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91.
Easton DF Pooley KA Dunning AM Pharoah PD Thompson D Ballinger DG Struewing JP Morrison J Field H Luben R Wareham N Ahmed S Healey CS Bowman R;SEARCH collaborators Meyer KB Haiman CA Kolonel LK Henderson BE Le Marchand L Brennan P Sangrajrang S Gaborieau V Odefrey F Shen CY Wu PE Wang HC Eccles D Evans DG Peto J Fletcher O Johnson N Seal S Stratton MR Rahman N Chenevix-Trench G Bojesen SE Nordestgaard BG Axelsson CK Garcia-Closas M Brinton L Chanock S Lissowska J Peplonska B Nevanlinna H 《Nature》2007,447(7148):1087-1093
Breast cancer exhibits familial aggregation, consistent with variation in genetic susceptibility to the disease. Known susceptibility genes account for less than 25% of the familial risk of breast cancer, and the residual genetic variance is likely to be due to variants conferring more moderate risks. To identify further susceptibility alleles, we conducted a two-stage genome-wide association study in 4,398 breast cancer cases and 4,316 controls, followed by a third stage in which 30 single nucleotide polymorphisms (SNPs) were tested for confirmation in 21,860 cases and 22,578 controls from 22 studies. We used 227,876 SNPs that were estimated to correlate with 77% of known common SNPs in Europeans at r2 > 0.5. SNPs in five novel independent loci exhibited strong and consistent evidence of association with breast cancer (P < 10(-7)). Four of these contain plausible causative genes (FGFR2, TNRC9, MAP3K1 and LSP1). At the second stage, 1,792 SNPs were significant at the P < 0.05 level compared with an estimated 1,343 that would be expected by chance, indicating that many additional common susceptibility alleles may be identifiable by this approach. 相似文献
92.
Effect of silica fume on the fresh and hardened properties of fly ash-based self-compacting geopolymer concrete 下载免费PDF全文
The effect of silica fume on the fresh and hardened properties of fly ash-based self-compacting geopolymer concrete (SCGC) was investigated in this paper. The work focused on the concrete mixes with a fixed water-to-geopolymer solid (W/Gs) ratio of 0.33 by mass and a constant total binder content of 400 kg/m3. The mass fractions of silica fume that replaced fly ash in this research were 0wt%, 5wt%, 10wt%, and 15wt%. The workability-related fresh properties of SCGC were assessed through slump flow, V-funnel, and L-box test methods. Hardened concrete tests were limited to compressive, splitting tensile and flexural strengths, all of which were measured at the age of 1, 7, and 28 d after 48-h oven curing. The results indicate that the addition of silica fume as a partial replacement of fly ash results in the loss of workability; nevertheless, the mechanical properties of hardened SCGC are significantly improved by incorporating silica fume, especially up to 10wt%. Applying this percentage of silica fume results in 4.3% reduction in the slump flow; however, it increases the compressive strength by 6.9%, tensile strength by 12.8% and flexural strength by 11.5%. 相似文献
93.
Nollaig M. Bourke Silvia Napoletano Ciaran Bannan Suaad Ahmed Colm Bergin Áine McKnight Nigel J. Stevenson 《Cellular and molecular life sciences : CMLS》2018,75(5):775-783
Viral infections, including HIV, trigger the production of type I interferons (IFNs), which in turn, activate a signalling cascade that ultimately culminates with the expression of anti-viral proteins. Mounting evidence suggests that type I IFNs, in particular IFN-α, play a pivotal role in limiting acute HIV infection. Highly active anti-retroviral treatment reduces viral load and increases life expectancy in HIV positive patients; however, it fails to fully eliminate latent HIV reservoirs. To revisit HIV as a curable disease, this article reviews a body of literature that highlights type I IFNs as mediators in the control of HIV infection, with particular focus on the anti-HIV restriction factors induced and/or activated by IFN-α. In addition, we discuss the relevance of type I IFN treatment in the context of HIV latency reversal, novel therapeutic intervention strategies and the potential for full HIV clearance. 相似文献
94.
Ahmed M. Warfa 《西北部美国博物学家》2011,58(1)
The current status of Mertensia oblongifolia (Nutt.) G. Don and its allied taxa is surveyed. On the bases of continuously coherent morphological characters and/or regionally correlated variations, more than 30 taxa, including species, subspecies, varieties, and 1 forma, previously considered different from M. oblongifolia , are now placed under synonymy of this species. Those taxa currently known as M. fusiformis Greene, M. bakeri Greene, and M. bakeri var. osterhoutii Williams are among the new synonyms. Typification, taxonomy, and morphological problems of M. oblongifolia are discussed. 相似文献
95.