期刊文献+
共找到101篇文章
< 1 2 6 >
每页显示 20 50 100
关于角量的标量性与矢量性
1
作者 籍延坤 于华明 《抚顺石油学院学报》 EI 2001年第4期74-77,共4页
无限小角位移、有限大角位移、角速度、平均角速度、角加速度、平均角加速度和角坐标的增量以及角坐标对时间的一阶和二阶导数不仅是物理学中常用的物理量 ,而且也是很重要的物理概念。物理量又分为标量、矢量和张量 ,若物理量是矢量 ,... 无限小角位移、有限大角位移、角速度、平均角速度、角加速度、平均角加速度和角坐标的增量以及角坐标对时间的一阶和二阶导数不仅是物理学中常用的物理量 ,而且也是很重要的物理概念。物理量又分为标量、矢量和张量 ,若物理量是矢量 ,它应服从矢量的加法法则 ,即两个矢量相加时 ,相加次序不影响它的结果 ,由A→ +B→ =B→+A→ 所得到的最终结果相同。根据这一原则 ,首先 ,将质点对两个坐标轴角坐标的变化等效的转化成坐标系对坐标轴的转动 ;其次 ,交换坐标系对坐标轴的转动次序 ,由此得到的同一矢量两个不同的结果表达式。结果表明 ,无限小的角位移、角速度、平均角加速度、角加速度都是矢量 ,而有限大的转角 。 展开更多
关键词 角位移 角速度 角加速度 矢量 标量性 角量
下载PDF
肾移植后生育期女性的月经、性生活及生育状况 被引量:2
2
作者 左富姐 韩澍 +4 位作者 王立明 闵敏 冯小芳 周梅生 李群 《中国组织工程研究》 CAS CSCD 2013年第5期797-804,共8页
背景:理论上讲成功的肾移植可以使生育年龄段女性月经正常化,性生活明显改善,肾移植后可以生育,但国内报道不多。目的:通过自制的"生育年龄段女性肾移植后的月经、性生活、生育状况调查表"并配合生活质量评分表、女性性功能... 背景:理论上讲成功的肾移植可以使生育年龄段女性月经正常化,性生活明显改善,肾移植后可以生育,但国内报道不多。目的:通过自制的"生育年龄段女性肾移植后的月经、性生活、生育状况调查表"并配合生活质量评分表、女性性功能指标量表调查不同生育年龄段女性肾移植前后月经、性生活及移植后生育状况,探讨其影响因素。方法:选择2006年1月至2011年12月在长征医院施行肾移植的生育年龄段患者68例,依据年龄段分为低年组(n=41)和中年组(n=27),以自制的"生育年龄段女性肾移植后的月经、性生活、生育状况调查表"并配合生活质量评分表、女性性功能指标量表进行门诊和电话随访,观察两组患者移植后3年与血液透析期的月经、性生活、生育状况,并分析其影响因素。结果与结论:54例在肾移植后(3.46±1.23)个月月经改善(低年组38例,中年组16例),11例改善不明显(低年组3例,中年组8例),3例较透析前恶化(低年组0例,中年组3例),其中因月经量过多2例行诊刮术,1例行宫腔镜止血术;45例在肾移植后(3.43±1.27)个月性生活改善(低年组34例,中年组11例),11例无明显改善(低年组2例,中年组9例),12例移植后无性生活史(低年组5例,中年组7例)。7例肾移植后(30.24±7.86)个月受孕(低年组5例,中年组2例),其中2例生育子女(均为低年组),5例流产。通过患者肾移植后及移植前进行SF-36量表的调查比较,发现受者在躯体功能、生理职能、躯体疼痛、总体健康、活力领域分值均较移植前明显升高(P<0.05),但在情感职能、心理健康及社会功能领域分值与移植前比较,差异无显著性意义(P>0.05)。肾移植后与肾移植前患者FSFI量表评分比较,发现肾移植后患者性生活质量各指标中,性欲望、性兴奋、阴道润滑、高潮、满意度分值升高,疼痛分值下降,差异均有显著性意义(P<0.05)。结果可见年龄较大受者月经、性生活状况改善也不明显,在严密监护并认真掌控受孕标准的情况下,女性肾移植受者妊娠是可行、安全的。 展开更多
关键词 器官移植 肾移植 血液透析 月经 生活 生育 健康调查表(SF-36) 功能指标量表(FSFI) 调查
下载PDF
聚焦超声治疗外阴上皮内非瘤样变及术后对性生活质量的评价 被引量:4
3
作者 李晶燕 《中国实用医药》 2012年第15期108-110,共3页
目的观察高强度聚焦超声治疗外阴上皮内非瘤样病变的临床疗效及对患者性生活质量的影响。方法选择2008年3月至2011年11月,于我院经外阴多点活检病理证实为外阴上皮内非瘤样病变者198例,随机分为超声聚焦治疗组(n=102)和药物+微波治疗组(... 目的观察高强度聚焦超声治疗外阴上皮内非瘤样病变的临床疗效及对患者性生活质量的影响。方法选择2008年3月至2011年11月,于我院经外阴多点活检病理证实为外阴上皮内非瘤样病变者198例,随机分为超声聚焦治疗组(n=102)和药物+微波治疗组(n=96)。超声组采用高强度聚焦超声连续直线扫描,治疗功率3.5W,时间20~30分,药物+微波组选用我院自制的复方白斑膏加传统微波治疗。治疗前及疗程结束6个月外阴多点活检,进行疗效评估。治疗前后分别采用女性性功能指标量表(Female Sexual Function Index,FSFI)对患者性功能进行评价。结果治疗后6个月,根据临床评分表,对病损部位皮肤弹性、色泽、病损范围占外阴部的百分比进行综合评价。超声组治愈35例(34.3%),显效63例(61.8%),无效4例(3.9%),有效率为96.1%(98/102)。药物+微波组96例,治愈5例(5.2%),显效56例(58.3%),无效35例(36.5%),有效率为63.5%(61/96)。二者比较差异有统计学意义。术后6月两组患者性生活评分有统计学差异(P<0.01)。结论聚焦超声治疗具有安全、有效、无创的特点,能有效改善患者性生活障碍。是治疗外阴上皮内非瘤样病变的有效手段。 展开更多
关键词 聚焦超声治疗 外阴上皮内非瘤样病变 疗效评价 功能指标量
下载PDF
指称转喻的回指照应机制 被引量:8
4
作者 韩丹 许宁云 《解放军外国语学院学报》 北大核心 2006年第2期6-10,共5页
在包含指称转喻关系的语句中,谓项与其论元之间的语义冲突是标量性的,冲突的大小决定了转喻关系中源域成分和靶域成分的相对突显度,语义冲突大,则靶域成分被逼显,从而倾向于被后续话语中的代词回指;语义冲突小,则源域成分因其仍处于活... 在包含指称转喻关系的语句中,谓项与其论元之间的语义冲突是标量性的,冲突的大小决定了转喻关系中源域成分和靶域成分的相对突显度,语义冲突大,则靶域成分被逼显,从而倾向于被后续话语中的代词回指;语义冲突小,则源域成分因其仍处于活跃状态并占据话题位置而跃居突显地位,从而倾向于被后续话语中的代词回指,这是指称转喻的回指照应机制。 展开更多
关键词 指称转喻 回指照应机制 语义冲突 标量性
下载PDF
腹腔镜下两种阴道成形术治疗MRKH综合征的临床研究 被引量:3
5
作者 颉丽 刘青 +2 位作者 王晓黎 龙丽霞 栾桦 《中国内镜杂志》 CSCD 北大核心 2011年第9期913-916,920,共5页
目的比较腹腔镜辅助乙状结肠阴道成形术与腹膜阴道成形术治疗36例MRKH综合征(MRKHs)的临床效果。方法 2006年4月~2010年2月对该院36例先天性无阴道患者实施腹腔镜辅助阴道成形术,其中22例实施腹腔镜辅助乙状结肠阴道成形术(乙状结肠阴... 目的比较腹腔镜辅助乙状结肠阴道成形术与腹膜阴道成形术治疗36例MRKH综合征(MRKHs)的临床效果。方法 2006年4月~2010年2月对该院36例先天性无阴道患者实施腹腔镜辅助阴道成形术,其中22例实施腹腔镜辅助乙状结肠阴道成形术(乙状结肠阴道成形术组),14例实施腹腔镜辅助腹膜阴道成形术(腹膜阴道成形术组),比较两组术中及术后的情况。结果腹腔镜腹膜阴道成形术组手术时间、术后排气时间、术后住院天数明显短于腹腔镜辅助乙状结肠阴道成形术组;术中出血量少于乙状结肠阴道成形术组;住院费用低于乙状结肠阴道成形术组;术后体温恢复时间,两组差异无显著性;人工阴道长度乙状结肠阴道成形术组长于腹膜阴道成形术组。对术后有性生活的患者采用女性性功能指标量表(FSFI)评分,两组相比差异无显著性,与正常女性比较亦差异无显著性。结论腹腔镜阴道成形术治疗MRKH综合征是微创、安全的。与腹腔镜辅助乙状结肠阴道成形术相比,腹腔镜腹膜阴道成形术具有出血少、手术时间短、住院费用低及合并症少的优势。 展开更多
