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1.
目的研究腰椎间盘突出症组织不同程度自然吸收与腰椎曲度的相关性。方法回顾分析上海市宝山区仁和医院2015年1月至2019年6月CT检查确诊腰椎间盘突出症病人61例,均为保守治疗,并具有6~24个月随访复查资料。根据突出物自然吸收程度分为明显重吸收组(10例),部分重吸收组(8例),基本不变组(30例),增大组(13例)四组,配对比较每组腰椎曲线指数、腰椎前凸角变化,并进行相关分析。结果腰椎间盘突出症明显重吸收组、部分重吸收组、基本不变组、增大组的首次CT检查腰椎曲线指数、腰椎前凸角比较,差异无统计学意义(P>0.05);经治疗后随访CT腰椎曲线指数[10.65(9.23,13.31)mm 比11.69(8.31,15.25)mm 比8.63(6.75,11.00)mm 比8.06(5.00,10.05)mm]、腰椎前凸角[46.30(43.96,48.18)°比45.36(44.15,47.67)°比39.37(32.27,45.74)°比35.39(29.60,43.16)°]比较,差异有统计学意义(P<0.05)。明显吸收组、部分重吸收组随访腰椎曲线指数、腰椎前凸角较首次CT检查增大(P<0.05);增大组随访腰椎曲线指数、腰椎前凸角较首次CT检查减小(P<0.05);基本不变组腰椎曲线指数、腰椎前凸角前后配对比较差异无统计学意义(P>0.05)。腰椎间盘突出症自然吸收程度与腰椎曲线指数、腰椎前凸角变化均呈正相关(rs=0.50、0.47,P<0.05)。结论腰椎曲线指数及腰椎前凸角随着腰椎突出椎间盘自然吸收而增大,当腰椎突出椎间盘增大时腰椎曲线指数及腰椎前凸角也相应减小。腰椎间盘突出症组织自然吸收程度与腰椎曲度变化呈正相关。  相似文献   
2.
We propose a Deep learning-based weak label learning method for analyzing whole slide images (WSIs) of Hematoxylin and Eosin (H&E) stained tumor tissue not requiring pixel-level or tile-level annotations using Self-supervised pre-training and heterogeneity-aware deep Multiple Instance LEarning (DeepSMILE). We apply DeepSMILE to the task of Homologous recombination deficiency (HRD) and microsatellite instability (MSI) prediction. We utilize contrastive self-supervised learning to pre-train a feature extractor on histopathology tiles of cancer tissue. Additionally, we use variability-aware deep multiple instance learning to learn the tile feature aggregation function while modeling tumor heterogeneity. For MSI prediction in a tumor-annotated and color normalized subset of TCGA-CRC (n=360 patients), contrastive self-supervised learning improves the tile supervision baseline from 0.77 to 0.87 AUROC, on par with our proposed DeepSMILE method. On TCGA-BC (n=1041 patients) without any manual annotations, DeepSMILE improves HRD classification performance from 0.77 to 0.81 AUROC compared to tile supervision with either a self-supervised or ImageNet pre-trained feature extractor. Our proposed methods reach the baseline performance using only 40% of the labeled data on both datasets. These improvements suggest we can use standard self-supervised learning techniques combined with multiple instance learning in the histopathology domain to improve genomic label classification performance with fewer labeled data.  相似文献   
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4.

Background

While drinking alcohol, one must choose between the immediate rewarding effects and the delayed reward of a healthier lifestyle. Individuals differ in their devaluation of a delayed reward based on the time required to receive it, i.e., delay discounting (DD). Previous studies have shown that adolescents discount more steeply than adults and that steeper DD is associated with heavier alcohol use in both groups.

Methods

In a large-scale longitudinal study, we investigated whether higher rates of DD are an antecedent or a consequence of alcohol use during adolescent development. As part of the IMAGEN project, 2220 adolescents completed the Monetary Choice Questionnaire as a DD measure, the Alcohol Use Disorders Identification Test, and the Timeline Follow Back interview at ages 14, 16, 18, and 22. Bivariate latent growth curve models were applied to investigate the relationship between DD and drinking. To explore the consequences of drinking, we computed the cumulative alcohol consumption and correlated it with the development of discounting. A subsample of 221 participants completed an intertemporal choice task (iTeCh) during functional magnetic resonance imaging at ages 14, 16, and 18. Repeated-measures ANOVA was used to differentiate between high-risk and low-risk drinkers on the development of neural processing during intertemporal choices.

Results

Overall, high rates of DD at age 14 predicted a greater increase in drinking over 8 years. In contrast, on average, moderate alcohol use did not affect DD from ages 14 to 22. Of note, we found indicators for less brain activity in top-down control areas during intertemporal choices in the participants who drank more.

