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51.
Age-standardised mortality rates are often used in epidemiologic studies to describe the dimension of social inequalities in mortality. This, however, conceals any age-dependence of social inequality. In an ecologic study, all causes and cause-specific mortality of all citizens of Bochum, FRG, who died 1988-1990, were evaluated using 13.171 death certificates. Data was aggregated on census tract level. The social status of a census tract was determined using 6 variables from the census 1987 describing the socio-economic situation in each census tract. Census tracts were grouped into quintiles according to their social status. Age and sex-specific mortality rates as well as rate ratios, using the quintile with the highest social status as reference, were calculated. Results for men (n = 6.288) indicate that social inequality is age-dependent for total mortality. Social differentials are especially marked for the age groups 35-64 years. For age group < 35 years and > 84 years no social differentiation in mortality is visible. Similar patterns are found with mortality from cardiovascular diseases (ICD-9: 390-459) and cancer (ICD-9: 140-208). Mortality from diseases related to health behaviour such as lung cancer or diseases associated with high alcohol intake are characterised by social inequalities above average in the middle age groups. For total mortality in women (n = 6.883) large social differentials are found for age groups 25-34 years and 45-54 years. Efforts to reduce social inequality on community level should especially be aimed at adolescents and young adults living in underprivileged areas. 相似文献
52.
Association between intestinal vitamin D receptor, calcium absorption, and serum 1,25 dihydroxyvitamin D in normal young and elderly women 总被引:1,自引:0,他引:1
HK Kinyamu JC Gallagher JM Prahl HF DeLuca KM Petranick SJ Lanspa 《Canadian Metallurgical Quarterly》1997,12(6):922-928
This paper systematically reviews the results from epidemiologic studies investigating the hypothesis that breast cancer risk in postmenopausal women increases with increasing concentrations of estradiol in blood and with increasing urinary estrogen excretion rates. Data from 29 epidemiologic studies of endogenous hormones and postmenopausal breast cancer were used. The ratio of the average estrogen concentration in the women with breast cancer to that in the women without breast cancer (and its 95 percent confidence interval [CI]) was calculated for each study, and the results were summarized by calculating weighted averages of the log ratios. In six prospective studies of serum estradiol concentration, 329 women who subsequently developed breast cancer had, overall, a 15 percent (CI = 6-24 percent, P = 0.0003) higher mean concentration of estradiol in their blood than the 1,105 women who remained free of cancer. The results of these prospective studies did not differ significantly from each other (chi2 for heterogeneity = 8.7; degrees of freedom = 5; P > 0.1). Similar differences in mean estrogen levels were seen in the case-control studies which reported either estradiol concentrations in the blood or urinary estrogen excretion. However, the case-control studies showed significant heterogeneity among their results. The data from the prospective studies strongly suggest that breast cancer risk in postmenopausal women is associated with relatively high concentrations of endogenous estradiol. 相似文献
53.
S. H. Cheong S. H. Ro J. Y. Shon A. M. Al-Jumaily 《Journal of Mechanical Science and Technology》2008,22(8):1499-1503
To understand how the input impedance determined at the throat correlates with changes in the dynamic characteristics of the
airways, a simplified 5-lobe model is developed and simulated. The model takes into account some realistic conditions such
as varying cross-sectional areas, flexible wall properties and branching. The lobe terminal impedances are implemented in
the model to predict the input impedance at the throat. The effects of airway constrictions and wall elastance variations
on this impedance are determined for a range of frequencies. It is concluded that the developed model is capable of predicting
various physiological changes in the airway passages. 相似文献
54.
55.
Seungho Kim Woon Jin Chung Somi Jung Gyuin Shim Huiyeon Shon Seung Kim Kyeong Dae Park 《Journal of the American Ceramic Society》2023,106(1):569-581
The fracture mechanism of a chemically strengthened ultrathin glass (UTG) for the cover window of flexible display devices was investigated under pen loading conditions for the first time to better understand the UTG impact resistance characteristics. High-speed camera analysis, fracture fragment analysis, and finite element modeling were employed to investigate the fracture mechanism of the UTG under pen drop conditions. A pen-on-plate (POP) test was also employed to examine the fracture characteristics under static loading condition, and its results were compared with those of the pen drop test (PDT) to find a correlation between the static and dynamic loading conditions. The correlation found between the POP and PDT tests indicates that a quantitative estimation of contact displacement under PDT can be obtained by measuring the first ring crack size, to more easily determine the impact resistance characteristics of UTG. 相似文献
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57.
Jinhan Shon Young Yun Malshick Shin Koo Bok Chin Jong‐Bang Eun 《Journal of the science of food and agriculture》2009,89(8):1407-1415
BACKGROUND: Mixtures of milk proteins and gums incorporated into bread formulations may enhance the quality of bread and retard the deterioration of frozen dough. Our objective was to investigate the effects of mixtures of milk proteins (casein (C) and whey protein (W)) and gums (sodium alginate (A) and κ‐carrageenan (K) on the quality of bread made from frozen dough. We hypothesized that bread containing milk proteins and gums would be of improved quality. Milk proteins improve texture, moisture retention and specific volume, and reduce the size of ice crystals, while gums incorporated into the bread improve moisture retention, control water mobility and prevent the growth of ice crystals, so we hypothesized milk proteins and gums would suppress the quality deterioration of bread during frozen storage. RESULTS: We found that mixtures of milk proteins and gums proved effective with regard to the maintenance of the baking quality of frozen dough. Breads containing CA had a higher specific loaf volume than the control bread. The addition of WK enhanced crumb firmness during extended frozen storage. In sensory evaluation, the addition of WA and CA contributed to the improvement of baking quality, taste, texture and acceptability. CONCLUSION: These findings are consistent with the hypothesis that mixtures of milk proteins and gums improved baking quality by reducing the deterioration of frozen dough. These results indicate that the addition of CA and WA improved the bread quality and WK could effectively be used as an anti‐staling agent in bread. Copyright © 2009 Society of Chemical Industry 相似文献
58.
Oligodendrogliomas are uncommon intracranial glial tumours in which extracranial spread is only rarely reported. Similarly, both intracranial and ocular medulloepitheliomas are also rare, with metastatic spread from the ocular neoplasm being less common than its intracranial counterpart. We report cases of an intracranial oligodendroglioma and an ocular medulloepithelioma both of which metastasised to the parotid gland. To our knowledge these are only the second oligodendroglioma and the third ocular medulloepithelioma to be reported as metastasising to this site. 相似文献
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