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81.
A 2-year-old male castrated Cavalier King Charles Spaniel was presented with paraplegia, cold caudal extremities and lack of femoral pulses. A 2 cm long thrombus occluding the aortic trifurcation and a 3 cm long abdominal aortic aneurysm with a thrombus were detected by ultrasonographic examination. The clinical and ultrasonographic findings were consistent with aortic thromboembolism. Anti-thrombotic and vasodilative therapy was not helpful and the dog was euthanized 3 days after the onset of paraplegia. A thrombus in the aortic trifurcation, multiple thoracic and abdominal aneurysms and a distal mediastinal esophageal granuloma containing Spirocera lupi worms were found on necropsy. The abdominal aortic aneurysms formed by S. lupi larval migration are believed to be responsible for the formation of the thrombus that occluded the aortic trifurcation. This is the first report of aortic thromboembolism associated with S. lupi infection. 相似文献
82.
Gal A Loeb E Yisaschar-Mekuzas Y Baneth G 《Veterinary journal (London, England : 1997)》2008,175(2):212-217
A molecular study for the detection of Ehrlichia canis was carried out on tissues obtained at necropsy from randomly selected dogs with the intention of investigating naturally-occurring canine ehrlichiosis. The tissues evaluated for the presence of E. canis included lymph nodes, spleen, liver, bone marrow, and blood. Eight of the 18 dogs included were found to be positive for E. canis by polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene. Two dogs were positive for Anaplasma platys of which one dog was co-infected with E. canis and A. platys. Blood (5/8) and lymph nodes (5/8) were the tissues found to yield the highest number of positive E. canis PCR results with 7/8 dogs positive in the blood or lymph node. E. canis and A. platys DNA could be amplified by PCR when tissue samples were obtained 72h after the time of death. 相似文献
83.
The Effect of Urine Concentration and pH on the Growth of Escherichia Coli in Canine Urine In Vitro 下载免费PDF全文
84.
Entry of the bacterium Salmonella typhimurium into host cells requires membrane ruffling and rearrangement of the actin cytoskeleton. Here, it is shown that the bacterial protein SipA plays a critical role in this process. SipA binds directly to actin, decreases its critical concentration, and inhibits depolymerization of actin filaments. These activities result in the spatial localization and more pronounced outward extension of the Salmonella-induced membrane ruffles, thereby facilitating bacterial uptake. 相似文献
85.
Purpose
Assess the refractive states of donkeys and goats.Methods
Forty-two donkeys and 28 goats were enrolled. The mean ± SD ages were 7.68 ± 7.33 years for donkeys and 4.26 ± 2.33 years for goats. Seven donkeys and one goat were <6 months old. Retinoscopy was performed in alert animals, following cycloplegia in goats but not in donkeys. Normality was determined using the Kolmogorov–Smirnov test. The two primary meridians and two eyes were compared using Pearson's correlation and paired Student's t–tests. The association between refractive states and age was examined using one-way ANOVA in donkeys and a paired Student's t-test in goats. One-sample t-tests were conducted to assess if the refractive error distributions were significantly different from “0”.Results
The mean ± SD spherical equivalent (SE) refractive errors of the right and left donkey eyes were −0.80 ± 1.03 D and −0.35 ± 0.95 D, respectively. The majority (86%) of the donkeys had an astigmatic refraction and eight (19%) had anisometropia. The mean SE refractive errors of the right and left goat eyes were −0.15 ± 1.1 D and −0.18 ± 1.2 D, respectively. The majority (54%) of the goat eyes had an astigmatic refraction and five (18%) had anisometropia. The right and left eye SE refractive errors were positively correlated in both species (both p = .9). Age was not correlated with refractive error in both donkeys (p = .09) and goats (p = .6).Conclusions
Both goats and donkeys are emmetropic. 相似文献86.
87.
Harel Gal Zeev Ronen Noam Weisbrod Ofer Dahan Ronit Nativ 《Soil biology & biochemistry》2008,40(7):1751-1757
In the United States, perchlorate has been officially recognized as an environmental contaminant. In Israel, widespread perchlorate contamination has been found in the 40-m deep vadose zone near an ammonium perchlorate manufacturing plant north of Tel Aviv, above the central part of Israel's coastal aquifer, with peak concentrations of 1200 mg kgsediment?1. In this study, we examined the perchlorate-reduction potential by native microbial communities along this deep contaminated vadose zone profile. We analyzed the effect of various concentrations of nitrate on perchlorate reduction and determined whether perchlorate concentrations in the profile are toxic to the native microbial population. All experiments were performed in soil slurries with sediments taken from the contaminated site. Perchlorate was reduced to chloride in three (1, 15 and 35 m) of the four examined sediment samples taken from different depths (1, 15, 20, and 35 m below surface). No activity was observed in the sediment sample from 20 m below land surface, suggesting low viable microbial communities and water content, and high perchlorate concentrations. In the presence of nitrate, the lag time for perchlorate degradation was inversely correlated to nitrate concentration. We found no perchlorate degradation as long as nitrate was present in the system, and perchlorate degradation initiated only after all the nitrate had been reduced. Nitrate-reduction rates were correlated to the initial concentrations of nitrate and no lag period was observed for nitrate reduction. Viable microbial populations were observed at both high concentrations (10,000 mg l?1 and 20,000 mg l?1) and with no addition of perchlorate, at levels of 2.35 × 105, 4.01 × 105, and 3.41 × 103 CFU ml?1, respectively; these results were well correlated to those found by PCR amplification analysis of chlorite dismutase. We suggest that the microbial community has adapted to the conditions of high perchlorate concentrations in the unsaturated zone over 30 years of exposure. When no external carbon source was added to the slurry of soil from land surface, all perchlorate was removed after 134 days of incubation. The average perchlorate-reduction rate using natural organic matter as a carbon source was 0.45 mg day?1, while the average rate using acetate as an external carbon source was 7.2 mg day?1. 相似文献
88.
