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21.
The efficacy and safety of pharmacological interventions to treat canine Pseudomonas otitis externa and media were evaluated based on the systematic review of clinical trials published between 1967 and 2006. Clinical trials were included if Pseudomonas species were cultured from the ears of dogs with otitis externa or otitis media prior to treatment, and if the outcome of these interventions was reported at the end of the study. Studies were compared with regard to design characteristics (randomization generation and concealment, masking, intention-to-treat analyses), benefit (microbiological and/or clinical resolution of the Pseudomonas otitis), and adverse effects. Ten trials reporting data on 162 patients and 13 different pharmacological interventions were identified. Based on the accepted criteria for quality of evidence, there is insufficient evidence for or against recommending the use of any of these treatments for Pseudomonas otitis in dogs. This is largely because there is only one trial supporting the use of each treatment option and none were randomized controlled trials. Future studies need to be prospective, randomized, blinded and controlled; designed to evaluate pharmacological interventions for otitis regardless of the infective organism; have appropriate statistical advice on recruitment numbers, the power of the study and appropriate statistical analysis; include details of underlying conditions and concomitant treatments; and be designed such that inclusion criteria include microbial culture and antimicrobial sensitivity, and outcome assessments include clinical examination, cytology and microbial culture.  相似文献   
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Summary Citrus orchards (cv. Valencia and cv. Washington Navel Orange) on sandy soils in semi-arid South Australia (evaporation 1,900 mm, rainfall 240 mm) are irrigated with water from the River Murray having a chloride content of less than one to over 10 meq/1 (electrical conductivity 0.35–1.4 dS/m). Field observations and the literature suggest that at irrigation water salinities above 4 meq/1 Cl-, yield losses might be expected due to toxic effects of chloride rather than osmotic effects.To assess these effects irrigations at four salinity levels (range 2 to 5 meq/1 Cl) were applied to mature oranges trees (cv. Washington Navel) grown on Rough Lemon rootstock. Irrigations were carefully scheduled, with a total annual application of about 1,100 mm. The treatments resulted in soil salinities of 0.9 to 1.5 mS/cm (as measured with 4-electrode probes, at a depth of 0–50 cm), leaf chloride content on individual trees of 0.2% to 1.2%, and individual tree yields of 300 to 340 kg of fruit. On this orchard, a yield decrement of about 20% per 1 meq/1 chloride in the irrigation water was calculated, above a threshold level of about 4.3 meq/1 (Fig. 5). Reasons are given to support the view that the yield decrements found were probably due to chloride toxicity rather than osmotic stress.  相似文献   
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Landscape Ecology - Anthropogenic disturbance alters animal movements. Large mammals require vast areas to meet their needs, and they encounter anthropogenic disturbances frequently during daily...  相似文献   
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Two aborted Chester White pig fetuses were presented to a veterinary diagnostic laboratory in Illinois. Postmortem examination identified no gross abnormalities. Histologic evaluation revealed multifocal necrosis of chorionic epithelial cells, coalescing areas of mineralization in the placenta, and focal accumulations of viable and degenerate neutrophils in the lung. Intra- and extracellular acid-fast bacilli were identified in the lesions in both the placenta and lungs. Bacterial culture of stomach contents yielded heavy growth of Mycobacterium fortuitum, a rapidly growing nontuberculous mycobacterium (NTM), which was further confirmed through whole-genome sequencing. NTM are opportunistic pathogens commonly found in the soil and in contaminated water supplies. In animals, M. fortuitum is typically introduced through cutaneous wounds leading to infections limited to the skin, with systemic infection being uncommon. To our knowledge, abortion caused by M. fortuitum has not been reported previously.  相似文献   
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The objective of this cross-sectional study was to evaluate the presence of infectious disease in newly arrived cattle on dairy farms in Ontario. Cattle that were more than 2 years old and arrived at dairy farms within the previous year were tested. A total 321 cattle from 56 dairy farms were sampled and had blood submitted to a diagnostic laboratory. Of all sampled cattle, 0.0%, 39.6%, 2.2%, and 1.3% tested positive for Anaplasma, bovine leukemia virus, Mycobacterium avium subsp. paratuberculosis, and Salmonella Dublin, respectively. Based on these results, it is imperative that dairy producers are vigilant to ensure they do not purchase animals with these important and untreatable infectious diseases.  相似文献   
