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991.
《Radiography》2020,26(3):234-239
IntroductionDCE-MRI is established for detecting prostate cancer (PCa). However, it requires a gadolinium contrast agent, with potential risks for patients. The application of DIR-MRI is simple and may allow cancer detection without the use of an intravenous contrast agent by differentially nullifying signal from normal and abnormal prostate tissue, creating contrast between the cancer and background normal prostate. In this pilot study we gathered data from DIR-MRI and DCE-MRI of the prostate for an equivalence trial. We also looked at how the DIR-MRI appearance varies with the aggressiveness of PCa.MethodDIR-MRI and DCE-MRI were acquired. The images were assessed by an experienced Consultant Radiologist and a novice reporter (Radiographer). The potential PCa lesions were quantified using a lesion to normal ratio (LNR). Radiological pathological correlation was made to identify the MRI lesions that represented significant PCa. A Wilcoxon sign rank was used to compare DCE-LNR and DIR-LNR for PCa containing lesions. Pearson's correlation was used to look at the relationship between DIR-LNR and PCa grade group (aggressiveness).ResultsDCE-LNR and DIR-LNR were found to be significantly different (Z = −5.910, p < 0.001). However, a significant correlation was found between PCa grade group and DIR-LNR.ConclusionDIR and DCE sequences are not equivalent and significant cancer is more conspicuous on the DCE sequence. However, DIR-LNR does correlate with PCa aggressiveness.Implications for practiceWith the correlation of PCa grade group with DIR-LNR this may be a useful sequence in evaluation of the prostate; stratifying the risk of there being clinically significant PCa before biopsy is performed. Furthermore, given that DIR-LNR appears to predict PCa aggressiveness DIR might be used as part of a multiparametric MRI protocol designed to avoid biopsy.  相似文献   
992.
BackgroundPrevious studies have assessed the association of neutrophil to lymphocyte ratio (NLR) with cognitive impairment (COI) in clinical settings. Whether NLR is associated with COI among free-living seniors at population level remains unknown.ObjectivesWe aimed to assess the relationship between NLR and COI among community-dwelling older adults and the predictive value of NLR for COI screening in the community.MethodsData of 4579 older adults aged 60 or older in Weitang Geriatric Diseases study, a community-based cross-sectional study conducted in Suzhou located in the east part of China, were analyzed. The NLR was calculated as the absolute neutrophil count divided by the absolute lymphocyte count. Cognitive function of the participants was assessed using the Abbreviated Mental Test.ResultsCompared to those in the first quartile of NLR, older adults in the 4th quartile of NLR had a greater risk of COI (odds ratio = 1.34, 95 % confidence interval = 1.06–1.69). Elevated NLR quartile was associated with increasing risk of COI (p value for trend = 0.02). Addition of NLR to the conventional risk factors model could improve the correct reclassification of COI about 9.0 % (p = 0.02) and integrated discrimination improvement value was 0.0012 (p = 0.09).ConclusionsWe found that elevated NLR was associated with an increased risk of COI and whether NLR may act as a clinically relevant predictor for COI among community-dwelling older adults could not be determined.  相似文献   
993.
目的:探讨过敏性紫癜患儿急性肾损伤(AKI)与中性粒细胞和淋巴细胞比值(NLR)的相关性。方法:回顾性分析2015年3月至2018年6月在我院接受治疗的94 例过敏性紫癜患儿的临床资料,根据是否出现AKI分为AKI组和非AKI组,比较两组患儿的性别、年龄、胱抑素C、血肌酐、C-反应蛋白、尿素氮、尿蛋白、尿茁2 微球蛋白、肾小球滤过率(GFR)和NLR。采用Spearman检验分析NLR与其他临床指标的相关性,采用多元逐步Logistic回归分析法分析发生AKI的危险因素,采用受试者工作曲线(ROC)分析NLR 诊断AKI的价值。结果:94例患儿发生AKI 32例,发生率34.0%。与非AKI组比较,AKI组胱抑素C、血肌酐、C-反应蛋白、尿素氮、尿β2微球蛋白及NLR比值均升高(P均<0.05),而GFR降低(P<0.05)。Spearman分析显示,NLR与胱抑素C、血肌酐、C-反应蛋白、尿素氮、尿β2微球蛋白呈正相关(P均<0.05),与GFR呈负相关(P<0.05)。多元逐步Logistic回归分析显示,高胱抑素C、高血肌酐、高C-反应蛋白及高NLR是发生AKI的危险因素(P均<0.05)。ROC分析显示,当截断值取6.33时,NLR预测AKI发生的曲线下面积、灵敏度和特异度分别为0.845、85.1%和78.2%。结论:高NLR是过敏性紫癜患儿发生AKI的独立危险因素,可能有助于对AKI的早期诊断。  相似文献   
994.
