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A 9-year-old spayed female Bengal Red cat was evaluated for high-rise syndrome. The cat had paraplegia of the hind limbs, intact reflexes and pain perception, and hyperesthesia in the caudal thoracic area. Mentation, cranial nerve function, forelimb proprioceptive responses, and spinal reflexes were normal. There were no abnormalities on radiographs or computed tomography scan, but magnetic resonance imaging revealed a hyperintense intraparenchymal spinal cord lesion on T2-weighted and T2 fat saturation images.  相似文献   
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The 3rd Veterinary Immunology Committee (VIC) Toolkit Workshop took place at the 9th International Veterinary Immunology Symposium (IVIS) in Tokyo, Japan on 18th August 2010. The Workshop built on previous Toolkit Workshops and covered various aspects of reagent development, commercialization and provision to the veterinary immunology research community. The emphasis was on open communication about current progress and future plans to avoid duplication of effort and to update priorities for reagent development. There were presentations on the major reagent development and networking projects such as the BBSRC/RERAD Immunological Toolbox (2004-2009), US Veterinary Immune Reagent Network (VIRN 2006-2010) that has just received renewal funding for 2010-2014, and EU Network for Animal Diseases Infectiology Research Facilities project (NADIR 2009-2013). There were also presentations and discussions on the use of reagents for assay development, particularly multiplexing, and how these new technologies will underpin basic research developments. Mechanisms for improved information exchange, especially though websites with VIC playing a central role, were identified.  相似文献   
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Enzyme-linked immunosorbent assays (ELISAs) have been used as a diagnostic tool to quantify levels of gastrointestinal nematodes in dairy cattle by measuring Ostertagia ostertagi antibodies in milk. Higher levels of O. ostertagi antibodies measured by ELISA methods, referred to as optical density ratios (ODRs), are associated with decreased milk production in dairy cattle. On-farm management practices (e.g. pasturing techniques and anthelmintic usage) can influence the exposure of cattle to nematode infections and the magnitude of acquired worm burdens. Additionally, environmental and climatic factors, such as land elevation and precipitation, may also influence the levels of gastrointestinal parasitism. This repeated cross-sectional study investigated the effect of farm management practices and surrounding environmental factors on bulk tank (BT) ODRs in herds from provinces across Canada, and further examined the potential effects of various anthelmintic treatment protocols on BT ODRs. A total of 195 herds contributed an average of 3.5 BT samples between December 2003 and April 2005. The farm management practices were recorded from a questionnaire asking producers about their pasturing methods (confined, pastured, etc.), pasture sharing practices (e.g. mixing heifers with milking cows) and anthelmintic treatments. Environmental data were downloaded online from various governmental databases (e.g. Natural Resources Canada, Statistics Canada, Environment Canada, etc.). Statistical models, accounting for repeated measures (multiple BT ODRs for each farm) and for clustering of farms within a region (province or ecoregion), were used to analyze environmental and farm management data. Overall, the greater the exposure that heifers and milking cows had to pasture, the higher the levels of anti-parasite antibodies detected in BT samples. Treating the entire herd or treating milking cows at calving reduced BT ODR values. Farms in areas with higher number of rainy days, higher normalized difference vegetation index (NDVI) values, and lower land surface temperatures (LSTs), were also likely to have higher BT ODRs. Seasonal variation was such that late summer and early fall, when parasite load was at its highest, yielded larger BT ODRs. Due to the high clustering effect at the herd level, factors at the herd level (e.g. pasturing methods, anthelmintic administration) had a higher potential impact on bulk-tank measurements than the herd's surrounding environmental factors.  相似文献   
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Increasing our knowledge of unplanned anthropogenic synergies, which have affected ecosystems since prehistory, may facilitate ecological restoration. Predictive relationships between spatial pattern and ecosystem processes and functions in riverscapes have the potential to inform applied ecosystem restoration planning and design, where principles are needed for large-scale river reconnections. Although synergistic, additive, and antagonistic interactions affect ecosystems, the role of such interactions in restoration rarely has been evaluated. Using hydrodynamic modeling, we experimentally examine the aggregate effects of reestablishing hydrologic connections in a tidal freshwater tributary on the floodplain of the Columbia River, USA, which is currently undergoing dike breaching to restore juvenile salmon habitat. Sets of dike breaches yielded average wetted floodplain areas conforming to a two-parameter hyperbola (r 2 = 0.93). These findings demonstrate that the yield of inundated floodplain habitat area from dike breaching can conform to the well-established “law of the diminishing increment,” developed in the study of agriculture and economics. Furthermore, the influence of spatial configuration on yield was strong, with midstream breaches yielding 63% and upstream breaches 2% of the wetted area produced by downstream breaches, although conditions of extreme high river flow were not studied. Opening the dike at 26% of the historically present channel outlets provided the maximum return on investment for the study riverscape. Verification of this relationship elsewhere in tidal areas of the Columbia River and on other large river floodplains would contribute to cost-benefit analyses in ecological restoration program planning and have implications for effects on biota.  相似文献   
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The goal of this study is to clarify the surface-chemical and microphysical variables that influence bacterial spore transport through soil, thereby defining the factors that may affect spore transport velocity. Bacillus cereus spores were continuously monitored in a soil column under saturated conditions with experimental variations in soil grain size (0.359 and 0.718 mm), pH (7.2 and 8.5), and water flow rate (1.3 and 3.0 mL/min). Increasing soil grain size, flow rate, and pH resulted in enhanced spore movement. Spore transport increased 82% when soil grain size was doubled. An increase in effluent flow rate from 1.3 to 3.0 mL/min increased spore movement by 71%. An increase in pH increased spore transport by 53%. The increase in hydrodynamic forces resulting from the larger grain size soil and higher flow rate functioned to overcome the hydrophobic nature of the spore’s coat, and the interparticle bonding forces between the spore and soil particles.  相似文献   
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