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1.
目的 应用静息态fMRI数据检验轻度认知功能障碍(MCI)患者大脑功能网络是否具有小世界特性。方法 采集13例MCI患者(MCI组)和17名正常老年人(NC组)的大脑静息态BOLD-fMRI数据。采用SPM 5软件对图像进行预处理,将大脑分割为90个区域并计算90个区域间的相关系数。以矩阵稀疏度(Sparsity)为阈值,将相关矩阵转换为网络。计算网络的聚类系数(C)和平均路径长度(L),若满足γ=C/Crand>1且λ= L/Lrand ≈1(rand代表相应随机网络),为该大脑功能网络具有小世界特性。采用双样本t检验比较MCI组与NC组大脑功能网络小世界参数的差异。结果 在0.1~0.4阈值范围内,MCI组和NC组均符合γ>1且λ≈ 1。MCI组γ和δ均大于NC组,且在0.10≤Sparsity≤0.18时差异具有统计学意义(P<0.05);MCI组λ在各阈值处均小于NC组,在Sparsity=0.18、0.28和0.32处差异具有统计学意义(P<0.05)。结论 MCI患者大脑fMRI网络具有小世界特性,但与正常老年人相比其小世界特性增强。  相似文献   

2.
目的 采用静息态功能MRI (fMRI)功能连接分析技术,观察全面强直阵挛癫痫患者发作间期静息态脑网络的改变,探讨强直阵挛癫痫的病理生理机制.方法 52例全面强直阵挛癫痫患者与57名止常志愿者(对照组)参与了,本研究.采集闭眼静息态fMRI数据.分别以双侧丘脑,双侧后扣带皮质为种子点,观察丘脑网络、默认网络(DMN)在患者中的功能改变.结果 组内单样本t检验结果提示,以双侧丘脑为种子点的功能连接模式主要分布于额顶叶,而以双侧后扣带皮质为种子点的功能连接模式主要表现为默认网络.进一步组间比较发现,患者的丘脑与双侧运动皮层及右侧岛叶的功能连接增强,而与DMN脑区及基底节的功能连接减弱;而DMN内部与后扣带皮质的功能连接在双侧颞极、内侧前额叶和缘上回的功能连接减弱,而与双侧角回、丘脑和左侧额上回的功能连接增强.结论 丘脑是强直阵挛癫痫网络的重要节点,它与运动皮层间增强的功能连接可能与癫痫发作时患者肌肉的强直阵挛有关.而默认网络内功能连接的异常可能与癫痫发作时的意识丧失有关.即使在发作间期,全面强直阵挛癫痫的脑功能也有着显著改变.  相似文献   

3.
功能磁共振成像评价帕金森患者静息状态下脑功能连接   总被引:3,自引:1,他引:2  
目的 采用功能磁共振成像(fMRI)评价帕金森病(PD)患者静息状态下脑功能连接的特点. 方法 对14例符合PD诊断标准的患者及14名健康者行静息态脑fMRI,选双侧壳核为感兴趣区,PD患者与正常对照组间脑功能连接的差异用随机效应两样本t检验.结果 与正常对照组相比,PD患者在静息状态下前额叶中内侧、双侧尾状核头部、左侧脑岛、左侧梭状回等脑区功能连接减低;双侧小脑半球、双侧舌回、双侧颞中回、右中央前回、右侧额上回、右侧额下回、右侧扣带回后部、左侧额中回等脑区功能连接增强.结论 PD患者在静息状态下存在异常的脑功能连接网络.  相似文献   

4.
摘要 目的:应用功能性近红外光谱技术(functional near-infrared spectroscopy, fNIRS)研究帕金森病(Parkinson''s disease, PD)患者在静息态及平板步行训练中脑功能网络的改变。 方法:本研究纳入PD患者10例作为试验组(PD组),同时招募健康对照(Healthy controls,HC)10例(HC组)。分别采集两组受试者在静息态和平板步行训练时的fNIRS数据,通过计算脑功能网络拓扑属性以评估PD组和HC组的两种全局指标:小世界参数,包括集群系数(clustering coefficient, Cp)、最短路径长度(shortest path length, Lp)和小世界属性(small world properties, σ);网络效率参数,包括全局效率(global efficiency, Eg)和局部效率(local efficiency, Eloc)。 结果:①PD组和HC组的σ值均大于1,符合小世界网络的特征且两者之间无显著性差异(P>0.05)。②静息态下,PD组的Cp,Lp和Eloc显著低于HC组(P=0.0124,0.0475,0.0381),但PD组的Eg显著增强(P=0.0330)。③平板步行训练中,PD组的Lp较HC组降低(P=0.0193),Eg较HC组增强(P=0.0483),两组间的Cp和Eloc无显著性差异(P>0.05)。 结论:PD患者存在皮层连接的过度增强,脑网络功能分离与整合之间的平衡被扰乱。平板步行训练可能通过调节局部脑网络之间的连通性,改善其脑功能,从而促进PD患者的康复。  相似文献   

