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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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膳食炎症指数(DII)来源于将饮食和炎症联系起来的文献,被开发用来量化饮食的整体炎症潜能。饮食在调节慢性炎症中起着核心作用,是重要的调节因子,如果饮食的炎症潜能很高,则能够激发免疫调节作用,引起慢性炎症。DII可用于评估和指导个人饮食计划。本研究收集国外相关文献,就DII与炎症之间的相关性予以综述,以期通过减少饮食中的炎性成分而对慢性炎症引起的相关疾病进行一级预防。  相似文献   
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本文回顾了Er:YAG激光活化根管冲洗技术的最新研究进展,包括光子诱导光声流(photon initiated photoacoustic streaming,PIPS)技术和冲击波增强发射光声流(shock wave enhanced emission photoacoustic streaming,SWEEPS)技术,探讨Er:YAG激光预处理桩道的原理、优点以及对纤维桩粘接强度的影响,以期为临床选择适宜的桩道处理方法提供新思路。  相似文献   
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Cheryl L. Rock PhD  RD  Cynthia A. Thomson PhD  RD  Kristen R. Sullivan MS  MPH  Carol L. Howe MD  MLS  Lawrence H. Kushi ScD  Bette J. Caan DrPH  Marian L. Neuhouser PhD  RD  Elisa V. Bandera MD  PhD  Ying Wang PhD  Kimberly Robien PhD  RD  Karen M. Basen-Engquist PhD  MPH  Justin C. Brown PhD  Kerry S. Courneya PhD  Tracy E. Crane PhD  RDN  David O. Garcia PhD  FACSM  Barbara L. Grant MS  RDN  CSO  FAND  Kathryn K. Hamilton MA  RDN  CSO  CDN  FAND  Sheri J. Hartman PhD  Stacey A. Kenfield ScD  Maria Elena Martinez PhD  Jeffrey A. Meyerhardt MD  MPH  Larissa Nekhlyudov MD  MPH  Linda Overholser MD  Alpa V. Patel PhD  Bernardine M. Pinto PhD  Mary E. Platek PhD  RD  CDN  Erika Rees-Punia PhD  MPH  Colleen K. Spees PhD  MEd  RD  LD  FAND  Susan M. Gapstur PhD  Marjorie L. McCullough ScD  RD 《CA: a cancer journal for clinicians》2022,72(3):230-262
The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.  相似文献   
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Objective: Longitudinal data on cardiometabolic effects of egg intake during adolescence are lacking. The current analyses aim to evaluate the impact of usual adolescent egg consumption on lipid levels, fasting glucose, and insulin resistance during late adolescence (age 17–20?years).

Methods: Data from 1392 girls, aged 9 to 10 at baseline and followed for 10?years, in the National Heart, Lung, and Blood Institute’s National Growth and Health Study were used to examine the association between usual egg intake alone and in combination with other healthy lifestyle factors and late adolescent lipid levels, fasting glucose, and insulin resistance, measured as homeostasis model assessment of insulin resistance (HOMA-IR). Diet was assessed using 3-day food records during eight examination cycles. Girls were classified according to usual weekly egg intake, ages 9–17?years:?<1 egg/wk (n?=?361), 1 to <3 eggs/wk (n?=?703), and ≥3 eggs/wk (n?=?328). Analysis of covariance modeling was used to control for confounding by other behavioral and biological risk factors.

Results: Girls with low, moderate, and high egg intakes had adjusted low-density lipoprotein cholesterol levels of 99.7, 98.8, and 95.5 mg/dL, respectively (p?=?0.0778). In combination with higher intakes of fiber, dairy, or fruits and vegetables, these beneficial effects were stronger and statistically significant. There was no evidence that ≥3 eggs/wk had an adverse effect on lipids, glucose, or HOMA-IR. More active girls who consumed ≥3 eggs/wk had the lowest levels of insulin resistance.

Conclusion: These results suggest that eggs may be included as part of a healthy adolescent diet without adverse effects on glucose, lipid levels, or insulin resistance.  相似文献   

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Chronic progressive external ophthalmoplegia (CPEO) is a frequent clinical manifestation of disorders caused by pathogenic mitochondrial DNA mutations. However, for diagnostic purposes skeletal muscle tissue is used, since extraocular muscle tissue is usually not available for work-up. In the present study we aimed to identify causative factors that are responsible for extraocular muscle to be primarily affected in CPEO. We performed comparative histochemical and molecular genetic analyses of extraocular muscle and skeletal muscle single fibers in a case of isolated CPEO caused by the heteroplasmic m.5667G>A mutation in the mitochondrial tRNAAsn gene (MT-TN). Histochemical analyses revealed higher proportion of cytochrome c oxidase deficient fibers in extraocular muscle (41%) compared to skeletal muscle (10%). However, genetic analyses of single fibers revealed no significant difference either in the mutation loads between extraocular muscle and skeletal muscle cytochrome c oxidase deficient single fibers (extraocular muscle 86% ± 4.6%; skeletal muscle 87.8 %± 5.7%, p = 0.246) nor in the mutation threshold (extraocular muscle 74% ± 3%; skeletal muscle 74% ± 4%). We hypothesize that higher proportion of cytochrome c oxidase deficient fibers in extraocular muscle compared to skeletal muscle might be due to facilitated segregation of the m.5667G>A mutation into extraocular muscle, which may explain the preferential ocular manifestation and clinically isolated CPEO.  相似文献   
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目的 研究视神经炎患者的临床特征及早期视盘和黄斑的改变。方法 回顾性分析山西省眼科医院视神经炎患者67例85眼。分析患者基本情况、眼科检查结果及OCT检查结果。结果 67例85眼中,男24例,女43例;28例(41.8%)发生于冬季;49眼(57.6%)入院时最佳矫正视力小于1.7 logMAR。视神经脊髓炎抗体阳性者出院和入院时的最佳矫正视力均较髓鞘少突胶质糖蛋白抗体阳性者差。患眼较健眼视盘周围神经纤维层增厚,杯盘面积比、杯盘垂直比、杯盘水平比、杯容积减小,盘沿面积、视盘面积增大(均为P=0.000);与健眼相比,患眼早期上方、下方和平均黄斑区神经节细胞层厚度及黄斑区神经节细胞复合体的局部丢失体积、整体丢失体积均未发生明显改变(均为P>0.05)。视盘水肿与患眼平均视盘周围神经纤维层厚度存在正相关(r=0.728,P=0.000)。结论 视神经炎多发生于女性,早期视力损害严重,视神经脊髓炎抗体阳性者视力预后差。早期由于视盘水肿,视盘周围神经纤维层增厚,盘沿面积、视盘面积增大;杯容积、杯盘比减小,早期病变未累及黄斑区。  相似文献   
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