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61.
B E Woodcock E Smith W H Lambert W M Jones J H Galloway M Greaves F E Preston 《BMJ (Clinical research ed.)》1984,288(6417):592-594
Reports suggest that the low incidence of ischaemic heart disease in Greenlandic Eskimos is related to the effect of a diet rich in eicosapentaenoic acid on platelet reactivity and plasma lipid concentrations. A double blind randomised investigation was therefore conducted of the effects on blood viscosity of dietary supplementation with an oil rich in this fatty acid (1.8 g/day, given as fish oil) and an eicosapentaenoic acid poor oil (as corn/olive oil) in patients with peripheral arterial disease. A statistically significant reduction in whole blood viscosity was observed at seven weeks in those patients receiving the eicosapentaenoic acid rich oil. No changes in plasma viscosity, haemoglobin concentration, packed cell volume, or platelet count were seen. A significant fall in plasma triglyceride concentration was also noted only in the patients receiving oil rich in eicosapentaenoic acid; plasma concentrations of cholesterol and high density lipoprotein cholesterol were unchanged. It is concluded that rheological changes that result from a diet rich in eicosapentaenoic acid may contribute to the suggested protective effects of such a diet against arterial disease and that such changes are of potential therapeutic importance in established arterial disease. 相似文献
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The ageing mitochondrial genome 总被引:2,自引:0,他引:2
The population of elderly individuals has increased significantly over the past century and is predicted to rise even more rapidly in the future. Ageing is a major risk factor for many diseases such as neurodegenerative disease, diabetes and cancer. This highlights the importance of understanding the mechanisms involved in the ageing process. One plausible mechanism for ageing is accumulation of mutations in the mitochondrial genome. In this review, we discuss some of the most convincing data surrounding age-related mtDNA mutations and the evidence that these mutations contribute to the ageing process. 相似文献
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P. M. Webb T. Knight S. Greaves A. Wilson D. G. Newell J. Elder D. Forman 《BMJ (Clinical research ed.)》1994,308(6931):750-753
OBJECTIVES--To relate the prevalence of infection with Helicobacter pylori in adults to their living conditions in childhood to identify risk factors for infection. DESIGN--Prevalence study of IgG antibodies to H pylori (> 10 micrograms IgG/ml, determined by enzyme linked immunosorbent assay (ELISA)) and reported living conditions and other socioeconomic factors in childhood. SETTING--Three factories in Stoke on Trent. SUBJECTS--471 male volunteers aged 18 to 65 years. MAIN OUTCOME MEASURES--Seroprevalence and variables in childhood. RESULTS--Seroprevalence of H pylori increased with age (22/74 (29.7%) at < 30 years v 29/46 (63%) at 55-65 years; P < 0.001 for trend) and was related to manual occupation (14/65 (21.5%) for non-manual v 162/406 (39.9%) for manual; P = 0.003). After data were adjusted for age and occupation subjects from large families, whose childhood homes were crowded or who regularly shared a bed in childhood, were significantly more likely to be seropositive (adjusted odds ratio (95% confidence interval) 2.15 (1.41 to 3.30) for crowding and 2.13 (1.38 to 3.30) for sharing a bed), but there was no relation with possession of a bathroom, inside toilet, refrigerator, or household pets in childhood. CONCLUSIONS--Close person to person contact in childhood is an important determinant of seroprevalence of H pylori in adulthood, suggesting that the infection is transmitted directly from one person to another and may be commonly acquired in early life. 相似文献
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A screen for identifying genes interacting with armadillo, the Drosophila homolog of beta-catenin 总被引:29,自引:0,他引:29
Applications of quantitative genetics and conservation genetics often require measures of pairwise relationships between individuals, which, in the absence of known pedigree structure, can be estimated only by use of molecular markers. Here we introduce methods for the joint estimation of the two-gene and four-gene coefficients of relationship from data on codominant molecular markers in randomly mating populations. In a comparison with other published estimators of pairwise relatedness, we find these new "regression" estimators to be computationally simpler and to yield similar or lower sampling variances, particularly when many loci are used or when loci are hypervariable. Two examples are given in which the new estimators are applied to natural populations, one that reveals isolation-by-distance in an annual plant and the other that suggests a genetic basis for a coat color polymorphism in bears. 相似文献
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Chandler D Bailey AS Tatchell GM Davidson G Greaves J Grant WP 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1573):1987-1998
Over the past 50 years, crop protection has relied heavily on synthetic chemical pesticides, but their availability is now declining as a result of new legislation and the evolution of resistance in pest populations. Therefore, alternative pest management tactics are needed. Biopesticides are pest management agents based on living micro-organisms or natural products. They have proven potential for pest management and they are being used across the world. However, they are regulated by systems designed originally for chemical pesticides that have created market entry barriers by imposing burdensome costs on the biopesticide industry. There are also significant technical barriers to making biopesticides more effective. In the European Union, a greater emphasis on Integrated Pest Management (IPM) as part of agricultural policy may lead to innovations in the way that biopesticides are regulated. There are also new opportunities for developing biopesticides in IPM by combining ecological science with post-genomics technologies. The new biopesticide products that will result from this research will bring with them new regulatory and economic challenges that must be addressed through joint working between social and natural scientists, policy makers and industry. 相似文献