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亚实性肺结节CT征象在良恶性鉴别及腺癌恶性侵袭程度评估中的价值 被引量:32
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作者 郭芳芳 李欣菱 +6 位作者 王欣悦 郑文松 王卿 宋文静 于铁链 范亚光 王颖 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第6期451-457,共7页
背景与目的亚实性肺结节为肺原发腺癌的常见计算机体层成像(computed tomography,CT)表现,依据其CT影像特征预测病理分型对确定临床治疗策略具有临床价值。本研究根据病理分类,回顾性分析良性、不典型腺瘤样增生(atypical adenomatous h... 背景与目的亚实性肺结节为肺原发腺癌的常见计算机体层成像(computed tomography,CT)表现,依据其CT影像特征预测病理分型对确定临床治疗策略具有临床价值。本研究根据病理分类,回顾性分析良性、不典型腺瘤样增生(atypical adenomatous hyperplasia,AAH)/原位腺癌(adenocarcinoma in situ,AIS)/微侵袭性腺癌(minimally invasive adenocarcinoma,MIA)、侵袭性腺癌三组亚实性肺结节的CT征象,评估其在良恶性鉴别及恶性侵袭程度判别中的价值。方法回顾性分析106例经手术切除亚实性结节的CT征象。依据手术病理分为良性和恶性组,恶性组根据侵袭程度分为无/微侵袭组(AAH/AIS/MIA)、侵袭性腺癌组,测量结节大小、实性成分比例、瘤肺界面、形状、边缘、胸膜牵拉征、空气支气管征、结节内血管异常等CT征象。根据单因素分析(χ2检验、非参数检验Mann-Whitney U检验)结果筛选有统计学差异的变量,纳入Logistic回归多因素分析。结果 Logistic回归分析显示清晰的瘤肺界面、空气支气管征以及结节内血管异常是恶性结节的重要预测指标,风险比分别为38.1(95%CI:5.0-287.7;P<0.01)、7.9(95%CI:1.3-49.3;P=0.03)、7.2(95%CI:1.4-37.0;P=0.02)。更大的实性成分所占比例是侵袭性腺癌与AAH/AIS/MIA组鉴别的重要指标,其风险比分别为1.04(95%CI:1.01-1.06,P=0.01)。结论亚实性结节中出现清晰的瘤肺界面、空气支气管征、结节内血管异常提示其恶性概率增加。恶性结节中实性成分所占比例越大预示着侵袭性更高。 展开更多
关键词 肺肿瘤 亚实性结节 计算机体层成像 定量变量 定性变量 良性 恶性
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基于深度学习的人工智能胸部CT肺结节检测效能评估 被引量:93
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作者 李欣菱 郭芳芳 +6 位作者 周振 张番栋 王卿 彭志君 苏大同 范亚光 王颖 《中国肺癌杂志》 CAS CSCD 北大核心 2019年第6期336-340,共5页
背景与目的肺结节精确检测是实现肺癌早诊的基础。基于深度学习的人工智能在肺内结节检测领域发展迅速,对其效能进行验证是促进其应用于临床的前提。本研究旨在评估基于深度学习技术的人工智能软件在胸部计算机断层扫描(computed tomogr... 背景与目的肺结节精确检测是实现肺癌早诊的基础。基于深度学习的人工智能在肺内结节检测领域发展迅速,对其效能进行验证是促进其应用于临床的前提。本研究旨在评估基于深度学习技术的人工智能软件在胸部计算机断层扫描(computed tomography, CT)恶性及非钙化结节检出中的价值。方法由天津医科大学总医院自建胸部CT肺结节数据库中随机抽取200例胸部CT数据,包含病理证实的肺癌及随访结节病例,导入肺结节人工智能识别系统,记录软件自动识别结节,并与原始影像报告结果进行对比。人工智能软件及阅片者检测到的结节由2名胸部专家进行评估并记录其大小及特征。计算灵敏度、假阳性率评估人工智能软件及医师的结节检测效能,应用McNemar检验确定二者之间是否存在显著性差异。结果 200例胸部多层螺旋CT共包含非钙化结节889枚,其中肺癌结节133枚,小于5 mm结节442枚。人工智能及放射科医师肺癌检出率皆为100%。人工智能软件结节检测灵敏度明显高于放射科医师(99.1%vs 43%, P<0.001)。人工智能总体假阳性率为每例CT 4.9个,排除5 mm以下结节后降为1.5个。结论基于深度学习的人工智能软件能实现恶性肺结节的无漏诊检出,具有较医师更高的结节检出灵敏度,在排除微小结节后可降低假阳性率。 展开更多
关键词 计算机体层成像 肺结节 深度学习 人工智能 检出
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Reasonable location of stopping line in close‑distance underlying coal seam and partition support of large cross‑section roadway 被引量:2
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作者 Dongdong Chen Yiyi Wu +3 位作者 Shengrong Xie fangfang guo Fulian He Ruipeng Liu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第4期181-202,共22页
Close-distance coal seams are widely distributed over China,and the coal pillars left by the overlying coal seams afect the retracement channel of the underlying coal seam in the stopping stage.Based on the engineerin... Close-distance coal seams are widely distributed over China,and the coal pillars left by the overlying coal seams afect the retracement channel of the underlying coal seam in the stopping stage.Based on the engineering background of close-distance seam mining in a coal mine,the reasonable position of the underlying coal seam's stopping line and the support method of the large section roadway during stopping are investigated using feld measurements,similar simulation experiments,and numerical simulations.There are three types of location relationships between the stopping line of the underlying coal seam and the stopping line of the overlying coal seam:"externally staggered with the upper stopping line"(ESUL,stops mining under the overlying goaf),"overlapped with upper stopping