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磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值 被引量:1
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作者 唐毅 张辉 +1 位作者 黄恺 黎本丰 《中国CT和MRI杂志》 2024年第4期163-165,共3页
目的探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。方法选取2020年1月至2022年11月在我院治疗的110例膝关节早期软骨退变患者(观察组),按照疾病严重程度分为轻度退变组及重度退变组,另选取同期在我... 目的探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。方法选取2020年1月至2022年11月在我院治疗的110例膝关节早期软骨退变患者(观察组),按照疾病严重程度分为轻度退变组及重度退变组,另选取同期在我院进行体检的64例健康者为对照组,受试者均行磁共振T1rho序列、T2 mapping技术扫描,测量受试者T2值及T1ρ值,探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。结果观察组股骨外侧面、股骨内侧面、胫骨外侧面、胫骨内侧面、髋骨面T2值均明显高于对照组(P<0.05),重度退变亚组患者股骨外侧面、股骨内侧面、胫骨外侧面、胫骨内侧面、髋骨面T2值显著高于轻度退变者(P<0.05);观察组股骨内踝负重区、股骨内踝非负重区、股骨外踝负重区、股骨外踝非负重区、胫骨外侧平台区、胫骨内侧平台区、髌后软骨区磁共振T1ρ值明显高于对照组(P<0.05),重度退变亚组患者股骨内踝负重区、股骨内踝非负重区、股骨外踝负重区、股骨外踝非负重区、胫骨外侧平台区、胫骨内侧平台区、髌后软骨区磁共振T1ρ值明显高于轻度退变亚组患者(P<0.05);磁共振T1rho序列在膝关节早期软骨退变中早期诊断及严重程度评估中的的诊断ROC值及特异度明显高于T2 mapping技术(P<0.05),但后者具有更高的敏感度(P<0.05)。结论磁共振T1rho序列、T2 mapping技术均能有效反映膝关节早期软骨退变中软骨组织学成分变化情况,还可为膝关节软骨退变严重程度评估提供客观依据,二者具有一定互补价值。 展开更多
关键词 磁共振T1rho序列 T2 mapping技术 膝关节 早期软骨退变 诊断
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ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR
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作者 陈洁玲 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期295-310,共16页
In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,... In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open harmonic.Finally,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors. 展开更多
关键词 Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping UNIVALENT
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DWI联合T2 mapping序列鉴别前列腺癌与前列腺增生价值评估 被引量:2
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作者 李茜玮 陈丽华 +2 位作者 王楠 林良杰 刘爱连 《磁共振成像》 CAS CSCD 北大核心 2024年第2期97-102,共6页
目的探讨扩散加权成像(diffusion-weighted imaging,DWI)联合T2 mapping序列鉴别前列腺癌(prostate cancer,PCa)与前列腺增生(benign prostatic hyperplasia,BPH)的价值。材料与方法回顾性分析本院行3.0 T MRI检查且经病理证实的56例PC... 目的探讨扩散加权成像(diffusion-weighted imaging,DWI)联合T2 mapping序列鉴别前列腺癌(prostate cancer,PCa)与前列腺增生(benign prostatic hyperplasia,BPH)的价值。材料与方法回顾性分析本院行3.0 T MRI检查且经病理证实的56例PCa患者及40例BPH患者资料。扫描序列包括T1WI、T2WI、DWI及T2 mapping序列。两名观察者分别测量两组病灶的表观扩散系数(apparent diffusion coefficient,ADC)值及T2值。采用组内相关系数(intra-class correlation coefficient,ICC)评估两名观察者测得参数值的一致性。采用独立样本t检验或Mann-Whitney U检验分析两组病例间ADC值及T2值的差异。Logistic回归用于分析差异具有统计学意义的参数及其与基线资料联合的诊断模型。采用受试者工作特征(receiver operating characteristic,ROC)曲线评估有差异参数及联合模型的诊断效能。采用DeLong检验比较ROC曲线下面积差异。采用Spearman相关系数分析ADC值与T2值相关性。结果两名观察者测量值一致性好(ICC>0.75)。PCa组的ADC值及T2值分别低于BPH组,差异具有统计学意义(P<0.01)。ADC值、T2值、ADC-T2及ADC-T2-年龄-总前列腺特异性抗原(total prostate specific antigen,TPSA)联合鉴别PCa与BPH的AUC值分别为0.843、0.830、0.896及0.927。DeLong检验显示ADC值与ADC-T2联合,ADC值、T2值、ADC-T2模型与ADC-T2-年龄-TPSA联合模型的ROC差异存在统计学意义(P<0.05)。ADC值与T2值呈正相关(r=0.331,P<0.01)。结论DWI及T2 mapping序列在鉴别PCa与BPH方面具有较好的价值,并且两序列联合临床指标时诊断效能提升,可为临床无创诊断PCa及BPH提供很好的指导意义。 展开更多
关键词 前列腺癌 前列腺增生 扩散加权成像 T2 mapping成像 磁共振成像 鉴别诊断
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T1 mapping技术及在评估心肌纤维化中的应用进展
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作者 李丹丹 王倩 +1 位作者 徐晶 张维升 《中国医学影像学杂志》 CSCD 北大核心 2024年第9期966-971,共6页