关键词 MRKH综合征 腹腔镜辅助乙状结肠阴道成形术 腹腔镜辅助腹膜阴道成形术 功能指标量
下载PDF
Selection of Example Varieties Used in the DUS Test Guideline of Tagetes L. 被引量:1
6
作者 刘艳芳 张建华 +6 位作者 王烨 陈海荣 徐云 杨晓洪 张惠 管俊娇 王江民 《Agricultural Science & Technology》 CAS 2012年第10期2110-2111,2116,共3页
[Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurement... [Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurements of flower diameter of 25 varieties were collected and then analyzed by using the box plot to illustrate the uniformity and stability of flower diameter of each variety.[Result] According to the information of variability,distribution symmetry of measurements and outliers of flower diameter of varieties provided by box plots,variety 16,2 and 4 were selected as the example varieties for the three expression states with respective flower diameter of 3.0-4.4,6.0-7.4 and 9.0-10.4 cm.[Conclusion] The box plot is an efficient method for the general analysis of varieties,which provides information covering the actual and possible expression range,median and outliers of measurements of flower diameter of each variety.It also provides references for selecting example varieties for other quantitative characteristics and evaluating the quality of varieties. 展开更多
关键词 DUS Test Guideline of Tagetes L. Quantitative characteristic Example variety The box plot
下载PDF
用“分份思想”巧解能量问题
7
作者 吴国泉 《中学物理》 北大核心 2009年第7期63-64,共2页
能量问题在高中物理当中占有很大比重,而且一向是高考的重点考查内容.尤其是在客观题中往往考查的非常灵活,但是只要在平时的学习中留心抓住能的一些特点,一定能找到迅速解决问题的妙法.下面我针对能的标量性在解题中的应用谈一下... 能量问题在高中物理当中占有很大比重,而且一向是高考的重点考查内容.尤其是在客观题中往往考查的非常灵活,但是只要在平时的学习中留心抓住能的一些特点,一定能找到迅速解决问题的妙法.下面我针对能的标量性在解题中的应用谈一下我的体会,希望能起到抛砖引玉的作用. 展开更多
关键词 能量问题 高中物理 考查内容 客观题 标量性 高考 学习 解题
下载PDF
Lie Symmetries and Conserved Quantities of Holonomic Systems with Remainder Coordinates 被引量:1
8
作者 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期26-31,共6页
Aim To study the Lie symmetries and the consered quantities of the holonomic systems with remainder coordinates. Methods Using the invariance of the ordinary differential equations under the infinitesimal transformati... Aim To study the Lie symmetries and the consered quantities of the holonomic systems with remainder coordinates. Methods Using the invariance of the ordinary differential equations under the infinitesimal transformations to establish the determining equations and the restriction equations of the Lie symmetries of the systems. Results and Conclusion the structure equation and the form of conserved quantities were obtained. An example was given to illustrate the application of the result. 展开更多
关键词 analytical mechanics remainder coordinate Lie symmetry conserved quantity
下载PDF
Effects of Nitrogen Fertilizer Management on Biological Traits and Physiological Indexes at Seedling Stage and Yield of Directly-sown Rapeseed(Brassica napus L.) 被引量:1
9
作者 杨云飞 刘士山 吴永成 《Agricultural Science & Technology》 CAS 2017年第12期2401-2405,2414,共6页
Field experiments were carried out to study the effects of different nitroge- napplication rates and application times on biological traits and physiological indexes of directly-sown rapeseed (Brassica napus L.) at ... Field experiments were carried out to study the effects of different nitroge- napplication rates and application times on biological traits and physiological indexes of directly-sown rapeseed (Brassica napus L.) at the seedling stage and investigate the relationship between these biological traits or physiological indexes at the seedling stage and yield, so as to provide scientific theoretical support for high yield and