line"(OUL),and"internally staggered with the upper stopping line"(ISUL,ISUL-SD for shorter internal staggered distances,ISUL-LD for longer ones).There are diferent stress arch structures in the overlying strata of the above three positions,and the stress arch evolution process exists in the process of ESUL→OUL→ISUL-SD→ISUL-LD:a front and rear double stress arch structure→the front arch gradually decreases→the front arch dies out,and the double arch synthesizes the single arch→the single-arch range expands→the nested double arch.The relationship between the stress arch structure and the position of the stopping line is evaluated as follows:(1)ESUL:the stress concentration in the roof plate of the retracement channel of the underlying coal seam is the highest,because the overburden block of the extensive collapse zone acts directly on the roof plate of the retracement channel,resulting in relative difculties in roof support.(2)OUL:although the retracement channel roof pressure is minimal,the overlying rock structure has the potential for rotation or slippage instability.(3)ISUL-SD:the pressure on the roof of the retracement channel is small and the overburden structure is stable,which is conducive to the safe retraction of the support and not limited by the width of the end-mining coal pillar.(4)ISUL-LD:it is basically the same as the condition of stopping under the non-goaf;however,it has a limitation on the width of the end-mining coal pillar.The location of the stopping line is selected as ISUL-SD,and the retraction process of the self-excavating retraction channel was adopted.A partition asymmetric support scheme which is proven by feld practice is proposed,through a comprehensive analysis of the pre-stress feld simulation of the support scheme,based on the diferent control requirements of the roof above the support and the roof of the retracement channel in the stopping area.This method realizes safe and smooth withdrawal of the support. 展开更多
关键词 Close-distance coal seams Stopping line Stress arch structure Retracement channel Partition support
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PM_(2.5)中二次硫酸盐和硝酸盐生成机制 被引量:1
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作者 郭方方 谢绍东 《化学进展》 SCIE CAS CSCD 北大核心 2023年第9期1313-1326,共14页
二次无机硫酸盐和硝酸盐是PM_(2.5)的关键化学组分,对区域霾污染的形成有十分重要的作用。厘清两者的生成机制对于消除PM_(2.5)污染至关重要。二次硫酸盐和硝酸盐的生成机理十分复杂,包括气相、液相和非均相等多种反应。最近的实验和观... 二次无机硫酸盐和硝酸盐是PM_(2.5)的关键化学组分,对区域霾污染的形成有十分重要的作用。厘清两者的生成机制对于消除PM_(2.5)污染至关重要。二次硫酸盐和硝酸盐的生成机理十分复杂,包括气相、液相和非均相等多种反应。最近的实验和观测研究揭示了SO_(2)和NO_(2)生成硫酸盐和硝酸盐的新机理和详细的反应动力学,其被用于空气质量模型后可有效提升数值模式对硫酸盐和硝酸盐的时空分布特征及生成过程的模拟。本文系统总结了PM_(2.5)中二次硫酸盐和硝酸盐生成机制的最新进展,重点阐述了SO_(2)和NO_(2)氧化生成硫酸盐和硝酸盐的重要反应途径的机理和反应动力学结果,讨论了影响SO_(2)和NO_(2)氧化速率的因素以及在表征反应动力学时出现的重大实验挑战,同时探讨了硝酸盐对氮氧化物(NO_(x))、挥发性有机物(VOCs)、氨(NH_(3))减排的敏感性。最后,对未来研究发展方向提出了建议。 展开更多
关键词 硝酸盐 硫酸盐 生成机制 气溶胶液态水含量 气溶胶酸度
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Risk SNP-induced lncRNA-SLCCl drives colorectal cancer through activating glycolysis signaling 被引量:4
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作者 Tingting Yan Chaoqin Shen +14 位作者 Penglei Jiang Chenyang Yu fangfang guo Xianglong Tian Xiaoqiang Zhu Shiyuan Lu Bingshe Han Ming Zhong Jinxian Chen Qiang Liu Yingxuan Chen Junfang Zhang Jie Hong Haoyan Chen Jing-Yuan Fang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第3期962-974,共13页
