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151.
Esteve Fernandez Carlo La Vecchia Barbara D'Avanzo Claudia Braga Eva Negri Silvia Franceschi 《European journal of epidemiology》1997,13(3):267-273
To describe the relationship between sociodemographic factors, life-style habits, selected dietary indicators, smoking-related variables, and quitting smoking we analyzed data derived from the comparison group of a case-control study of colorectal and breast cancers based on a network of teaching and general hospitals in Northern Italy. A total of 2621 subjects (1215 women and 1406 men) who were ever cigarette smokers were included for analysis. Age-adjusted rates of stopping smoking (quit rates) and multivariate odds ratios (OR) of quitting smoking were computed. The overall age-adjusted quit rate was 38.6% for males and 24.9% for females, corresponding to an OR of quitting of 0.6 (95% CI: 0.5–0.7) for females vs males. The quitting rate increased with increasing age. After allowing for age, smoking cessation was more frequently reported by more educated or higher social class individuals. No relationship was present between quitting smoking and alcohol consumption, but quitting smoking was inversely related to coffee consumption. The probability of quitting smoking increased directly with number of cigarettes among males but not among females, who showed a J-shaped pattern. Older, heavy smokers were more likely to give up smoking. A general pattern of increasing rates of quitting smoking with higher consumption of vegetables and fruit, and hence -carotene, was present. This study confirms a positive association between quitting smoking and increasing age, higher education, low coffee consumption, heaviness of smoking and high consumption of vegetables and fruit. 相似文献
152.
S. Alonso A. Castro I. Fernandez M. Gömez de Cedrön A. Garcia-Orad E. Meyer M. Martínez de Pancorbo 《International journal of legal medicine》1995,107(5):239-245
The tetrameric STRs, HUMTH01, HUMVWA31A and HUMFES/FPS, were studied in a population from the Basque Country (northern Spain) for their frequency distribution and applicability to identity and paternity testing. All systems conformed to Hardy-Weinberg equilibrium; pairwise comparisons demonstrated the allelic independence between loci, and furthermore, all systems seemed to be in agreement with expectations from the Stepwise Mutation Model (SMM) of the mutation-drift theory, which indicates the homogeneity of the population and suggests a replication slippage mechanism as a possible model for generating alleles. A comparison with other population groups appeared to indicate that frequencies are well conserved in Caucasians, but differ from other racial groups. The calculated parameters a priori probability of exclusion (PEX) and index of discrimination (ID), show the informativeness of these loci for the determination of identity and relatedness of individuals. 相似文献
153.
A. Vallcanera Calatayud C. Sangüsa Nebot M. Martinez Fernandez H. Cortina Orts 《Pediatric radiology》1994,24(1):74-75
Severe unilateral varus deformity of the distal end of the femur secondary to a focal fibrous lesion is reported. It is a malformative process rare at this level, this being the first report of it in the radiological literature. The conventional radiograph is pathognomonic and CT is useful in the confirmation of the fibrous tissue. Osteotomy is indicated only if the deformity progresses or the angle of varus is severe. 相似文献
154.
