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91.
CANINE HIP DYSPLASIA EVALUATION 总被引:1,自引:0,他引:1
Victor T. Rendano Jr VMD MS Gerald Ryan RT AHT 《Veterinary radiology & ultrasound》1985,26(6):170-186
The ventrodorsal radiograph of the pelvis and femurs with the hind limbs extended, femurs parallel to each other, patellae superimposed over the distal femurs, and the pelvis symmetrical has become the standard method by which to evaluate animals for hip dysplasia. The following illustrated guide details the methods of positioning recommended by the American Veterinary Medical Association1 and used by the Orthopedic Foundation for Animals (OFA). Additionally, some commonly encountered positioning errors and methods of labeling radiographs are shown. The authors stress positioning requirements and aids they feel are necessary to produce an adequately positioned radiograph. 相似文献
92.
P I Menzies S Z Ramanoon 《Veterinary Clinics of North America: Food Animal Practice》2001,17(2):333-58, vii
This article presents an overview of the recent research into ovine and caprine mastitis. The common clinical presentations of mastitis in these species are reviewed, as are the important etiologic agents and their significance. The interpretation of somatic cell counts and surrogate tests, factors that affect somatic cell count levels, and association of somatic cell count levels with productivity are reviewed. Investigations into the treatment and prevention of mastitis and milking equipment function are discussed, and comments are made on the public health implications of extra label drug use and the consumption of unpasteurized milk. 相似文献
93.
Chamberlain SR Menzies L Hampshire A Suckling J Fineberg NA del Campo N Aitken M Craig K Owen AM Bullmore ET Robbins TW Sahakian BJ 《Science (New York, N.Y.)》2008,321(5887):421-422
Obsessive-compulsive disorder (OCD) is characterized by repetitive thoughts and behaviors associated with underlying dysregulation of frontostriatal circuitry. Central to neurobiological models of OCD is the orbitofrontal cortex, a neural region that facilitates behavioral flexibility after negative feedback (reversal learning). We identified abnormally reduced activation of several cortical regions, including the lateral orbitofrontal cortex, during reversal learning in OCD patients and their clinically unaffected close relatives, supporting the existence of an underlying previously undiscovered endophenotype for this disorder. 相似文献
94.
Measurements of the total burden and of the concentration versus altitude profiles of ozone have been made with a ground-based heterodyne radiometer at Pasadena, California. The measurements were made in the 9.5-micrometer wavelength region, where a strong ozone infrared absorption band exists. The radiometer measured solar absorption at selected wavelengths, with a spectral resolution of 0.001 reciprocal centimeter, equivalent to the half-width of an ozone absorption line at the 10-millibar altitude level. A carbon dioxide laser served as the local oscillator. This technique can be used to gather important data on both tropospheric and stratospheric ozone, which are not readily accessible with other remote-sensing techniques. 相似文献
95.
96.
Whilst the topic of soil salinity has received a substantive research effort over the years, the accurate measurement and interpretation of salinity tolerance data remain problematic. The tolerance of four perennial grass species (non-halophytes) to sodium chloride (NaCl) dominated salinity was determined in a free-flowing sand culture system. Although the salinity tolerance of non-halophytes is often represented by the threshold salinity model (bent-stick model), none of the species in the current study displayed any observable salinity threshold. Further, the observed yield decrease was not linear as suggested by the model. On re-examination of earlier datasets, we conclude that the threshold salinity model does not adequately describe the physiological processes limiting growth of non-halophytes in saline soils. Therefore, the use of the threshold salinity model is not recommended for non-halophytes, but rather, a model which more accurately reflects the physiological response observed in these saline soils, such as an exponential regression curve. 相似文献
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98.
Robinson PA Corner LA Courcier EA McNair J Artois M Menzies FD Abernethy DA 《Comparative immunology, microbiology and infectious diseases》2012,35(4):277-287
Tuberculosis (TB) is a significant animal health problem in many parts of the world, and reservoirs of infection in wild animals complicate disease control efforts in farmed livestock, particularly cattle. Badgers (Meles meles) are a significant wildlife reservoir of Mycobacterium bovis infection for cattle in the United Kingdom (UK) and Republic of Ireland (ROI). Vaccination of badgers using an M. bovis strain bacille Calmette-Guérin (BCG) vaccine could potentially be an option in the national TB eradication strategy. Wildlife vaccination has been used successfully for other diseases in wildlife species, and may have a role to play in reducing M. bovis transmission at the wildlife-livestock interface. Research to date has provided evidence that BCG is protective in badgers, and a parenteral badger BCG vaccine has been licensed in the UK. Further research is required to develop effective strategies for vaccine deployment and to determine the effect of badger vaccination on cattle TB incidence. 相似文献
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100.
Lisa Scott Paula Menzies Richard J. Reid-Smith Brent P. Avery Scott A. McEwen Catherine S. Moon Olaf Berke 《Canadian journal of veterinary research》2012,76(2):109-119
The purpose of this study was to examine the prevalence and patterns of antimicrobial resistance (AMR) in enteric bacteria obtained from Ontario sheep flocks, and associations between antimicrobial use (AMU) and AMR. Forty-nine sheep producers participated for a 1-year interval between 2006 and 2008. Two-hundred and eighty-three pooled fecal samples were collected from the flocks during initial and final visits. Up to 3 isolates of Salmonella spp. and generic E. coli per pooled fecal sample were tested for susceptibility to 15 antimicrobials. Resistance was infrequent among Salmonella (0%, n = 7 isolates) and low among E. coli (13.1%; n = 849) isolates. A small number of isolates were resistant to antimicrobials classified as being of very high importance to human health. Tetracycline resistance was most frequently observed (12.0%). Logistic regression was used to model potential AMU (qualitative and quantitative) risk factors for tetracycline resistance in generic E. coli from final visits. Qualitative analysis indicated that the use of injectable sulfonamides [including trimethoprim-sulfonamide combinations (TMS)] and tetracycline in the feed and water were significantly associated with tetracycline resistance (OR = 2.6, P = 0.01; and OR = 4.8, P ≤ 0.01, respectively). Quantitative analysis also indicated that TMS exposure rate was significantly associated with tetracycline resistance, which varied depending on the exposure rate. The exposure rate of tetracycline in the feed and water was only significant after the removal of one influential flock, warranting further research examining flocks with higher tetracycline exposure rates. Although the prevalence of AMR in participating flocks was relatively low, risk factors for resistance were identified. 相似文献