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51.
In four Dutch communities, Zeist, De Bilt, Driebergen, and Doorn (total population, 111,000 inhabitants), all patients who suffered acute coronary events between July 1970 and March 1974 were recorded. By combining data from this study with data from the 1971 national census of the Netherlands, it was possible to demonstrate that the incidence of acute coronary events is twice as high for self-employed men as for employed men and as much as seven times as high for self-employed women as for housewives. The incidence of acute coronary events is practically the same for self-employed women aged 45-69 years as for men of the same age in the general population. Men aged 35-64 years whose nature is such that they feel driven to do all their work with great intensity and against the clock ("self-driven men") suffer myocardial infarction seven times as frequently as others and are 2.4 times as likely to die of fatal coronary attack. Only 10% of the self-employed male referents, but 50% of the self-employed male cases, consider themselves self-driven. On the other hand, experiences of excessive working hours and time pressures are not related to the incidence of acute coronary events. These results were not influenced by and were independent of other known risk indicators.  相似文献   
52.
To assess if a specific lesion pattern or changes of the basal limbic system as seen in primary depression and depression associated with neurodegenerative disorders might be identified in depressive multiple sclerosis (MS) patients, we submitted 78 MS patients to a MRI examination consisting of a quantitative measurement of lesions and of hyperintense signals from the pontomesencephalic midline (raphe). Furthermore relaxometry of the pontomesencephalic midline, a transcranial ultrasound examination rating its echogenicity semiquantitatively and a standardized neurological, neuropsychiatric and neuropsychological assessment were obtained. Thirty-one patients fulfilled the DSM-IV criteria for depression. Depressed MS patients had a significantly larger temporal lesion load than non-depressed MS patients, especially on the right side. A trend of difference was detected for lesions of the right parietal lobe, the right frontal lobe, the cerebellum and the total lesion load. Neither hyperintense signals or relaxometry nor echogenicity of the region at the level of the pontomesencephalic midline were significantly different between the groups. We conclude that depression in MS patients is not associated with an alteration of the basal limbic system at the brainstem as seen in Parkinson's disease or unipolar depression but with an increased lesion load of the projection areas of the basal limbic system.  相似文献   
53.
A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for brain tumours is based on data from 9 randomized trials and 1 meta-analysis. Moreover, data from 2 prospective studies, 3 retrospective studies and 4 other articles were used. In total, 19 scientific articles are included, involving 4 266 patients. The results were compared with those of a similar overview from 1996 including 11 252 patients. The conclusions reached can be summarized as follows: The conclusion from SBU 129/2 that curative treatment is not available for patients with high-grade malignant glioma (grade III and IV) is still valid.The survival benefit from postoperative radiotherapy compared to supportive care only or chemotherapy is about 3-4 months, as demonstrated in earlier randomized studies.

Quality of life is now currently estimated and considered to be of major importance when reporting the outcome of treatment for patients with brain tumours.

There is no scientific evidence that radiotherapy using hyper- and hypofractionation leads to longer survival for patients with high-grade malignant glioma than conventional radiotherapy. There is large documentation, but only one randomized study.There is some documentation to support the view that patients with grade IV glioma and poor prognosis can be treated with hypofractionation and with an outcome similar to that after conventional fractionation. A shorter treatment time should be convenient for the patient.Documentation of the benefit of a radiotherapy boost with brachytherapy is limited and no conclusion can be drawn.There is no scientific evidence that radiotherapy prolongs life for patients with low-grade glioma.There are some data supporting that radiotherapy can be used to treat symptoms in patients with low-grade glioma. As no controlled studies have been reported, no firm conclusion can be drawn.  相似文献   
54.
The role of exposure to ambient air pollution has been a topic of interest as a potential risk factor for respiratory symptoms and asthma. We expected that the prevalence rates would vary in Norway between the capital, Oslo, the mountainous area Hallingdal and the industrial area Odda. Surveys were conducted in school children, aged 6-16 years, in; Oslo (n=2577), Hallingdal (n=1177) and Odda (n=831). The parent-reported prevalence of wheeze in past year was almost similar in Oslo (13. 1 (95% CI 11. 7-14. 5)) and Upper Hallingdal (14. 2 (13. 1–15. 3)), but lower in Odda (9. 0 (7. 0–11. 0)). The findings for severe respiratory symptoms were almost equal. The age patters within each area differed. The risk of wheeze ever (p < 0.001) and wheeze in past year (p=0.04) decreased with increasing age in Odda, while there was an increase in the risk of exercise induced wheeze in Oslo (p=0.02) and Hallingdal (p < 0.001). The lifetime prevalence of asthma was lowest in Odda (5. 4 (3. 8–7. 0)) compared to Oslo (9. 4 (8. 2–10. 6)) and Hallingdal (8. 5 (6. 8–10. 2)). There was a positive association between physical activity and wheeze in past year. The results do not support the hypothesis that respiratory morbidity is more common in urban than rural areas, age and physical activity can influence the prevalence rates of respiratory symptoms in school children.  相似文献   
55.
Objective To measure the gain in quality of life due to hormone replacement therapy for women with mild and severe menopausal symptoms.
Design Prospective study where data on quality of life and willingness to pay were collected by interview.
Setting Department of Gynaecology at Sodertalje Hospital near Stockholm.
Participants One hundred and four women aged 45 to 65 years treated for menopausal symptoms for at least one month.