efficient fertilization management in production of winter rapeseed. Field trials were conducted in Chengdu plain of Sichuan Province under rice-rapeseed rotation system during the period of 2011-2012. The nitrogen application rate trial consisted of five nitrogen levels (0, 90, 180, 270 and 360 kg/hm2) and the nitrogen application time trial included NTl(single application as base fertilized), NT2 (bottom application +one time of topdressing at seedling stage) and NT3 (bottom application+two times of topdressing at seedling stage) under the same nitrogen rate (225 kg/hm2). The results indicated that compared with no nitrogen application (NO) treatment, the in- crease of nitrogen fertilizer is beneficial to the increase of biological traits including plant height, green leaf number, leaf area index and dry weight of rapeseed at the seedling stage, the improvement of physiological indexes including total nitrogen content, chlorophyll content and soluble protein content of functional leaves, and the reduction of soluble sugar content. Nitrogen rate was linearly correlated with various biological traits at the seedling stage and physiological indexes including total nitro- gen content, chlorophyll content and soluble sugar content in functional leaves over- a/I, but in parabolic correlation with soluble protein content. Under the same nitrogen rate, NT2 treatment exhibited biological traits remarkably or significantly higher than NT1 treatment and NT3 treatment. The nitrogen application times were linearly cor- related with the physiological indexes of functional leaves at the seedling stage. The various biological traits and physiological index of functional leaves at the seedlings stage were in quadratic function parabolic correlation with seed yield, and the corre- lation was significant (P〈0.05). Therefore, under the rice-rapeseed rotation system in Chengdu plain, the economic rational nitrogen rate is 180-225 kg/hm2, and the mode of bottom application + one time of topdressing (NT2) is suitable. 展开更多
关键词 Winter rapeseed (Brassica napus L.) Direct seeding Nitrogen fertilizermanaaement Bioloqical traits Physioloqical index YIELD
下载PDF
“恒定电流”五项注意
10
作者 何建东 《中学生数理化(高二数学、高考数学)》 2014年第7期44-45,共2页
在“恒定电流”的学习中,下列五个方面值得同学们高度重视.这五个方面,有些是对物理量和物理规律的理解存在的疑惑,有些是对公式和图像的随意应用引起的错误,还有些是对电学实验方面存在的粗浅甚至错误的认识.一、对电流是标量的理解电... 在“恒定电流”的学习中,下列五个方面值得同学们高度重视.这五个方面,有些是对物理量和物理规律的理解存在的疑惑,有些是对公式和图像的随意应用引起的错误,还有些是对电学实验方面存在的粗浅甚至错误的认识.一、对电流是标量的理解电流有方向,那么电流究竟是标量还是矢量?这个问题时时困扰着我们.要理解其标量性,应从其作用效果方面入手.在一段电路中,无论电流的方向如何,电流引起的热效应是相同的.所以电流是标量,而不是矢量. 展开更多
关键词 恒定电流 标量性 物理规律 电学实验 物理量 热效应 矢量 学习
下载PDF
Full tensor gravity gradiometry data inversion:Performance analysis of parallel computing algorithms 被引量:2
11
作者 侯振隆 魏晓辉 +1 位作者 黄大年 孙煦 《Applied Geophysics》 SCIE CSCD 2015年第3期292-302,465,共12页
We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine M... We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine MPI with CUDA to formulate a hybrid algorithm. Parallel computing performance metrics are introduced to analyze and compare the performance of the algorithms. We summarize the rules for the performance evaluation of parallel algorithms. We use model and real data from the Vinton salt dome to test the algorithms. We find good match between model efficiency and feasibility of parallel computing gravity gradiometry data. and real density data, and verify the high algorithms in the inversion of full tensor 展开更多
关键词 MPI CUDA performance metrics full tensor gravity gradiometry density inversion
下载PDF
