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341.
This retrospective study evaluated epidemiologic features and disease associations of feline immunodeficiency virus (FIV) infection in client owned cats from western Canada. Among 1205 cats that were tested 66 (5.5%) were positive for FIV antibody (FIV+) with a higher prevalence in males than females. FIV+ cats were older than the overall population. Epidemiologic features and disease associations were compared between 58 FIV+, but feline leukemia virus negative (FeLV) cats and 58 age and sex matched FIV-negative (FIV), FeLV cats. FIV positivity was associated with a history of bite wounds, increasing age, and male gender. Lethargy and oral diseases were significantly associated with FIV positivity. Although several FIV+ cats were euthanized, the survival time of FIV+ cats after diagnosis was not significantly different from that of FIV cats. In summary, FIV prevalence was low in cats from western Canada, clinical signs/diseases were mild, and lifespan was not different in FIV+ cats.  相似文献   
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The effect of natural phenolic acids from wheat bran on type B trichothecene biosynthesis by Fusarium culmorum was investigated in vitro. Durum wheat bran contained various monomeric forms of phenolic acids, with ferulic acid being the most abundant. In addition, various oligomeric forms of ferulic acid and mainly dimeric forms were also detected. When liquid cultures of F. culmorum were supplemented with a natural wheat bran extract, trichothecene production was fully inhibited. The exact mechanism by which toxin synthesis is repressed remains to be clarified but we showed that the phenolic acid treatment resulted in a drastic reduction in the expression level of structural trichothecene biosynthetic genes. The inhibitory efficiency of the natural phenolic acid extract was significantly higher than that of a reconstituted mixture containing similar concentrations of monomeric forms. Thus, to elucidate the full repression of type B trichothecene production induced by the natural phenolic acid extract from wheat bran, two hypotheses can be raised: (i) a synergistic impact of monomeric and dimeric forms of phenolic acids, (ii) the occurrence of an unidentified oligomeric form able to efficiently repress toxin yield. As a first attempt to investigate the effect of oligomeric forms, one of the most abundant dimer of ferulic acid, the 8-5′-benzofuran dimer, has been synthesized in vitro and was shown to inhibit trichothecene biosynthesis to the same extent than the monomer of ferulic acid.  相似文献   
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OBJECTIVE: To evaluate the effects of cyclosporine A in the treatment of sebaceous adenitis in dogs. DESIGN: Open-label clinical trial. ANIMALS: 12 dogs with sebaceous adenitis. PROCEDURE: Dogs were treated with cyclosporine A at a dosage of 5 mg/kg/d (2.3 mg/lb/d), PO, for 12 months and reevaluated every 4 months. A clinical score was calculated by grading the extent of alopecia and severity of follicular casts as absent, mild, moderate, or severe in each of 17 body regions. Biopsy specimens were obtained and examined histologically and by means of immunohistochemical staining. RESULTS: Mean clinical score was significantly decreased, compared with baseline score, after 4 months of treatment and remained low after 8 and 12 months. Histologically, the severity of inflammation was significantly decreased, as were numbers of macrophages, CD3+ T cells, and major histocompatibility complex class II-expressing cells. The percentage of hair follicles with sebaceous glands increased, suggesting regeneration of sebaceous glands. Clinical signs recurred when cyclosporine administration was discontinued. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of cyclosporine A at a dosage of 5 mg/kg/d may reduce the inflammation associated with sebaceous adenitis in dogs. Long-term treatment appears to be neccessary to control the disease.  相似文献   
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The aim of this work was to evaluate the changes in the concentrations, after two rides different for distance covered, of different amino acids in endurance horses. Blood samples have been collected from horses just before the start, at the top of a steep slope (819 m difference in height) and just at the end of a 32-km endurance ride. A second group, competing in a 72 km endurance ride, has also been sampled immediately before and after the race. In serum samples, the concentrations of alanine, arginine, asparagine, glycine, isoleucine, histidine, leucine, lysine, methionine, ornithine, phenylalanine, tryptophan, tyrosine and valine have been measured by high-performance liquid chromatography (HPLC). anova and t-test have been used to study the differences in the concentrations of the amino acids. The pre-ride concentrations of the free amino acids were different between the two races, except for methionine and leucine. Differences between start and end race have been found for both groups for all the considered parameters except asparagine, isoleucine, leucine and lysine for the 72 km ride. Increases have been recorded for the shorter and decreases for the longer ride in the blood serum concentrations. Significant increases have also been found between the starting sampling and the second, at the top of the slope, only for alanine, arginine, asparagines, phenylalanine and lysine. The ride length has a significant impact on blood serum amino acids mobilization and uptake; in the shorter race the increases stand only for mobilization, whereas in the longer the decrease can be considered the effect of the onset of the amino acids catabolism.  相似文献   
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We report the historical, clinical and histopathological characteristics of skin lesions in biopsies from 37 heavy draught horses with chronic pastern dermatitis. The skin lesions were divided into four macroscopic groups: scaling (group I, n=5), hyperkeratotic and hyperplastic plaque-like lesions (group II, n=14), nodular skin masses (group III, n=16) and verrucous skin lesions (group IV, n=2). The principal histological findings were hyperkeratosis and epidermal hyperplasia. There was a gradual increase in epidermal hyperplasia from groups I to IV, suggesting that the lesions represent different stages of disease. In all cases, there was perivascular dermatitis dominated by T lymphocytes with an increase in MHC class II-positive dendritic-like cells. Immunohistochemical labelling for cytokeratins CK5/6(4), CK10 and CK14 indicated a change in their expression pattern. This correlated with the degree of epidermal hyperplasia, indicating abnormal differentiation of keratinocytes. There was a statistically significant correlation between the severity of skin lesions and several other factors including increasing age, increasing cannon circumference, prominence of anatomical structures such as fetlock tufts of hairs, ergots and chestnuts, and bulges in the fetlock region.  相似文献   
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Coronavirus infection of spotted hyenas in the Serengeti ecosystem   总被引:2,自引:0,他引:2  
Sera from 38 free-ranging spotted hyenas (Crocuta crocuta) in the Serengeti ecosystem, Tanzania, were screened for exposure to coronavirus of antigenic group 1. An immunofluorescence assay indicated high levels of exposure to coronavirus among Serengeti hyenas: 95% when considering sera with titer levels of > or = 1:10 and 74% when considering sera with titer levels of > or = 1:40. Cubs had generally lower mean titer levels than adults. Exposure among Serengeti hyenas to coronavirus was also confirmed by a serum neutralisation assay and an ELISA. Application of RT-PCR to 27 fecal samples revealed viral RNA in three samples (11%). All three positive fecal samples were from the 15 juvenile animals (<24 months of age) sampled, and none from the 12 adults sampled. No viral RNA was detected in tissue samples (lymph node, intestine, lung) from 11 individuals. Sequencing of two amplified products from the S protein gene of a positive sample revealed the presence of coronavirus specific RNA with a sequence homology to canine coronavirus of 76 and 78% and to feline coronavirus type II of 80 and 84%, respectively. Estimation of the phylogenetic relationship among coronavirus isolates indicated considerable divergence of the hyena variant from those in European, American and Japanese domestic cats and dogs. From long-term observations of several hundred known individuals, the only clinical sign in hyenas consistent with those described for coronavirus infections in dogs and cats was diarrhea. There was no evidence that coronavirus infection in hyenas caused clinical signs similar to feline infectious peritonitis in domestic cats or was a direct cause of mortality in hyenas. To our knowledge, this is the first report of coronavirus infection in Hyaenidae.  相似文献   
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