T1 mapping技术是近年来应用较为广泛的MRI新技术,其通过量化心肌组织的T1值和细胞外容积分数,可对导致心肌纤维化的疾病进行评估。本文综述T1 mapping的基本原理、扫描序列及在导致心肌纤维化的疾病中的应用,主要包括心梗、肥厚型心肌... T1 mapping技术是近年来应用较为广泛的MRI新技术,其通过量化心肌组织的T1值和细胞外容积分数,可对导致心肌纤维化的疾病进行评估。本文综述T1 mapping的基本原理、扫描序列及在导致心肌纤维化的疾病中的应用,主要包括心梗、肥厚型心肌病、扩张型心肌病、先天性心脏病、主动脉狭窄、高血压性心脏病、糖尿病心肌病、尿毒症性心肌病、射血分数保留型心衰、心脏移植等。 展开更多
关键词 磁共振成像 T1 mapping 心肌疾病 细胞外容积分数 综述
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MR弹性成像与钆塞酸二钠增强T1 mapping定量评估兔肝纤维化的对比研究
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作者 张豪 邹立秋 +2 位作者 钟文新 麦晓飞 石桥 《磁共振成像》 CAS CSCD 北大核心 2024年第8期172-178,共7页
目的评价MR弹性成像(magnetic resonance elastography,MRE)、钆塞酸二钠(gadolinium ethoxybenzyl diethyle netriamine pentaacetic acid,Gd-EOB-DTPA)增强T1 mapping在肝纤维化(liver fibrosis,LF)早期定量的价值。材料与方法实验材... 目的评价MR弹性成像(magnetic resonance elastography,MRE)、钆塞酸二钠(gadolinium ethoxybenzyl diethyle netriamine pentaacetic acid,Gd-EOB-DTPA)增强T1 mapping在肝纤维化(liver fibrosis,LF)早期定量的价值。材料与方法实验材料为新西兰大白兔(共120只),分为正常对照组(n=20)与肝纤维化组[LF组,50%四氯化碳(carbon tetrachloride,CCL_(4))油溶液模型,n=100],分别在第4、5、6、15周末取5只对照组与25只LF组兔行MRI肝脏轴位T1WI、MRE及Gd-EOB-DTPA增强T1 mapping扫描,测量肝脏弹性硬度(liver stiffness,LS)、平扫T1弛豫时间(T1_(native))及Gd-EOB-DTPA增强T1 mapping扫描20 min后T1弛豫时间(T1_(20min)),计算T1弛豫时间减少率(ΔT1_(20min))及1/T1弛豫时间增加值(ΔR1_(20min));采用Scheuer评分系统进行LF病理学分期,单因素方差分析对比各定量参数与LF分期间的差异,Spearman相关性分析比较各定量参数与LF病理分期相关性,受试者工作特征(receiver operating characteristic,ROC)曲线评估各定量参数对LF分期诊断效能。结果共纳入96只活兔模型,病理学评分:F0期15只、F1期22只、F2期22只、F3期18只、F4期19只。LS、T1_(native)、T1_(20min)、ΔT1_(20min)、ΔR1_(20min)于LF各期间差异均有统计学意义(P<0.05)。LS、T1_(native)、T1_(20min)、ΔT1_(20min)、ΔR1_(20min)均与LF分期相关(r=0.935、0.559、0.770、-0.418、-0.686,P<0.001)。F0 vs.F1~F4、F0 vs.F1~F2、F0 vs.F3~F4、F1~F2 vs.F3~F4的LS值ROC曲线下面积(area under the curve,AUC)分别为0.988、0.979、1.000、0.995,T1_(20min)值AUC分别为0.914、0.852、0.987、0.896。结论在评估LF早期诊断中,MRE及Gd-EOB-DTPA增强T1 mapping成像均显示出较好的诊断价值,MRE优于Gd-EOB-DTPA增强T1 mapping。 展开更多
关键词 肝纤维化 磁共振弹性成像 肝脏硬度 钆塞酸二钠 T1 mapping成像
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T1 mapping技术用于评估心尖肥厚型心肌病患者心肌钆沉积 被引量:1
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作者 杨宏志 兰天 杨如武 《中国医学影像技术》 CSCD 北大核心 2024年第2期226-230,共5页
目的观察T1 mapping技术用于评估心尖肥厚型心肌病(AHCM)患者心肌钆沉积的可行性。方法回顾性分析60例AHCM患者资料,根据是否接受含钆对比剂(GBCA)注射分为增强组和对照组各30例;基于2组心脏T1 mapping测量左心室基底部、中间部、心尖... 目的观察T1 mapping技术用于评估心尖肥厚型心肌病(AHCM)患者心肌钆沉积的可行性。方法回顾性分析60例AHCM患者资料,根据是否接受含钆对比剂(GBCA)注射分为增强组和对照组各30例;基于2组心脏T1 mapping测量左心室基底部、中间部、心尖部心肌T1值及相应层面脾脏T1值,计算T1相对值(T1R),比较组间及增强组内左心室不同部位心肌T1R,并对增强组T1R基于性别、年龄、体质量指数、心功能、高血压、高血脂、糖尿病、心尖厚度、射血分数、延迟强化、首次增强检查至末次复查间隔时间及GBCA总量进行进一步分析。结果组间T1R_(基底部)、T1R_(中间部)、T1R_(心尖部)差异均无统计学意义(t=0.329、1.484、0.720,P均>0.05)。增强组内,左心室不同部位心肌T1R差异无统计学意义(F=0.765,P>0.05),不同性别及有无高血压患者间心肌T1R差异均有统计学意义(P均<0.05)。结论T1 mapping技术可用于评估AHCM患者心肌钆沉积。 展开更多
关键词 心肌病 肥厚型 T1 mapping 心肌钆沉积
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基于T1 mapping技术的定量参数评估肝细胞肝癌微血管侵犯的研究
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作者 韦孟 冯秋霞 刘希胜 《现代肿瘤医学》 CAS 2024年第11期2059-2064,共6页
目的:探讨基于T1 mapping技术的定量参数在预测肝细胞肝癌(hepatocellular carcinoma,HCC)微血管侵犯(microvascular invasion,MVI)的价值。方法:回顾性分析34例接受肝脏特异性对比剂钆塞酸二钠(Gd-EOB-DTPA)增强MRI检查且术后病理及免... 目的:探讨基于T1 mapping技术的定量参数在预测肝细胞肝癌(hepatocellular carcinoma,HCC)微血管侵犯(microvascular invasion,MVI)的价值。方法:回顾性分析34例接受肝脏特异性对比剂钆塞酸二钠(Gd-EOB-DTPA)增强MRI检查且术后病理及免疫组化证实为HCC患者的临床及磁共振影像资料,根据MVI状态分为MVI阳性组(21例)及MVI阴性组(13例)。所有患者均行平扫期及平衡期的T1 mapping成像,测量肿瘤实质部分、肿瘤整体、瘤周1 cm以及正常肝实质背景的T1弛豫时间,结合红细胞压积水平,计算肿瘤实质及肿瘤整体的细胞外容积分数(ECV)。比较MVI两组之间各T1弛豫时间及ECV定量参数之间的差异,采用受试者工作特征(receiver operating characteristic,ROC)曲线评价各变量的诊断效能,并计算截断值、敏感度、特异度及曲线下面积(area under curve,AUC)。结果:MVI阳性组与MVI阴性组间在瘤周1 cm增强前T1弛豫时间、肿瘤实质ECV和肿瘤整体ECV上差异有统计学意义(P<0.05),AUC分别为0.707(95%CI:0.509~0.905)、0.780(95%CI:0.593~0.967)和0.736(95%CI:0.5469~0.9256)。结论:基于T1 mapping技术的瘤周1 cm增强前T1弛豫时间、肿瘤实质ECV及肿瘤整体ECV均可反映HCC患者的MVI状态,临床应用具有一定的可行性。 展开更多