MICROTHREAD BASED (MTB) COARSE GRAINED FAULT TOLERANCE SUPERSCALAR PROCESSOR ARCHITECTURE 被引量:3
12
作者 Fu Zhongchuan Chen Hongsong Cui Gang 《Journal of Electronics(China)》 2006年第3期461-466,共6页
Fault tolerance in microprocessor systems has become a popular topic of architecture research. Much work has been done at different levels to accomplish reliability against soft errors, and some fault tolerance archit... Fault tolerance in microprocessor systems has become a popular topic of architecture research. Much work has been done at different levels to accomplish reliability against soft errors, and some fault tolerance architectures have been proposed. But little attention is paid to the thread level superscalar fault tolerance. This letter introduces microthread concept into superscalar processor fault tolerance domain, and puts forward a novel fault tolerance architecture, namely, MicroThread Based (MTB) coarse grained transient fault tolerance superscalar processor architecture, then discusses some detailed implementations. 展开更多
关键词 Microthread Basic block Coarse grained fault tolerance Superscalar processor
下载PDF
Effects of Interaction Between Gravitation and Nonlinear Electrodynamics On Scalar Field Evolution 被引量:1
13
作者 陈菊华 王永久 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期813-816,共4页
In this paper we investigate the scalar field evolution in the dyadosphere spacetime by using the third-order WKB approximation. We find that the coupling term between the gravitation and the nonlinear electrodynamics... In this paper we investigate the scalar field evolution in the dyadosphere spacetime by using the third-order WKB approximation. We find that the coupling term between the gravitation and the nonlinear electrodynamics makes the scalar field decay more quickly and it also makes the scalar field oscillate more slowly. On the o'ther words, this coupling term takes effect on the scalar field evolution as a damping factor. At the same time these effects become more obvious for the scalar field with higher angle quantum number. 展开更多
关键词 scalar field nonlinear electrodynamics dyadosphere spacetime
下载PDF
Research on Radar Emitter Attribute Recognition Method 被引量:1
14
作者 GUAN Xin YI Xiao HE You 《Geo-Spatial Information Science》 2006年第1期45-48,共4页
In order to solve emitter recognition problems in a practical reconnaissance environment, attribute mathematics is introduced. The basic concepts and theory of attribute set and attribute measure are described i n det... In order to solve emitter recognition problems in a practical reconnaissance environment, attribute mathematics is introduced. The basic concepts and theory of attribute set and attribute measure are described i n detail. A new attribute recognition method based on attribute measure is prese nted in this paper. Application example is given, which demonstrates this new me thod is accurate and effective. Moreover, computer simulation for recognizing th e emitter purpose is selected, and compared with classical statistical pattern r ecognition through simulation. The excellent experimental results demonstrate t hat this is a brand-new attribute recognition method as compared to existing st atistical pattern recognition techniques. 展开更多
关键词 attribute measure attribute recognition criterion emitter recognition
下载PDF
Decay of Solutions of Non convex Scalar Conservation Laws
15
作者 潘君 郭秋丽 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期6-11,共6页
