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Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings 被引量:9
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作者 WU Jian-rong LIU Hai-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期504-510,共7页
In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings a... In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained. 展开更多
关键词 sequence of set-valued mappings common fixed point random fixed point metric space
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Formal Concept Analysis Based on Set-valued Mapping
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作者 CHEN Li-ya HUANG Tao +1 位作者 SONG Zhen-ming PEI Zheng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期390-396,共7页
Formal concept analysis (FCA) is a discipline that studied the hierarchical structures induced by a binary relation between a pair of sets, and applies in data analysis, information retrieval, knowledge discovery, e... Formal concept analysis (FCA) is a discipline that studied the hierarchical structures induced by a binary relation between a pair of sets, and applies in data analysis, information retrieval, knowledge discovery, etc. In this paper, it is shown that a formal context T is equivalent to a set-valued mapping S : G → P(М), and formal concepts could be defined in the set-valued mapping S. It is known that the topology and set-valued mapping are linked. Hence, the advantage of this paper is that the conclusion make us to construct formal concept lattice based on the topology. 展开更多
关键词 FCA set-valued mapping ISOMORPHISM
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Natural Mappings on Set-valued Mapping Spaces
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作者 LI Zu-quan WANG Jiu-jing 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期21-25,共5页
In this paper,we discuss the continuities of some natural mappings on pointcompact continuous set-valued mapping spaces with compact-open topology and obtain the properties of set-valued injective mappings,set-valued ... In this paper,we discuss the continuities of some natural mappings on pointcompact continuous set-valued mapping spaces with compact-open topology and obtain the properties of set-valued injective mappings,set-valued diagonal mappings,induced mappings,set-valued evaluation mappings,set-valued topological sum mappings and set-valued topological product mappings. 展开更多
关键词 set-valued mapping compact-open topology natural mapping
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Common Fixed Point Theorems of Single-valued and Set-valued Mappings in Complete,Convex Metric Spaces 被引量:1
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作者 LIANGJun-qi ZHANGZhi-hong ZHAOLing 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期264-270,共7页
Under the conditions of compatility or sub -c ompatility between a sigle-valued mapping and set-valued mapping, this paper d iscusses the existence of common fixed points for two set-valued mappings and a single-value... Under the conditions of compatility or sub -c ompatility between a sigle-valued mapping and set-valued mapping, this paper d iscusses the existence of common fixed points for two set-valued mappings and a single-valued mapping in complete, convex matric spaces. We extend and develop the main results. 展开更多
关键词 complete convex metric spaces compatible mappings s ub-compatible mappings common fixed point theorems
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A FIXED POINT THEOREM FOR SET-VALUED MAPPINGS
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作者 Amitabh Banerjee 1, Thakur Balwant Singh 2 (1 Department of Mathematics, Govt D B Girls P G College, Raipur (M P), 492001, India 2 Govt B H S S, Gariaband, Dist Raipur (M P), 493889, India) (Communicated by CHIEN Wei_zang) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第12期1397-1403,共7页
Fixed points for set_valued mappings from a metric space X (not necessarily complete) into B(X), the collection of nonempty bounded subsets of X are obtained. The result generalizes some known results.
关键词 fixed point set_valued mappings metric space
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A survey of ergodicity on the set-valued mappings
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作者 ZHANGYu-cheng LIAOGong-fu 《海南师范学院学报(自然科学版)》 2004年第4期305-311,共7页
In this paper, we give a survey on the PhD thesis of the first author. There theexistence and ergodicity on invariant measures of set-valued mappings are discused.
