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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Kevin R. Keene Luc van Vught Nienke M. van de Velde Isabeau A. Ciggaar Irene C. Notting Stijn W. Genders Jan J.G.M. Verschuuren Martijn R. Tannemaat Hermien E. Kan Jan‐Willem M. Beenakker 《NMR in biomedicine》2021,34(1)
Although quantitative MRI can be instrumental in the diagnosis and assessment of disease progression in orbital diseases involving the extra‐ocular muscles (EOM), acquisition can be challenging as EOM are small and prone to eye‐motion artefacts. We explored the feasibility of assessing fat fractions (FF), muscle volumes and water T2 (T2water) of EOM in healthy controls (HC), myasthenia gravis (MG) and Graves' orbitopathy (GO) patients. FF, EOM volumes and T2water values were determined in 12 HC (aged 22‐65 years), 11 MG (aged 28‐71 years) and six GO (aged 28‐64 years) patients at 7 T using Dixon and multi‐echo spin‐echo sequences. The EOM were semi‐automatically 3D‐segmented by two independent observers. MANOVA and t‐tests were used to assess differences in FF, T2water and volume of EOM between groups (P < .05). Bland–Altman limits of agreement (LoA) were used to assess the reproducibility of segmentations and Dixon scans. The scans were well tolerated by all subjects. The bias in FF between the repeated Dixon scans was ?0.7% (LoA: ±2.1%) for the different observers; the bias in FF was ?0.3% (LoA: ±2.8%) and 0.03 cm3 (LoA: ± 0.36 cm3) for volume. Mean FF of EOM in MG (14.1% ± 1.6%) was higher than in HC (10.4% ± 2.5%). Mean muscle volume was higher in both GO (1.2 ± 0.4 cm3) and MG (0.8 ± 0.2 cm3) compared with HC (0.6 ± 0.2 cm3). The average T2water for all EOM was 24.6 ± 4.0 ms for HC, 24.0 ± 4.7 ms for MG patients and 27.4 ± 4.2 ms for the GO patient. Quantitative MRI at 7 T is feasible for measuring FF and muscle volumes of EOM in HC, MG and GO patients. The measured T2water was on average comparable with skeletal muscle, although with higher variation between subjects. The increased FF in the EOM in MG patients suggests that EOM involvement in MG is accompanied by fat replacement. The unexpected EOM volume increase in MG may provide novel insights into underlying pathophysiological processes. 相似文献
992.
One of the most curious findings emerged from genome-wide studies over the last decade was that genetic mosaicism is a dominant feature of human ageing genomes. The clonal dominance of genetic mosaicism occurs preceding the physiological and physical ageing and associates with propensity for diseases including cancer, Alzheimer’s disease, cardiovascular disease and diabetes. These findings are revolutionizing the ways biologists thinking about health and disease pathogenesis. Among all mosaic mutations in ageing genomes, mosaic chromosomal alterations (mCAs) have the most significant functional consequences because they can produce intercellular genomic variations simultaneously involving dozens to hundreds or even thousands genes, and therefore have most profound effects in human ageing and disease etiology. Here, we provide a comprehensive picture of the landscapes, causes, consequences and rejuvenation of mCAs at multiple scales, from cell to human population, by reviewing data from cytogenetic, genetic and genomic studies in cells, animal models (fly and mouse) and, more frequently, large-cohort populations. A detailed decoding of ageing genomes with a focus on mCAs may yield important insights into the genomic architecture of human ageing, accelerate the risk stratification of age-related diseases (particularly cancers) and development of novel targets and strategies for delaying or rejuvenating human (genome) ageing. 相似文献
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995.
Samuel Legeay Marion Rodier Laetitia Fillon Sébastien Faure Nicolas Clere 《Nutrients》2015,7(7):5443-5468
Obesity and being overweight are linked with a cluster of metabolic and vascular disorders that have been termed the metabolic syndrome. This syndrome promotes the incidence of cardiovascular diseases that are an important public health problem because they represent a major cause of death worldwide. Whereas there is not a universally-accepted set of diagnostic criteria, most expert groups agree that this syndrome is defined by an endothelial dysfunction, an impaired insulin sensitivity and hyperglycemia, dyslipidemia, abdominal obesity and hypertension. Epidemiological studies suggest that the beneficial cardiovascular health effects of diets rich in green tea are, in part, mediated by their flavonoid content, with particular benefits provided by members of this family such as epigallocatechin gallate (EGCG). Although their bioavailability is discussed, various studies suggest that EGCG modulates cellular and molecular mechanisms of various symptoms leading to metabolic syndrome. Therefore, according to in vitro and in vivo model data, this review attempts to increase our understanding about the beneficial properties of EGCG to prevent metabolic syndrome. 相似文献
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目的 综合分析新疆心脑血管疾病总治疗费用现状,为医疗资源的合理配置提供理论依据。方法 通过多阶段分层随机抽样,收集2017年新疆心脑血管疾病患者样本信息。在SHA 2011框架下,采用自上而下的分摊方法,核算心脑血管疾病的治疗费用。建立线性回归模型,用以分析住院费用的影响因素。结果 心脑血管疾病总治疗费用达105.74亿元;占比67.22%的治疗费用发生在综合医院;排名前三位的疾病分别为冠心病、高血压和脑梗塞,占比达74.20%;65岁及以上老年人群花费占比为43.51%;县(区)级机构(t = - 218.362,P<0.001)、市级机构(t = - 103.65,P<0.001)、住院天数(t = 233.297,P<0.001)、65岁以上人群(t = 58.422,P<0.001)、手术情况(t = 101.514,P<0.001)均是影响住院费用的主要因素。结论 新疆心脑血管疾病消耗大量医疗资源;防控工作重点关注老年人群;治疗费用机构流向有待优化,应强化基层医疗机构在防治慢病工作中的主导作用;缩短住院时间是有效控制治疗费用的直接途径。 相似文献
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Clostridioides (Clostridium) difficile (C. difficile) infection is one of the most common causes of increased morbidity and mortality. Approximately 500 000 C. difficile infections (CDIs) occur each year in the United States, and they result in more than 29 000 deaths. Patients with haematologic diseases are at a higher risk for this infection due to frequent hospitalization and exposure to treatment-associated risk factors. Whilst several currently available antimicrobial agents offer resolution, recurrence of infection remains a major concern. Recent advancement in deciphering C. difficile virulence mechanisms and identification of its allies in contributing to the infection has led to the development of alternative treatment strategies. Here, we will provide a contemporary discussion of how major risk factors in haematologic diseases, such as immunosuppression, chemoradiation, use of antibiotic, proton pump inhibitor and opioid, and deficiency in butyrate and antimicrobial peptides contribute to C. difficile infection. Next, we will highlight different approaches to control and mitigate this infection such as antibiotic stewardship and faecal microbiota transplantation. Finally, we will explore several emerging treatments such as use of pre- and probiotics, immunotherapy and microbiome-sparing agents. 相似文献