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141.
LJ Reagan 《Canadian Metallurgical Quarterly》1997,87(11):1779-1787
This paper, based on an analysis of cancer articles published in popular periodical literature since the early part of the century, argues that gender has played a key role in medical and popular understandings of cancer. Cancer education, the author finds, has taught women and men different things. Public health materials created with the intention of improving health through education actually send a multiplicity of messages, not all of them helpful. This essay suggests that public health messages targeted by sex are problematic, although perhaps necessary. The paper also contributes to scholarship concerned with the question of how people develop their ideas about risk of disease. 相似文献
142.
HC Kwaan M Levin S Sakurai O Kucuk MW Rooney LJ Lis JW Kauffman 《Canadian Metallurgical Quarterly》1997,26(6):1061-1068
Digital gangrene was observed in a patient who had angiographic findings of digital arterial occlusion. The patient's blood showed a marked red blood cell aggregation with rouleaux formation in long chains, which could not be dispersed at shear rates up to 200 sec-1. Studies of the patient's blood revealed the presence of an abnormal fibrinogen capable of aggregating normal red blood cells. This fibrinogen was found by Raman spectroscopy to have an increased alpha-helical content, whereas the beta-sheet content was decreased. Defibrinogenation therapy with ancrod resulted in a dramatic symptomatic relief. The disappearance of the abnormal fibrinogen 6 months later and an absence of a family history indicate that this dysfibrinogenemia was acquired. 相似文献
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147.
F Licastro M Chiricolo MC Morini I Capri LJ Davis R Conte R Mancini C Melotti R Parente R Serra 《Canadian Metallurgical Quarterly》1995,41(4):235-241
Apparently healthy elderly donors were screened according to a simple protocol that included clinical examination and the determination of hematological and biochemical values. This screening was performed to detect subclinical alterations which might interfere with immune responses and trace element status. The elderly were divided into two groups. The first group consisted of 22 (age 76 +/- 1 years) positively selected elderly (PSE), i.e. healthy subjects with no hematological and laboratory alterations, the second one comprised 13 (age 75 +/- 1 years) negatively selected elderly (NSE). Data were then compared with those obtained from 40 (age 35 +/- 2 years) healthy young controls. In both groups of elderly donors, plasma zinc levels were normal, while plasma copper concentrations were increased. Intracellular values of zinc and copper in mono- and polymorphonuclear cells from both groups of elderly were within reference limits. After in vitro activation, granulocyte chemiluminescence activity was impaired only in NSE. A decrement in the number of circulating CD3 lymphocytes and an increase in CD8d, CD57 cells were found in PSE, while NSE showed an increased number of CD3,DR cells and CD8d, CD57, CD8b,CD57 and CD16,CD56 positive cells. Our results indicate that only plasma copper levels were affected by age, whereas subclinical alterations in hematological or biochemical values appear to impair immune responses in the elderly. 相似文献
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149.
AB van 't Wout H Blaak LJ Ran M Brouwer C Kuiken H Schuitemaker 《Canadian Metallurgical Quarterly》1998,72(6):5099-5107
To investigate the temporal relationship between human immunodeficiency virus type 1 (HIV-1) replicative capacity and syncytium-inducing (SI) phenotype, biological and genetic characteristics of longitudinally obtained virus clones from two HIV-1-infected individuals who developed SI variants were studied. In one individual, the emergence of rapidly replicating SI and non-syncytium-inducing (NSI) variants was accompanied by a loss of the slowly replicating NSI variants. In the other subject, NSI variants were always slowly replicating, while the coexisting SI variants showed an increase in the rate of replication. Irrespective their replicative capacity, the NSI variants remained present throughout the infection in both individuals. Phylogenetic analysis of the V3 region showed early branching of the SI variants from the NSI tree. Successful SI conversion seemed a unique event since no SI variants were found among later-stage NSI variants. This was also confirmed by the increasing evolutionary distance between the two subpopulations. At any time point during the course of the infection, the variation within the coexisting SI and NSI populations did not exceed 2%, indicating continuous competition within each viral subpopulation. 相似文献
150.
DJ JANACKOVIC V JOKANOVIC LJ KOSTIC-GVOZDENOVIC S ZEC D USKOKOVIC 《Journal of Materials Science》1997,32(1):163-168
Cordierite powders containing very pure submicrometre spherical particles have been synthesized by the ultrasonic spray pyrolysis. Aqueous solutions of silicic acid, Al(NO3)3·9H2O and MgCl2·6H2O were used as precursors. Scanning electron micrographs have shown that particle surfaces were smooth and the mean particle diameter was 0.834 m. For the estimation of chemical and phase composition and phase transformation temperatures, differential thermal analysis, thermogravimetric analysis, X-ray diffraction, energy dispersive spectroscopy and infrared analysis have been applied. It was found that during spray pyrolysis, the condensation of silicic acid mostly occurred while aluminium and magnesium ion remained incorported between Si–O–Si chains. By subsequent heating to over 800°C, Si–O–M bonds (M=Al, Mg) were formed. The synthesis of cordierite occurred by the crystallization of -cordierite from the amorphous phase at 900°C followed by the phase transformation of - into -cordierite in the temperature range 1100–1200°C. 相似文献