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OBJECTIVE: To evaluate the usefulness of serum biochemical variables and scintigraphic study results for differentiating between dogs and cats with complete extrahepatic biliary obstruction (EHO) and those with partial EHO or patent bile ducts. STUDY DESIGN: Retrospective case series. ANIMALS: 17 dogs and 1 cat. PROCEDURE: Animals that underwent hepatobiliary scintigraphy and had either surgical or postmortem confirmation of the degree of bile duct patency were included. Scintigraphic images were evaluated and biliary tracts were classified as patent, partially obstructed but patent, or obstructed. Surgery or postmortem examination was considered the gold standard for diagnosis, and compared with those findings, sensitivity and specificity of scintigraphy were calculated. RESULTS: With absence of radioactivity in the intestinal tract as the diagnostic criterion for EHO, the sensitivity and specificity of scintigraphic diagnosis were both 83% when final images were acquired at 19 to 24 hours, compared with 100% and 33%, respectively, when 180 minutes was used as the cutoff time. Animals with partial biliary obstruction had less intestinal radioactivity that arrived later than that observed in animals with patent biliary tracts. CONCLUSIONS AND CLINICAL RELEVANCE: Animals in which intestinal radioactivity has not been observed after the standard 3 to 4 hours should undergo additional scintigraphic imaging. Findings in animals with partial biliary obstruction include delayed arrival of radioactivity and less radioactivity in the intestine. Distinguishing between complete and partial biliary tract obstruction is important because animals with partial obstruction may respond favorably to medical management and should not be given an erroneous diagnosis of complete obstruction.  相似文献   
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Vascular encephalopathy is a commonly encountered clinical complication of infectious endocarditis in humans, but it has been infrequently reported in dogs. A series of four dogs with bacterial endocarditis that subsequently developed acute onset of neurological deficits is described. Clinical signs, diagnostic test results, and outcomes for each case are presented and compared with the human clinical syndrome.  相似文献   
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The efficacy of fluorescent pseudomonads as suppressors of soil-borne diseases is linked to their ability to colonise plant roots. Monitoring the dynamics of biocontrol agents in the rhizosphere should improve the irreliability. We designed a pair of Sequenced Characterised Amplified Region (SCAR) primers specific to Pseudomonas fluorescens Pf29A, based on a specific 700 bp RAPD product selected in a previous work. Primer specificity was tested with DNA samples extracted from rhizospheric soil and rhizoplane of wheat plants grown in two different non-sterile soils. We assessed the total population of Pf29A by PCR and the culturable population by counting a tetracycline-resistant Pf29A transformant producing Green Fluorescent Protein (GFP), on selective medium 5 days after inoculation of non-sterile soil. SCAR primers were specific for Pf29A in both soils. We evaluated the limit of detection to 14.2 fg of target DNA, equivalent to 242 Pf29A cells per cm of wheat root. Culturable populations of Pf29A transformant accounted for 13% and 4% of the total populations 5 days after treatment with 103 and 107 CFU of transformed Pf29A per gram of soil. The SCAR derived sequence is a good candidate to develop a strain specific and sensitive PCR-quantification of Pf29A available for population dynamic studies in fields. We confirm that only a small proportion of the total Pf29A rhizosphere population is culturable.  相似文献   
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OBJECTIVE: To document clinicopathologic, histologic, and toxicologic findings in cats inadvertently exposed to pet food contaminated with melamine and cyanuric acid. DESIGN: Case series. ANIMALS: 70 cats from a single cattery inadvertently fed contaminated food that was the subject of a March 2007 recall. PROCEDURES: Clinical signs, clinicopathologic and histopathologic findings, and results of toxicologic analyses were recorded. RESULTS: Clinical signs were identified in 43 cats and included inappetence, vomiting, polyuria, polydipsia, and lethargy. Azotemia was documented in 38 of the 68 cats for which serum biochemical analyses were performed 7 to 11 days after consumption of the contaminated food. One cat died, and 13 were euthanized. Histologic examination of kidney specimens from 13 cats revealed intratubular crystalluria, tubular necrosis with regeneration, and subcapsular perivascular inflammation characterized by perivascular fibroplasia or fibrosis and inflammation with intravascular fibrin thrombi. Toxicologic analyses revealed melamine and cyanuric acid in samples of cat food, vomitus, urine, and kidneys. CONCLUSIONS AND CLINICAL RELEVANCE: In cats unintentionally fed pet food contaminated with melamine and cyanuric acid, the most consistent clinical and pathologic abnormalities were associated with the urinary tract, specifically tubular necrosis and crystalluria.  相似文献   
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An indirect fluorescent antibody (IFA) test was developed and standardized to detect and quantitate antibody for swine infertility and respiratory syndrome (SIRS) virus in swine sera. Test results were evaluated using sera of pigs infected both experimentally and naturally with SIRS virus. The IFA test used swine alveolar macrophage (SAM) monolayers prepared in 96-well microplates and infected with SIRS virus. The monolayers were incubated with test sera, washed, and stained with fluorescein isothiocyanate-labeled rabbit anti-swine IgG. After another wash step, the monolayers were examined under a fluorescent microscope. A noninfected SAM control well was included for each sample. The antibody titers for each serum sample were recorded as the highest serum dilutions with specific cytoplasmic fluorescence but no fluorescence in the control wells. To evaluate the test, sera of 4 6-week-old pigs that had been infected with SIRS virus, 2 contact pigs, and 13 experimentally infected sows were used. In the experimentally infected pigs, antibody was first detected at 7 days postexposure (PE) and peaked (1:256-1,024) between 11 and 21 days PE. All 13 sow sera were negative at time of infection but were positive (1:64- greater than or equal to 1:1,024) at 14-26 days PE. Seven hundred twenty sera collected from 25 different swine farms with or without a history of SIRS were also tested. Of 344 sera from 15 swine farms with a clinical history of SIRS, 257 (74.7%) sera had IFA titers greater than or equal to 1:4, whereas 371 (98.7%) of 376 sera from herds with no history of SIRS were negative.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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