Fernandez E Schiaffino A La Vecchia C Borrás JM Nebot M Saltó E Tresserras R Rajmil L Villalbí JR Segura A 《Preventive medicine》1999,28(4):361-366
BACKGROUND: Few studies have investigated the association between age at starting smoking and the average number of cigarettes smoked per day in adulthood. To provide further evidence on this issue, we analyzed data from the Catalan Health Interview Survey (CHIS). METHODS: The CHIS was conducted in 1994 on a randomly selected sample (N = 15,000) of the population of Catalonia, Spain. A total of 4,897 current or exsmokers (3,276 males and 1,621 females) were included for analysis. Age-standardized proportions of subjects smoking <15, 15-24, and >/=25 cigarettes/day, age-standardized mean number of cigarettes smoked per day, and multivariate odds ratios (OR) of being a heavy smoker (>/=25 cigarettes/day) according to age at starting smoking (<15, 15-17, 18-19, >/=20 years) were computed. RESULTS: Men who started smoking before the age of 15 smoked on average 5.5 cigarettes more than those who started at age 19 or over. Women who started smoking early in life smoked, on average, 6.8 cigarettes/day more than women who started later. The proportion of smokers of <15 cigarettes/day was higher among subjects who started smoking later. Both for males and for females, the OR of being a heavy smoker significantly increased with decreasing age at starting smoking (OR = 2.4 for males and 4.5 for females who started at age <15 versus >/=20 years). The level of education did not modify the relationship in males, whereas the association with age at starting was only apparent for more educated women. CONCLUSIONS: This study confirms that age at starting smoking is inversely and strongly associated to the number of cigarettes smoked per day. Thus, actions aimed at the prevention or delay of smoking onset among adolescents would have an important beneficial effect. 相似文献
155.
Venarucci D Venarucci V Vallese A Battilà L Casado A De la Torre R Lopez Fernandez ME 《Panminerva medica》1999,41(4):335-339
Free radical are highly reactive chemical species with an unpaired electron in an atomic or molecular orbital. In biological systems, the most important free radicals are superoxide anion and hydrogen peroxide; in the presence of transition metals such as iron, copper and manganese both these free radicals produce hydroxyl radicals. Free radicals attack proteins, nuclei acids and membranes containing large quantities of polyunsaturated fatty acids. Because of their toxicity, the organism has developed ways to deactivate them. The superoxide dismutase enzyme (SOD) catalyzes dismutation of the superoxide radical into hydrogen peroxide and oxygen hydrogen peroxide is in turn reduced to water and oxygen by peroxidase glutathione and catalase enzymes. The production of radicals in the brain is due to catecholamine metabolism such as dopamine and norepinephrine and is increased by the presence of transition metals and by a deficiency of antioxidant agents such as vitamin E. Two main groups of dementia exist in older age: the multi-infarctual dementias, caused by cerebrovascular disorders and the primary degenerative disorders such as Alzheimer, where no vascular disease is evident. Free radicals play an important role in Parkinson's disease, in Alzheimer's disease and in stroke. The value of SOD and CAT activity following the above mentioned degenerative diseases differ among the various studies carried out. In Alzheimer's disease, the value of SOD activity probably increases in the neuropathologically involved areas. In stroke, the SOD value does not vary either in the ischemic area or in the peri-infarctual one during the first 24 hrs after lesion, while the CAT value decreases. 相似文献
156.
Vidal-Quintanar RL Mendívil RL Peña M Fernandez ML 《The British journal of nutrition》1999,81(4):281-288
Lime-treated maize husks (LTCH), a by-product of tortilla manufacturing in Mexico, have been shown to decrease plasma LDL-cholesterol levels in guinea-pigs by specific alterations in hepatic cholesterol metabolism. To determine whether LTCH would also lower plasma cholesterol levels in normal and hyperlipidaemic individuals, the fibre content of a typical diet was increased by supplementing free-living subjects in North-West Mexico with cookies containing 450 g LTCH/kg. Normal subjects (n 11) with plasma cholesterol levels of less than 5.7 mmol/l and hypercholesterolaemic subjects (n 12) with plasma cholesterol levels higher than 5.7 mmol/l participated in the study. Plasma glucose, cholesterol, triacylglycerol, LDL-cholesterol and HDL-cholesterol concentrations, LDL:HDL values and blood pressure were determined at baseline and after 6 weeks of supplementation with LTCH. LTCH supplementation significantly lowered the plasma total cholesterol level by 11-15% and LDL-cholesterol by 25%, and improved the LDL:HDL value by 29-33% (P < 0.01) in both normal and hypercholesterolaemic subjects. HDL-cholesterol, triacylglycerol and glucose concentrations did not change. Both groups consumed equal amounts of LTCH per week; individuals showed excellent compliance and good acceptance of the product. Neither group changed their dietary habits during the time of the experiment as determined by 3 d dietary records at baseline and at week 6. We conclude that LTCH supplements are suitable to increase fibre intake and reduce plasma LDL-cholesterol levels in healthy and hypercholesterolaemic subjects in this population. 相似文献
157.
