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排序方式: 共有254条查询结果,搜索用时 15 毫秒
61.
62.
Schoenbaum MA Hall SM Glock RD Grant K Jenny AL Schiefer TJ Sciglibaglio P Whitlock RH 《Journal of the American Veterinary Medical Association》2000,217(3):365-8, 340
A USDA Early Response Team investigated deaths of several horses and a mule in northern Arizona at the request of local animal health officials. Thirteen animals (12 horses and 1 mule) housed at 5 facilities in a 7.4 square mile area died between August 1998 and January 1999. Clinical signs consisted of muscular weakness that rapidly progressed to lateral recumbency. Ten animals had paresis of the tongue, throat, or lips. Affected animals appeared alert and were interested in eating and drinking, even while recumbent. All 13 animals were euthanatized. Clostridium botulinum type C was isolated from feces or intestinal contents from 3 affected horses. Preformed toxin was detected in samples of soil and bird droppings collected from a nearby horse burial site. It was hypothesized that the outbreak was a result of birds, presumably ravens, feeding at the burial site and at horse facilities in the area that transferred toxin to the affected animals. 相似文献
63.
J Peters J M Miller A L Jenny T L Peterson K P Carmichael 《Journal of veterinary diagnostic investigation》2000,12(6):579-582
An immunohistochemical (IHC) method was used to test brain tissues from 17 elk in a captive herd in which chronic wasting disease (CWD) had previously occurred. The IHC technique detects the protease-resistant prion protein (PrP-res), which is considered a disease-specific marker for transmissible spongiform encephalopathies (TSE), regardless of the species affected. Of the 17 elk tested, 10 were positive by IHC. Only 2 of these 10 animals had shown clinical signs and histologic lesions of CWD, and an additional animal had histologic lesions only. The most consistently IHC-positive tissue was medulla oblongata, especially the obex. These results show that the PrP-res IHC test on brain tissue, specifically medulla oblongata at the obex, should be considered an essential component of any surveillance study intended to determine the incidence of CWD in captive or free-ranging cervids. 相似文献
64.
Studies were conducted to evaluate the effect of a kaolin-based particle film against the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae). The effect of the particle film on development, survival and host plant selection was tested on calabrese seedlings, Brassica oleracea italica Plenck cv. Fiesta F(1), under controlled environmental conditions in the laboratory. Survival to adulthood was significantly reduced and development time increased on kaolin-treated compared with water-treated host plants. The hatch rate of neonate P. xylostella larvae from eggs laid on an artificial substrate was unaffected by the particle film applied after oviposition. Experiments showed that, when given the choice, significantly fewer larvae first made contact with the kaolin-treated compared with the water-treated plant material and that after 24 h there were still significantly fewer larvae present on kaolin-treated leaves. Adult females, however, deposited more eggs on host plants coated with the kaolin particle film. As part of this series of experiments the water control treatment was compared with plant material which had been sprayed with kaolin on the upper surface only and on both leaf surfaces. In general, any observed treatment effect was enhanced with an increase in the particle film coverage. The results warrant the extension of investigations of kaolin-based particle films to field-based P. xylostella management strategies. 相似文献
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Emma L. Gillingham Jessica L. Hall Richard J. Birtles Kevin J. Bown Jolyon M. Medlock Robert Smith Kayleigh M. Hansford Jenny C. Warner Matthew Dryden Maaike E. Pietzsch 《Zoonoses and public health》2020,67(5):591-599
Lyme borreliosis (LB) is a tick‐borne disease caused by Borrelia burgdorferi sensu lato complex. In Europe, it is predominately transmitted by the sheep tick, Ixodes ricinus. Compared with other European countries, the United Kingdom (UK) is considered to have a low incidence of LB, although this varies regionally. To determine whether an association exists between tick bite consultations and LB incidence in the UK, retrospective questionnaires were sent to general practitioners (GPs) in high (Wiltshire), medium (Cumbria) and low (Wales) incidence areas. During 2011, the greatest incidence of consultations for tick bites was reported by GPs in Cumbria (204 consultations per 100,000 inhabitants), followed by Wiltshire (160 per 100,000 population) and Wales (54 per 100,000 population). In Wiltshire and Cumbria, GPs predominantly provided advice on tick removal, whilst Welsh GPs mostly advised patients on tick bite prevention. Focusing on Cumbria during 2011–2013, 72.5% of GPs removed ticks from patients (incidence of 101 consultations per 100,000 population), and more GPs diagnosed LB based on clinical features than laboratory‐confirmed diagnoses. To date, this is the first study to investigate the incidence of tick bite consultations and LB in England and Wales. 相似文献
67.