关键词 T1 mapping 细胞外容积分数 肝细胞肝癌 微血管侵犯
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T1 mapping联合胆道-椎旁肌信号强度比预测肝功能的价值
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作者 马博洋 徐辉 +1 位作者 杨正汉 朱文雁 《中国医学影像学杂志》 CSCD 北大核心 2024年第7期699-703,708,共6页
目的探讨钆塞酸二钠增强MRI T1 mapping联合胆道-椎旁肌信号强度比评估肝功能的价值。资料与方法前瞻性收集北京友谊医院2020年8月—2022年2月72例行钆塞酸二钠增强MRI的患者,将患者按照肝功能Child-Pugh分级分为肝功能正常组22例、A级... 目的探讨钆塞酸二钠增强MRI T1 mapping联合胆道-椎旁肌信号强度比评估肝功能的价值。资料与方法前瞻性收集北京友谊医院2020年8月—2022年2月72例行钆塞酸二钠增强MRI的患者,将患者按照肝功能Child-Pugh分级分为肝功能正常组22例、A级组35例、B+C级组15例。患者均于增强前及增强后20 min扫描T1 mapping序列,测量肝实质的增强前及增强后(T1post)T1弛豫时间,并计算肝脏T1弛豫时间减少率(ΔT1)。在肝胆期图像上测量胆道信号及椎旁肌信号,计算胆道-椎旁肌信号强度比(SIR)。评价医师间测量结果的一致性,观察各指标与肝功能分级的相关性,比较不同组间各指标的差异和诊断效能。结果T1post与肝功能分级呈正相关(r=0.683,P<0.001),随肝功能受损程度加重逐渐增加。ΔT1、SIR、SIR×ΔT1与肝功能分级呈负相关(r=-0.764、-0.729、-0.826,P均<0.001),随肝功能受损程度加重逐渐减小。T1post、ΔT1、SIR、SIR×ΔT1在各肝功能分级组间差异均有统计学意义(F=27.491、55.782、48.410、46.809,P均<0.05);两两比较中,各指标差异均有统计学意义(P<0.05)。各指标中的诊断效能最优者为SIR×ΔT1,其鉴别肝功能正常组与肝硬化组、A级组与B+C级组的曲线下面积分别为0.915、0.984。结论T1post、ΔT1、SIR、SIR×ΔT1与肝功能Child-Pugh分级均有较强的相关性。SIR×ΔT1在各组间鉴别能力更好,可作为定量评估肝功能的影像指标。 展开更多
关键词 T1 mapping 信号强度比 肝功能 钆塞酸二钠 磁共振成像
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磁共振T1 mapping及ECV技术在扩张型心肌病中的应用进展
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作者 赵凯迪 曹新山 《磁共振成像》 CAS CSCD 北大核心 2024年第5期204-208,共5页
扩张型心肌病(dilated cardiomyopathy,DCM)是由心室腔扩张或者扩大而导致心肌收缩功能受损,这种病症属于一种常见的、有明显家族史的心血管系统疾病。心肌磁共振钆对比剂延迟强化(late gadolinium enhancement,LGE)可被广泛用作无创心... 扩张型心肌病(dilated cardiomyopathy,DCM)是由心室腔扩张或者扩大而导致心肌收缩功能受损,这种病症属于一种常见的、有明显家族史的心血管系统疾病。心肌磁共振钆对比剂延迟强化(late gadolinium enhancement,LGE)可被广泛用作无创心肌纤维化诊断的有效手段,但其对弥漫性心肌纤维化诊断的精确程度有所欠缺,因此在临床应用中存在一定的局限性。近年来,T1 mapping技术的临床应用为医学影像学带来了巨大的变革,特别是对于弥漫性心肌纤维化的诊断、识别、预后判断等,它可以以极高的精确度检测出T1值以及细胞外容积(extracellular volume,ECV),对DCM进行全方位评估。本文就T1 mapping及ECV在DCM患者的早期诊断、相关疾病鉴别、风险分层及预后评估和治疗疗效评估中的最新应用进展予以总结,旨在提高DCM的早期检出率,对患者的病情进展进行更加准确的判断,从而为患者制订出最佳的治疗策略,改善患者的预后,并有望为将来的研究提供参考。 展开更多
关键词 扩张型心肌病 心肌弥漫纤维化 T1 mapping 细胞外体积分数 磁共振成像 早期诊断
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Identification of candidate genes for early-maturity traits by combining BSA-seq and QTL mapping in upland cotton(Gossypium hirsutum L.) 被引量:1
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作者 Liang Ma Tingli Hu +7 位作者 Meng Kang Xiaokang Fu Pengyun Chen Fei Wei Hongliang Jian Xiaoyan Lü Meng Zhang Yonglin Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3472-3486,共15页
Cotton breeding for the development of early-maturing varieties is an effective way to improve multiple cropping indexes and alleviate the conflict between grains and cotton in the cultivated fields in China.In the pr... Cotton breeding for the development of early-maturing varieties is an effective way to improve multiple cropping indexes and alleviate the conflict between grains and cotton in the cultivated fields in China.In the present study,we aimed to identify upland cotton quantitative trait loci(QTLs)and candidate genes related to early-maturity traits,including whole