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1.
视觉通路包括视神经、视交叉、视束、视放射及视皮质。常规磁共振检查技术难以发现视路损伤后白质纤维微结构改变,眼科学检查也存在一定的局限性及主观性,且不能探测后视路的变化。弥散张量成像(diffusion tensor imaging,DTI)作为一种新兴的磁共振成像技术,通过各种后处理分析方法结合不同的参数进行分析,可提供组织的微结构信息,并能够直观显示活体白质纤维束,在无创地探索疾病的神经病理机制、评估预后方面起着重要的作用。近年来随着DTI后处理方法的不断创新,其在视路损伤中的研究越来越多。本文在介绍DTI的主要参数及常见脑白质微结构分析方法的同时,阐述了其在视路损伤研究中的应用,并进一步对各种分析方法的优缺点进行总结。 相似文献
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Derek K. Chu Romina Brignardello-Petersen Gordon H. Guyatt Cristian Ricci Jon Genuneit 《Pediatric allergy and immunology》2022,33(1):e13609
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care. 相似文献
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目的 以2017年某省食品安全监测大米中砷含量数据为例,探讨空间统计学方法在食品污染物分析中的应用价值。方法 采用空间点模式估计、核密度分析,全局以及局部自相关性分析等空间统计学方法,在县级空间尺度下,对某省大米中砷含量进行探索性空间数据分析。结果 空间点模式分布图显示,该省大米砷污染的空间分布比较分散,核密度分析结果显示污染热点区域主要在该省中东部地区。全局自相关Moran''s I指数值为0.11,有统计学意义,大米样品中砷污染呈现出低度空间聚集性。有1个"高-高"聚集区,2个典型的"低-低"聚集区。结论 空间统计学运用于食物污染物分布研究上,可以很好地可视化展示、识别污染分布规律、热点地区和聚集区,为基于问题的监测工作的开展提供技术支持。 相似文献
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Lingxu Jiang Yingwan Luo Shuanghong Zhu Lu Wang Liya Ma Hua Zhang Chuying Shen Wenli Yang Yanling Ren Xinping Zhou Chen Mei Li Ye Weilai Xu Haiyang Yang Chenxi Lu Jie Jin Hongyan Tong 《Cancer science》2020,111(2):580-591
Patients with lower‐risk myelodysplastic syndromes (LR‐MDS) as defined by the International Prognostic Scoring System (IPSS) have more favorable prognosis in general, but significant inter‐individual heterogeneity exists. In this study, we examined the molecular profile of 15 MDS‐relevant genes in 159 patients with LR‐MDS using next‐generation sequencing. In univariate COX regression, shorter overall survival (OS) was associated with mutation status of ASXL1 (P = .001), RUNX1 (P = .031), EZH2 (P = .049), TP53 (P = .016), SRSF2 (P = .046), JAK2 (P = .040), and IDH2 (P = .035). We also found significantly shorter OS in patients with an adjusted TET2 variant allele frequency (VAF) ≥18% versus those with either an adjusted TET2 VAF <18% or without TET2 mutations (median: 20.4 vs 47.8 months; P = .020; HR = 2.183, 95%CI: 1.129‐4.224). After adjustment for IPSS, shorter OS was associated with mutation status of ASXL1 (P < .001; HR = 4.306, 95% CI: 2.144‐8.650), TP53 (P = .004; HR = 4.863, 95% CI: 1.662‐14.230) and JAK2 (P = .002; HR = 5.466, 95%CI: 1.848‐16.169), as well as adjusted TET2 VAF ≥18% (P = .008; HR = 2.492, 95% CI: 1.273‐4.876). Also, OS was increasingly shorter as the number of mutational factors increased (P < .001). A novel prognostic scoring system incorporating the presence/absence of the four independent mutational factors into the IPSS further stratified LR‐MDS patients into three prognostically different groups (P < .001). The newly developed scoring system redefined 10.1% (16/159) of patients as a higher‐risk group, who could not be predicted by the currently prognostic models. In conclusion, integration of the IPSS with mutation status/burden of certain MDS‐relevant genes may improve the prognostication of patients with LR‐MDS and could help identify those with worse‐than‐expected prognosis for more aggressive treatment. 相似文献
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《Health & place》2019