995.
Introduction The spectrum of hypertensive heart disease is wide, and can include left ventricular dysfunction. The development of echocardiographic parameters to improve patient stratification and to identify early adverse changes could be clinically useful.Aim To identify subclinical left ventricular dysfunction in hypertensive subjects with preserved ejection fraction (>55%), identified by global parameters of myocardial strain on speckle tracking imaging.Methods This was a comparative observational study of two groups of individuals: normotensive (n=20, age 59±7 years, 55% male) and hypertensive (n=229, age 62±12 years, 57% male). Left ventricular function was assessed by various conventional clinical and echocardiographic parameters and global longitudinal and circumferential myocardial strain. Cut-off values to detect subclinical left ventricular dysfunction were established and applied in the hypertensive group. The Student's t test, Mann-Whitney test and chi-square test were used for the comparative statistical analysis.Results Most hypertensive subjects (53.7%) had grade I hypertension; blood pressure was controlled in 64.9%, and 54.8% showed left ventricular structural changes. Comparison between the normotensive and hypertensive groups showed no significant differences in parameters of global longitudinal or circumferential systolic strain. Application of the cut-offs to the hypertensive group identified 35 individuals (15.3%) as having subclinical left ventricular systolic dysfunction as assessed by global longitudinal myocardial strain parameters.Conclusions In this group of hypertensive patients, global myocardial strain parameters identified a group of individuals with subclinical left ventricular systolic dysfunction despite preserved ejection fraction. The clinical relevance of these findings needs to be assessed in long-term follow-up studies.  相似文献   
996.
《Journal of cardiology》2014,63(6):418-423
BackgroundThe aim of this study was to investigate the effect of a levosimendan infusion on hematological variables in patients with acute decompensated heart failure (ADHF). The predictive value of these variables for in-hospital mortality was also evaluated.MethodsA total of 553 patients (368 males; mean age, 63.4 ± 14.9 years) with acute exacerbations of advanced heart failure (ejection fraction ≤35%) and treated with either dobutamine or levosimendan were included in this retrospective analysis. The patients that received levosimendan therapy were divided into two groups according to in-hospital mortality: group 1 (21%) included patients who died during hospitalization (n = 45), while group 2 (79%) included patients with a favorable outcome (n = 174) after levosimendan infusion. Changes in several hematological variables between admission and the third day after levosimendan infusion were evaluated.ResultsThe demographic characteristics and risk factors of the two groups were similar. A comparison of changes in laboratory variables after the infusion of levosimendan revealed significant improvement only in those patients who had not died (group 2) during hospitalization. The neutrophil to lymphocyte (N/L) ratio after levosimendan infusion was an independent predictor of in-hospital mortality (odds ratio: 1.310, 95% CI: 1.158–1.483, p < 0.001). In a receiver-operating characteristic curve analysis, a value of 5.542 for the N/L ratio after levosimendan administration was identified as an effective cut-off point for predicting in-hospital mortality (area under the curve = 0.737; 95% confidence interval = 1100–1301; p < 0.001).ConclusionsLevosimendan treatment was associated with significant changes in hematological variables in patients with ADHF. A sustained higher N/L ratio after levosimendan infusion is associated with an increased risk of in-hospital mortality in patients with ADHF.  相似文献   
997.
Background and aimsThe triglyceride (TG)/high-density lipoprotein-cholesterol (HDL-C) ratio has been reported as a useful marker of atherogenic lipid abnormalities, insulin resistance, and cardiovascular disease. We evaluated in a large sample of children and adolescents the association of TG/HDL-C ratio with early signs of morphological vascular changes and cardiometabolic risk factors including nonalcoholic fatty liver disease (NAFLD).Methods and resultsThe study population, including 548 children (aged 6–16 years), of whom 157 were normal-weight, 118 overweight, and 273 obese, had anthropometric, laboratory, liver and carotid ultrasonography (carotid artery intima-media thickness-cIMT) data collected. Subjects were stratified into tertiles of TG/HDL-C. There was a progressive increase in body mass index (BMI), BMI-SD score (SDS), waist circumference, blood pressure (BP), liver enzymes, glucose, insulin, homeostasis model assessment of insulin resistance, high-sensitivity C-reactive protein (hsCRP), and cIMT values across TG/HDL-C tertiles. The odds ratios for central obesity, insulin resistance, high hsCRP, NAFLD, metabolic syndrome, and elevated cIMT increased significantly with the increasing tertile of TG/HDL-C ratio, after adjustment for age, gender, pubertal status, and BMI-SDS. In a stepwise multivariate logistic regression analysis, increased cIMT was associated with high TG/HDL-C ratio [OR, 1.81 (95% CI, 1.08–3.04); P < 0.05], elevated BP [5.13 (95% CI, 1.03–15.08); P < 0.05], insulin resistance [2.16 (95% CI, 1.30–3.39); P < 0.01], and NAFLD [2.70 (95% CI, 1.62–4.56); P < 0.01].ConclusionTG/HDL-C ratio may help identify children and adolescents at high risk for structural vascular changes and metabolic derangement.  相似文献   
998.
