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871.
Sander K. R. van Zon Ute Bültmann Carlos F. Mendes de Leon Sijmen A. Reijneveld 《PloS one》2015,10(12)
Background
The magnitude of socioeconomic health inequalities differs across age groups. It is less clear whether socioeconomic health inequalities differ across age groups by other factors that are known to affect the relation between socioeconomic position and health, like the indicator of socioeconomic position, the health outcome, gender, and as to whether socioeconomic health inequalities are measured in absolute or in relative terms. The aim is to investigate whether absolute and relative socioeconomic health inequalities differ across age groups by indicator of socioeconomic position, health outcome and gender.Methods
The study sample was derived from the baseline measurement of the LifeLines Cohort Study and consisted of 95,432 participants. Socioeconomic position was measured as educational level and household income. Physical and mental health were measured with the RAND-36. Age concerned eleven 5-years age groups. Absolute inequalities were examined by comparing means. Relative inequalities were examined by comparing Gini-coefficients. Analyses were performed for both health outcomes by both educational level and household income. Analyses were performed for all age groups, and stratified by gender.Results
Absolute and relative socioeconomic health inequalities differed across age groups by indicator of socioeconomic position, health outcome, and gender. Absolute inequalities were most pronounced for mental health by household income. They were larger in younger than older age groups. Relative inequalities were most pronounced for physical health by educational level. Gini-coefficients were largest in young age groups and smallest in older age groups.Conclusions
Absolute and relative socioeconomic health inequalities differed cross-sectionally across age groups by indicator of socioeconomic position, health outcome and gender. Researchers should critically consider the implications of choosing a specific age group, in addition to the indicator of socioeconomic position and health outcome, as findings on socioeconomic health inequalities may differ between them. 相似文献872.
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874.
Gert Andres 《Genetica》1949,24(1):387-534
Ohne ZusammenfassungMit 18 Tabellen und 45 Textabbildungen 相似文献
875.
Leon Bernstein 《American journal of botany》1963,50(4):360-370
Bernstein , Leon . (U. S. Salinity Lab., Riverside, Calif.) Osmotic adjustment of plants to saline media. II. Dynamic phase. Amer. Jour. Bot. 50(4): 360–370. Illus. 1963.—The time-course of osmotic adjustment in bean and pepper plants to increased salinity of the medium was determined by periodic sampling of plants following salt additions to the medium. Bean plants adjusted to increases of 1 atm OP within a day, the adjustment in roots occurring primarily at night following salt addition at 6 pm , whereas leaves and stems made most of their adjustment in the daytime. Pepper plants did not adjust completely to 1.5 atm NaCl additions in 48 hr, but OP increased by about the same amount in both species (0.5—1.0 atm per day). Diurnal fluctuations in OP of leaves and stems of both species and in roots of pepper were matched by parallel fluctuations in K concentrations. Added NaCl caused increased concentrations of K in leaves and stems which were more or less replaced by more slowly absorbed ions, Ca and Mg in bean leaves and Na in bean stems. Other salts produced comparable immediate effects on K level, but K was replaced more rapidly if the cation added was readily accumulated by the bean (Ca). In roots, Na uptake predominated if Na salts were added but K uptake was important on the CaCl2 treatment. The K effects suggest a passive distribution of K between the cell and the medium. 相似文献
876.
877.
Leon Tetreault 《CMAJ》1964,91(2):61-66
The subjective effects of dextroamphetamine, methylphenidate and placebo were evaluated in 16 medical students during the period just prior to their final oral examinations. The subjects served as their own controls. The order of administration of the three medications for each student was randomized, and a double-blind technique was used throughout. A questionnaire method was employed for the collection of results, which proved to be a useful and effective means. It demonstrated that dextroamphetamine, methylphenidate and placebo were statistically different from one another with regard to their effect on efficiency of studying, fatigue, duration of sleep and appetite. There were also significant differences in the number of side effects caused by the three medications. The stimulants, however, did not increase the number of study hours, nor was their use recommended by the students when preparing for important examinations. 相似文献
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