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71.
72.
目的:通过比较表观扩散系数(ADC 值)及相位值,探讨3.0 T 磁共振扩散加权成像技术(DWI)和磁敏感加权成像技术(SWI)对不同年龄段正常脑深部核团的水分子弥散及铁分布的研究价值。方法健康受试者32例纳入研究,分为青年组、中年组、老年组,行 DWI、SWI 检查,测量黑质、红核、齿状核、尾状核头、壳核、苍白球的 ADC 值及相位位移值,计算相位值。结果青年组与老年组的尾状核头、壳核及苍白球 ADC 值,黑质、壳核、苍白球、齿状核相位值的差异有统计学意义(P 分别为0.025、0.000、0.004、0.008、0.006、0.002、0.037);青年组与中年组的壳核 ADC 值,壳核、苍白球相位值的差异有统计学意义(P 分别为0.010、0.007、0.013);中年组与老年组的黑质相位值的差异有统计学意义(P 为0.030)。壳核、尾状核头 ADC 值与年龄呈正相关;黑质、红核、齿状核、尾状核头、壳核、苍白球相位值与年龄呈负相关。结论DWI 及 SWI 可以分别反映年龄对脑深部核团水分子扩散和铁分布的影响。 相似文献
73.
Chronic obstructive pulmonary disease (COPD) is the fourth and third leading cause of death worldwide and in China, respectively. Sedentary behavior has been shown to increase the risk of respiratory disease, such as asthma. However, the relationship between sedentary behavior and COPD is unclear. This study aimed to investigate the association between sedentary behavior and COPD.Data was extracted from the 2018 a large-scale cross-sectional study of Chronic Disease and Lifestyle Population Survey in Sichuan Province of China, in which sedentary behavior and chronic diseases were self-reported according to medical records. The association between sedentary behavior on risk of COPD was estimated using multivariable regression model in non-matching cohorts and generalized propensity score-weighted (GPSW)cohorts, respectively, controlling for potential confounders.Individuals who remained sedentary for more than 7 hours per day were more likely to have COPD than the control group (<3 hours) both in conventional multivariate logistic regression analysis (OR = 2.020, 95%CI: 1.575–2.585, P < .001) and GPSW analysis (OR = 2.381, 95%CI: 1.778–3.188, P < .001). After GPSW and the sensitivity analysis using refined smoking variable further found a dose-effect between sedentary behavior and COPD, with 1.242 (95%CI: 1.006–1.532, P < .05) times risk of COPD in those sedentary behavior of more than 5 hours per day (GPSW) and 1.377 (95%CI: 1.092–1.736, P < .05) times risk in those sedentary behavior above 5 hours per day (sensitivity analysis), comparing with the control group.Sedentary behavior is independently associated with increased risk of COPD, adjusting for other confounders. The findings of this study have important implications for future research and public health guidance. Reducing sedentary time may have a significant role in COPD prevention. 相似文献
74.
Thyroid cancer is a common endocrine malignancy; however, surgery remains its primary treatment option. A novel targeted drug for the development and application of targeted therapy in thyroid cancer treatment remain underexplored.We obtained RNA sequence data of thyroid cancer from The Cancer Genome Atlas database and identified differentially expressed genes (DEGs). Then, we constructed co-expression network with DEGs and combined it with differentially methylation analysis to screen the key genes in thyroid cancer. PockDrug-Server, an online tool, was applied to predict the druggability of the key genes. Finally, we constructed protein-protein interaction (PPI) network to observe potential targeted drugs for thyroid cancer.We identified 3 genes correlated with altered DNA methylation level and oncogenesis of thyroid cancer. According to the druggable analysis and PPI network, we predicted TRAF2 and NCK-interacting protein kinase (TNIK) sever as the drug targeted for thyroid cancer. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that genes in protein-protein interaction network of TNIK enriched in mitogen-activated protein kinase signaling pathway. For drug repositioning, we identified a targeted drug of genes in PPI network.Our study provides a bioinformatics method for screening drug targets and provides a theoretical basis for thyroid cancer targeted therapy. 相似文献
75.
《JACC: Cardiovascular Imaging》2022,15(5):796-808
ObjectivesThis systematic review and meta-analysis investigated the association of diabetes and glycemic control with myocardial fibrosis (MF).BackgroundMF is associated with an increased risk of heart failure, coronary artery disease, arrhythmias, and death. Diabetes may influence the development of MF, but evidence is inconsistent.MethodsThe authors searched EMBASE, Medline Ovid, Cochrane CENTRAL, Web of Science, and Google Scholar for observational and interventional studies investigating the association of diabetes, glycemic control, and antidiabetic medication with MF assessed by histology and cardiac magnetic resonance (ie, extracellular volume fraction [ECV%] and T1 time).ResultsA total of 32 studies (88% exclusively on type 2 diabetes) involving 5,053 participants were included in the systematic review. Meta-analyses showed that diabetes was associated with a higher degree of MF assessed by histological collagen volume fraction (n = 6 studies; mean difference: 5.80; 95% CI: 2.00-9.59) and ECV% (13 studies; mean difference: 2.09; 95% CI: 0.92-3.27), but not by native or postcontrast T1 time. Higher glycosylated hemoglobin levels were associated with higher degrees of MF.ConclusionsDiabetes is associated with higher degree of MF assessed by histology and ECV% but not by T1 time. In patients with diabetes, worse glycemic control was associated with higher MF degrees. These findings mostly apply to type 2 diabetes and warrant further investigation into whether these associations are causal and which medications could attenuate MF in patients with diabetes. 相似文献
76.