关键词 set-valued mapping INVARIANT measure ERGODIC MARKOV operator Mark-ov transition function lower SEMICONTINUOUS continuous selection
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A REMARK ON THE DERIVATE OF SET-VALUED MAPPING 被引量:1
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作者 Chen Bing(Dept. of Math. Jinzhou Teachers CollegeJinzhou 121003) 《数学研究》 CSCD 1994年第1期51-55,共5页
AREMARKONTHEDERIVATEOFSET-VALUEDMAPPING¥ChenBing(Dept.ofMath.JinzhouTeachersCollegeJinzhou121003)Abstract:Th... AREMARKONTHEDERIVATEOFSET-VALUEDMAPPING¥ChenBing(Dept.ofMath.JinzhouTeachersCollegeJinzhou121003)Abstract:Thederivateofset-va... 展开更多
关键词 集值映射 H-导出数 集值积分 巴拿赫空间
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磁共振集合序列技术替代T_(2) Mapping成像对成人膝关节软骨定量分析价值
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作者 武金龙 杨慧 《实用医学影像杂志》 2026年第1期32-35,共4页
目的分析使用磁共振集合序列(MAGIC)技术替代传统T_(2) Mapping成像定量分析成人膝关节关节软骨的临床价值。方法收集本院体检受试者36例,分为3组21~30岁,11例;31~40岁,10例;41~50岁,15例,分别行MAGIC和T_(2) Mapping扫描,比较软骨MAGIC... 目的分析使用磁共振集合序列(MAGIC)技术替代传统T_(2) Mapping成像定量分析成人膝关节关节软骨的临床价值。方法收集本院体检受试者36例,分为3组21~30岁,11例;31~40岁,10例;41~50岁,15例,分别行MAGIC和T_(2) Mapping扫描,比较软骨MAGIC T_(2)值与T_(2) Mapping T_(2)值是否存在差异。比较各年龄段胫骨内侧平台软骨、胫骨外侧平台软骨、股骨内侧髁软骨、股骨外侧髁软骨、髌骨表面软骨差异。结果MAGIC与T_(2) Mapping 2种方法分别对膝关节的不同部位关节软骨定量T_(2)值分析,2种方法对比差异无统计学意义(P>0.05)。41~50岁与21~30岁关节软骨厚度差异有统计学意义。利用MAGIC技术发现41~50岁与21~30岁各部位关节软骨T_(2)测值差异有统计学意义(P<0.05)。结论MAGIC技术能代替传统T_(2) Mapping成像方法定量分析成人膝关节软骨。 展开更多
关键词 膝关节 软骨 成人 磁共振集合序列 T_(2)mapping 定量分析
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Transitivity,mixing and chaos for a class of set-valued mappings 被引量:9
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作者 LIAO Gongfu WANG Lidong ZHANG Yucheng 《Science China Mathematics》 SCIE 2006年第1期1-8,共8页
Consider the continuous map f:x→X and the continuous map f of K,(X)into itself induced by f,where X is a metric space and K(X)the space of all non-empty compact subsets of x endowed with the Hausdorff metric.Accordin... Consider the continuous map f:x→X and the continuous map f of K,(X)into itself induced by f,where X is a metric space and K(X)the space of all non-empty compact subsets of x endowed with the Hausdorff metric.According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli,we investigate the relations between f and f in the related dynamical properties such as transitivity,weakly mixing and mixing,etc.And by using the obtained results,we give the satisfied answers to Roman-Flores's question and Fedeli's question. 展开更多
关键词 set-valued mapping TRANSITIVITY weak mixing MIXING chaos.