Methods Quality oflife was measured by the time tradeoff and rating scale methods. The willingness to pay for hormone replacement therapy was investigated using the contingent valuation method.
Main outcome measures The quality adjusted life year weight measured with the rating scale and time tradeoff methods, and willingness to pay.
Results The increase in the quality adjusted life year weight due to hormone replacement therapy for women with mild symptoms was 0.26 according to the rating scale method and 0.18 according to the time tradeoff method. For women with severe symptoms the quality adjusted life year weight increased by 0.50 according to the rating scale method and by 0.42 according to the time tradeoff method. The mean willingness to pay for hormone replacement therapy per month was 2300 Swedish krone for women with mild symptoms and 4800 Swedish krone for women with severe symptoms (£1 = 10.3 Swedish krone).
Conclusions Hormone replacement therapy leads to a major improvement in quality of life for women with menopausal symptoms. Both for women with mild and severe menopausal symptoms the willingness to pay for the treatment also greatly exceeds the costs, indicating that hormone replacement therapy is economically beneficial for women with menopausal symptoms.  相似文献   
56.
To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation.  相似文献   
57.
PURPOSE: To investigate DNA fragmentation as a function of linear energy transfer (LET) after exposure to accelerated ions in the LET range 40-225 keV/microm. MATERIALS AND METHODS: Fragmentation patterns of double-stranded DNA in the range 5 kilobasepairs (kbp) to 5.7 megabasepairs (Mbp) were analysed after irradiation of low-passage GM 5758 normal human fibroblast cells with 60Co-photons, helium ions at 40 keV/microm and high-LET nitrogen ions between 80 and 225 keV/microm. Two separate pulsed-field gel electrophoresis protocols were used, optimized for separation of 1-6 Mbp and 5 kbp to 1.5 Mbp fragments. RESULTS: An increased probability of formation of short and medium-sized DNA fragments was revealed following high-LET irradiation. The DNA double-strand break (dsb) induction yields were, respectively, 5.8 and 6.9-8.8 x 10(-9) dsb bp(-1) Gy(-1) for 60Co-photons and ions. The ion yields were some 80-110% higher than those calculated according to a conventional approach, disregarding the fragment distributions. For photons, the yield was 13% higher. The corresponding relative biological effectiveness (RBE) of dsb induction was in the range 1.2-1.5. CONCLUSIONS: A significant non-random contribution to the number of dsb after irradiation with high-LET was confirmed by detailed fragment analysis using pulsed-field gel electrophoresis. The LET had a strong influence on the initial DNA fragment distribution, and hence also on the induction yields measured. However, when the LET was increased to the highest values studied for nitrogen ions, the yield decreased slightly.  相似文献   
58.
59.
CYP2C9-dependent drug metabolism is subject to large interindividual variation. To some extent, this is explained by genetic polymorphism with expression of enzyme variants that differ in catalytic activity. The aim of this study was to characterize the variation in CYP2C9 phenotype in relation to genotype, with further analysis of the CYP2C9 gene in metabolic outliers. A study population of 126 healthy white subjects were recruited and genotyped for the variant alleles, CYP2C9*1-3. In CYP2C9 phenotyping with losartan, three subpopulations were distinguished that differed in the number of CYP2C9*3 alleles (0, 1, or 2). A three-fold higher metabolic ratio (MR; urinary losartan/carboxymetabolite) was found comparing CYP2C9*1/*3 (n = 20) to CYP2C9*1/*1 (n = 81), but there was considerable variation within each genotype. Subjects genotyped as CYP2C9*1/*1, but with an unexpectedly slow oxidation of losartan, were selected for DNA-sequencing analysis of the CYP2C9 gene. Interestingly, single nucleotide polymorphisms (SNPs) could not be identified either in the 5'-flanking region, the nine exons, or exon-intron boundaries. However, sequencing of the CYP2C9 gene was also carried out in patients genotyped as CYP2C9*1/*1 but with an exceptionally low steady-state clearance of S-warfarin. Here, five different SNPs were identified. In further analysis of the healthy volunteers, it became evident that women on oral contraceptives (OCs) had slower oxidation of losartan (MR of losartan: 1.7) than women without OCs (MR of losartan: 0.86). This novel finding was not explained by a different frequency of variant alleles. In summary, CYP2C9 genotype and oral contraceptives both contribute to a large interindividual variation in CYP2C9 activity.  相似文献   
60.
Evaluation of the high-temperature tensile properties of Ti-6Al-4V manufactured by electron beam melting (EBM) and subjected to a low-temperature hot isostatic pressing (HIP) treatment (800 °C) was performed in this study. The high-temperature tensile properties of as-built and standard HIP-treated (920 °C) materials were studied for comparison. Metallurgical characterization of the as-built, HIP-treated materials was carried out to understand the effect of temperature on the microstructure. As the HIP treatments were performed below the β-transus temperature (995 °C for Ti-6Al-4V), no significant difference was observed in β grain width between the as-built and HIP-treated samples. The standard HIP-treated material measured about 1.4×–1.7× wider α laths than those in the modified HIP (low-temperature HIP)-treated and as-built samples. The standard HIP-treated material showed about a 10–14% lower yield strength than other tested materials. At 350 °C, the yield strength decreased to about 65% compared to the room-temperature strength for all tested specimens. An increase in ductility was observed at 150 °C compared to that at room temperature, but the values decreased between 150 and 350 °C because of the activation of different slip systems.  相似文献   
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