Multilevel models have long been used by health geographers working on questions of space, place, and health. Similarly, health geographers have pursued interests in determining whether or not the effect of an exposure on a health outcome varies spatially. However, relatively little work has sought to use multilevel models to explore spatial variability in the effects of a contextual exposure on a health outcome. Methodologically, extending multilevel models to allow intercepts and slopes to vary spatially is straightforward. The purpose of this paper, therefore, is to show how multilevel spatial models can be extended to include spatially varying covariate effects. We provide an empirical example on the effect of agriculture on malaria risk in children under 5 years of age in the Democratic Republic of Congo. 相似文献
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目的:研究高频电针(100Hz)结合膝关节腔内注射臭氧对膝骨关节炎(KOA)患者血清IL-1及TNF-α水平的影响。方法:将195例KOA患者随机分为三组,100 Hz电针治疗组(A组,n=65); 膝关节腔内臭氧注射治疗组(B组,n=65); 100 Hz电针结合膝关节腔内臭氧注射治疗组(C组,n=65),疗程均为3周。分别于治疗前和治疗后检测患者血清IL-1及TNF-α水平,并进行WOMAC 指数评分。结果:治疗后,三组患者的血清IL-1、TNF-α含量均较治疗开始前有所降低; 且C 组改善水平优于A、B 组,B组改善水平优于A组,差异均具有统计学意义(P<0.05); 治疗后,三组患者WOMAC 指数评分均较治疗前有所降低; 且C 组WOMAC评分好于A和B 组,B 组WOMAC评分优于A 组,差异均有统计学意义(P<0.05)。结论:高频电针结合膝关节腔内注射臭氧可显著抑制KOA患者血清 IL-1、TNF-α的表达,改善患者WOMAC指数评分。 相似文献
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目的 通过检测胆囊癌患者β-纤维蛋白原(Fgβ)-455G/A基因,探讨Fgβ-455G/A基因多态性与胆囊癌的相关性。方法 采集50 例胆囊癌患者(胆囊癌组)和50 例胆囊结石伴慢性胆囊炎患者(胆囊炎组)的静脉血,应用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)方法对Fgβ-455进行基因分型。 结果 Fgβ-455 基因GA杂合型和AA纯合子在胆囊癌中的频率显著高于胆囊炎组,显著增加胆囊癌发生的危险性,OR值(95%CI)分别为2.526(1.052~6.068)和4.306(1.177~15.749)。结论 Fgβ-455G/A位点G/A单个碱基的改变可能在胆囊癌的发病中起着重要的作用。 相似文献
9.
Qingyang Xiao Yitian Zhou Stefan Winter Florian Büttner Elke Schaeffeler Matthias Schwab Volker M. Lauschke 《International journal of cancer. Journal international du cancer》2020,146(9):2475-2487
Multidrug resistance due to facilitated drug efflux mediated by ATP-binding cassette (ABC) transporters is a main cause for failure of cancer therapy. Genetic polymorphisms in ABC genes affect the disposition of chemotherapeutics and constitute important biomarkers for therapeutic response and toxicity. Here we correlated germline variability in ABC transporters with disease-specific survival (DSS) in 960 breast cancer (BRCA), 314 clear cell renal cell carcinoma and 325 hepatocellular carcinoma patients. We find that variant burden in ABCC1 is a strong predictor of DSS in BRCA patients, whereas candidate polymorphisms are not associated with DSS. This association is highly drug-specific for subgroups treated with the MRP1 substrates cyclophosphamide (log-rank p = 0.0011) and doxorubicin (log-rank p = 0.0088) independent of age and tumor stage, whereas no association was found in individuals treated with tamoxifen (log-rank p = 0.13). Structural mapping of significant variants revealed multiple variants at residues involved in protein stability, cofactor stabilization or substrate binding. Our results demonstrate that BRCA patients with high variant burden in ABCC1 are less prone to respond appropriately to pharmacological therapy with MRP1 substrates, thus incentivizing the consideration of genomic germline data for precision cancer medicine. 相似文献
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