growth period(WGP),flowering timing(FT),node of the first fruiting branch(NFFB),height of the node of the first fruiting branch(HNFFB),and plant height(PH).An early-maturing variety,CCRI50,and a latematuring variety,Guoxinmian 11,were crossed to obtain biparental populations.These populations were used to map QTLs for the early-maturity traits for two years(2020 and 2021).With BSA-seq analysis based on the data of population 2020,the candidate regions related to early maturity were found to be located on chromosome D03.We then developed 22 polymorphic insertions or deletions(InDel)markers to further narrow down the candidate regions,resulting in the detection of five and four QTLs in the 2020 and 2021 populations,respectively.According to the results of QTL mapping,two candidate regions(InDel_G286-InDel_G144 and InDel_G24-InDel_G43)were detected.In these regions,three genes(GH_D03G0451,GH_D03G0649,and GH_D03G1180)have nonsynonymous mutations in their exons and one gene(GH_D03G0450)has SNP variations in the upstream sequence between CCRI50 and Guoxinmian 11.These four genes also showed dominant expression in the floral organs.The expression levels of GH_D03G0451,GH_D03G0649 and GH_D03G1180 were significantly higher in CCRI50 than in Guoxinmian 11 during the bud differentiation stages,while GH_D03G0450 showed the opposite trend.Further functional verification of GH_D03G0451 indicated that the GH_D03G0451-silenced plants showed a delay in the flowering time.The results suggest that these are the candidate genes for cotton early maturity,and they may be used for breeding early-maturity cotton varieties. 展开更多
关键词 cotton genomics early-maturity traits BSA-seq QTL mapping molecular breeding
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Identification and fine mapping of qSW2 for leaf slow wilting in soybean 被引量:1
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作者 Shengyou Li Changling Wang +5 位作者 Chunjuan Yan Xugang Sun Lijun Zhang Yongqiang Cao Wenbin Wang Shuhong Song 《The Crop Journal》 SCIE CSCD 2024年第1期244-251,共8页
Drought is one of the abiotic stresses limiting the production of soybean(Glycine max).Elucidation of the genetic and molecular basis of the slow-wilting(SW)trait of this crop offers the prospect of its genetic improv... Drought is one of the abiotic stresses limiting the production of soybean(Glycine max).Elucidation of the genetic and molecular basis of the slow-wilting(SW)trait of this crop offers the prospect of its genetic improvement.A panel of 188 accessions and a set of recombinant inbred lines produced from a cross between cultivars Liaodou 14 and Liaodou 21 were used to identify quantitative-trait loci(QTL)associated with SW.Plants were genotyped by Specific-locus amplified fragment sequencing and seedling leaf wilting was assessed under three water-stress treatments.A genome-wide association study identified 26 SW-associated single-nucleotide polymorphisms(SNPs),including three located in a 248-kb linkage-disequilibrium(LD)block on chromosome 2.Linkage mapping revealed a major-effect QTL,qSW2,associated with all three treatments and adjacent to the LD block.Fine mapping in a BC_(2)F_(3) population derived from a backcross between Liaodou 21 and R26 confined qSW2 to a 60-kb interval.Gene expression and sequence variation analysis identified the gene Glyma.02 g218100,encoding an auxin transcription factor,as a candidate gene for qSW2.Our results will contribute significantly to improving drought-resistant soybean cultivars by providing genetic information and resources. 展开更多
