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41.
Lauren E. Barber Kimberly A. Bertrand Shanshan Sheehy Laura F. White Hemant K. Roy Lynn Rosenberg Julie R. Palmer Jessica L. Petrick 《International journal of cancer. Journal international du cancer》2023,153(12):1978-1987
Evidence suggests that aspirin use reduces the occurrence of colorectal neoplasia. Few studies have investigated the association among Black Americans, who are disproportionately burdened by the disease. We assessed aspirin use in relation to colorectal adenoma among Black women. The Black Women's Health Study is a prospective cohort of self-identified Black American women established in 1995. Participants reported regular aspirin use on baseline and follow-up questionnaires. Beginning in 1999, participants reported undergoing a colonoscopy or sigmoidoscopy, the only procedures through which colorectal adenomas can be diagnosed. Multivariable logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations between aspirin use and colorectal adenoma among 34 397 women who reported at least 1 colonoscopy or sigmoidoscopy. From 1997 through 2018, 1913 women were diagnosed with an adenoma. Compared to nonaspirin users, regular users had 14% (OR = 0.86, 95% CI: 0.78-0.95) lower odds of adenoma. The odds of adenoma decreased with increasing duration of aspirin use (≥10 years: OR = 0.80, 95% CI: 0.66-0.96). Initiating aspirin at a younger age was associated with a reduced adenoma occurrence (age < 40 years at initiation: OR = 0.69, 95% CI: 0.55-0.86). Regular aspirin use was associated with a decreased odds of colorectal adenoma in our study of Black women. These findings support evidence demonstrating a chemopreventive impact of aspirin on colorectal neoplasia and suggest that aspirin may be a useful prevention strategy among US Black women. 相似文献
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A Coupled FEM-BEM Approach for the Solution of the Free-Boundary Axi-Symmetric Plasma Equilibrium Problem 下载免费PDF全文
M. Bonotto D. Abate P. Bettini & F. Villone 《Communications In Computational Physics》2022,31(1):27-59
In this paper we present a coupled Finite Element Method – Boundary Element Method (FEM-BEM) approach for the solution of the free-boundary axi-symmetric
plasma equilibrium problem. The proposed method, obtained from an improvement
of the Hagenow-Lackner coupling method, allows to efficiently model the equilibrium
problem in unbounded domains by discretizing only the plasma region; the external
conductors can be modelled either as 2D or 3D models, according to the problem of interest. The paper explores different iterative methods for the solution of the nonlinear
Grad-Shafranov equation, such as Picard, Newton-Raphson and Newton-Krylov, in order to provide a robust and reliable tool, able to handle large-scale problems (e.g. high
resolution equilibria). This method has been implemented in the FRIDA code (FRee-boundary Integro-Differential Axisimmetric – https://github.
om/matteobonotto/
FRIDA), together with a suitable Adaptive Integration Technique (AIT) for the computation of the source term. FRIDA has been successfully tested and validated against
experimental data from RFX-mod device, and numerical equilibria of an ITER-like device. 相似文献
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目的分析不同CT征象在周围型肺癌(PLC)诊断中的价值。 方法选择2018年6月至2022年2月我院诊治的PLC患者53例,分析患者的多层螺旋CT(MSCT)征象。采用卡方检验筛选出在不同组织病理类型PLC中有意义的CT征象,采用多元Logistic筛选出特定PLC类型中更多及更少出现的CT征象,绘制上述CT征象对特定PLC类型的诊断价值的ROC曲线。 结果空泡征、深分叶征、磨玻璃征、空气支气管征、毛刺征、胸膜凹陷征、支气管血管集束征,在不同组织病理类型的PLC患者中存在差异(P<0.05);腺癌更多出现空泡征,鳞癌更多出现深分叶征,鳞癌更少出现磨玻璃征,腺癌更容易出现毛刺征,腺癌更容易出现支气管血管集束征(P<0.05);多个CT征象的联合可进一步提高特定组织病理类型PLC的诊断正确率(P<0.05)。 结论不同组织病理类型的PLC具有不同特点的CT征象,多种CT征象的联合有助于进一步确诊特定组织病理类型的PLC。 相似文献
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