5.
目的 探讨自闭症谱系障碍(autism spectrum disorder,ASD)儿童与正常发育(typically developing,TD)儿童的脑功能网络拓扑结构差异。材料与方法 从国际自闭症脑成像交换数据库的4个站点中提取符合纳入标准的65例ASD儿童(ASD组)及65例TD儿童(TD组)的脑部静息态功能磁共振成像及T1加权结构像数据。应用图论分析研究大脑网络的拓扑结构,包括全局和局部拓扑参数。结果 在阈值范围内,ASD在聚类系数(clustering coefficient,Cp)和特征路径长度(characteristic path length,Lp)低于TD组(P<0.05);两组在全局效率(global efficiency,Eglob)、局部效率(local efficiency,Eloc)等指标的差异无统计学意义。ASD组和TD组的脑功能连接网络满足标准化的聚类系数(γ)>1和标准化的特征路径长度(λ)≈1,具有小世界网络属性,但两组间的γ和λ值差异无统计学意义。节点水平分析结果显示ASD组在双侧前扣带回、双侧尾状核、双侧海马、右侧顶下小叶等脑区的...  相似文献   

6.
摘要 目的:基于静息态功能磁共振成像(functional magnetic resonance imaging, fMRI)研究慢性期左侧皮层下脑卒中后轻中度手功能障碍(部分偏瘫手)患者运动功能网络的重组模式。 方法:招募32例脑卒中后部分偏瘫手患者和40例匹配的健康老年对照。采集两组受试者的静息态fMRI数据,并采用Fugl-Meyer腕手运动功能量表评定患者的手功能障碍程度。采用RESTplus软件分析双侧初级运动皮层(primary motor cortex,M1)与全脑功能连接(functional connectivity,FC)的组间差异,并采用Pearson相关分析探究患者的FC模式与手功能评分之间的关系。 结果:与健康老年对照相比,部分偏瘫手患者的患侧M1区与健侧感觉运动区、患侧海马和患侧颞中回的FC减弱,并且健侧M1区与患侧中央后回、健侧顶下小叶、患侧颞上回和患侧脑岛的FC也减弱。相关性分析发现,部分偏瘫手患者的健侧M1区与辅助运动区的FC强度与手功能评分正相关(r=0.67, P<0.001)。 结论:慢性期左侧皮层下脑卒中后部分偏瘫手患者的运动功能网络发生了广泛的失连接重组,其中,健侧M1区与辅助运动区之间增强的FC可能是提示良好手功能结局的神经影像标记物。  相似文献   

7.
目的:分析颞叶癫痫患者静息态磁共振(rest-f MRI)功能连接及其与记忆功能之间的关系,探讨其脑功能连接的异常及其对记忆障碍诊治的应用价值。方法:对16例颞叶癫痫患者(癫痫组)和与之相匹配的16例健康对照者(对照组)进行静息态脑功能成像和记忆功能测评,比较2组间的脑区差异,分析与记忆功能相关的脑区。结果:癫痫组与对照组比较,海马与全脑功能连接增高的脑区有:左侧旁中央小叶、左侧中央前回、左侧中央后回、左侧前运动皮质和辅助运动区、左侧内侧额叶等;减低的脑区有:右侧小脑、左侧颞上回等。癫痫组海马与全脑功能连接与记忆商呈正相关的脑区有:双侧前扣带回、双侧楔前叶/后扣带回等;呈负相关的脑区有:左侧额下回、左侧中央后回等。结论:左侧旁中央小叶、左侧中央前回、左侧中央后回、左侧前运动皮质和辅助运动区、左侧内侧额叶等脑区可能构成颞叶癫痫患者的癫痫网络,在癫痫发生和发展过程中起重要作用;右侧小脑、左侧颞上回等脑区的功能异常可能与颞叶癫痫患者认知功能损伤有关。双侧前扣带回、双侧楔前叶/后扣带回、左侧额下回、左侧中央后回等脑区与海马之间的功能连接与记忆相关,其对记忆功能具有潜在临床预测价值。  相似文献   