关键词 Drought GWAS Linkage mapping Slow wilting Soybean(Glycine max)
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Exploring deep learning for landslide mapping:A comprehensive review 被引量:1
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作者 Zhi-qiang Yang Wen-wen Qi +1 位作者 Chong Xu Xiao-yi Shao 《China Geology》 CAS CSCD 2024年第2期330-350,共21页
A detailed and accurate inventory map of landslides is crucial for quantitative hazard assessment and land planning.Traditional methods relying on change detection and object-oriented approaches have been criticized f... A detailed and accurate inventory map of landslides is crucial for quantitative hazard assessment and land planning.Traditional methods relying on change detection and object-oriented approaches have been criticized for their dependence on expert knowledge and subjective factors.Recent advancements in highresolution satellite imagery,coupled with the rapid development of artificial intelligence,particularly datadriven deep learning algorithms(DL)such as convolutional neural networks(CNN),have provided rich feature indicators for landslide mapping,overcoming previous limitations.In this review paper,77representative DL-based landslide detection methods applied in various environments over the past seven years were examined.This study analyzed the structures of different DL networks,discussed five main application scenarios,and assessed both the advancements and limitations of DL in geological hazard analysis.The results indicated that the increasing number of articles per year reflects growing interest in landslide mapping by artificial intelligence,with U-Net-based structures gaining prominence due to their flexibility in feature extraction and generalization.Finally,we explored the hindrances of DL in landslide hazard research based on the above research content.Challenges such as black-box operations and sample dependence persist,warranting further theoretical research and future application of DL in landslide detection. 展开更多
关键词 Landslide mapping Quantitative hazard assessment Deep learning Artificial intelligence Neural network Big data Geological hazard survery engineering
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NIPT-plus筛查染色体MMS的应用评价
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作者 陈英 童晓青 +3 位作者 余学高 黄浩 黄彬 陈培松 《分子诊断与治疗杂志》 2024年第1期10-14,共5页
目的探讨扩展性无创产前检测(NIPT-plus)在筛查染色体微缺失/重复综合征(MMS)上的应用。方法选取中山大学附属第一医院2018年1月至2020年12月3860例孕妇及2022年10例室间质评样本的NIPT和NIPT-plus检测结果,其中24例孕妇进行染色体微阵... 目的探讨扩展性无创产前检测(NIPT-plus)在筛查染色体微缺失/重复综合征(MMS)上的应用。方法选取中山大学附属第一医院2018年1月至2020年12月3860例孕妇及2022年10例室间质评样本的NIPT和NIPT-plus检测结果,其中24例孕妇进行染色体微阵列分析(CMA)产前诊断。结果24例孕妇及10例质评样本NIPT-plus游离DNA浓度明显高于NIPT,总测序数据量提高了1.39~1.58倍,有效测序数据量提高了1.20~1.35倍;24例孕妇样本NIPT-plus提示1例18-三体,1例21-三体,2例MMS,NIPT提示1例18-三体,1例21-三体;10例质评样本NIPT-plus提示9例MMS且9号样本同时存在性染色体非整倍体(SCAs),NIPT仅提示1例SCAs。结论在本院系统检测范围内NIPT-plus能有效应用于MMS的筛查,减少出生缺陷。 展开更多
关键词 扩展性无创产前检测 染色体微缺失/重复综合征 灵敏度
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3.0T磁共振T2 mapping在腰椎间盘退行性变分级评估中的应用
