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71.
HG Garrison GL Foltin LR Becker JL Chew M Johnson GM Madsen DR Miller BH Ozmar 《Canadian Metallurgical Quarterly》1997,1(3):156-162
Recent studies have shown a high frequency of genetic hemochromatosis in the Caucasian population. In addition, the well known organ involvement of genetic hemochromatosis was evident; more than 50% of patients develop a typical arthropathy which may result in severe physical disability. Among approximately 5000 patients referred to the rheumatology outpatient clinics of Bad Nauheim and Frankfurt with different rheumatologic diagnoses, 11 patients with typical signs of hemochromatotic arthropathy were identified. In none of those cases had the diagnosis "genetic hemochromatosis" been previously established. These patients had been treated for rheumatoid arthritis and other rheumatologic disorders over several years. All showed severe organ dysfunction due to iron overload, resulting in a reduced life expectancy. This investigation shows that knowledge of the typical signs of hemochromatotic arthropathy could lead to an earlier diagnosis of genetic hemochromatosis which is necessary to prevent the complications of iron overload in those patients. 相似文献
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GM Bisset V Bavetsias TJ Thornton K Pawelczak AH Calvert LR Hughes AL Jackman 《Canadian Metallurgical Quarterly》1994,37(20):3294-3302
Sixteen gamma-linked dipeptide and four L-Glu-gamma-amide analogues of 2-desamino-2-methyl-N10-propargyl-5,8-dideazafolic acid (ICI 198583) have been synthesized and evaluated as inhibitors of thymidylate synthase (TS). Z-blocked L-Glu-gamma-L-linked dipeptides and L-Glu-gamma-amides were prepared by condensing alpha-tert-butyl-N-(benzyloxycarbonyl)-L-glutamic acid with the appropriate tert-butyl-protected L-amino acid or amine. The Z group was removed by catalytic hydrogenolysis, and the resulting dipeptides or L-Glu-gamma-amides were condensed with the appropriate pteroic acid analogue trifluoroacetate salt using diethyl cyanophosphoridate as coupling reagent. Deprotection with trifluoroacetic acid in the final step gave the desired quinazoline gamma-linked dipeptides and L-Glu-gamma-amides as their trifluoroacetate salts. Nearly all the dipeptide analogues were potent inhibitors of TS, the best being ICI 198583-gamma-L-2-aminoadipate (IC50 = 2 nM). Several of these dipeptides were found to be susceptible to enzymatic hydrolysis in mice. The quinazoline monocarboxylate L-Glu-gamma-amides, lacking an alpha'-carboxyl group, are less active against TS and L1210 cell growth but are also not susceptible to enzymatic hydrolysis in mice. 相似文献
75.
Epstein-Barr virus (EBV) is associated with the development of several B cell malignancies including Burkitt's lymphoma (BL), post-transplant lymphoproliferative disease (PTLD), and AIDS-related lymphomas. The latter two diseases result from EBV-driven B cell proliferation in the absence of normal immunosurveillance and as such, represent a heterogenous family of lymphoproliferative disorders. This article reviews studies on EBV gene expression and antibody development in PTLD and introduces recent information on the levels of EBV+ peripheral blood lymphocytes to discuss possible mechanisms of pathogenesis under varying conditions of immunosuppression. 相似文献
76.
LR Farber LR Prosnitz EC Cadman R Lutes JR Bertino DB Fischer 《Canadian Metallurgical Quarterly》1980,46(7):1509-1517
During the period from 1969 through 1977, 124 patients with advanced Hodgkin's disease underwent treatment with combination chemotherapy and radiotherapy. Sixty-three cases were previously untreated, and 61 were relapses following radical radiotherapy for localized Hodgkin's disease. No patient in this series had received prior chemotherapy. Of 102 patients (84%) who have entered complete remission, 92 remain in complete remission with a median follow up time of five years, 10 patients having relapsed, and acute leukemia having developed in 2. The cumulative survival rate for all 124 patients is 80% at five years; the relapse-free survival rate is 74%. In many, if not most cases, the Hodgkin's disease appears to be cured. We have also identified two subgroups of patients for whom the prognosis is worse than for patients with advanced-stage disease as a whole. Patients over the age of 40 years have a five-year survival rate of only 45%, compared with 89% for all other patients. Those Stage IV patients with multiple extranodal sites of involvement have a five-year survival rate of 48%, compared with 81% for other Stage IV patients with only a single extranodal site involved. 相似文献
77.
