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Samples of 79 black paints from 27 manufacturers in the United States were examined to determine the extent to which paints can be distinguished by pyrolysis-gas chromatography. Evaluation by a Carbowax column showed some differences among paints from different manufacturers and among batches of paints from the same manufacturer. However, it was not possible to conclude that paints with identical chromatograms had a common origin.  相似文献   
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Bluetongue (BT) is an insect transmitted viral disease of sheep that often causes mild or inapparent disease but rarely causes severe disease in cattle. Until recently, bluetongue viral infection was believed to be more prevalent in the Western United States, as compared with other regions of the country. However, a national survey for bluetongue antibody and clinical evidence of the disease in the Southeastern United States prompted the present investigation that was designed to determine the serological prevalence of BT virus in Alabama cattle. Results of the study demonstrated that 16% of the samples collected from 1,500 cattle in 64 of the 67 counties were positive. The prevalence of positive cattle in the western part of the State was significantly higher (P less than .001) than the prevalence in the eastern half of the State. On a herd basis, 52% of all herds tested had positive animals. Results of this study suggest that bluetongue infection is more common in the Southeastern United States than previously suspected.  相似文献   
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The in vitro effects of prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), indomethacin, histamine, and tuftsin on the chemiluminescence response of bovine polymorphonuclear cells (PMN) were determined. Addition of PGE1, PGE2, indomethacin, and histamine in vitro significantly suppressed the chemiluminescence response of bovine PMN's, whereas tuftsin had no effect. Suppression was dependent upon the continued presence of PGE1, PGE2, and histamine in the culture media. However, indomethacin's suppressive effect remained even after it was removed from the culture media. Hydrogen peroxide generated chemiluminescence was suppressed by high concentrations of indomethacin and histamine. Results of this study suggest possible pharmacologic or regulatory mechanisms for certain of these immune modulators in the control of the oxidative burst reaction of bovine PMN's.  相似文献   
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Toxoplasma gondii is a zoonotic protozoan pathogen that infects many endothermic vertebrates, including humans; the domestic cat and other felids serve as the definitive host. Macropodids are considered highly susceptible to toxoplasmosis. Here, we describe the clinical, pathologic, and immunohistochemical findings of an outbreak of systemic toxoplasmosis in a mob of 11 red kangaroos (Macropus rufus), with high morbidity (73%) and mortality (100%) rates. Affected animals had either severe and rapidly deteriorating clinical conditions or sudden death, which was correlated with widespread necrotizing lesions in multiple organs and intralesional T. gondii organisms identified via MIC3-specific immunohistochemistry and confirmed by REP529-specific rtPCR. Quantification of parasites demonstrated the highest parasite density in pulmonary parenchyma compared with other tissues. Our study highlights the continued importance of this severe condition in Australian marsupials.  相似文献   
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