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作者 霍平 高翔 《山西卫生健康职业学院学报》 CAS 2024年第2期28-30,共3页
目的:探究3.0T磁共振(MRI)T2弛豫时间图(T2 mapping)在腰椎间盘退行性变分级评估中的应用价值。方法:选取200例腰椎间盘退变患者作为研究对象,应用GE Discovery 750W 3.0T MRI成像系统对椎间盘进行扫描,扫描序列包括常规腰椎MRI以及T2 m... 目的:探究3.0T磁共振(MRI)T2弛豫时间图(T2 mapping)在腰椎间盘退行性变分级评估中的应用价值。方法:选取200例腰椎间盘退变患者作为研究对象,应用GE Discovery 750W 3.0T MRI成像系统对椎间盘进行扫描,扫描序列包括常规腰椎MRI以及T2 mapping序列,在T2加权像(T2WI)上依据Pfirrmann分级法对腰椎间盘进行评级,绘制ROC曲线分析T2值对Pfirrmann分级诊断的效能。结果:本研究200例受检者共1000个椎间盘,其中Pfirrmann分级Ⅰ~Ⅴ级分别为110例、370例、460例、50例和10例。Ⅰ~Ⅴ级间前纤维环、后纤维环以及髓核的T2值比较差异具有统计学意义(P<0.05);前纤维环、后纤维环以及髓核T2值中,Ⅳ级与Ⅴ级间比较差异均无统计学意义(P>0.05),其余各组间Ⅰ~Ⅱ级、Ⅱ~Ⅲ级、Ⅲ~Ⅳ级髓核T2值比较差异均有统计学意义(P<0.05)。Pearson相关分析显示,髓核的T2值与Pfirrmann分级呈负相关(r=-0.57,P<0.05)。PfirrmannⅠ~Ⅱ级、Ⅱ~Ⅲ级、Ⅲ~Ⅳ级腰椎间盘髓核T2值的AUC分别为0.770、0.775、0.824,对应的cut off值分别为129.96ms、106.02ms、74.40ms(P<0.05)。结论:3.0T MRI T2 Mapping检查可用于腰椎间盘退变分级评估,髓核T2值能够为影像学量化诊断腰椎间盘退变程度提供依据。 展开更多
关键词 椎间盘退变 T2 mapping成像 Pfirrmann分级 诊断
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B1场校正T1 mapping用于鉴别肺癌病理分型及分化程度
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作者 李真真 徐高峰 +5 位作者 符益纲 肖勇 朱明明 周笑 史讯 江建芹 《中国医学影像技术》 CSCD 北大核心 2024年第2期231-234,共4页
目的 观察B1场校正T1 mapping用于鉴别肺癌病理分型及分化程度的价值。方法 前瞻性纳入65例肺癌患者共74处病灶,包括低分化49处、中高分化25处,其中腺癌42处、鳞癌14处、小细胞肺癌(均为低分化)18处。采集B1场校正T1 mapping图像;以2种... 目的 观察B1场校正T1 mapping用于鉴别肺癌病理分型及分化程度的价值。方法 前瞻性纳入65例肺癌患者共74处病灶,包括低分化49处、中高分化25处,其中腺癌42处、鳞癌14处、小细胞肺癌(均为低分化)18处。采集B1场校正T1 mapping图像;以2种方法勾画ROI(ROI1、ROI2),观察不同病理分型及不同分化程度肺癌T1值的差异;绘制受试者工作特征(ROC)曲线,计算曲线下面积(AUC),评估B1场校正T1 mapping鉴别肺癌病理分型及分化程度的价值。结果 不同病理分型肺癌T1值差异均有统计学意义(P均<0.05);小细胞肺癌与其他2种类型肺癌T1值差异均有统计学意义(P均<0.05)。低与中高分化肺癌(鳞癌+腺癌)T1值差异有统计学意义(P均<0.05)。以ROI1 T1值=1 524.21 ms为截断值,其鉴别低与中高分化肺癌(鳞癌+腺癌)的AUC为0.698,敏感度为64.50%,特异度为76.00%;而以ROI2 T1值=1 630.68 ms为截断值,其AUC为0.676,敏感度为54.80%,特异度为80.00%。结论 B1场校正T1 mapping有助于鉴别肺癌病理分型及分化程度。 展开更多
关键词 肺肿瘤 病理学 磁共振成像 T1 mapping 前瞻性研究
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Integrated Geological and Geophysical Mapping for Groundwater Potential Studies at Ekwegbe-Agu and Environs, Enugu State, Nigeria
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作者 Charles Chibueze Ugbor Ugochukwu Kingsley Ogbodo Osita Kelechi Eze 《Open Journal of Geology》 CAS 2024年第4期513-547,共35页
The study integrates both the geological and geophysical mapping techniques for groundwater potential studies at Ekwegbe-Agu and the environs, Enugu state, Nigeria for optimal citing of borehole. Located in the Anambr... The study integrates both the geological and geophysical mapping techniques for groundwater potential studies at Ekwegbe-Agu and the environs, Enugu state, Nigeria for optimal citing of borehole. Located in the Anambra Basin between latitudes 6˚43'N and 6˚47'N and longitudes 7˚28'E and 7˚32'E, it is stratigraphycally underlain by, from bottom to top, the Enugu/Nkporo, Mamu and Ajali Formation respectively, a complex geology that make citing of productive borehole in the area problematic leading to borehole failure and dry holes due to inadequate sampling. The study adopted a field and analytic sampling approach, integrating field geological, electrical resistivity and self-potential methods. The software, SedLog v3.1, InterpexIx1Dv.3, and Surfer v10 were employed for the data integration and interpretation. The result of the geological field and borehole data