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21.
Endoscopic balloon dilation of benign esophageal strictures was performed in 18 dogs and 10 cats with a median age of 4 years. Stricture formation was associated with a recent anesthetic episode in 18 patients. Regurgitation was the most common clinical sign and was present a median of 4 weeks before dilation. Most animals had a single stricture; median diameter was 5 mm, and median length was 1 cm. Esophagitis and mucosal fibrosis were detected in 9 patients each. Dilation was performed with progressively increasing diameter balloons, from 6 to 20 mm. After dilation, mucosal hemorrhage was mild to moderate in most patients. Esophageal perforation was the only serious complication and occurred in 1 patient. Postdilation therapy consisted of administration of cimetidine, metoclopramide, sucralfate, and prednisone in most animals. The median number of dilation procedures performed in each animal was 2, with a range of 1-5. The median interval between dilations was 13 days. Stricture diameter markedly increased with subsequent dilations. Median duration of follow-up was 131 weeks. A successful outcome occurred in 88% of patients, with most animals able to eat canned, mashed, or dry food without regurgitation. Mucosal fibrosis was associated with a better clinical response score, while increasing age was weakly associated with fewer dilations. The dilation protocol used in this group of animals was safe and efficacious.  相似文献   
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Field isolates ( n  = 144) of the wheat take-all fungus Gaeumannomyces graminis var. tritici ( Ggt ) were tested for sensitivity to silthiofam, a take-all-specific fungicide used as a seed treatment, and identified as A- or B-type by PCR–RFLP analysis of nuclear rDNA. A possible association was identified between polymorphisms in ITS2 of the nuclear rDNA and sensitivity to silthiofam. A Ggt -specific PCR assay was developed which simultaneously identified isolates of Ggt as A- or B-type, based on the polymorphisms in the nuclear rDNA. A highly significant correlation between Ggt type using the PCR assay and sensitivity to silthiofam was demonstrated in a collection of 358 isolates from three field experiments designed to test the effects of seed-treatment fungicides on take-all and Ggt populations in winter wheat. In one experiment the percentages of silthiofam-sensitive and B-type isolates were significantly less in populations from plots sown with silthiofam-treated seed in two consecutive years than in populations from plots sown with nontreated seed. However, silthiofam still provided a significant amount of control of take-all. The natural occurrence of fungicide-insensitive isolates, up to about 30% in soils in which the fungicide had never been used, is unusual. The new PCR assay provides a useful tool for studying the population structure of Ggt , and may provide a novel method for assessing the incidence of insensitivity to silthiofam (the target site for which has not yet been identified) in field populations of Ggt .  相似文献   
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OBJECTIVE: To test whether injecting lignocaine into the scrotal neck 5 to 10 s before or into both testes immediately after ring castration and docking wound significantly reduce the plasma cortisol response to castration and docking. DESIGN: A physiological study with controls. PROCEDURE: Lambs were given one of six treatments: control handling, injection of lignocaine into scrotal neck, injection of lignocaine into both testes, ring castration and docking, ring castration and docking after lignocaine was injected into the scrotal neck, and ring castration and docking before lignocaine was injected into both testes. Blood samples were taken before and regularly after treatment and analysed for plasma cortisol concentrations. RESULTS: The plasma cortisol concentrations of lambs castrated and docked after lignocaine had been injected into the scrotal neck were significantly lower between 20 and 60 min after treatment than in lambs castrated and docked without local anaesthesia. Injecting lignocaine into the testes after ring application did not significantly reduce the cortisol response to ring castration and docking. CONCLUSIONS: Lignocaine injected into the scrotal neck 5 to 10 s before ring castration will reduce the cortisol response and by inference the pain associated with ring castration.  相似文献   
25.