Conclusions

Steep DD was shown to be a predictor rather than a consequence of alcohol use in low-level drinking adolescents. Important considerations for future longitudinal studies are the sampling strategies to be used and the reliability of the assessments.
  相似文献   
5.
BackgroundInflammation surrounding the coronary arteries can be non-invasively assessed using pericoronary adipose tissue attenuation (PCAT). While PCAT holds promise for further risk stratification of patients with low coronary artery disease (CAD) prevalence, its value in higher risk populations remains unknown.MethodsCORE320 enrolled patients referred for invasive coronary angiography with known or suspected CAD. Coronary computed tomography angiography (CCTA) images were collected for 381 patients for whom clinical outcomes were assessed 5 years after enrollment. Using semi-automated image analysis software, PCAT was obtained and normalized for the right coronary (RCA), left anterior descending (LAD), and left circumflex arteries (LCx). The association between PCAT and major adverse cardiovascular events (MACE) during follow up was assessed using Cox regression models.ResultsThirty-seven patients were excluded due to technical failure. For the remaining 344 patients, median age was 62 (interquartile range, 55–68) with 59% having ≥1 coronary artery stenosis of ≥50% by quantitative coronary angiography. Mean attenuation values for PCAT in RCA, LAD, and LCx were ?74.9, ?74.2, and ?71.2, respectively. Hazard ratios and 95% confidence intervals (CI) for normalized PCAT in the RCA, LAD, and LCx for MACE were 0.96 (CI: 0.75–1.22, p ?= ?0.71), 1.31 (95% CI: 0.96–1.78, p ?= ?0.09), and 0.98 (95% CI: 0.78–1.22, p ?= ?0.84), respectively. For death, stroke, or myocardial infarction only, hazard ratios were 0.68 (0.44–1.07), 0.85 (0.56–1.29), and 0.57 (0.41–0.80), respectively.ConclusionsIn patients referred for invasive coronary angiography with suspected CAD, PCAT did not predict MACE during long term follow up. Further studies are needed to understand the relationship of PCAT with CAD risk.  相似文献   
6.
Mass characteristic frequency (fmass) is a novel shear wave (SW) parameter that represents the ratio of the averaged minimum SW speed within the regions of interest to the largest dimension of the mass. Our study objective was to evaluate if the addition of fmass to conventional 2-D shear wave elastography (SWE) parameters would improve the differentiation of benign from malignant thyroid nodules. Our cohort comprised 107 patients with 113 thyroid nodules, of which 67 (59%) were malignant. Two-dimensional SWE data were obtained using the Supersonic Imagine Aixplorer ultrasound system equipped with a 44- to 15-MHz15-MHz linear array transducer. A receiver operating characteristic curve was generated based on a multivariable logistic regression analysis to evaluate the ability of SWE parameters with/without fmass and with/without clinical factors to discriminate benign from malignant thyroid nodules. The addition of fmass to conventional SW elasticity parameters increased the area under the curve from 0.808 to 0.871 (p = 0.02). The combination of SW elasticity parameters plus fmass plus clinical factors provided the strongest thyroid nodule malignancy probability estimate, with a sensitivity of 93.4% and specificity of 91.1% at the optimal threshold. In summary, fmass can be a valuable addition to conventional 2-D SWE parameters.  相似文献   
7.
目的:分析急性草甘膦中毒患者预后的影响因素,以期为急性草甘膦的预防和治疗提供参考依据。方法:本研究回顾性选取我院2009年9月—2021年2月期间收治的73例急性草甘膦中毒患者的临床资料,其中男32例,女41例;平均年龄(55.86±17.60)岁;所有患者均随访6个月。随访终点事件为全因死亡,全因死亡12例(16.4%)。按照临床结局分为存活组和死亡组,比较2组患者临床特征及实验室指标差异,将单因素分析中差异具有统计学意义的指标纳入多元logistic回归分析,得出独立预后影响因素,使用受试者工作特征(ROC)曲线检验独立危险因素在急性草甘膦中毒预后的预测价值。结果:73例患者单因素分析显示,死亡组年龄、首次医疗接触(FMC)、总胆红素(TBIL)、谷氨酰转移酶(GGT)、碱性磷酸酶(ALP)、谷草转氨酶(AST)、氯、白细胞、凝血时间均大于存活组,钾低于存活组(P<0.05);多元logistic回归分析显示,GGT、白细胞、凝血时间、年龄及接触医疗时间为急性草甘膦中毒患者预后的影响因素(P<0.05);创建新的预测模型:-21.559+0.054×GGT(U/L)+0.253×白细胞(×109/L)+0.593×凝血时间(s)+0.103×年龄(岁)(>70岁=1,<70岁=0)+1.656×FMC(2 h以内=1、2~6 h=2、6 h以上=3);ROC曲线显示,预测模型的AUC为0.900,临界值为0.622,此时的敏感度为91.7%,特异度为70.5%,诊断价值优于单一指标。结论:GGT、白细胞、凝血时间、年龄及接触医疗时间是预测急性草甘膦中毒患者预后的独立危险因素,建立新的预测模型对急性草甘膦中毒患者预后具有较好的预测价值。  相似文献   
8.
9.
目的:通过实时荧光PCR-高分辨熔解曲线(HRM)联合分析技术,建立小活络丸(大蜜丸)中小麦粉掺伪快速、准确鉴别方法。方法:通过优化前处理方法,提取小活络丸样品的基因组;通过文献检索和生物信息学分析,得到小麦粉特异性引物;使用实时荧光PCR-HRM技术,对10批次小麦(粉)、16种其他禾本科植物及7种常见高淀粉食物样品进行特异性扩增,采用克隆测序对结果进行再确认;考察实时荧光PCR-HRM方法的检出限、精密度和重复性,同时对市售的小活络丸样品进行检测。结果:试验筛选获得了适用于本研究的特异性引物,建立了实时荧光PCR-HRM小活络丸掺伪小麦的检测方法;小活络丸样品掺伪小麦粉的检出限为0.01 g·g-1,试验精密度Ct值为26.63(RSD=2.15%),Tm值为89.53℃(RSD=0.05%);重复性Ct值为26.65(RSD=3.20%),Tm值为89.53℃(RSD=0.12%)。试验对市售的4个厂家9批次共计81份样品进行分析,确定了3批次来源于A厂家的小活络丸样品存在小麦粉掺伪的问题,将PCR扩增产物克隆测序,其结果为小麦(Triticum Aestivum L.)。结论:本研究建立了实时荧光PCR-HRM检测方法,可以快速判定小活络丸中小麦粉掺伪样品。  相似文献   
10.
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