shows 11 sedimentary facies consisting of sandstone, shales and heterolith of sandstone/shale, with the aquifer zone mostly prevalent in the more porous sand-dominated horizons. Mostly the AK and HK were the dominant curve types. An average of 6 geo-electric layers were delineated across all transects with resistivity values ranging from 25.42 - 105.85 Ωm, 186.38 - 3383.3 Ωm, and 2992 - 6286.4 Ωm in the Enugu, Mamu and Ajali Formations respectively. The resistivity of the main aquifer layer ranges from 1 to 500 Ωm. The aquifer thickness within the study area varies between 95 and 140 m. The western and northwestern part of the study area which is underlain mainly by the Ajali Formation showed the highest groundwater potential in the area and suitable for citing productive boreholes. 展开更多
关键词 SEISMIC Ekwegbe-Agu GROUNDWATER RESISTIVITY Field mapping Borehole Logging
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B1场校正T1 mapping可作为肺结节良恶性诊断及病理分型的有效影像学检查方法
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作者 洪琴 肖勇 +3 位作者 符益纲 周笑 朱明明 江建芹 《分子影像学杂志》 2024年第7期741-745,共5页
目的 探讨B1场校正T1 mapping在肺结节诊断及病理分型中的临床价值。方法 收集2020年8月~2022年7月在盐城市第一人民医院行肺部B1场校正T1 mapping扫描的54例患者,共计57个肺结节,其中良性17个,恶性40个。由2位独立测量者A、B手动勾画... 目的 探讨B1场校正T1 mapping在肺结节诊断及病理分型中的临床价值。方法 收集2020年8月~2022年7月在盐城市第一人民医院行肺部B1场校正T1 mapping扫描的54例患者,共计57个肺结节,其中良性17个,恶性40个。由2位独立测量者A、B手动勾画测量病灶的初始T1均值,测量者之间可重复性使用组内相关系数进行评价;比较T1均值在良恶性肺结节之间的差异;采用ROC曲线分析区分良恶性肺结节的最佳阈值;采用单因素方差分析评估T1均值在不同病理学类型肺结节之间的差异。结果 肺结节的T1均值在观察者内及观察者之间均显示了较好的测量可重复性(组内相关系数为0.977、0.953)。测量者A及测量者B测得良性肺结节的T1均值分别为1615.98±337.28 ms、1618.52±362.82 ms,测得恶性肺结节的T1均值分别为1376.87±262.50 ms、1392.51±301.30 ms;良性肺结节的T1均值比恶性肺结节更高(P=0.006、P=0.020)。ROC曲线显示,以T1=1350.33 ms为界值进行诊断,恶性肺结节的敏感度为53.66%,特异度为87.50%,ROC曲线下面积为0.720(95%CI:0.586~0.831)。其中T1均值在腺癌、鳞癌及小细胞肺癌中存在差异(测量者A、B:P=0.009、P=0.010)。小细胞肺癌的T1均值高于腺癌和鳞癌的T1均值(P=0.003、P=0.049),但是腺癌和鳞癌之间的T1均值的差异无统计学意义(P=0.944、P=0.774)。结论 B1场校正T1 mapping成像具有良好的可重复性,可成为肺结节良恶性鉴别及病理诊断的快速的、无辐射的定量影像学检查方法。 展开更多
关键词 肺癌 肺结节 T1 mapping 诊断 病理
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Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique
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作者 Alassane Traore Anna Ndiaye +6 位作者 Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期97-106,共10页
Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micr... Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species. 展开更多
关键词 PIXE 2D mapping Rice Concentration Elemental Analysis
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The DNA damage repair complex MoMMS21-MoSMC5 is required for infection-related development and pathogenicity of Magnaporthe oryzae
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作者 Yue Jiang Rong Wang +8 位作者 Lili Du Xueyu Wang Xi Zhang Pengfei Qi Qianfei Wu Baoyi Peng Zonghua Wang Mo Wang Ya Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1956-1966,共11页
