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11.
PJ Kelly CT McDonald GO Neill C Thomas J Niles G Rordorf 《Canadian Metallurgical Quarterly》1998,50(4):1157-1160
Idiopathic thrombotic thrombocytopenic purpura (TTP) is frequently complicated by microinfarcts in cerebral cortex and subcortical white matter. We describe two sisters who suffered massive hemispheric infarction due to thrombosis of the middle cerebral artery main stem during exacerbations of TTP. Acute TTP may be associated with intraluminal thrombosis of large-diameter arteries in addition to arterioles and capillaries. 相似文献
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GO Aspinall AG McDonald H Pang LA Kurjanczyk JL Penner 《Canadian Metallurgical Quarterly》1993,268(24):18321-18329
A water-soluble antigenic polysaccharide of high M(r) associated with the lipopolysaccharide has been isolated from phenol-water extraction of cells of Campylobacter coli serotype O:30. The polysaccharide and oligosaccharide degradation products formed on O-dephosphorylation and by periodate oxidation followed by reduction have been investigated by one- and two-dimensional 1H, 13C, and 31P NMR. It is concluded that the antigenic polysaccharide has a teichoic acid-like structure with a poly-Ribitol phosphate, [5-Ribitol-1-P]n, backbone with side chains at O-2 of O-(6-deoxy-beta-D-talo-heptopyranosyl)-(1-->4)-(2-acetylamino-2-deoxy-beta-D- glucopyranosyl) units. The structure is unusual in Gram-negative bacteria and is unique in possessing 6-deoxy-D-talo-heptose as a constituent sugar. Evidence for the relationship of the antigenic polysaccharide to the lipopolysaccharide of low M(r) is discussed. 相似文献
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A single randomized trial evaluated the use of intravenous cyclosporine treatment for severe attacks of ulcerative colitis. The perceived efficacy and safety of this intervention were measured through a survey of the membership of the Canadian Association of Gastroenterology (CAG). METHODS: All CAG members were mailed a survey with questions regarding their familiarity with the data supporting the use of cyclosporine, their perception of the efficacy and toxicity of the drug, and whether patients who fail conventional treatment should receive this therapy. The proportion of respondents who had used cyclosporine to treat severe ulcerative colitis was determined. RESULTS: One hundred and sixty-one responses were received (34% response rate). Sixty-four per cent of respondents were academic faculty members and 82% treated patients with severe colitis. Using multivariate analyses, positive associations were found between the respondents' age (P = 0.004) and subspecialty training in gastroenterology (P = 0.001), and whether respondents treat patients with severe ulcerative colitis. Twenty-six per cent of individuals had prescribed cyclosporine for this indication, of whom 88% were in academic practice (P = 0.007). Over 90% of respondents believe that further clinical trials are needed before cyclosporine becomes accepted as standard therapy. CONCLUSIONS: Although the use of cyclosporine is measurable among Canadian gastroenterologists, the majority believe that further clinical trials are necessary before the drug is accepted as a standard therapy. 相似文献
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Our previous receiver operating characteristic (ROC) study indicated that the detection accuracy of microcalcifications by radiologists is significantly reduced if mammograms are digitized at 0.1 mm x 0.1 mm. Our recent study also showed that detection accuracy by computer decreases as the pixel size increases from 0.035 mm x 0.035 mm. It is evident that very large matrix sizes have to be used for digitizing mammograms in order to preserve the information in the image. Efficient compression techniques will be needed to facilitate communication and archiving of digital mammograms. In this study, we evaluated two compression techniques: full frame discrete cosine transform (DCT) with entropy coding and Laplacian pyramid hierarchical coding (LPHC). The dependence of their efficiency on the compression parameters was investigated. The techniques were compared in terms of the trade-off between the bit rate and the detection accuracy of subtle microcalcifications by an automated detection algorithm. The mean-square errors in the reconstructed images were determined and the visual quality of the error images was examined. It was found that with the LPHC method, the highest compression ratio achieved without a significant degradation in the detectability was 3.6:1. The full frame DCT method with entropy coding provided a higher compression efficiency of 9.6:1 at comparable detection accuracy. The mean-square errors did not correlate with the detection accuracy of the microcalcifications. This study demonstrated the importance of determining the quality of the decompressed images by the specific requirements of the task for which the decompressed images are to be used. Further investigation is needed for selection of optimal compression technique for digital mammograms. 相似文献
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TL Tomusiak FI Mamchur NV Zeliak LT Kisilevich ZR Matsun IN Gurvits 《Canadian Metallurgical Quarterly》1993,(3):11-13
Long-term (1-10 years) results of wandering kidney surgery were followed-up for 118 patients. The outcomes were found dependent on the duration of the disease, variety and severity of the lesion, age of the patients. The response appeared better in younger patients, in those with shorter duration of the disease and with unessential changes in the kidney. Recommendations are provided on the regimens, jobs, outpatient and inpatient follow-up for the subjects treated surgically for wandering kidney to reinforce the correction results achieved. 相似文献
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Jayaweera D. Galloway S. Burt G. McDonald J.R. 《Power Systems, IEEE Transactions on》2007,22(2):514-521
This paper proposes an innovative way of making a decision to island (or synchronize) distributed generators when operating conditions of a distribution system are varied. Islanding decisions are made when a network undergoes disturbances. In this approach, there is a decision-making mechanism, which samples states of the network operating condition to either synchronize or island in an identified period of time. Decision making is achieved through extended sequential sampling, which manages generator states within specific time periods. The approach can minimize the duration of islanded operation and manage generators' re-connection to the grid. Use of the proposed mechanism and sampling approach offer benefits over conventional relays; incorrect operations due to errors in measurements are reduced because the operational actions are not based on a single decision sample, but instead rely on extended sequential sampling over a number of samples. A case study is investigated using the IEEE 30-bus test system and the results are presented for this new approach 相似文献
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In their public statements, politicians and leaders of mostdeveloped countries espouse the doctrine that the growth oftheir respective economies is highly dependent on innovationsresulting from scientific research and development. Many countriessupport science directly or indirectly using a variety of subsidies,grants, contracts, or other financial mechanisms. But, the lion'sshare of support for research and development is usually providedby industry. The statistic often quoted is the percentage ofgross domestic product 相似文献
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