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AimsPatient factors affect the risk of radiotherapy toxicity, but many are poorly defined. Studies have shown that race affects cancer incidence, survival, drug response, molecular pathways and epigenetics. Effects on radiosensitivity and radiotherapy toxicity are not well studied. The aim of the present study was to identify the effects of race and ethnicity on the risk of radiotherapy toxicity.Materials and methodsA systematic review was carried out of PubMed, Ovid Medline and Ovid Embase with no year limit. PRISMA 2020 guidelines were followed. Two independent assessors reviewed papers.ResultsOf 607 papers screened, 46 fulfilled the inclusion criteria. Papers were published between 1996 and 2021 and involved 30–28,354 individuals (median 433). Most involved patients with prostate (33%), breast (26%) and lung (9%) cancer. Both early and late toxicities were studied. Some studies reported a higher risk of toxicity in White men with prostate cancer compared with other races and ethnicities. For breast cancer patients, some reported an increased risk of toxicity in White women compared with other race and ethnic groups. In general, it was difficult to draw conclusions due to insufficient reporting and analysis of race and ethnicity in published literature.ConclusionsReporting of race and ethnicity in radiotherapy studies must be harmonised and improved and frameworks are needed to improve the quality of reporting. Further research is needed to understand how ancestral heritage might affect radiosensitivity and risk of radiotherapy toxicity.  相似文献   
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Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.  相似文献   
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Background and aimsElevated serum ferritin is associated with incident Type 2 diabetes (T2D), but the interactions between serum ferritin and genetic factors which may improve understanding underlying mechanism in the development of T2D are still unclear. We determined the gene–ferritin interactions on the development of T2D by genome-wide gene–ferritin interaction analyses.Methods and resultsA total of 3405 participants from two prospective cohorts of community living residents were included, and the median follow-time was 3.99 years. Genome-wide gene–ferritin interactions were analyzed using the joint test with two degrees of freedom and the interaction test with one degree of freedom. There were 18 SNPs selected in the joint test. Finally, four independent variants [rs355140 (LINC00312), rs4075576 (nearby PDGFA), rs1332202 (PTPRD), and rs713157 (nearby LINC00900)] with low pairwise linkage disequilibrium (r2 < 0.2) and located at least 1000 kb from the index SNP showed interactions with serum ferritin level. In the association analyses between serum ferritin levels (tertiles of ferritin and ferritin status) and the incidence of T2D according to genotype, the Incidence Rate Ratios (IRRs) in the highest tertile of ferritin level (vs. the lowest tertile) were greater for participants with heterozygotes of risk alleles of each of the four SNP than IRRs for those with wild type. Compared with the normal group, the elevated ferritin group also had a higher risk of T2D for all genetic variants of risk alleles, particularly its homozygotes.ConclusionSerum ferritin level interacts with genetic variants (rs355140, rs4075576, rs1332202, and rs713157) in the development of T2D.  相似文献   
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目的 系统整合脑卒中幸存者运动依从性的影响因素。方法 计算机检索PubMed、Web of Science、Cochrane library、Embase、CINAHL、PsycINFO、百度、Google、中国期刊全文数据库、万方数据库、中国生物医学数据库和维普中文期刊数据库中有关脑卒中运动依从性影响因素的相关研究,检索时间自建库至2021年11月15日。2名研究员独立筛选、提取、评价文献,遇到分歧小组协商讨论。结果 纳入符合标准的文献13篇,共提炼出完整的研究主题62个,归纳组合形成6个新的类别,2个综合的整合结果。整合结果1: 影响脑卒中患者运动依从性的个人因素;包括个人动机因素,个人能力因素及个人心理因素;整合结果2:影响脑卒中患者运动依从性的外在因素;包括人际关系因素、康复团队因素及社会系统因素。结论 深入理解影响卒中患者康复运动依从性的驱动和阻碍因素,找准提高康复运动依从性的突破口,进而提高患者的运动积极性,提高其生活质量。  相似文献   
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