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Gillian D Alton David L Pearl Ken G Bateman W Bruce McNab Olaf Berke 《BMC veterinary research》2010,6(1):42
Background
Ontario provincial abattoirs have the potential to be important sources of syndromic surveillance data for emerging diseases of concern to animal health, public health and food safety. The objectives of this study were to: (1) describe provincially inspected abattoirs processing cattle in Ontario in terms of the number of abattoirs, the number of weeks abattoirs process cattle, geographical distribution, types of whole carcass condemnations reported, and the distance animals are shipped for slaughter; and (2) identify various seasonal, secular, disease and non-disease factors that might bias the results of quantitative methods, such as cluster detection methods, used for food animal syndromic surveillance. 相似文献2.
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G Majmudar E Schalk J Bateman B Peterkofsky 《The Journal of biological chemistry》1988,263(12):5555-5559
Syrian hamster embryo fibroblasts transformed by 4-nitroquinoline-1-oxide (NQT-SHE cells) failed to synthesize the pro-alpha 1(I) subunit of type I procollagen but continued to synthesize altered forms of the other subunit, pro-alpha 2(I) (Peterkofsky, B., and Prather, W. (1986) J. Biol. Chem. 261, 16818-16826). This was unusual, since synthesis of the two subunits generally is coordinately regulated. Present experiments using cell-free translation and hybridization of RNA from normal and transformed Syrian hamster fibroblasts with labeled pro-alpha 1(I) DNA probes show that mRNA for pro-alpha 1(I) is absent from the transformant. In contrast, dot-blot and Southern blot hybridizations of cellular DNAs with pro-alpha 1(I) DNA probes demonstrated that the transformed cells contained pro-alpha 1(I) gene sequences and that the gross structure of the gene was unchanged by transformation. mRNA for the other type I procollagen subunit, pro-alpha 2(I), was present in transformed cells and the major collagenous polypeptide translated from this RNA migrated like the normal pro-alpha 2 subunit during sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The translated procollagen chain was cleaved to an alpha 2(I)-sized collagen chain by pepsin at 4 degrees C. These studies provide a molecular basis for the observed collagen phenotype of NQT-SHE cells. 相似文献