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11.
Results from measurements of the electrical resistivity of copper and aluminum conductors under the action of a plane shock wave, and also analysis of the relationship between the electrical resistivity and the hydrostatic pressure and of the theoretical temperature dependence of the electrical resistivity, has made it possible to elucidate the role of defect formation due to the plastic deformation of the metal and to determine its contribution to the increase in electrical resisitivity of the metal. It has been established that the concentration of defects depends on the pressure gradient in a plane shock wave.Institute of Dynamics of Geospheres, Russian Academy of Science, Moscow 117334. Translated from Fizika Goreniya i Vzryva, Vol. 31, No. 3, pp. 47–53, May–June, 1995. 相似文献
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AG Martov VIa Simonov BM Krendel'' SS Zenkov SA Moskalenko 《Canadian Metallurgical Quarterly》1993,38(3):16-19
Hyperferremia is shown to affect antioxidant system of the body, oxidation-reduction reactions in the cells seen as shifts in lymphocyte chemiluminescence. Dynamic changes in lymphocyte chemiluminescence reflect the level of hyperferremia. 相似文献
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AG Shankar S Ashley M Radford A Barrett D Wright CR Pinkerton 《Canadian Metallurgical Quarterly》1997,15(7):2622-2630
PURPOSE: Histology has been identified as an important prognostic factor in Hodgkin's disease (HD) in adults. Information regarding the impact of histology on outcome in childhood HD is scarce. This study determines the effect of histology on the overall survival (OS) or progression-free survival (PFS) in a national series of children treated in a standardized manner. PATIENTS AND METHODS: The results of treatment of 331 assessable patients, treated between January 1, 1982 and June 30, 1992, in the United Kingdom Children's Cancer Study Group (UKCCSG) Hodgkin's study I were reviewed to evaluate OS, PFS, and deaths according to stage and histology. Treatment was either involved-field radiation alone (stage IA) or chlorambucil, vinblastine, procarbazine, and prednisolone (ChlVPP) chemotherapy with or without mediastinal radiation. All were clinically staged at diagnosis. RESULTS: Nodular sclerosing (NS) HD was the most common histologic subtype (155 of 331 patients [47%]) and was uniformly distributed through all stages. Lymphocyte-depletion (LD) HD was extremely uncommon (< 1%). Mixed-cellularity (MC) HD had the highest relapse rate, but this was only significant (P < .05) in stage I patients who received local irradiation alone. There was no other statistically significant difference in OS and PFS between the various histologic subtypes. Multivariate analysis for PFS and OS confirmed that stage was the most important prognostic factor and that histology did not have an effect after stratification by stage. CONCLUSION: This study demonstrates that with effective multiagent chemotherapy, histologic subtype does not influence outcome. The high relapse rates in stage I MC subtype indicates that MC HD is biologically aggressive and systemic treatment with or without local irradiation may be indicated. The high relapse rate in stage IV patients appeared to be independent of histology. 相似文献
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Obesity is a major risk factor for cardiovascular disease. However, a direct link between these two states is difficult to establish, since obesity frequently occurs with other disease states such as diabetes, hypertension and atherosclerosis. Clinical studies have clearly shown that uncorrected obesity is associated with cardiac hypertrophy and compromised ventricular function. A number of rodent models of obesity have been studied in terms of cardiovascular adaptations. Cardiac function of the obese Zucker rat appears to be normal at a younger age. Only after several months is depression in cardiac function discernable. These animals are mildly hypertensive, but do not exhibit the characteristic increase in cardiac output associated with human obesity. A unique characteristic of JCR:LA-cp rat is that they develop atherosclerotic and myocardial lesions. Hearts from these animals will maintain normal function when perfused with physiological levels of calcium. At higher calcium concentrations, however, mechanical function becomes impaired. Dietary-induced obese rats exhibit many of the hemodynamic alterations associated with human obesity, but there is no evidence to-date that these animals will develop severe cardiac depression. Short-term weight reduction apparently has beneficial cardiovascular effects, but weight cycling may be harmful. Given the widespread occurrence of obesity, further studies are warranted to characterize the cardiac manifestations of this condition. 相似文献
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K. V. Goncharov 《Glass and Ceramics》2007,64(5-6):187-189
The redox conditions for glass making are investigated on a working glass-melting furnace using molding sand. Data obtained
from instrumental measurements of the ROP of the glass mass and reasons for destabilization of the technological process are
presented.
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Translated from Steklo i Keramika, No. 6, pp. 6–8, June, 2007. 相似文献
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