77.
目的:探讨3.0T磁共振(MRI)弥散加权成像(DWI)量化指标对肾脏肿瘤性病变的诊断和鉴别诊断价值。方法:收集行肾脏MRI检查并经病理确诊的肾脏实质肿瘤89例。其中,肾细胞癌60例,包括39例肾透明细胞癌、8例乳头状肾细胞癌、9例肾嫌色细胞癌、4例多房囊性肾细胞癌;良性病变29例,包括肾血管平滑肌脂肪瘤25例,嗜酸细胞瘤4例。所有患者采用GE Signa HD 3.0T MR进行横断面DWI成像并行表观弥散系数(apparent diffusion coefficient,ADC)值测量。结果:肾透明细胞癌、乳头状肾细胞癌、肾嫌色细胞癌、多房囊性肾细胞癌ADC平均值分别为(1.681 5±0.176 9)×10~(-3)、(1.165 0±0.217 0)×10~(-3)、(1.121 0±0.231 6)×10~(-3)、(2.030 0±0.235 1)×10~(-3) mm~2/s,肾血管平滑肌脂肪瘤、肾嗜酸细胞瘤ADC平均值分别为(1.155 2±0.132 0)×10~(-3)、(1.580 0±0.212 3)×10~(-3) mm~2/s。肾透明细胞癌ADC值与乳头状肾细胞癌、肾嫌色细胞癌、肾血管平滑肌脂肪瘤ADC值差异均有统计学意义(P=0.000);而与多房囊性肾细胞癌、肾嗜酸细胞瘤ADC值差异无统计意义。结论:3.0T MR-DWI成像ADC值对肾脏肿瘤性病变具有鉴别诊断价值,有利于指导患者治疗方案的选择。 相似文献
78.
Virginie Pécourneau Yannick Degboé Thomas Barnetche Alain Cantagrel Arnaud Constantin Adeline Ruyssen-Witrand 《Archives of physical medicine and rehabilitation》2018,99(2):383-389.e1
Objective
To assess the effectiveness of exercise programs on disease activity and function in ankylosing spondylitis (AS) by a systematic review and meta-analysis of randomized controlled trials (RCTs).Data Sources
Medline via PubMed and Cochrane Library.Study Selection
Reports of RCTs examining the effectiveness of exercise programs for AS published up to May 2017.Data Extraction
Outcomes were evolution of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI) after the completion of exercise programs. Modalities of exercise were compared and the use of biologic therapy was reported.Data Synthesis
After screening 190 abstracts, we selected 26 reports for detailed evaluation and finally investigated 8 trials that assessed a home-based exercise program (2/8), swimming (1/8), Pilates training (1/8), or supervised exercises (4/8), for a total of 331 patients with AS. Four trials included patients receiving antitumor necrosis factor therapy. All trials except one showed a decrease in BASDAI and BASFI with exercise. The weighted mean difference was ?0.90 (95% confidence interval, ?1.52 to ?0.27; I2=69%; P=.005) for the BASDAI and ?0.72 (95% confidence interval, ?1.03 to ?0.40; I2=0%; P<.00001) for the BASFI in favor of exercise programs.Conclusions
Despite the small number of patients and the heterogeneity of exercise programs in the RCTs included in this meta-analysis, its results support the potential of exercise programs to improve disease activity and body function in AS. 相似文献79.
Vikram Kumar Yeragani Arindam Barua Indu Sattiraju Nikhil Mallavarapu 《Cardiovascular Engineering》2003,3(4):141-146
In this study, we evaluated the effectiveness of the statistic, Weighted Coherence in relation to the average or mean coherence in a particular frequency band after cross-spectral analysis. In time domain, correlation coefficient explains the relationship between two variables of interest, and a similar statistic in frequency domain using cross-spectral analysis is referred to as coherence, which is equivalent to the squared correlation coefficient and ranges from zero to unity. In this study, we show that weighted coherence is much more sensitive to various challenges within the same subject and also may be a more sensitive indicator of group differences in different frequency bands. Our data on normal subjects and patients with panic disorder during supine and standing postures during normal breathing, and also at different breathing rates throw new light on the sensitivity of this previously described novel index to quantify coherence between two related time series such as beat-to-beat heart rate and QT interval. 相似文献
80.
目的探讨磁敏感加权成像(SWI)对颅脑外伤患者诊断符合率的影响。方法选取2017年6月~2019年7月某院颅脑外伤患者80例作为研究对象。均行CT平扫、SWI检查,以手术结果作为“金标准”,对比两种检查方案病灶检出数量、病灶部位,分析SWI检查对颅脑外伤诊断符合率的影响。结果CT示脑挫裂伤低密度影伴高密度影、脑出血类圆形高密度影、急性期硬膜下血肿新月形高密度影;SWI示颅内出血低信号,附近水肿带示高信号,脑室及蛛网膜下腔出血呈点样、线状低信号,弥漫性轴索损伤微小出血灶低信号;SWI检查脑挫裂伤并血肿、复合外伤符合率及颅脑外伤总符合较CT高(P<0.05)。结论SWI检查在颅脑外伤中有特异性影像学表现,且能显示弥漫性轴索损伤微小出血灶,进一步提高诊断符合率,可为临床诊断、制定治疗方案提供数据支持。 相似文献