158.
E. Fernandez A. Schiaffino L. Rajmil X. Badia A. Segura 《Journal of epidemiology and community health》1999,53(4):218-222
BACKGROUND AND OBJECTIVES: While socio-economically derived differences in health and health services use have long been a subject of study, differences based on gender, considered as the explicative variable, have scarcely been quantified from population-based data. The aim of this investigation was to analyse inequalities in health and health care services utilisation between men and women in Catalonia (Spain). DESIGN, SETTING, PARTICIPANTS, AND MEASURES: Data from the Catalan Health Interview Survey, a cross sectional survey conducted in 1994, were used. A total of 6604 women and 5641 men aged 15 years or over were included for analysis. Health related variables studied were self perceived health, restriction of activity (past two weeks), and presence of chronic conditions; health services use variables analysed were having visited a health professional (past two weeks), an optometrist (12 months), or a dentist (12 months); and hospitalisation (past 12 months). Age standardised proportions were computed according to gender, and prevalence odds ratios (OR) were derived from logistic regression equations. MAIN RESULTS: Women more frequently rated their health as fair or poor than men (29.8% v 21.4%; OR = 1.22; 95% CI: 1.10, 1.34). More women than men reported having restricted activity days (OR = 1.86; 95% CI: 1.59, 2.18) and chronic conditions (OR = 1.74; 95% CI: 1.60, 1.89). The proportion of women visiting a health professional was slightly greater than that for men (OR = 1.20; 95% CI: 1.09, 1.31), as was the proportion of women visiting an optometrist (OR = 1.21; 95% CI: 1.11, 1.33), and a dentist (OR = 1.43; 95% CI: 1.31, 1.55). The proportion of hospitalisation was lower in women (6.6%) than in men (7.7%; OR = 0.73; 95% CI: 0.63, 0.85). When health services use was analysed according to self perceived health, women declaring good health reported a greater probability of consulting a health professional (OR = 1.35; 95% CI: 1.20, 1.52). There were no differences in respect to hospitalisation, visits to the optometrist and to the dentist. CONCLUSIONS: These results indicate a pattern close to the inverse care law, as women, who express a lower level of health and thus would need more health care, are not, however, using health services more frequently than men. 相似文献
159.
Triantafilou K Triantafilou M Wilson KM Cherry RJ Fernandez N 《Human immunology》1999,60(11):1101-1112
The intracellular and cell-surface heterotypic associations of HLA-DR in the presence and absence of the invariant chain were investigated. Simultaneous confocal microscopy imaging of the Golgi apparatus and HLA-DR molecules revealed that cells transfected only with HLA-DR and not the invariant chain or HLA-DM, accumulate class II molecules mostly in the Golgi apparatus, proximal to the cell nucleus. In contrast, in cells transfected with both HLA-DR and the invariant chain, or HLA-DR, the invariant chain and HLA-DM, the class II molecules are more evenly distributed in intracellular compartments. Confocal microscopy and flow cytometry revealed that in the absence of the invariant chain, a greater number of HLA-DR molecules are transported to the cell surface. Biochemical experiments and nonequilibrium pH gradient electrophoresis revealed that HLA-DR associates with surface invariant chain in the presence of HLA-DM. In cells that lack HLA-DM, no cell-surface association of HLA-DR and Ii was observed. Taken together, these results reveal two separate and distinct functions for surface and intracellular invariant chain subsets. The intracellular invariant chain "arrests" the class II molecules in the endocytic pathway. In contrast, cell-surface invariant chain associates with class II molecules at the cell surface, possibly playing a role in recycling empty class II molecules or as an accessory molecule. 相似文献
160.