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Native T1 mapping值显著延长心脏纤维瘤一例
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作者 文涛 张辉 +3 位作者 甘铁军 胡万均 李世兰 张静 《磁共振成像》 北大核心 2026年第1期120-122,共3页
本研究为回顾性研究,遵守《赫尔辛基宣言》,并经兰州大学第二医院伦理委员会审核批准,免除受试者知情同意,批准文号:2025A-547。患儿,女,2月8天,因“发现心脏肿瘤2月”于2024年11月就诊于我院,患儿于2个月前出生后外院检查提示左心室肿... 本研究为回顾性研究,遵守《赫尔辛基宣言》,并经兰州大学第二医院伦理委员会审核批准,免除受试者知情同意,批准文号:2025A-547。患儿,女,2月8天,因“发现心脏肿瘤2月”于2024年11月就诊于我院,患儿于2个月前出生后外院检查提示左心室肿瘤,未予特殊诊治,现为进一步明确诊治收住我院心脏外科。患儿足月(38+6周)、顺产、无心脏肿瘤家族史。查体:心前区无隆起,心界不大,心音有力、律齐,胸骨左缘第2~3肋间可闻及3/6及吹风样杂音,静息血氧饱和度100%。 展开更多
关键词 心脏肿瘤 心脏纤维瘤 多模态磁共振成像 心脏磁共振 Native T1 mapping
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T2 Mapping联合DWI序列评估直肠癌脉管侵犯价值研究
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作者 李茜玮 陈安良 +2 位作者 王楠 林良杰 刘爱连 《中国CT和MRI杂志》 2026年第1期149-152,共4页
目的探讨T2 mapping与DWI序列预测直肠癌脉管侵犯的价值。方法回顾性分析经本院行3.0T MRI扫描且经术后病理证实的直肠癌脉管侵犯13例,脉管非侵犯20例,2名观察者分别于瘤体显示最大层面参考增强动脉期图像及DWI图像于T2 mapping及ADC图... 目的探讨T2 mapping与DWI序列预测直肠癌脉管侵犯的价值。方法回顾性分析经本院行3.0T MRI扫描且经术后病理证实的直肠癌脉管侵犯13例,脉管非侵犯20例,2名观察者分别于瘤体显示最大层面参考增强动脉期图像及DWI图像于T2 mapping及ADC图像上测量病灶T2值及ADC值。采用组内相关系数(intraclass correlation cofficient,ICC)评估两名观察者测量参数值的一致性。采用独立样本t检验或Mann-Whitney U检验分析两组病例各参数的差异。采用Logistic回归计算有统计学差异的参数联合评估直肠癌LVI的预测值。采用ROC曲线评估有差异参数单独或联合的诊断效能,并利用De-Long检验比较各ROC曲线间的差异。采用Pearson相关性检验分析两参数值的相关性。结果2名观察者测量T2值及ADC值一致性好(ICC>0.75)。脉管侵犯组的T2值及ADC值低于非脉管侵犯组(77.15±6.95ms、0.69±0.15mm^(2)/s vs 87.04±7.75ms、0.90±0.21 mm^(2)/s,P<0.05)。ADC值与ADC-T2联合鉴别两组疾病的AUC值比较差异具有统计学意义(P=0.036)。结论T2 mapping和DWI序列可预测直肠癌脉管侵犯,两序列联合效能提升,因此T2值与ADC值联合可为临床诊疗直肠癌脉管侵犯提供参考信息。 展开更多
关键词 直肠癌 脉管侵犯 磁共振成像 T2 mapping成像 弥散加权成像
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On Ekeland's Variational Principle for Set-Valued Mappings
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作者 Sheng-jie Li Wen-yan Zhang 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2007年第1期141-148,共8页
In this paper, we derive a general vector Ekeland variational principle for set-valued mappings, which has a dosed relation to εk^0 -efficient points of set-valued optimization problems. The main result presented in ... In this paper, we derive a general vector Ekeland variational principle for set-valued mappings, which has a dosed relation to εk^0 -efficient points of set-valued optimization problems. The main result presented in this paper is a generalization of the corresponding result in [3]. 展开更多
关键词 Vector Ekeland variational principle nonlinear scalarization function metric space set-valued mapping
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Coincidence Theorem for Admissible Set-valued Mappings and Its Applications in FC-spaces
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作者 Ming-ge Yang Lei Deng 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第3期455-462,共8页
A new coincidence theorem for admissible set-valued mappings is proved in FC-spaces with a more general convexity structure. As applications, an abstract variational inequality, a KKM type theorem and a fixed point th... A new coincidence theorem for admissible set-valued mappings is proved in FC-spaces with a more general convexity structure. As applications, an abstract variational inequality, a KKM type theorem and a fixed point theorem are obtained. Our results generalize and improve the corresponding results in the literature. 展开更多
关键词 FC-SPACE coincidence theorem admissible set-valued mapping