The WaDI (water delivery for irrigation) model deals with the relations between the collective water supply and the demand within irrigated schemes. It is based on a separate modelling of the water supply and demand, including (i) a simplified representation of the hydraulic structure, characteristics and organizational parameters of the scheme, (ii) an assessment of the water demand of farms based on their total irrigated area, cropping pattern and irrigation practices, (iii) a farm typology, (iv) a confrontation between water demand and supply at each node of the scheme from pumping plants to tertiary canals, and (v) calculation of response factors between supply and demand during the peak demand period. “What-if” scenarios are simulated in order to enhance the stakeholders’ capacity to plan strategic decisions such as water delivery allocation rules or infrastructure investments. WaDI was implemented on two Brazilian schemes. It allowed broadening the stakeholders’ limited representation of collective water supply and demand into a more comprehensive understanding of these relations. The approach however showed some limits, along with the difficulty of assessing the real impact on the stakeholders’ capacity for strategic planning. 相似文献
89.
Erin Nelson Steffanie Scott Judie Cukier Ángel Leyva Galán 《Agriculture and Human Values》2009,26(3):233-243
Over the past two decades, Cuba has become a recognized global leader in sustainable agriculture. This paper explores how
this process of agricultural transition has taken place, and argues that it has largely been led by research institutes, non-state
organizations and the Cuban government, which have all contributed to the institutionalization of agroecology in both policy
and practice. This process has been highly effective in terms of the numbers of people using agroecological techniques. However,
although these techniques have been widely adopted by farmers across the country, this paper suggests that many still perceive
maximizing production to be a higher priority than maintaining a commitment to agroecological ideals. For these farmers, agroecological
farming is viewed primarily as a pragmatic decision rather than an ideological or moral one, and they may thus be susceptible
to shifting back to conventional production if this option became politically and economically feasible
Erin Nelson (M.A., University of Waterloo) is a doctoral candidate in the Rural Studies Program of the School of Environmental Design and Rural Development at the University of Guelph, Ontario, Canada. Her research focuses on local organic food systems. Steffanie Scott (PhD, University of British Colombia) is Assistant Professor in the Department of Geography and Environmental Management in the Faculty of Environment at the University of Waterloo, Ontario, Canada. Her current research focuses on rural development, small farmers, and the restructuring of local food systems. Judie Cukier (PhD, University of Waterloo) is Associate Professor in the Department of Geography and Environmental Management in the Faculty of Environment at the University of Waterloo, Ontario, Canada. Her current research focuses on the impacts of tourism in developing countries. ángel Leyva Galán (PhD, University of Leipzig) is Researcher and Professor at Cuba′s National Institute of Agricultural Sciences. His current work focuses on polyculture and the restoration of biodiversity in areas previously dedicated to monocrop sugar plantation. 相似文献
Steffanie Scott (Corresponding author)Email: |
Erin Nelson (M.A., University of Waterloo) is a doctoral candidate in the Rural Studies Program of the School of Environmental Design and Rural Development at the University of Guelph, Ontario, Canada. Her research focuses on local organic food systems. Steffanie Scott (PhD, University of British Colombia) is Assistant Professor in the Department of Geography and Environmental Management in the Faculty of Environment at the University of Waterloo, Ontario, Canada. Her current research focuses on rural development, small farmers, and the restructuring of local food systems. Judie Cukier (PhD, University of Waterloo) is Associate Professor in the Department of Geography and Environmental Management in the Faculty of Environment at the University of Waterloo, Ontario, Canada. Her current research focuses on the impacts of tourism in developing countries. ángel Leyva Galán (PhD, University of Leipzig) is Researcher and Professor at Cuba′s National Institute of Agricultural Sciences. His current work focuses on polyculture and the restoration of biodiversity in areas previously dedicated to monocrop sugar plantation. 相似文献
90.
Yeong-Soon Gal Sung-Ho Jin Young-Il Park Jong-Wook Park Won Seok Lyoo Kwon Taek Lim Sang Youl Kim 《Fibers and Polymers》2011,12(3):291-295
Poly(1-hexyne) was prepared by the polymerization of 1-hexyne by using transition metal catalyst. The instrumental analysis
data on the polymer structure revealed that the poly(1-hexyne) have the conjugated polyene backbone structure with n-butyl
substituents. Poly(1-hexyne) showed UV-visible absorption band at 276 nm and PL spectrum at 415 nm, indicating relatively
blue-shifted PL maximum value. From the relationship plot of the oxidation current density (log i
p,a) as a function of the scan rate (log v), it was found that the oxidation current of poly(1-hexyne) versus the scan rate is approximately linear relationship in
the range of 30∼150 mV/sec and the exponent of scan rate, x value is found to be 0.424. It is explained by that the kinetics
of the redox process are close to the diffusion-control process. The band gap energy of poly(1-hexyne) was estimated to be
2.98 eV and HOMO and LUMO level values of poly(1-hexyne) were 5.35 and 2.37 eV, respectively. 相似文献