We study the large time behavior of solutions of scalar conservation laws with periodic initial data. Under a very weak nonlinearity condition,we prove that the solutions converge to constants as time tends to infinit... We study the large time behavior of solutions of scalar conservation laws with periodic initial data. Under a very weak nonlinearity condition,we prove that the solutions converge to constants as time tends to infinity. Our results improve the earlier ones since we only require the flux to be nonlinear at the mean value of the initial data. 展开更多
关键词 non convex conservation laws asymptotic behavior
下载PDF
Supersymmetry and Solution of Dirac Equation with Vector and Scalar Potentials
16
作者 JU Guo-Xing REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期319-326,共8页
The Dirac equations with vector and scalar potentials of the Coulomb types in two and three dimensions are solved using the supersymmetric quantum mechanics method. For the system of such potentials, the analytical ex... The Dirac equations with vector and scalar potentials of the Coulomb types in two and three dimensions are solved using the supersymmetric quantum mechanics method. For the system of such potentials, the analytical expressions of the matrix dements for both position and momentum operators are obtained. 展开更多
关键词 Dirac equation vector potential scalar potential SUPERSYMMETRY matrix element
下载PDF
A new method of characterizing equivalent strain for equal channel angular processing 被引量:1
17
作者 赵军 王振华 +3 位作者 孙淑华 赵德利 任利国 傅万堂 《Journal of Central South University》 SCIE EI CAS 2009年第3期349-353,共5页
In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new ... In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new approach to characterize the equivalent strain was proposed. The results show that there exists better accordance between mechanical property (such as hardness or strength) and equivalent strain after rolling and ECAP in a certain range of deformation amount, and Gauss equation can be satisfied among the equivalent strain and the mechanical properties for ECAP. Through regression analysis on the data of hardness and strength after the deformation, a more generalized expression of equivalent strain for ECAP is proposed as:ε=k0exp[-(k1M-k2)^2], where M is the strength or hardness of the material, k1 is the modified coefficient (k1∈ (0, 1)), ko and k2 are two parameters dependent on the critical strain and mechanical property that reaches saturation state for the material, respectively. In this expression the equivalent strain for ECAP is characterized novelly through the mechanical parameter relating to material property rather than the classical geometry equation. 展开更多
关键词 equal channel angular processing (ECAP) equivalent strain mechanical property characterizing method
下载PDF
Research of Software Complexity Metrics with Security Indicator
18
作者 付剑晶 王珂 《Journal of Donghua University(English Edition)》 EI CAS 2011年第5期460-464,共5页
Software protection technology has been universally emphasized, with the development of reverse engineering and static analysis techniques. So, it is important to research how to quantitatively evaluate the security o... Software protection technology has been universally emphasized, with the development of reverse engineering and static analysis techniques. So, it is important to research how to quantitatively evaluate the security of the protected software. However, there are some researchers evaluating the security of the proposed protect techniques directly by the traditional complexity metrics, which is not suffident. In order to better reflect security from software complexity, a multi-factor complexity metric based on control flow graph (CFG) is proposed, and the corresponding calculating procedures are presented in detail. Moreover, complexity density models are constructed to indicate the strength of software resisting reverse engineering and code analysis. Instance analysis shows that the proposed method is simple and practical, and can more objectively reflect software security from the perspective of the complexity. 展开更多
