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51.
A commercially available absorbed ELISA for the diagnosis of Johne's disease (JD) (paratuberculosis) in cattle, the Johne's Absorbed EIA, was compared with the conventional complement-fixation test (CFT) used in Australia. Stored plasma from 3 Victorian dairy herds with a history of JD, sera from specimens submitted from animals showing clinical signs of JD and sera from the US National Repository for Paratuberculosis Specimens were used to determine the sensitivity of each test. The EIA detected 48.8% of 43 Australian animals with subclinical JD, while the CFT detected only 12 (21.4%) of 56 subclinically affected cattle. Of 150 subclinically infected US cattle, the EIA detected 47.3% and the CFT detected 52.0%. The EIA detected 59.7% of animals which at the time of sampling were shedding Mycobacterium paratuberculosis in their faeces, but showed no clinical signs of JD, while the CFT detected 57.3%. The EIA correctly identified 88.2% of 136 histologically confirmed clinical cases, and the CFT detected 83.4%. The specificity of each test was determined by testing sera collected at slaughter from animals residing in a known JD-free area of Australia, and from samples from the US National Repository of Paratuberculosis Specimens collected from certified-free herds in Wisconsin. The EIA was found to have a specificity of 99.8% when 998 Australian animals were used as the test population, and 99.0% when 196 US animals were used. The specificity of the CFT using Australian samples was 96.9% and 95.2% using American samples.  相似文献   
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A study was conducted to document the maximum retention times of antimicrobial residues in milk after their use in intrauterine treatment of metritis in lactating cows and to evaluate several risk factors hypothesized to influence the retention time of these drugs. Oxytetracycline (3 g), lincomycin-spectinomycin (2 g of one-third lincomycin and two-thirds spectinomycin), or povidone-iodine (6 g) were given to cows with metritis by intrauterine route. The Bacillus stearothermophilus var calidolactis disk assay was performed on each milk sample. Of the 61 cows treated with oxytetracycline, 30 had residues in their postinjection milk for variable periods (range, 12.5 to 44.0 hours; mean, 26.6 +/- 10.3). Of the 47 cows treated with lincomycin-spectinomycin, 17 had residues in their postinjection milk for various periods (range, 14.5 to 24 hours; mean, 19.5 +/- 8.9). Povidone-iodine was not detected in milk. Because a high number of cows (n = 61) were treated with oxytetracycline, only data from these cows were used in testing the influence of 3 factors (severity of metritis, time after parturition when cows with metritis were treated, and parity) on maximum retention of the drug in milk. Severity of metritis did not have a significant influence (P greater than or equal to 0.1) on the maximum retention time of the drug. The retention time decreased linearly with the increase of time after parturition when the cow with metritis was treated. First lactation cows had a significantly (P less than or equal to 0.01) shorter retention time than did older cows.  相似文献   
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Gastrointestinal foreign bodies occur commonly in dogs. The objective of the study was to describe the acid-base and electrolyte abnormalities identified in dogs with gastrointestinal foreign bodies and determine if these abnormalities are related to the site or type of foreign body present. Medical records of 138 dogs were reviewed, and information on signalment, initial venous electrolyte and acid-base values, surgical findings, relevant historical information, imaging modalities used, cost of hospital visit, intra- or postoperative complications, and survival was obtained. The site of the foreign body was recorded in 94.9% of cases and the most common site was the stomach (50%), followed by the jejunum (27.5%). The foreign bodies were linear in 36.2% of cases. The most common electrolyte and acid-base abnormalities regardless of the site or type of foreign body were hypochloremia (51.2%), metabolic alkalosis (45.2%), hypokalemia (25%), and hyponatremia (20.5%). No significant association was found between electrolyte or acid-base abnormalities and the site of foreign body. Linear, as opposed to discrete, foreign bodies were more likely to be associated with a low serum sodium concentration (odds ratio, 0.85; 95% confidence interval, 0.75-0.95). Hyperlactatemia (> 2.4 mmol/L) was seen in 40.5% of dogs. A wide variety of electrolyte and acid-base derangements are found in dogs with gastrointestinal foreign bodies. Hypochloremia and metabolic alkalosis are common in these dogs. Hypochloremic, hypokalemic metabolic alkalosis is seen with both proximal and distal gastrointestinal foreign bodies.  相似文献   
55.
OBJECTIVES: The incidence of urinary incontinence due to urethral sphincter mechanism incompetence (USMI) in male dogs is relatively rare compared with the incidence in bitches, but the medical management of USMI in male dogs is less rewarding than in bitches. Attempts have been made to manage this condition surgically using either urethral bulking agents such as Teflon or by relocating the intrapelvic bladder neck to an intra-abdominal position by vas deferentopexy. This paper reports the response to prostatopexy in male dogs with USMI. METHODS: The response to prostatopexy was determined in nine severely incontinent male dogs with USMI that were followed up for periods ranging from 10 months to five years (mean 2.3 years). RESULTS: One dog was cured, four were improved, and no improvement in the frequency or degree of urinary incontinence occurred in the remaining four animals. No complications were seen in any of the dogs. CLINICAL SIGNIFICANCE: Prostatopexy may provide a further method of treating male dogs with USMI that do not respond to medical therapy.  相似文献   
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A block with a hitherto unknown system of writing has been found in the Olmec heartland of Veracruz, Mexico. Stylistic and other dating of the block places it in the early first millennium before the common era, the oldest writing in the New World, with features that firmly assign this pivotal development to the Olmec civilization of Mesoamerica.  相似文献   
60.
Mesothelioma has been reported frequently in large felids. These neoplasms present a diagnostic challenge given their highly variable morphology that mimics carcinomas or sarcomas at different locations. Our goal was to characterize mesotheliomas morphologically and immunohistochemically to determine if a panel of antibodies could be used to more accurately support the diagnosis of these neoplasms in large felids. Mesotheliomas from 6 large felids, including 4 clouded leopards, 1 Bengal tiger, and 1 cheetah, were immunohistochemically labeled for vimentin, E-cadherin, pancytokeratin, Wilms tumor 1 (WT1), MUC-1, and calretinin. The mesotheliomas of the 4 clouded leopards and the tiger were of the epithelial subtype; the mesothelioma from the cheetah was biphasic. All 6 mesotheliomas had strong immunohistochemical labeling for vimentin, E-cadherin, and pancytokeratin. All cases had cytoplasmic labeling for WT1, and 2 also had nuclear labeling. The 3 mesotheliomas with distinct papillary fronds were weakly positive for MUC-1. These and one other epithelial mesothelioma were also positive for calretinin. Our study demonstrates that the morphologic and immunohistochemical phenotypes of mesothelioma that have been identified in humans and domestic species can occur in large felids, and a panel of pancytokeratin, vimentin, WT1, and calretinin can be utilized to support the diagnosis of these neoplasms.  相似文献   
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