A pure growth of Group Eugonic Fermenter-4 bacteria (gram-negative) was isolated from the lungs of an 11-year-old male domestic cat that had been ill for 2 days before death. Clinical signs included anorexia, severe dyspnea, and salivation. The lungs contained several firm, slightly raised, yellowish-gray, spherical nodules of various sizes. Purulent exudate was found in the pericardial sac and left pleural cavity. Histologic evaluation revealed multifocal suppurative pneumonia.  相似文献   
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Shared antigens between Mycoplasma arthritidis and rat tissues may be responsible for the lack of metabolism-inhibition (MI) and other neutralizing antibodies in rats with M arthritidis-induced arthritis. We were not able to confirm such antigens or to detect cross-reacting antigens between M arthritidis and rat lymphocytes, thymocytes, and muscle tissue. Antisera of rabbit origin to rat lymphocytes, thymocytes, and skeletal muscle reacted by ELISA with M arthritidis only when the mycoplasmal antigens were prepared from organisms grown in medium containing horse serum. Such activity could be completely absorbed by horse serum. These antisera to rat tissues also failed to react by radioimmunoprecipitation with M arthritidis surface antigens. In addition, antibody activity against homologous antigens could not be absorbed by M arthritidis. Similarly, antisera of rabbit origin against M arthritidis failed to react by ELISA specifically with rat lymphocytes, thymocytes, and skeletal muscle or to react by radioimmunoprecipitation with 125I-labeled rat lymphocyte antigens. These rat tissues could not specifically absorb antibodies against M arthritidis from antisera of rabbit origin. These findings suggest that the lack of MI antibodies in rats probably can not be explained by rat tissue antigens that cross-react with M arthritidis MI antigens. Finally, antisera of rat origin against M arthritidis and other rat tissue components failed to block rabbit MI activity against M arthritidis, thus arguing against steric hindrance as a means of preventing recognition of MI antigens.  相似文献   
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Pulmonary pathology of the motheaten mouse   总被引:7,自引:0,他引:7  
Mice, homozygous for the motheaten gene, developed an unusual pneumonia that was the cause of natural death of mice by 7 weeks of age. Initial lesions consisted of focal accumulations of alveolar macrophages in alveoli, especially adjacent ot bronchioles. Needle-like crystals formed in lysosomes of macrophages and numerous macrophages with crystals filled most alveoli in 5- to 7-week-old mice. Although motheaten mice had lesions in other tissues and were shown by other investigators to have immunological defects, the unusual pneumonia was the only lesion severe enough to cause death.  相似文献   
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OBJECTIVE: To determine the effects of endotoxin administration on thyroid function test results and serum tumor necrosis factor-alpha (TNF-alpha) activity in healthy dogs. ANIMALS: 6 healthy adult male dogs. PROCEDURES: Serum concentrations of thyroxine (T4), 3,5,3'-triiodothyronine (T3), 3,3'5'-triiodothyronine (rT3), free T4 (fT4), and endogenous canine thyroid stimulating hormone (TSH), and TNF-alpha activity were measured before (day-1; baseline), during (days 0 to 3), and after (days 4 to 24) IV administration of endotoxin every 12 hours for 84 hours. RESULTS: Compared with baseline values, serum T3 concentration decreased significantly, whereas rT3 concentration increased significantly 8 hours after initial endotoxin administration. Serum T4 concentration decreased significantly at 8 and 12 hours after initiating endotoxin administration. Serum T4 concentration returned to reference range limits, then decreased significantly on days 6 to 12 and 16 to 20. Serum fT4 concentration increased significantly at 12, 24, and 48 hours after cessation of endotoxin treatment, compared with baseline values. Serum rT3 concentration returned to reference range, then decreased significantly days 5 and 7 after stopping endotoxin treatment. Serum TNF-alpha activity was significantly increased only 4 hours after initial endotoxin treatment, compared with baseline activity. CONCLUSIONS AND CLINICAL RELEVANCE: Endotoxin administration modeled alterations in thyroid function test results found in dogs with spontaneous nonthyroidal illness syndrome. A decrease in serum T4 andT3 concentrations and increase in serum rT3 concentration indicate impaired secretion and metabolism of thyroid hormones. The persistent decrease in serum T4 concentration indicates that caution should be used in interpreting serum T4 concentrations after resolution of an illness in dogs.  相似文献   
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