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Corneal ulceration is a common ophthalmic condition in horses. It is frequently caused by trauma to the corneal surface, followed by secondary infection by commensal or pathogenic organisms including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Staphylococcus spp. Emerging antimicrobial resistance amongst these organisms has raised the need for appropriate antimicrobial therapy selection, to optimise treatment efficacy while minimising further antimicrobial resistance. Medical records of 38 horses presented at the University Veterinary Teaching Hospital Camden for ulcerative keratitis between 2010 and 2020 were reviewed to identify those with positive bacterial cultures and antimicrobial susceptibility profiles (13/38). Common susceptibility patterns were identified and used to guide the empirical treatment of equine bacterial corneal ulcers. Pseudomonas spp. (64.3%), Streptococcus equi subspecies zooepidemicus (14.3%) and Actinobacillus spp. (14.3%) were most commonly identified. Susceptibility to amikacin, gentamicin and ciprofloxacin was observed in 100%, 66.7% and 85.7% Pseudomonas spp. isolates respectively. Resistance to polymyxin B and neomycin occurred in 85.7% and 71.4% of Pseudomonas spp., respectively. All Streptococcus equi subspecies zooepidemicus organisms in this study were susceptible to ceftiofur, cephalexin, penicillin and ampicillin, while they were all resistant to gentamicin, neomycin, enrofloxacin and marbofloxacin. Predominating in this study, Pseudomonas spp. maintained overall aminoglycoside susceptibility despite some emerging resistance, and good fluoroquinolone susceptibility. High resistance to Polymyxin B could have arisen from its common use as first-line therapy for bacterial corneal ulcers. Although further research is required, these new findings about predominant bacteria in equine corneal ulceration in the Camden region and their antimicrobial susceptibility patterns can be used to guide the empirical treatment of bacterial corneal ulcers in horses. 相似文献
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With the study of minbus's accelerated exterior noise control,the principle of sound intensity measurement was applied,the sound intensity of a minbus's surface noise was tested,and the surface noise distribution was presented.Several identification of noise source methods including sound power,sound intensity contour map,frequency spectrum were used together for surface noise analysis and study.Engine radiation noise and exhaust noise was identified as the major noise sources.On the contrary,car body vibration noise,tyre noise,transmission agent noise,air admission noise just occupied a little proportion of surface sound radiation energy.The research provides the reliable basis to determine main projects of minibus's accelerated exterior noise control. 相似文献
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高效脱色菌的特性及其在染化废水厌氧处理中的生物强化作用 总被引:14,自引:0,他引:14
从活性污泥等微生物源中分离、筛选获得10株高效脱色菌,经鉴定其属于Pseudomonas,Bacillus,Xanthomonas,Erwinia,Alealigenes,Plesiomonas。对艳红染料生产废水脱色试验表明最适温度30℃,pH6.6~8.0,湿细胞浓度20~30!g*L-1;静置培养(兼氧)脱色率高于振荡培养;外加NADH、NADPH、易降解有机物和有机废水可强化脱色菌的脱色性能。为实现脱色菌的资源化应用,试验将PseudomonasD18,ErwiniaD17,AlcaligenesD19andPlesiomonasD124株脱色菌制成混合培养物和固定化细胞,分别投加于处理染化废水的厌氧反应器,结果发现在相同COD负荷、水力负荷条件下,投加固定化细胞的反应器,其脱色率可提高5!%~10!%,出水苯胺浓度提高40!%~65!%。电镜观察发现脱色菌在胶团内外持留、增殖。厌氧反应器性能的改善主要通过功能性微生物生物量和相关基因库量的增加而实现。 相似文献
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陈正洪 《华中农业大学学报》1993,12(4):369-375
本文根据主导因子及综合分区原理,对与我省森林火灾有关的主要气候要素进行单项及综合区划,共得到3级共8个林火气候区,其中,重、中等火灾区各占1/7,轻火灾区占5/7。 相似文献
100.
《Journal Of Aquatic Food Product Technology》2013,22(3):43-58
Current shrimp quality evaluation is a subjective sum of visual, smell and texture characteristics, and the manual determination of count and uniformity ratio of a sample batch. The automation of this process is desirable for a more rapidly and objectively repeatable evaluation. As a first step towards this goal, the count and uniformity ratio of whole, headless, peeled-tail-on, and peeled-tail-off tiger and white shrimp were evaluated by a machine vision procedure. The experimental weight and view area were correlated by three different equations (linear, power, and forced-power curves) to find the best correlation. The pixel intesities as it relates to lightness-darkness values were also correlated to see if different forms and species could be distinguished by this method. Data, equations and statistics for the correlations are presented. 相似文献