目的:研究基于动脉对比增强磁共振成像(DCE-MRI)影像组学和常规MRI特征的列线图用于术前预测浸润性乳腺癌(IBC)患者的淋巴血管侵犯(LVI)状态。方法:回顾性分析2016年7月至2021年5月间,经术后病理证实的300例IBC患者,并按照8:2比例随机...目的:研究基于动脉对比增强磁共振成像(DCE-MRI)影像组学和常规MRI特征的列线图用于术前预测浸润性乳腺癌(IBC)患者的淋巴血管侵犯(LVI)状态。方法:回顾性分析2016年7月至2021年5月间,经术后病理证实的300例IBC患者,并按照8:2比例随机分为训练组(n=238)和验证组(n=62)。对所有患者第二期DCE-MRI图像中的病灶区进行手动分割,并提取影像组学特征。采用方差阈值、select k best、LASSO回归进行影像组学特征筛选并计算影像组学评分(rad-score)。使用Logistic回归分析筛选常规MRI特征建立常规特征模型,并结合影像组学和常规MRI特征中的独立危险因素构建联合预测模型,并绘制列线图。使用受试者工作特征(ROC)曲线和校准曲线评估模型的效能,使用决策曲线分析评估模型的临床价值。结果:共提取到1 409个影像组学特征,经筛选得到15个影像组学特征与乳腺癌LVI状态相关,参与计算rad-score值。所有常规MRI特征中,最大直径(OR=1.743,P<0.001)和毛刺征(OR=6.304,P<0.001)是预测LVI阳性的独立危险因素。在训练组及验证组中,影像组学模型的ROC曲线下面积(AUC)分别为0.831和0.811;常规特征模型的AUC分别为0.779和0.770;联合预测模型的AUC分别可提高到0.889(95%CI=0.844~0.934)和0.856(95%CI=0.759~0.952)。校准曲线表明列线图预测值和实际值吻合较好,决策曲线显示列线图有较高的临床应用价值。结论:基于DCE-MRI影像组学和常规MRI特征构建的列线图用于术前预测IBC患者LVI状态具有良好的应用价值,可为临床治疗提供参考。展开更多
Bimetallic Au/Pd nanoparticles were prepared and used to catalyze oxidation of alcohols in the poly(ethylene glycol) (PEG)/CO_(2) biphasic system using O2 as the oxidant without adding any base.The catalytic activity ...Bimetallic Au/Pd nanoparticles were prepared and used to catalyze oxidation of alcohols in the poly(ethylene glycol) (PEG)/CO_(2) biphasic system using O2 as the oxidant without adding any base.The catalytic activity of Au/Pd bimetal with different mole ratios was studied using benzyl alcohol as the substrate.It was found that bimetallic Au/Pd nanoparticles with Au:Pd=1:3.5 had higher catalytic activity than monometallic Au,Pd and the bimetallic Au/Pd nanoparticles with other molar ratios.The effect of CO_(2) pressure on the oxidation of benzyl alcohol and 1-phenylethanol in PEG/CO_(2) was investigated.It was demonstrated that CO_(2) pressure could be used to tune the conversion and selectivity of the reactions effectively.α,β-Unsaturated alcohols were also studied and found to be more reactive than benzyl alcohol and 1-phenylethanol.Recycling experiments showed that the Au/Pd/PEG/CO_(2) catalytic system could be recycled at least four times without reducing the activity.In addition,the catalytic system is clean and the products can be separated easily.展开更多
文摘目的:研究基于动脉对比增强磁共振成像(DCE-MRI)影像组学和常规MRI特征的列线图用于术前预测浸润性乳腺癌(IBC)患者的淋巴血管侵犯(LVI)状态。方法:回顾性分析2016年7月至2021年5月间,经术后病理证实的300例IBC患者,并按照8:2比例随机分为训练组(n=238)和验证组(n=62)。对所有患者第二期DCE-MRI图像中的病灶区进行手动分割,并提取影像组学特征。采用方差阈值、select k best、LASSO回归进行影像组学特征筛选并计算影像组学评分(rad-score)。使用Logistic回归分析筛选常规MRI特征建立常规特征模型,并结合影像组学和常规MRI特征中的独立危险因素构建联合预测模型,并绘制列线图。使用受试者工作特征(ROC)曲线和校准曲线评估模型的效能,使用决策曲线分析评估模型的临床价值。结果:共提取到1 409个影像组学特征,经筛选得到15个影像组学特征与乳腺癌LVI状态相关,参与计算rad-score值。所有常规MRI特征中,最大直径(OR=1.743,P<0.001)和毛刺征(OR=6.304,P<0.001)是预测LVI阳性的独立危险因素。在训练组及验证组中,影像组学模型的ROC曲线下面积(AUC)分别为0.831和0.811;常规特征模型的AUC分别为0.779和0.770;联合预测模型的AUC分别可提高到0.889(95%CI=0.844~0.934)和0.856(95%CI=0.759~0.952)。校准曲线表明列线图预测值和实际值吻合较好,决策曲线显示列线图有较高的临床应用价值。结论:基于DCE-MRI影像组学和常规MRI特征构建的列线图用于术前预测IBC患者LVI状态具有良好的应用价值,可为临床治疗提供参考。
基金the National Natural Science Foundation of China (20973177 & 20932002)Ministry of Science and Technology of China (2006CB202504)Chinese Academy of Sciences (KJCX2. YW.H16) for financial supports
文摘Bimetallic Au/Pd nanoparticles were prepared and used to catalyze oxidation of alcohols in the poly(ethylene glycol) (PEG)/CO_(2) biphasic system using O2 as the oxidant without adding any base.The catalytic activity of Au/Pd bimetal with different mole ratios was studied using benzyl alcohol as the substrate.It was found that bimetallic Au/Pd nanoparticles with Au:Pd=1:3.5 had higher catalytic activity than monometallic Au,Pd and the bimetallic Au/Pd nanoparticles with other molar ratios.The effect of CO_(2) pressure on the oxidation of benzyl alcohol and 1-phenylethanol in PEG/CO_(2) was investigated.It was demonstrated that CO_(2) pressure could be used to tune the conversion and selectivity of the reactions effectively.α,β-Unsaturated alcohols were also studied and found to be more reactive than benzyl alcohol and 1-phenylethanol.Recycling experiments showed that the Au/Pd/PEG/CO_(2) catalytic system could be recycled at least four times without reducing the activity.In addition,the catalytic system is clean and the products can be separated easily.