MJ van den Brand A van Miltenburg MJ de Boer LR van der Wieken PJ de Feyter ML Simoons 《Canadian Metallurgical Quarterly》1994,10(3):177-185
Patients with unstable angina, refractory to intensive medical therapy, are at high risk for developing thrombotic complications, such as recurrent ischemia, myocardial infarction and coronary occlusion during coronary angioplasty. As both platelet aggregation and/or thrombus formation play an important role in this ongoing ischemic process, a monoclonal platelet GPIIb/IIIa receptor antibody (c7E3) or thrombolytic therapy (alteplase) might be able to modify the clinical course and underlying coronary lesion morphology. To evaluate whether alteplase or c7E3 could influence the incidence of complications, we randomized 36 and 60 patients, respectively to alteplase or placebo, or c7E3 or placebo. All patients exhibited dynamic ECG changes and recurrent pain attacks, despite maximal tolerated medical therapy. Patients were randomized in both studies after initial angiography had demonstrated a culprit lesion amenable for angioplasty. After study drug infusion quantitative angiography was repeated and angioplasty performed. Recurrent ischemia during study drug infusion occurred in 5, 6, 9 and 16 patients from the alteplase, placebo, c7E3 and placebo group, respectively. Major events defined as death, myocardial infarction or urgent intervention occurred in 7, 3, 1 and 7 patients, respectively. Two patients died: one in the alteplase group and one in the placebo group from the c7E3 study. The first patient due to retroperitoneal hemorrhage, the second as a result of recurrent infarction. Qualitative angiography showed resolution of clots in the c7E3 group only, while the same group of patients showed in 20% an improvement in TIMI flow grade, without deterioration in any patient from this group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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LR Margraf 《Canadian Metallurgical Quarterly》1996,16(1):155-160
The prognostic value of p53 protein in tumor extracts as measured by ELISA was studied retrospectively in 228 non-small cell lung cancer (NSCLC) patients. The assay measures both wild-type and mutated p53. The specimens on which this study was performed have been used earlier to analyze the prognostic impact of components of the plasminogen activation system, which enabled an analysis of relationships between these components and p53 protein. The median of the p53 protein values in the 228 patients was 0.10 (range, 0-0.70) ng/mg protein. Survival analysis comparing patients with p53 levels below versus above the median showed no significant difference (P = 0.67). When analyzing the histological types, adenocarcinoma (n = 106), squamous cell carcinoma (n = 84), and large cell carcinoma of the lung (n = 38) separately, similarly, no significant differences in survival between patients having low versus high tumor p53 levels were found. When comparing levels of p53 protein in the three histological types, a significant difference (P < 0.0001) was found, with adenocarcinomas having the lowest levels. There was a weak positive correlation (r = 0.22) between p53 protein and plasminogen activator inhibitor type 1 (PAI-1). Multivariate analysis proved no impact of p53 on survival; tumor size, PAI-1, and lymph node involvement were the only variables with significant influence on survival. These data indicate that p53 protein quantitated with a sandwich ELISA in tumor extracts from NSCLC has no prognostic value, but the observed statistically significant difference of p53 protein content between histological subgroups may be related to differences in etiology and biology in different NSCLC subtypes. In addition, the weak association found between p53 protein and the independent prognostic marker PAI-1 could suggest yet undefined interactions in lung cancer. 相似文献
80.
A neostriatal habit learning system in humans 总被引:1,自引:0,他引:1
Amnesic patients and nondemented patients with Parkinson's disease were given a probabilistic classification task in which they learned which of two outcomes would occur on each trial, given the particular combination of cues that appeared. Amnesic patients exhibited normal learning of the task but had severely impaired declarative memory for the training episode. In contrast, patients with Parkinson's disease failed to learn the probabilistic classification task, despite having intact memory for the training episode. This double dissociation shows that the limbic-diencephalic regions damaged in amnesia and the neostriatum damaged in Parkinson's disease support separate and parallel learning systems. In humans, the neostriatum (caudate nucleus and putamen) is essential for the gradual, incremental learning of associations that is characteristic of habit learning. The neostriatum is important not just for motor behavior and motor learning but also for acquiring nonmotor dispositions and tendencies that depend on new associations. 相似文献