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31.
R Rabinowitz M Barkin JF Schillinger RD Jeffs GT Cook 《Canadian Metallurgical Quarterly》1977,118(3):436-439
Bypass of the left ventricle was accomplished in dogs and the entire circulation was supported temporarily by only the right ventricle. The atrial septum was excised, and the atrium was repartitioned so that the pulmonary veins were in continuity with the right ventricle and the venae cavae were connected through the atrium. Anastomosis of the superior vena cava to the right pulmonary artery brought systemic venous return directly to the lungs. The main pulmonary artery was ligated proximal to the bifurcation, preserving distal confluence of right and left pulmonary arteries. A tubular prosthesis between the proximal pulmonary artery and the aorta connected the right ventricle to the systemic circuit. This procedure, or some modification of the principle, may have clinical feasibility in the treatment of patients with hypoplastic left heart syndrome. 相似文献
32.
The first case of the unstable Hb Genova as a result of sporadic mutation is described. It is found in a 3-year-old Canadian boy of East Indian extraction with chronic Heinz body haemolytic anaemia. 相似文献
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SD Gettings RA Lordo KL Hintze DM Bagley PL Casterton M Chudkowski RD Curren JL Demetrulias LC Dipasquale LK Earl PI Feder CL Galli SM Glaza VC Gordon J Janus PJ Kurtz KD Marenus J Moral WJ Pape KJ Renskers LA Rheins MT Roddy MG Rozen JP Tedeschi J Zyracki 《Canadian Metallurgical Quarterly》1996,34(1):79-117
The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data. 相似文献
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RD Rosenberg WC Hunt MR Williamson FD Gilliland PW Wiest CA Kelsey CR Key MN Linver 《Canadian Metallurgical Quarterly》1998,209(2):511-518
PURPOSE: To examine how common patient factors affect screening mammographic sensitivity and cancer stage at diagnosis. MATERIALS AND METHODS: The authors used a population-based database of 183,134 screening mammograms and a statewide tumor registry to identify 807 breast cancers detected at screening mammography. RESULTS: Sensitivity varied significantly with ethnicity, use of estrogen replacement therapy, mammographic breast density, and age. Sensitivity was 54% (13 of 24) in women younger than 40 years, 77% (121 of 157) in women aged 40-49 years, 78% (224 of 286) in women aged 50-64 years, and 81% (277 of 340) in women older than 64 years. Sensitivity was 68% (162 of 237) for dense breasts and 85% (302 of 356) for nondense breasts and 74% (180 of 244) in estrogen replacement therapy users and 81% (417 of 513) in nonusers. Sensitivity was most markedly reduced with the combination of dense breasts and estrogen replacement therapy use; there was little difference when only one factor was present. Median cancer size and the percentage of early cancers showed little change with any factors. CONCLUSION: Age is a minor determinant of mammographic sensitivity in women aged 40 years or older. Sensitivity is substantially decreased with the combination of higher breast density and estrogen replacement therapy use. There was not a notable shift in cancer outcomes in the groups with lower mammographic sensitivity. These data do not support different screening recommendations in women aged 40-49 years or in estrogen replacement therapy users. 相似文献
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RD Kortschak H Reimann M Zimmer HJ Eyre R Saint DE Jenne 《Canadian Metallurgical Quarterly》1998,51(2):288-292
A 2-year trial was conducted to evaluate the cost-effectiveness of heliotherapy for psoriasis. The course and cost of psoriasis of 46 Finnish patients were first closely monitored for 1 year, then the patients received a 4-week supervised heliotherapy treatment in the Canary Islands, Spain, after which they continued to be followed for another year. Heliotherapy dramatically reduced the severity of psoriasis and also seemed to have favourable long-term effects on psoriasis. The mean direct cost of the 4-week heliotherapy for one patient was FIM12,289 (1 Pound = FIM7.0 in 1989). The cost of flights and half-board in Spain formed nearly 60% (FIM7033) of the total cost. In the year preceding heliotherapy, the mean direct annual cost of antipsoriasis therapy was FIM7335 and in the year after FIM5700, a reduction of 22% in annual costs; this change was not statistically significant because there were large variations in costs among patients. The costs of heliotherapy exceeded manyfold the mean monthly cost of conventional psoriasis therapy. There were no overall savings using heliotherapy in those patients suffering mainly from moderately severe psoriasis. Heliotherapy saved costs only in those patients with severe psoriasis that required expensive medication or ward treatment. Although heliotherapy cannot be regarded as an economical treatment for the average patients with psoriasis, it clears psoriasis effectively and is preferred by patients. Thus, heliotherapy constitutes an alternative for patients suffering severe psoriasis. 相似文献
38.
JM Larner H Lee RD Little PA Dijkwel CL Schildkraut JL Hamlin 《Canadian Metallurgical Quarterly》1999,27(3):803-809
An asynchronous culture of mammalian cells responds acutely to ionizing radiation by inhibiting the overall rate of DNA replication by approximately 50% for a period of several hours, presumably to allow time to repair DNA damage. At low and moderate doses, this S phase damage-sensing (SDS) pathway appears to function primarily at the level of individual origins of replication, with only a modest inhibition of chain elongation per se. We have shown previously that the majority of the inhibition observed in an asynchronous culture can be accounted for by late G1cells that were within 2-3 h of entering the S period at the time of irradiation and which then fail to do so. A much smaller effect was observed on the overall rate of replication in cells that had already entered the S phase. This raised the question whether origins of replication that are activated within S phase per se are inhibited in response to ionizing radiation. Here we have used a two-dimensional gel replicon mapping strategy to show that cells with an intact SDS pathway completely down-regulate initiation in both early- and late-firing rDNA origins in human cells. We also show that initiation in mid- or late-firing rDNA origins is not inhibited in cells from patients with ataxia telangiectasia, confirming the suggestion that these individuals lack the SDS pathway. 相似文献
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OBJECTIVE AND IMPORTANCE: We present a case report of a patient with a left frontal brain abscess. Cultures obtained from the abscess at the time of surgery were identified as dental flora known to establish a synergistic relationship in polymicrobial infections. This type of synergistic relationship makes the clearance of an infection more difficult for an intact immune system. A serum immunoglobulin (Ig) Type A deficiency was identified postoperatively. This immunodeficiency may have contributed to the development of the abscess. CLINICAL PRESENTATION: The patient presented with headaches and photophobia. Computed tomography of the head performed with intravenously administered contrast demonstrated a left frontal brain abscess. INTERVENTION: The patient was operated on through a left frontal approach, carefully avoiding the frontal sinus. The abscess was aspirated, and the patient was treated with intravenous antibiotics for several weeks. Postoperatively, the patient did well. There were no signs of enhancement on follow-up computed tomographic scans at 7 and 12 months postoperatively. CONCLUSION: Through a comprehensive immunological workup, an IgA deficiency was identified postoperatively. Although the deficiency of a single type of Ig may be asymptomatic, complications from recurrent or chronic bacterial infections may occur. The deficiency of IgA, combined with a synergistic polymicrobial infection, contributed to the development of an intracranial abscess. A patient presenting with a brain abscess without any predisposing medical history should be evaluated for an underlying immune deficiency. 相似文献
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