剧了大气层结不稳定,促进不稳定能量的释放。产生冰雹天气,高低空急流配合为强对流发展提供了动力条件。多普勒雷达资料表明,强对流天气有多个对流单体组成,发展强盛时有弓形、钩状和V形缺口等特征,强回波区为50~60dBz,最大达67dBz。径向速度有辐合区和逆风区。逆风区出现于冰雹前1h,是冰雹出现的强信号。液态水含量为20~40km/m^2,最大垂直液态水含量为50km/m^2。出现冰雹的对流单体回波顶高9.11km。垂直风廓线。中风向、风速出现较大垂直切变。 相似文献
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[目的]分析2010年8月晋城一次大暴雨天气过程。[方法]利用常规气象资料、自动站资料、多普勒雷达资料、卫星云图等资料,从环流背景、物理量场、卫星云图、雷达回波特征等方面,对2010年8月18~19日发生在山西晋城的一次强降雨过程进行综合分析。[结果]此次暴雨产生于西低东阻的环流场中,是在中低层切变线、低空急流等有利的天气形势下产生的,低层切变、风向辐合均有利于晋城地区附近不稳定空气的抬升,而对流层低层和地面冷空气的入侵是这次对流天气产生的主要触发机制;西南低空急流为暴雨区输送了充沛的水汽,高温高湿为暴雨的发生积蓄了大量的不稳定能量;这次过程的主要降水系统是地面中尺度切变线扰动激发的对流回波单体,对流回波单体在中低空西南气流的引导下,向晋城移动形成列车效应,在晋城地区产生了大暴雨;多普勒雷达资料揭示了此次中尺度暴雨系统的发生、发展、移动的特征;强降水中心位于TBB低值中心后方的梯度大值区内。[结论]该研究为此类短时暴雨的预报、预警提供借鉴。 相似文献
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