关键词 complexity metric software protection complexity density control flow graph
下载PDF
Some Topological Properties of Anyons
19
作者 CAO Zhen-Bin LIU Yu-Xiao DUAN Yi-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1155-1158,共4页
In this paper,starting with the well known U(1)Chern-Simons Lagrangian and the covariant derivative ofa complex scalar matter field,we give a detailed discussion of some topological properties of anyons.We show that t... In this paper,starting with the well known U(1)Chern-Simons Lagrangian and the covariant derivative ofa complex scalar matter field,we give a detailed discussion of some topological properties of anyons.We show that the'basic'charge carried by anyons has an inner structure and can be decomposed in terms of the Chern-Simons couplingand the gauge coupling constants of the theory.Also some incorrect results obtained in the literature are revised. 展开更多
关键词 ANYON complex scalar held
下载PDF
Detecting white matter alterations in multiple sclerosis using advanced diffusion magnetic resonance imaging 被引量:1
20
作者 Sourajit M.Mustafi Jaroslaw Harezlak +4 位作者 Chandana Kodiweera Jennifer S.Randolph James C.Ford Heather A.Wishart Yu-Chien Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第1期114-123,共10页
Multiple sclerosis is a neurodegenerative and inflammatory disease, a hallmark of which is demyelinating lesions in the white matter. We hypothesized that alterations in white matter microstructures can be non-invasiv... Multiple sclerosis is a neurodegenerative and inflammatory disease, a hallmark of which is demyelinating lesions in the white matter. We hypothesized that alterations in white matter microstructures can be non-invasively characterized by advanced diffusion magnetic resonance imaging. Seven diffusion metrics were extracted from hybrid diffusion imaging acquisitions via classic diffusion tensor imaging, neurite orientation dispersion and density imaging, and q-space imaging. We investigated the sensitivity of the diffusion metrics in 36 sets of regions of interest in the brain white matter of six female patients(age 52.8 ± 4.3 years) with multiple sclerosis. Each region of interest set included a conventional T2-defined lesion, a matched perilesion area, and normal-appearing white matter. Six patients with multiple sclerosis(n = 5) or clinically isolated syndrome(n = 1) at a mild to moderate disability level were recruited. The patients exhibited microstructural alterations from normal-appearing white matter transitioning to perilesion areas and lesions, consistent with decreased tissue restriction, decreased axonal density, and increased classic diffusion tensor imaging diffusivity. The findings suggest that diffusion compartment modeling and q-spa ce analysis appeared to be sensitive for detecting subtle microstructural alterations between perilesion areas and normal-appearing white matter. 展开更多
关键词 multiple sclerosis hybrid diffusion imaging NODDI diffusion tensor imaging q-space imaging
下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部