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Three practical-type diets utilizing fishmeal and casein as the protein sources and containing fish oil (FO), safflower oil (SO) or linseed oil (LO) were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.2 g for a period of 12 weeks. No differences in final weight, mortality or development of pathological lesions were evident either between duplicate tanks or between dietary treatments over this period. Fish fed diets containing SO and LO contained significantly greater amounts of liver triacylglycerol compared to fish fed FO. The major C18 polyunsaturated fatty acids (PUFA) in SO and LO diets, 18:2(n-6) and 18:3(n-3) respectively, were readily incorporated into both total lipid and individual phospholipids of turbot tissues. There was no accumulation of the Δ6-desaturation products of these fatty acids, namely 18:3(n-6) and 18:4(n-3), in any of the tissues examined. The products of elongation of 18:2(n-6) and and 18:3(n-3), 20:2(n-6) and 20:3(n-3) respectively, accumulated in both total lipid and phospholipids with the highest levels of 20:2(n-6) in liver PC and 20:3(n-3) in liver PE. Eicosapentaenoic acid [EPA, 20:5(n-3)] levels exceeded those of arachidonic acid [AA, 20:4(n-6)] in phosphatidylinositol (PI) from liver and gill of fish fed LO. EPA levels in liver PI from fish fed LO were 3-fold and 2-fold greater than SO-fed and FO-fed fish, respectively. Fish fed diets containing SO and LO had significantly reduced levels of AA in liver and muscle total lipid and lower AA in individual phospholipid classes of liver and gill compared to FO-fed fish. The concentration of thromboxane B2 was significantly reduced in plasma and isolated gill cells stimulated with calcium ionophore A23187 of fish fed SO and LO compared to those fed FO. Prostaglandin E produced by isolated gill cells stimulated with A23187 was significantly reduced in fish fed both SO and LO compared to fish fed FO.  相似文献   
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In recent years social, economic and environmental considerations have led to a reevaluation of the factors that contribute to sustainable urban environments. Increasingly, urban green space is seen as an integral part of cities providing a range of services to both the people and the wildlife living in urban areas. With this recognition and resulting from the simultaneous provision of different services, there is a real need to identify a research framework in which to develop multidisciplinary and interdisciplinary research on urban green space. In order to address these needs, an iterative process based on the delphi technique was developed, which comprised email-mediated discussions and a two-day symposium involving experts from various disciplines. The two outputs of this iterative process were (i) an integrated framework for multidisciplinary and interdisciplinary research and (ii) a catalogue of key research questions in urban green space research. The integrated framework presented here includes relevant research areas (i.e. ecosystem services, drivers of change, pressures on urban green space, human processes and goals of provision of urban green space) and emergent research themes in urban green space studies (i.e. physicality, experience, valuation, management and governance). Collectively these two outputs have the potential to establish an international research agenda for urban green space, which can contribute to the better understanding of people's relationship with cities.  相似文献   
30.
The use of variable rate technology has become increasingly popular for applying plant nutrient elements. The most widely used method for determining variable fertilizer rates is presently based on soil testing and yield mapping. Three field studies (Bumeyville 1995, Burneyville 1996, and Ardmore 1996) were initiated in established Midland bermudagrass [Cynodon dacrylon (L) Pers.] pastures to determine the relationship between spectral radiance at specific wavelengths with forage nitrogen (N) removal and biomass, and to determine field variability of soil test parameters. Variable N (applied to 1.5 × 2.4 m subplots within 2.4 × 45.7 m main plots), fixed N and check treatments were evaluated at each location. Spectral radiance readings were taken in the red (671±6 nm), green (570±6 nm), and near infrared (NIR) (780±6 nm) wavelengths. The normalized difference vegetation index (NDVI) was calculated as NIR‐red/NIR+red. Variable N rates were applied based on NDVI. The highest fixed variable N rate was set at 224, 336, and 672 kg N ha‐1 for Burneyville, 1995, 1996, and Ardmore, 1996, respectively. At Bumeyville, soil samples were collected in all variable rate plots (1.5 × 2.4 m) and analyzed for various soil test characteristics. NDVI, red, green, and NIR spectral radiance readings were correlated with bermudagrass forage N removal and yield. Correlation of forage yield and N removal with red, NIR, and NDVI were best with maximum forage production, however, when forage production levels were low correlation decreased dramatically for the red wavelength compared with NIR and NDVI. Forage yield and forage N removal in variable rate treatments increased when compared to the check while being equal to the half‐fixed and fixed rates where higher N rates were applied. Also, variability about the mean in variable rate plots was significantly lower than half‐fixed and fixed rates which supports adjusting N rates based on indirect NDVI measurements. Variable N rate plots reduced fertilizer inputs by 60% and produced the same yield as fixed rate plots, while fixed and half‐fixed rates did not increase N content in the forage over that of the variable rate treatment. Soil sample data collected from small consecutive plots (<4 m2) was extremely variable indicating that intense sampling would be needed if variable fertilizer application were to be based on soil test results.  相似文献   
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