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Guy D. Lester BVMS PhD Christophe W. Lombard DVM Norman Ackerman DVM 《Veterinary radiology & ultrasound》1992,33(4):202-205
A 12-year-old Thoroughbred stallion was referred with a history of acute pain and tachycardia immediately after breeding a mare. On presentation, the horse showed no evidence of pain and routine examination of the abdomen failed to yield any abnormalities, however, a persistent tachycardia remained. A base-apex ECG examination revealed sustained ventricular tachycardia which resolved spontaneously within 12 hours of hospitalization. During this period, the stallion developed a grade 4/6 heart murmur. An aortic root aneurysm in the right sinus of Valsalva was diagnosed using two-dimensional echocardiography. Pulsed-wave Doppler evaluation revealed turbulent flow within the aneurysm. Repeat echocardiographic examination 10 months after the onset of signs revealed no change and the horse continues to perform as a breeding stallion. 相似文献
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Gardner IA Nielsen SS Whittington RJ Collins MT Bakker D Harris B Sreevatsan S Lombard JE Sweeney R Smith DR Gavalchin J Eda S 《Preventive veterinary medicine》2011,101(1-2):18-34
The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock studies such as herd tests, potential use of experimental challenge studies, a more diverse group of testing purposes and sampling designs, and the widespread lack of an ante-mortem reference standard with high sensitivity and specificity. The objective of the present study was to develop a modified version of STARD relevant to paratuberculosis (Johne's disease) in ruminants. Examples and elaborations for each of the 25 items were developed by a panel of experts using a consensus-based approach to explain the items and underlying concepts. The new guidelines, termed STRADAS-paraTB (Standards for Reporting of Animal Diagnostic Accuracy Studies for paratuberculosis), should facilitate improved quality of reporting of the design, conduct and results of paratuberculosis test accuracy studies which were identified as "poor" in a review published in 2008 in Veterinary Microbiology. 相似文献
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Habitat loss through development is one of the major causes of biodiversity loss. The increasingly common legal requirement to first avoid, then reduce and, if necessary, offset impacts of plans and projects on biodiversity has however not always been appropriately enforced. The blame lies mainly in bad governance such as patchy monitoring or poorly defined liabilities. Biodiversity offsets also suffer from the lack of formal methods for designing and sizing offset requirements. We address this gap by reviewing different tools, methods and guidelines that have been developed in different regulatory contexts. We then formulate a typology of approaches that variously combine these methods and guidelines. We discuss how these relate to the objectives of offset policies and the components of biodiversity and ecosystems to which they apply. Together, these perspectives should contribute to improving existing methods (e.g. by incorporating time-related issues) and our typology should support the development of offset policies. 相似文献
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Cowen JP Giovannoni SJ Kenig F Johnson HP Butterfield D Rappé MS Hutnak M Lam P 《Science (New York, N.Y.)》2003,299(5603):120-123
Little is known about the potential for life in the vast, low-temperature (<100 degrees C) reservoir of fluids within mid-ocean ridge flank and ocean basin crust. Recently, an overpressured 300-meter-deep borehole was fitted with an experimental seal (CORK) delivering crustal fluids to the sea floor for discrete and large-volume sampling and characterization. Results demonstrate that the 65 degrees C fluids from 3.5-million-year-old ocean crust support microbial growth. Ribosomal RNA gene sequence data indicate the presence of diverse Bacteria and Archaea, including gene clones of varying degrees of relatedness to known nitrate reducers (with ammonia production), thermophilic sulfate reducers, and thermophilic fermentative heterotrophs, all consistent with fluid chemistry. 相似文献
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A.T. Lombard 《African Zoology》2013,48(3):63-70
During the Zoological Society of Southern Africa's 1994 Symposium in Pietermaritzburg, a theme session was convened to evaluate the protection status of selected groups of South African vertebrates (viz. freshwater fish, frogs, tortoises and terrapins, snakes, birds, and various mammal orders). The research papers presented during that session are reported in this number of the South African Journal of Zoology. The rationale behind the research, and the data and methods used, are described in this introductory paper. South Africa's national and international contractual obligations to conserve its biodiversity, and the urgent need for a national conservation strategy and national conservation information networks and databases, are also discussed. 相似文献