Mandala S Hajdu R Bergstrom J Quackenbush E Xie J Milligan J Thornton R Shei GJ Card D Keohane C Rosenbach M Hale J Lynch CL Rupprecht K Parsons W Rosen H 《Science (New York, N.Y.)》2002,296(5566):346-349
Blood lymphocyte numbers, essential for the development of efficient immune responses, are maintained by recirculation through secondary lymphoid organs. We show that lymphocyte trafficking is altered by the lysophospholipid sphingosine-1-phosphate (S1P) and by a phosphoryl metabolite of the immunosuppressive agent FTY720. Both species were high-affinity agonists of at least four of the five S1P receptors. These agonists produce lymphopenia in blood and thoracic duct lymph by sequestration of lymphocytes in lymph nodes, but not spleen. S1P receptor agonists induced emptying of lymphoid sinuses by retention of lymphocytes on the abluminal side of sinus-lining endothelium and inhibition of egress into lymph. Inhibition of lymphocyte recirculation by activation of S1P receptors may result in therapeutically useful immunosuppression. 相似文献
68.
Susanne Schraml William Arthur Barrios Santos Christoph Mülling Claus Bässler Jenny Hagen 《Anatomia, histologia, embryologia》2021,50(3):625-636
This study presents a comparative morphological and morphometrical examination of the interosseous muscle (IOM), digital flexor tendons and associated structures of all four species of South American Camelids (SACs): Lama (Lama glama), alpaca (Vicugna pacos), guanaco (Lama guanicoe) and vicuna (Vicugna vicugna). Our findings show that the lamoid interosseous muscle and digital flexor tendons are very similar between species and differences, which have been reported previously, are possibly due to diverging examiner interpretation. Lumbricalis muscles were mostly found as single muscles in this study. The definition of the terminal and dorsal branches of the interosseous muscle is critically revised. The analysis of morphometric data indicates that the size of the individual has a substantial influence on the cross-sectional area (CSA) of the examined structures. Metacarpal/metatarsal bone width is a main predictor of CSA, while the factor species only shows significance in specific sample points. For lama and alpaca, no differences in CSA in relation to species as factor were found. The IOM shows the largest CSAs of the three examined structures in all species, which implies an important load-bearing function. Considerable individual variation remains unexplained by the mentioned factors. This lowers the prospect of CSA reaching diagnostic importance in SAC fetlock pathology. 相似文献
69.
70.
Komathi Kolandai-Matchett Maria Armoudian Simon Thrush Jenny Hillman Luitgard Schwendenmann Julia Jakobsson Tim Haggitt Caitlin O'Hara Blain Gavin Lear 《水产资源保护:海洋与淡水生态系统》2021,31(11):3034-3055
- The ocean's remoteness, ecological complexities, lengthy ecosystem processes, and vulnerability to multiple and cumulative anthropogenic threats make marine conservation communication particularly difficult. Both scientists and journalists face unique challenges in explaining the science of these often out-of-sight ecosystems. Given the inadequacies of marine news, improvement appeared necessary. However, the experiences and views of journalists and scientists have hardly been examined within marine news contexts. Thus, this study sought the perspectives of these two professional groups to provide a discussion on ways to improve news coverage of complex ocean issues through enhanced journalist–scientist working relations.
- Both journalists and scientists rated the quantity, breadth and quality of marine news as average and were receptive to alternative ways for reporting ecosystem complexities. Although some frustrations remain, both valued impactful news stories resulting from their working relations and preferred direct contact with each other over indirect methods such as press releases and science news platforms. Both groups generally agreed on what to include in marine news, but scientists favoured a collaborative approach to news content decision-making more strongly than journalists.
- Journalists' and scientists' commonly shared views and goals concerning marine news identified in this study could serve as a common ground for uniting the two professions. Institutional policies that permit one-on-one journalist–scientist interactions could lead to mutual understandings about the contexts of their relationship challenges. More trustful and mutually beneficial relationships, in turn, could be a basis for a more collaborative news generation process. Compiling and making marine visuals readily accessible to journalists; training programmes that enhance journalists' and scientists' understanding of the influence of media message framing on conservation actions; media appreciation of marine ecosystem complexities' newsworthiness; and the notion of media's social responsibility in reporting marine conservation issues could contribute to more impactful coverage.