Long non-coding RNAs(lncRNAs)play key roles in colorectal carcinogenesis.Here,we aimed to identify the risk SNP-induced lncRNAs and to investigate their roles in colorectal carcinogenesis.First,we identified rs6695584... Long non-coding RNAs(lncRNAs)play key roles in colorectal carcinogenesis.Here,we aimed to identify the risk SNP-induced lncRNAs and to investigate their roles in colorectal carcinogenesis.First,we identified rs6695584 as the causative SNP in 1 q41 locus.The A>G mutation of rs6695584 created a protein-binding motif of BATF,altered the enhancer activity,and subsequently activated IncSLCCl expression.Further validation in two independent CRC cohorts confirmed the upregulation of IncSLCCl in CRC tissues,and revealed that increased IncSLCCl expression was associated with poor survival in CRC patients.Mechanistically,lncRNA-SLCCl interacted with AHR and transcriptionally activated HK2 expression,the crucial enzyme in glucose metabolism,thereby driving the glycolysis pathway and accelerating CRC tumor growth.The functional assays revealed that IncSLCCl induced glycolysis activation and tumor growth in CRC mediated by HK2.In addition,HK2 was upregulated in colorectal cancer tissues and positively correlated with IncSLCCl expression and patient survival.Taken together,our findings reveal a risk SNP-mediated oncogene lncRNA-SLCCl promotes CRC through activating the glycolysis pathway. 展开更多
关键词 COLORECTAL GLYCOLYSIS METABOLISM
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Cu(I)-Catalyzed Asymmetric Cross-Coupling of N-Tosylhydrazones and Trialkyl- silylethynes: Enantioselective Construction of C(sp)--C(sp^3) Bonds 被引量:2
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作者 Wen-Dao Chu fangfang guo +5 位作者 Lefei Yu Junting Hong qianyi Liu Fanyang Mo Yan Zhang Jianbo Wang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2018年第3期217-222,共6页
The first catalytic enantioselective C(sp)-C(sp^3) cross-coupling reaction between N-tosylhydrazones and trialkylsilylethynes in the presence of Cu(I) salts and chiral phosphoramidite ligands was developed. A se... The first catalytic enantioselective C(sp)-C(sp^3) cross-coupling reaction between N-tosylhydrazones and trialkylsilylethynes in the presence of Cu(I) salts and chiral phosphoramidite ligands was developed. A series of svnthetically interesting, functionalized alkynes were obtained with moderate to good enanttiselectivities (up to 83% ee). Cu(ll) carbene migratory insertion is proposed to be the enantio-determining step. KEYWORDS C(sp)--C(sp^3) cross-coupling, metal carbene, asymmetric catalysis, Cu(I) catalysts, N-tosylhydrazones 展开更多
关键词 C(sp)--C(sp^3) cross-coupling metal carbene asymmetric catalysis Cu(I) catalysts N-tosylhydrazones
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人腺样体间充质干细胞向嗅感觉神经元诱导分化的体外研究
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作者 郭芳芳 余本铨 +4 位作者 陈勇 何郡 谷钰 万鑫 肖自安 《中华耳鼻咽喉头颈外科杂志》 CSCD 北大核心 2023年第3期233-239,共7页
目的探讨体外分离和培养人腺样体组织来源的间充质干细胞(adenoid-derived mesenchymal stem cells,aMSCs)的可行性,并诱导观察aMSCs向嗅感觉神经元的分化。方法收集2020年9—11月来源于中南大学湘雅二医院腺样体肥大患儿的手术切除腺... 目的探讨体外分离和培养人腺样体组织来源的间充质干细胞(adenoid-derived mesenchymal stem cells,aMSCs)的可行性,并诱导观察aMSCs向嗅感觉神经元的分化。方法收集2020年9—11月来源于中南大学湘雅二医院腺样体肥大患儿的手术切除腺样体组织,胰蛋白酶消化联合贴壁法培养P0细胞,传代培养,流式细胞技术检测P5代细胞表面抗原CD45、CD73、CD90的表达,观察成骨、成脂诱导分化能力。采用维甲酸(retinoic acid,RA)、音猬因子(sonic hedgehog,SHH)、碱性成纤维生长因子(basic fibroblast growth factor,bFGF),以及RA+SHH、RA+bFGF、SHH+bFGF和RA+SHH+bFGF分别诱导分化P5代aMSCs,倒置显微镜下观察细胞形态,免疫荧光抗体法检测细胞表面感觉神经元标志物β-tubulin 3、嗅感觉神经元标志物生长相关蛋白-43(growth associated protein-43,GAP43)和嗅标记蛋白(olfactory maker protein,OMP)的表达。采用两个样本率的四格表资料的χ2检验比较表达强度的差异。结果P0代aMSCs具有良好的贴壁和增殖性能,P2代细胞已基本纯化。P5代细胞阳性表达CD73和CD90,其纯度分别为99.3%和97.75%,不表达CD45,成骨和成脂诱导分化良好。RA、SHH、bFGF诱导分化细胞均成神经元样外观,β-tubulin 3阳性表达;bFGF+SHH组和RA+SHH+bFGF组诱导细胞均表达GAP43,后组表达阳性更强(χ^(2)=17.48,P<0.005);所有诱导组均未见OMP阳性表达。结论腺样体组织可培养获得能稳定传代、具有良好分化能力的aMSCs。aMSCs是间充质干细胞家族新成员,具有向神经元分化的能力,RA、SHH和bFGF体外联合诱导能促使其分化为未成熟嗅感觉神经元。 展开更多
