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The media have been heavily implicated as sources of overconcern with body focus, attractiveness, and thinness, primarily for women. Attendant negative consequences are widely assumed. Yet there appears to be a recent media trend to concern with physical health and fitness, rather than just appearance. This trend has not been empirically assessed. Further, previous research has not adequately explored the possibility that there may be an assortment of physical ideals represented in the media, which may vary according to the different audiences being targeted. The current study assessed magazine article content, examining gender differences, time trends, and magazine audience type. Four types of article content were examined: health, fitness, beauty, and weight loss, in an attempt to capture the major aspects of body focus. The numbers of articles containing such content were tallied, over a 12-year period, in a sample of magazines oriented to three distinct audiences: traditional, high fashion, and modern. Huge gender differences were obtained, with female-targeted magazines not surprisingly outstripping male-targeted ones for all content categories assessed. There were also clear differences in content between magazine types. Time-trend analyses indicated a decrease in emphasis on weight loss in women's magazines over the period studied, and a statistical trend for an increase in weight loss focus in men's magazines. We conclude that apparent trends toward healthier habits are not just thinness goals revisited.  相似文献   
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Electron microscopic studies of the intersticial cells of the renal medullar layer and the count of lipid granules in them were conducted in two experimental states accompanied by a reduction of the circulating blood volume--72 hours of water-free diet and intravenous administration of Lazyx that possesses a potent natriuretic and diuretic effect. The concentration of renin and angiotensin was determined in the plasma of the same animals, using the radioimmunoassay technique, and the juxtaglomerular apparatus of the kidneys was examined. The study has demonstrated that the reduction of the circulating blood volume is accompanied, on the one hand, by a significant elevation of the plasma concentration of renin and angiotensin, and, on the other hand, by a reduction of the number of lipid granules in the intersticial cells that is interpreted by the authors as an index of an increased synthesis of renal prostaglandins. It has been concluded that a close functional interrelashionship exists between the two hormonal systems of the kidneys that regulate the water-electrolyte homeostasis, i.e. the renin-angiotensin system and the prostaglandins system.  相似文献   
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A simple mathematical model is presented to explain a recent new discovery of an unusual membrane adaptive response in Sarcina ventriculi. In this response, this organism synthesizes very long chain alpha, omega-dicarboxylic acids ranging from 28 to 36 carbon atoms in length. The distribution of chain lengths of the new fatty acid species is not consistent with de novo synthesis but suggests elaboration from the existing regular-chain fatty acids by a coupling process. Here, we demonstrate, using a mathematical model, that if the molecular weights and relative abundances of regular chain fatty acids are known, the molecular weights and relative abundances of the new, very long chain dicarboxylic fatty acid species can be predicted using a model based on the random, pairwise combination of regular chain species. This combination takes place across the bilayer leaflet to form transmembrane fatty acids. It is proposed that this coupling phenomenon is regulated by the motional dynamics of the membrane.  相似文献   
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A food recording electronic device to simplify the collection of dietary data is described. The need for a subject to maintain a quantitative account of food intake, and for a dietitian to subsequently code this record prior to computer analysis, are both eliminated using this approach. In combination with an electronic kitchen balance, the recorder, which is based upon a single-board computer (SBC) and special keyboard, enables the weight, food type and time of consumption of each food to be recorded automatically in response to simple key entry. The resident program, transparent to the user, allows data from surveys lasting up to three weeks to be stored for subsequent serial downloading to a host computer.  相似文献   
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