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911.
Urban air pollution and mortality in a cohort of Norwegian men   总被引:11,自引:0,他引:11  
We investigated the association between total and cause-specific mortality and individual measures of long-term air pollution exposure in a cohort of Norwegian men followed from 1972-1973 through 1998. Data from a follow-up study on cardiovascular risk factors among 16,209 men 40-49 years of age living in Oslo, Norway, in 1972-1973 were linked with data from the Norwegian Death Register and with estimates of average yearly air pollution levels at the participants' home addresses from 1974 to 1998. Cox proportional-hazards regression was used to estimate associations between exposure and total and cause-specific mortality. During the follow-up time 4,227 men died from a disease corresponding to an ICD-9 (International Classification of Diseases, Revision 9) code < 800. Controlling for a number of potential confounders, the adjusted risk ratio for dying was 1.08 [95% confidence interval (CI), 1.06-1.11] for a 10- microg/m3 increase in average exposure to nitrogen oxides (NOx) at the home address from 1974 through 1978. Corresponding adjusted risk ratios for dying from a respiratory disease other than lung cancer were 1.16 (95% CI, 1.06-1.26); from lung cancer, 1.11 (95% CI, 1.03-1.19); from ischemic heart diseases, 1.08 (95% CI, 1.03-1.12); and from cerebrovascular diseases, 1.04 (95% CI, 0.94-1.15). The findings indicate that urban air pollution may increase the risk of dying. The effect seemed to be strongest for deaths from respiratory diseases other than lung cancer.  相似文献   
912.
Secoisolariciresinol diglucoside (SDG) is an important dietary lignan that is found at very high levels in flaxseed (1-4 %, w/w). Flaxseed lignans have received much research interest in recent years because of reported phyto-oestrogenic, anticarcinogenic, and anti-atherogenic effects. Previously, flaxseed feeding has been shown to decrease vitamin E concentrations in rats despite the antioxidant potential of SDG in vitro. Sesamin, a sesame lignan, on the other hand has been shown to increase vitamin E concentrations in rats. The aim of the present study was to investigate the effect of dietary SDG and its oligomers on vitamin E and cholesterol concentrations in rats. SDG was extracted from defatted flaxseed flour with a dioxane-ethanol mixture and purified by silica column chromatography. The major oligomers with 3-hydroxy-3-methyl glutaric acid, containing a high ratio of SDG to p-coumaric and ferulic acid glucosides, were purified from the extracts by reversed-phase liquid chromatography. When fed to rats at 0.1 % in the diet for 27 d, both SDG and its oligomers had no effect on animal performance but caused an increase in liver cholesterol and a 2-fold reduction in the levels of alpha- and gamma-tocopherols in rat plasma and liver. It is notable that a phenolic antioxidant, such as SDG, causes a vitamin E-lowering effect in rats. This cannot be explained at present, but warrants further investigations with respect to the magnitude, mechanism, and significance of the observed effect for human nutrition.  相似文献   
913.
OBJECTIVE: To estimate the effects of smoking on quality of life over time, using the Years of Healthy Life (YHL) construct. DATA SOURCES/STUDY SETTING: The Health and Retirement Study (HRS) survey (N=12,652) of persons 50 to 60 years old and the Asset and Health Dynamics Among the Oldest Old (AHEAD) survey (N=8,124) of persons > or =70 years old, plus spouses regardless of age, followed from 1992/1993 to 2000. STUDY DESIGN: Years of healthy life from baseline to death were estimated. Regression models were developed with smoking as the main explanatory variable and with both YHL and years of life remaining as the outcome variables. PRINCIPAL FINDINGS: Smoking was strongly and consistently related to YHL lost. In HRS, individuals who had quit smoking at least 15 years prior to baseline had a similar number of YHL left as never smokers. CONCLUSIONS: Efforts to encourage smoking cessation should emphasize the impact of these factors on quality of life.  相似文献   
914.
Iron status during infancy and early childhood reflects highly dynamic processes, which are affected by both internal and external factors. The regulation of iron metabolism seems to be subjected to developmental changes during infancy, although the exact nature of these changes and their implications are not fully understood. We wanted to explore the association between dietary iron intake and indicators of iron status, and to assess temporal changes in these variables. This was done by secondary analysis of data from a recently conducted dietary intervention trial in which healthy, term, well-nourished infants were randomly assigned to consume iron-fortified infant cereals with regular or low phytate content, or iron-fortified infant formula. Dietary iron intake from 6 to 8 mo and from 9 to 11 mo was associated with hemoglobin (Hb) concentration at 9 mo (r = 0.27, P < 0.001) and 12 mo (r = 0.21, P = 0.001), respectively, but iron intake from 12 to 18 mo was not associated with Hb at 18 mo. In contrast, iron intake from 6 to 11 mo was not associated with serum ferritin (S-Ft) at 9 or 12 mo, whereas iron intake from 12 to 17 mo was positively associated with S-Ft at 18 mo (r = 0.14, P = 0.032). These shifts in associations between dietary iron intake, and Hb and S-Ft, respectively, may be due to developmental changes in the channeling of dietary iron to erythropoiesis relative to storage, in the absence of iron deficiency anemia. These observations should be taken into consideration when evaluating iron nutritional status during infancy and early childhood.  相似文献   
915.
