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AS Pavlov VS Datsenko MA Fadeeva OA Zamiatin EV Kizhaev 《Canadian Metallurgical Quarterly》1980,26(3):3-8
The authors present an analysis of the causes of radiation induced complications in 383 patients referred to the Chair of Clinical Radiology from different medical institutions of the country. It was found that under distant gamma therapy, to prevent the development of complications the value of TDF-factor should not exceed 105--110, for the associated radiotherapy--130--140, and that for close focal roentgenotherapy--130--150. In vast majority of patients (95.3%) the complications resulted from surpassing the normal tissue tolerance. To prevent radiation injuries it is suggested to take into consideration the TDF-factor values, while in planning radiotherapy to choose such schedules of irradiation, which preclude any surpassing of the tolerance of normal tissues and organs adjacent to the tumor. 相似文献
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A multiobjective optimization problem involves multiple objectives, often conflicting, to be met or optimized. A Pareto front provides a set of best solutions to determine the trade-offs between the various objectives. New evolutionary approaches demonstrated its ability to build well-delineated Pareto fronts in diverse multiobjective optimization problems, including multicriteria optimization in job shop scheduling with regular and nonregular objective functions. Good parameter settings and appropriate representations can enhance the behavior of an evolutionary algorithm. The present article shows a study of the influence of distinct parameter combinations as well as different chromosome representations. Details of implementation and results are discussed. 相似文献
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S. K. Varma Erica Corral Erika Esquivel Daniel Salas 《Metallurgical and Materials Transactions A》1999,30(9):2539-2545
A solutionizing heat treatment of 2014 aluminum alloy reinforced with 0.15 volume fraction of alumina particles (VFAP) results
in deformation-induced precipitation during rolling and tensile deformation, with 0.10 VFAP, at room temperature. The extent
of precipitation increases with increase in time and/or temperature of solutionizing. An attempt has been made to identify
the various types of precipitates in the samples deformed to a given strain and in fractured conditions. The work-hardening
curves and tensile properties of the composites have been shown to be dependent on the time and temperature combination of
the solutionizing process. 相似文献
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Based on the findings of 206 examinations, the authors advance their opinion of the role of X-ray computed tomography (XRCT) in the diagnosis of gastric cancer. The authors think that if their developed procedure for X-ray computed tomography based on the use of usual air as the only contrast agent by measuring it out in doses and administering into the gastric at CT scanning, which is called pneumoroentgenocomputered tomography (PRCT), is employed, it, preserving all the traditional, already known, advances of XRCT additionally yields highly valuable information on a direct damage to the gastric wall itself. The findings suggest that PRCT is especially effective in intramurally growing gastric cancers, the so-called squamous carcinomas, which are hardly differentiated for diagnosis and which are most common. Noteworthy is the fact that in seemingly unquestionable exophytic gastric cancer, detecting intramural tumorous infiltration adjacent to the exophyte, PRCT thus provides evidence that the exophyte revealed is the peculiar top of an iceberg, whose base shows a significant exophytic gastric carcinoma. 相似文献
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IA Kostanyan EV Navolotskaya RI Nurieva VP Zav'ialov VM Lipkin 《Canadian Metallurgical Quarterly》1997,23(10):805-808
A specific interaction of [3H]Glu with T lymphocytes from the blood of healthy donors (Kd = 0.236 microM) was revealed and described. It was found that unlabeled quisqualate, a structural analogue of L-glutamic acid, and unlabeled dipeptides Ala-Glu, Glu-Ala, and Glu-Glu competitively inhibit the specific binding of [3H]Glu to T lymphocytes (with Ki 0.19, 2.4, 3.4, and 1.2 microM, respectively). Binding experiments with conjugates of labeled and unlabeled glutamic acid with dextran showed that the receptors of [3H]Glu are localized on the outer surface of the plasma membrane of T lymphocytes. 相似文献
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The vigilance reaction is characterized by a large bradycardia, a pressor response, and inspiratory apnea in anesthetized rabbits and the inhibition of movement in conscious rabbits. This affective response pattern can be elicited by electrical stimulation of the dorsolateral hypothalamus (the hypothalamic vigilance area) or the ventrolateral periaqueductal gray (the periaqueductal gray vigilance area). The present study sought to advance our understanding of the functional relationship between the hypothalamic vigilance area (HVA) and the periaqueductal gray vigilance area (PVA) by measuring the effects of transverse transections of the caudal portion of the ventrolateral PAG (vlPAG) upon the cardiovascular responses elicited from the dorsolateral hypothalamus and the rostral vlPAG. Selective transverse transections of the caudal vlPAG significantly reduced the magnitudes of the bradycardia and pressor response elicited by stimulation of the PVA rostral to the transection site, but had minimal impact on the cardiovascular responses evoked by stimulation of the HVA. These findings suggest that the cardiovascular responses elicited by stimulation of the vlPAG are mediated by a neural pathway that is parallel, at least in part, to the one that subserves the response elicited from the HVA. The results also provide support for the view that the PAG is not an essential structure in the mediation of the autonomic components of affective behaviors involving behavioral inhibition. 相似文献
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