The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic ... The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic fungi,particularly in the highly destructive rice blast fungus Magnaporthe oryzae,remains unknown.In this study,we functionally characterized the homologues of this complex,MoMMS21 and MoSMC5,in M.oryzae.We first demonstrated the importance of DNA damage repair in M.oryzae by showing that the DNA damage inducer phleomycin inhibited vegetative growth,infection-related development and pathogenicity in this fungus.Additionally,we discovered that MoMMS21 and MoSMC5 interacted in the nuclei,suggesting that they also function as a complex in M.oryzae.Gene deletion experiments revealed that both MoMMS21 and MoSMC5 are required for infection-related development and pathogenicity in M.oryzae,while only MoMMS21 deletion affected growth and sensitivity to phleomycin,indicating its specific involvement in DNA damage repair.Overall,our results provide insights into the roles of MoMMS21 and MoSMC5 in M.oryzae,highlighting their functions beyond DNA damage repair. 展开更多
关键词 Magnaporthe oryzae mms21 SMC5 DNA damage repair PATHOGENICITY
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Combining QTL Mapping and Multi-Omics Identify Candidate Genes for Nutritional Quality Traits during Grain Filling Stage in Maize
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作者 Pengcheng Li Tianze Zhu +7 位作者 Yunyun Wang Shuangyi Yin Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Zefeng Yang Chenwu Xu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1441-1453,共13页
The nutritional composition and overall quality of maize kernels are largely determined by the key chemical com-ponents:protein,oil,and starch.Nevertheless,the genetic basis underlying these nutritional quality traits... The nutritional composition and overall quality of maize kernels are largely determined by the key chemical com-ponents:protein,oil,and starch.Nevertheless,the genetic basis underlying these nutritional quality traits during grainfilling remains poorly understood.In this study,the concentrations of protein,oil,and starch were studied in 204 recombinant inbred lines resulting from a cross between DH1M and T877 at four different stages post-pollination.All the traits exhibited considerable phenotypic variation.During the grain-filling stage,the levels of protein and starch content generally increased,whereas oil content decreased,with significant changes observed between 30 and 40 days after pollination.Quantitative trait locus(QTL)mapping was conducted and a total of 32 QTLs,comprising 14,12,and 6 QTLs for grain protein,oil,and starch content were detected,respectively.Few QTLs were consistently detectable across different time points.By integrating QTL analysis,glo-bal gene expression profiling,and comparative genomics,we identified 157,86,and 54 differentially expressed genes harboring nonsynonymous substitutions between the parental lines for grain protein,oil,and starch con-tent,respectively.Subsequent gene function annotation prioritized 15 candidate genes potentially involved in reg-ulating grain quality traits,including those encoding transcription factors(NAC,MADS-box,bZIP,and MYB),cell wall invertase,cellulose-synthase-like protein,cell division cycle protein,trehalase,auxin-responsive factor,and phloem protein 2-A13.Our study offers significant insights into the genetic architecture of maize kernel nutritional quality and identifies promising QTLs and candidate genes,which are crucial for the genetic enhance-ment of these traits in maize breeding programs. 展开更多
关键词 MAIZE protein oil STARCH QTL mapping candidate genes
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