关键词 腺样体 间充质干细胞 体外诱导 嗅感觉神经元
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NONLINEAR LAGRANGIANS FOR NONLINEAR PROGRAMMING BASED ON MODIFIED FISCHER-BURMEISTER NCP FUNCTIONS
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作者 Yonghong Ren fangfang guo Yang Li 《Journal of Computational Mathematics》 SCIE CSCD 2015年第4期396-414,共19页
This paper proposes nonlinear Lagrangians based on modified Fischer-Burmeister NCP functions for solving nonlinear programming problems with inequality constraints. The convergence theorem shows that the sequence of p... This paper proposes nonlinear Lagrangians based on modified Fischer-Burmeister NCP functions for solving nonlinear programming problems with inequality constraints. The convergence theorem shows that the sequence of points generated by this nonlinear La- grange algorithm is locally convergent when the penalty parameter is less than a threshold under a set of suitable conditions on problem functions, and the error bound of solution, depending on the penalty parameter, is also established. It is shown that the condition number of the nonlinear Lagrangian Hessian at the optimal solution is proportional to the controlling penalty parameter. Moreover, the paper develops the dual algorithm associ- ated with the proposed nonlinear Lagrangians. Numerical results reported suggest that the dual algorithm based on proposed nonlinear Lagrangians is effective for solving some nonlinear optimization problems. 展开更多
关键词 nonlinear Lagrangian nonlinear Programming modified Fischer-BurmeisterNCP function dual algorithm condition number
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Convergence analysis of an infeasible quasi- Newton bundle method for nonsmooth convex programming
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作者 Jie SHEN fangfang guo Liping PANG 《Frontiers of Mathematics in China》 CSCD 2023年第5期367-380,共14页
By utilizing the improvement function,we change the nonsmooth convex constrained optimization into an unconstrained optimization,and construct an infeasible quasi-Newton bundle method with proximal form.It should be n... By utilizing the improvement function,we change the nonsmooth convex constrained optimization into an unconstrained optimization,and construct an infeasible quasi-Newton bundle method with proximal form.It should be noted that the objective function being minimized in unconstrained optimization subproblem may vary along the iterations(it does not change if the null step is made,otherwise it is updated to a new function).It is necessary to make some adjustment in order to obtain the convergence result.We employ the main idea of infeasible bundle method of Sagastizabal and Solodov,and under the circumstances that each iteration point may be infeasible for primal problem,we prove that each cluster point of the sequence generated by the proposed algorithm is the optimal solution to the original problem.Furthermore,for BFGS quasi-Newton algorithm with strong convex objective function,we obtain the condition which guarantees the boundedness of quasi-Newton matrices and the R-linear convergence of the iteration points. 展开更多
关键词 Non-smooth optimization convex constraint improvement function bundle method quasi-Newton direction
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