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Proximal point algorithm for a new class of fuzzy set-valued variational inclusions with (H,η)-monotone mappings
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作者 李红刚 《Journal of Chongqing University》 CAS 2008年第1期79-84,共6页
We introduced a new class of fuzzy set-valued variational inclusions with (H,η)-monotone mappings. Using the resolvent operator method in Hilbert spaces, we suggested a new proximal point algorithm for finding approx... We introduced a new class of fuzzy set-valued variational inclusions with (H,η)-monotone mappings. Using the resolvent operator method in Hilbert spaces, we suggested a new proximal point algorithm for finding approximate solutions, which strongly converge to the exact solution of a fuzzy set-valued variational inclusion with (H,η)-monotone. The results improved and generalized the general quasi-variational inclusions with fuzzy set-valued mappings proposed by Jin and Tian Jin MM, Perturbed proximal point algorithm for general quasi-variational inclusions with fuzzy set-valued mappings, OR Transactions, 2005, 9(3): 31-38, (In Chinese); Tian YX, Generalized nonlinear implicit quasi-variational inclusions with fuzzy mappings, Computers & Mathematics with Applications, 2001, 42: 101-108. 展开更多
关键词 variational inclusion (H η)-monotone mapping resolvent operator technique fuzzy set-valued mapping proximal point algorithm: convergence of numerical methods
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MRI T2 Mapping定量参数与乳腺癌临床分期的关系研究
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作者 马书敏 岳志领 +4 位作者 李莹 许彩红 王静静 王娜 李建丽 《中国CT和MRI杂志》 2026年第3期76-79,共4页
目的分析磁共振成像(MRI)T2 mapping定量参数与乳腺癌临床分期的关系。方法回顾性分析2023年8月~2024年8月邯郸市中心医院收治的86例乳腺癌患者的临床资料,根据病理结果分为中早期组(54例)和晚期组(32例)。比较两组患者基线资料、MRI图... 目的分析磁共振成像(MRI)T2 mapping定量参数与乳腺癌临床分期的关系。方法回顾性分析2023年8月~2024年8月邯郸市中心医院收治的86例乳腺癌患者的临床资料,根据病理结果分为中早期组(54例)和晚期组(32例)。比较两组患者基线资料、MRI图像特征(形态、边缘、强化方式及纤维腺体类型)及T2 mapping定量参数(10th位数、90th位数、熵值及平均值)。绘制受试者工作特征曲线,以曲线下面积(AUC)评估T2 mapping定量参数对晚期乳腺癌的诊断效能。使用Pearson法分析T2 mapping定量参数与晚期乳腺癌的关系。结果两组患者基线资料、形态、边缘、强化方式、纤维腺体类型、90th位数及熵值比较,差异无统计学意义(P>0.05)。晚期组10th位数、平均值小于中早期组(P<0.05)。ROC曲线显示,T2 mapping定量参数中的10th位数、平均值诊断晚期乳腺癌的AUC分别为0.826、0.870,二者联合(并联)诊断晚期乳腺癌的AUC为0.899(95%CI:0.815~0.954),敏感度为87.50%,特异度为83.33%,联合诊断AUC高于单独指标(Z=6.997、9.274,均P<0.05)。Pearson法分析结果显示,T2 mapping定量参数中的10th位数、平均值与晚期乳腺癌呈明显负相关(P<0.05)。结论MRI T2 mapping定量参数中的10th位数、平均值与晚期乳腺癌呈明显相关性,可用于评估乳腺癌临床分期,联合检测有助于提高诊断准确性。 展开更多
关键词 磁共振成像 T2mapping定量参数 乳腺癌 临床分期 相关性
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A Fixed Point Theorem for Set-Valued Mapping in Abstract Convex Space with Application
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作者 范晓冬 向淑文 《Journal of Mathematical Research and Exposition》 CSCD 2009年第4期716-720,共5页
A new fixed point theorem and the selection property for upper semi-continuous set-valued mappings in abstract convexity space are established. As their applications the existence of Nash equilibrium for n-person non-... A new fixed point theorem and the selection property for upper semi-continuous set-valued mappings in abstract convexity space are established. As their applications the existence of Nash equilibrium for n-person non-cooperative generalized games is proved. 展开更多
关键词 set-valued mapping fixed point continuous selection Nash equilibrium.