Alkylresorcinols (AR) are a class of amphiphilic phenolic lipids present in high amounts in wheat and rye bran. They have been reported to be both growth retarding and innocuous when fed to rats, and to have a broad range of bioactivities in vitro, suggested to be related to their ability to bind to proteins and modify membranes. This study was designed to test the effects of AR (purified from rye bran) on growth, tocopherol levels, and cholesterol levels in rats. Rats were fed 1 of 4 different levels of AR for 4 wk: 0 (control), 1, 2, and 4 g/kg diet. AR did not affect final body, liver, or lung weights. The AR diets increased the levels of gamma-tocopherol in liver and lungs (P < 0.05). To investigate whether AR could have increased gamma-tocopherol levels via inhibition of tocopherol-omega-hydroxylase, HepG2 cells were incubated with AR and the metabolism of gamma-tocopherol measured. AR significantly inhibited the conversion of gamma-tocopherol to its water-soluble hydroxychroman metabolite in vitro, indicating that AR may increase gamma-tocopherol levels via inhibition of tocopherol metabolism in vivo. The 4 g AR/kg diet decreased liver cholesterol (P < 0.001), but did not affect plasma lipids. AR were detected in the perirenal adipose tissue samples of rats fed AR, indicating that they can accumulate in the fatty tissues of rats. High levels of dietary AR moderately affect gamma-tocopherol, possibly via inhibition of tocopherol metabolism, and decrease liver cholesterol in rats.  相似文献   
916.
In a laboratory experiment we documented effects of sublethal concentrations of p,p'-2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE) and butylbenzylphthalate (BBP) on feeding behavior in threespine stickleback Gasterosteus aculeatus. The fish were exposed for 31 days to either BBP (10 or 100 microg/L) or DDE (5 or 50 microg/L) or to a mixture of BBP and DDE in the corresponding concentrations. Five weeks after exposure termination, we showed that fish that had been exposed to the higher concentrations of DDE and/or BBP initiated feeding more often than control fish. The latency time to feeding (ranging from 0.25 to 5.0 min) differed between control fish and fish exposed to mixtures of DDE and BBP. This experiment shows that feeding behavior may be used as a suitable behavioral variable in the detection of effects of pollutants even long time after the termination of exposure.  相似文献   
917.
OBJECTIVE: To examine whether increasing cumulative deprivation has an incremental effect on total as well as cause specific mortality. DESIGN: Census data on housing conditions as indicators of deprivation from 1960, 1970, and 1980 were linked to 1990-98 death registrations. Relative indices of inequalities were computed for housing conditions to measure the cumulative impact of differences in social conditions. PARTICIPANTS: 97 381 (71.1%) 30-49 year old and 70701 (80.0%) 50-69 year old inhabitants of Oslo, Norway, in 1990 with census information on housing conditions and recorded length of education. MAIN RESULTS: Mortality risk was increased when all censuses' housing conditions were summed in both age groups and sex. The cause specific analysis indicated such an effect particularly for coronary heart disease, chronic obstructive lung disease, and smoking related cancers. Violent deaths were essentially associated with housing conditions closer to the time of death in men in both age groups and in young women. CONCLUSIONS: To fully account for socially mediated risk of death, a full life course approach should be adopted. The relative importance of each stage seems to vary by cause of death.  相似文献   
918.
PURPOSE: To study the refraction achieved after same-day bilateral cataract surgery, particularly with regard to anisometropia and the incidence of patient dissatisfaction caused by this complication. SETTING: Department of Ophthalmology, University Hospital of Link?ping, Sweden. METHODS: This was a retrospective study of 165 consecutive patients who had bilateral cataract surgery on the same day. Parameters examined were preoperative and postoperative visual acuity and refraction (spherical equivalent), preoperative keratometry and axial lengths, planned postoperative refraction, difference between planned and achieved refraction, anisometropia, and recorded evidence of patient dissatisfaction resulting from refraction or binocularity problems. RESULTS: Postoperative refraction was within +/-0.5 diopter (D) from target in 43%, +/-1 D from target in 71%, and +/-2 D from target in 95% of eyes. Anisometropia was < or =0.5 D in 48% of patients and < or =1 D in 82% of patients. Two patients (1.2%) had anisometropia >2 D. No patient returned with complaints caused by postoperative refraction. CONCLUSIONS: Although deviation from planned postoperative refraction occurred in several cases, no patient reported binocularity problems in the 1% of cases with significant anisometropia. Risk for deviation from planned refraction does not appear to be a contraindication to same-day bilateral phacoemulsification in patients without known risk factors.  相似文献   
919.
920.
Since the identification of the dopamine D(4) receptor subtype and speculations about its possible involvement in schizophrenia, much work has been put into development of selective D(4) ligands. These selective ligands may be effective antipsychotics without extrapyramidal side effects. This work describes the synthesis of a new series of 2,4-disubstituted morpholines and 2,4-disubstituted 1,4-oxazepanes with selectivity for the dopamine D(4) receptor. A 3D-QSAR analysis using the GRID/GOLPE methodology was performed with the purpose to get a better understanding of the relationship between chemical structure and biological activity. Inspection of the coefficient plots allowed us to identify that regions which are important for affinity are situated around the two benzene ring systems, a p-chlorobenzyl group, and the aliphatic amine belonging to the morpholine or 1,4-oxazepane system. In addition, the size of the morpholine or 1,4-oxazepane ring seems to be important for affinity.  相似文献   
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