Background & aimsA Mediterranean-like dietary pattern has been shown to be inversely associated with many diseases, but its role in early obesity prevention is not clear. We aimed to determine if this pattern is common among European children and whether it is associated with overweight and obesity.Methods and resultsThe IDEFICS study recruited 16,220 children aged 2–9 years from study centers in eight European countries. Weight, height, waist circumference, and skinfolds were measured at baseline and in 9114 children of the original cohort after two years. Diet was evaluated by a parental questionnaire reporting children's usual consumption of 43 food items. Adherence to a Mediterranean-like diet was calculated by a food frequency-based Mediterranean Diet Score (fMDS).The highest fMDS levels were observed in Sweden, the lowest in Cyprus. High scores were inversely associated with overweight including obesity (OR = 0.85, 95% CI: 0.77; 0.94) and percent fat mass (β = −0.22, 95% CI: −0.43; −0.01) independently of age, sex, socioeconomic status, study center and physical activity. High fMDS at baseline protected against increases in BMI (OR = 0.87, 95% CI: 0.78; 0.98), waist circumference (OR = 0.87, 95% CI: 0.77; 0.98) and waist-to-height ratio (OR = 0.88, 95% CI: 0.78; 0.99) with a similar trend observed for percent fat mass (p = 0.06).ConclusionsAlthough a Mediterranean dietary pattern is inversely associated with childhood obesity, it is not common in children living in the Mediterranean region and should therefore be advocated as part of EU obesity prevention strategies.  相似文献   
999.
Background and aimsSimple, low-cost central obesity measures may help identify individuals with increased cardiometabolic disease risk, although it is unclear which measures perform best in African adults. We aimed to: 1) cross-sectionally compare the accuracy of existing waist-to-height ratio (WHtR) and waist circumference (WC) thresholds to identify individuals with hypertension, pre-diabetes, or dyslipidaemia; 2) identify optimal WC and WHtR thresholds to detect CVD risk in this African population; and 3) assess which measure best predicts 5-year CVD risk.Methods and resultsBlack South Africans (577 men, 942 women, aged >30years) were recruited by random household selection from four North West Province communities. Demographic and anthropometric measures were taken. Recommended diagnostic thresholds (WC > 80 cm for women, >94 cm for men; WHtR > 0.5) were evaluated to predict blood pressure, fasting blood glucose, lipids, and glycated haemoglobin measured at baseline and 5 year follow up. Women were significantly more overweight than men at baseline (mean body mass index (BMI) women 27.3 ± 7.4 kg/m2, men 20.9 ± 4.3 kg/m2); median WC women 81.9 cm (interquartile range 61–103), men 74.7 cm (63–87 cm), all P < 0.001). In women, both WC and WHtR significantly predicted all cardiometabolic risk factors after 5 years. In men, even after adjusting WC threshold based on ROC analysis, WHtR better predicted overall 5-year risk. Neither measure predicted hypertension in men.ConclusionsThe WHtR threshold of >0.5 appears to be more consistently supported and may provide a better predictor of future cardiometabolic risk in sub-Saharan Africa.  相似文献   
1000.
ABSTRACT

Compared with humans, who have more powerful auditory ability in discriminating and identifying speakers in noisy environments, traditional forensic automatic speaker recognizers do not perform well when dealing with noisy recordings. This paper proposes a GMM-UBM Forensic Automatic Speaker Recognition (FASR) System to reduce the effect of noise on performance. The system uses Gammatone Frequency Cepstral Coefficients (GFCC) based on an auditory periphery model and also incorporates a Principal Component Analysis (PCA) algorithm. The system was tested and validated using Mandarin voice databases compromised with different levels of white noise and office noise. The performance of the system was compared with a baseline system using Mel Frequency Cepstral Coefficients (MFCC) and also PCA under the same conditions. The results show that the performance of the combined GFCC system achieved a substantial improvement when compared with the baseline MFCC system under conditions of a high level of office noise.  相似文献   
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