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Continuous selections for pseudo-lower semicontinuous set-valued mappings on convex structure spaces and hyperspace contractibility
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作者 Li, L Wu, CX 《Chinese Science Bulletin》 SCIE EI CAS 1997年第14期1230-1231,共2页
SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is... SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is introduced, and a convex structure of metric space is de-fined. A continuous selection theorem for pseudo-lower semicontinuity is given. This 展开更多
关键词 Continuous selections for pseudo-lower semicontinuous set-valued mappings on convex structure spaces and hyperspace contractibility
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T1 Mapping联合扩散加权成像构建多模态预测模型在乳腺肿块良恶性鉴别中的应用研究
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作者 吴小敏 赖燕琴 +2 位作者 廖雪燕 罗珊 林丹丹 《生物医学工程学进展》 2026年第1期63-68,共6页
目的评估T1 Mapping联合扩散加权成像(diffusion-weighted imaging,DWI)在乳腺肿块良恶性鉴别中的诊断价值,并分析其与Ki-67表达的相关性。方法回顾性纳入96例经病理证实的乳腺肿块患者,比较T1值、T1+值、△T1%、T2值及表观弥散系数(app... 目的评估T1 Mapping联合扩散加权成像(diffusion-weighted imaging,DWI)在乳腺肿块良恶性鉴别中的诊断价值,并分析其与Ki-67表达的相关性。方法回顾性纳入96例经病理证实的乳腺肿块患者,比较T1值、T1+值、△T1%、T2值及表观弥散系数(apparent diffusion coefficient,ADC)的差异,采用Logistic回归构建联合模型并进受试者操作特征(receiver operating characteristic,ROC)曲线分析,同时评估MRI参数与Ki-67的Spearman相关性。结果恶性肿块T1值、T1+值及△T1%均显著高于良性肿块,ADC显著低于良性(均P<0.05)。多因素分析显示△T1%与ADC为独立预测因子。联合模型的曲线下面积(area under the curve,AUC)为0.941,优于各单项MRI定量指标。Ki-67高表达组△T1%升高、ADC降低(均P<0.05),且△T1%与Ki-67呈正相关(r=0.462),ADC与Ki-67呈负相关(r=−0.518)。结论T1 Mapping联合DWI可显著提高乳腺肿块良恶性的鉴别效能,△T1%与ADC具有重要的诊断价值,并可反映肿瘤的增殖活性。 展开更多
关键词 T1 mapping 扩散加权成像 乳腺肿块 表观弥散系数 Ki-67
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多b值DWI与T2 mapping定量技术诊断前列腺癌与前列腺增生结节价值研究
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作者 王旭 陈婷 +1 位作者 王姗 谢晓平 《哈尔滨医药》 2026年第1期4-7,共4页
目的研究多b值扩散加权序列(diffusion-weighted sequence,DWI)与T2 mapping序列定量值鉴别前列腺癌(Prostate cancer,PCa)与前列腺增生(Benign Prostatic Hyperplasia,BPH)的诊断价值。方法回顾性分析在南通大学附属江阴医院放射科MRI... 目的研究多b值扩散加权序列(diffusion-weighted sequence,DWI)与T2 mapping序列定量值鉴别前列腺癌(Prostate cancer,PCa)与前列腺增生(Benign Prostatic Hyperplasia,BPH)的诊断价值。方法回顾性分析在南通大学附属江阴医院放射科MRI检查并获得病理证实PCa患者67例、BPH患者66例影像资料。两组病例分别测得b=1000、2000s/mm^(2)扩散加权成像(DWI)的ADC值及T2 mapping值,比较两组间不同b值ADC值和T2值差异,受试者工作特征(ROC)曲线分析各参数及ADC_(2000)-T2联合模型的诊断效能。结果PCa组ADC_(1000)值、ADC_(2000)值、T2值均低于BPH组,差异有统计学意义(P<0.01)。ADC_(1000)值、ADC_(2000)值、T2值以及ADC_(2000)-T2联合模型鉴别PCa与BPH的AUC值分别为0.80、0.83、0.89及0.92。ADC_(2000)-T2 mapping联合模型诊断效能优于单独ADC_(1000)值、ADC_(2000)值,差异有统计学意义(P<0.01)。结论DWI、T2 mapping序列定量值诊断PCa与BPH有较好的鉴别价值,而且联合高b值DWI、T2 mapping联合模型诊断效能有所提升,能够为临床诊断PCa提供较好的诊断依据。 展开更多
关键词 前列腺癌 前列腺增生 扩散加权序列 T2 mapping序列
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