8.
MRI观察精神分裂症静息态下小脑功能连接和解剖连接   总被引:1,自引:0,他引:1  
目的 应用静息态功能磁共振成像(fMRI)和扩散张量成像(DTI)观察精神分裂症患者与正常人小脑功能连接与解剖连接的差异。方法 分别对10例精神分裂症患者(精神分裂组)及14名健康对照者(正常对照组)行静息态脑fMRI和DTI。对数据进行后处理后得到功能连接的相关系数r值及小脑中脚的平均FA值,应用双样本t检验比较组间差异,并对两种数据进行相关性检验。结果 ①精神分裂组与左侧小脑功能连接改变显著的区域为双侧舌回、右侧额中回、双侧缘上回和左侧小脑(P<0.001,未校正);与右侧小脑功能连接改变显著的区域为双侧舌回、左侧中央前回和左侧缘上回(P<0.001,未校正);②精神分裂组左侧小脑中脚的FA值显著降低(P<0.05);③精神分裂组右侧小脑-右侧舌回的连接强度与右侧小脑中脚的FA值呈显著正相关(r=0.84,P<0.05)。结论 联合运用多种成像方式可能为理解小脑在精神分裂症病理生理学中的作用提供新的方向;精神分裂症患者静息态下小脑与大脑皮层某些区域的连接降低和小脑中脚局部白质纤维完整性受损的同时出现以及二者之间的相关性提示功能连接与解剖解剖之间存在密切关系。  相似文献   

9.
静息态功能磁共振成像观察正常人听觉皮层功能   总被引:1,自引:1,他引:0  
目的 探讨正常人听觉皮层与全脑的正相关及负相关的功能连接.方法 采用静息态下平面回波成像技术采集44名健康受试者fMRI数据,分别以左侧及右侧AⅠ区为种子点,用功能连接的方法观察左、右大脑初级听觉皮层与全脑的正相关及负相关功能连接脑图.结果 分别以双侧AⅠ区为种子点时,正激活的脑网络主要包含双侧AⅠ、AⅡ、岛叶、辅助运动区及扣带回,以同侧为主;与右侧AⅠ区相关的正激活脑区还包括同侧背侧丘脑.与双侧AⅠ区相关的负激活脑网络与脑默认网络大体一致,主要包括双侧后扣带回/楔前叶、额叶内侧回、顶下小叶,双侧小脑半球可见明显激活.结论 静息态磁共振功能连接可满意显示听觉皮层的连接脑图.正相关功能连接主要局限在听觉系统内,负相关功能连接类似于默认网络.  相似文献   

10.
目的分析一氧化碳中毒迟发性脑病患者(delayed encephalopathy after acute carbon monoxide poisoning,DEACMP)静息状态下默认脑网络改变特征,探讨磁共振在一氧化碳中毒迟发性脑病患者的认知损伤评估应用及研究价值。材料与方法采集22例DEACMP患者和22例年龄、性别、受教育年限相匹配健康对照组的fMRI数据,应用独立成分分析(independent component,ICA)法分离静息态脑网络成分并进行统计学分析,首先用单样本t检验制作网络成分模板,再运用两独立样本双侧t检验进行组间功能网络内异常脑区的比较,采用24项汉密尔顿抑郁量表(24-item Hamilton Rating Scale for depression,HAMD-24)、汉密尔顿焦虑量表(Hamilton Anxiety Rating Scale,HAMA)、简易精神状态评价量表(Mini-mental State Examination,MMSE)等评估临床症状。结果通过DEACMP与健康对照组数据分析获得静息态默认脑网络模板,静息态默认脑网络功能连接分析结果显示双侧额上回、双侧楔叶及左侧顶叶角回功能连接增强。结论一氧化碳中毒迟发性脑病患者存在静息状态下默认脑网络异常,主要表现为功能连接的增强;DEACMP患者脑内可能存在一定的认知功能代偿。  相似文献   

11.
This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.  相似文献   

12.
目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高<20%视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P<0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P<0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P<0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.  相似文献   

13.
The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.  相似文献   

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Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.  相似文献   

16.
17.
Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.  相似文献   

18.
目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4%(55/72)]明显高于成功组[31.7%(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3%(42/72)]高于成功组[38.1% (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9% (28/72)]高于成功组[23.8%(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大<6 cm、胎头位于坐骨棘上及宫口开大8~10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1%(44/72)]高于成功组[38.9%(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2%(52/72)]明显高于成功组[34.1 %(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.  相似文献   

19.
ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.  相似文献   

20.
ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.  相似文献   

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