共查询到15条相似文献,搜索用时 0 毫秒
1.
Moeller F Siebner HR Wolff S Muhle H Boor R Granert O Jansen O Stephani U Siniatchkin M 《NeuroImage》2008,39(4):1839-1849
The pathophysiology of generalized spike wave discharges (GSW) is not completely understood. Thalamus, basal ganglia and neocortex have been implicated in the generation of GSW, yet the specific role of each structure remains to be clarified. In six children with idiopathic generalized epilepsy (IGE), we performed combined EEG-fMRI to identify GSW-related changes in blood oxygen level-dependent (BOLD) signal in the striato-thalamo-cortical network. In all patients, within-subject analysis demonstrated BOLD signal changes that preceded the GSW. An increase in BOLD signal in the medial thalamus started 6 s before the onset of the GSW. Decreases in cortical BOLD signal were mainly found in frontoparietal areas and precuneus starting 6 to 3 s before the GSW. All patients showed a decrease in BOLD signal in the head of the caudate nucleus with a variable onset. The temporospatial pattern of BOLD signal changes suggests that GSW on the cortical surface is preceded by a sequence of neuronal events in the thalamo-cortical-striatal network. Approximately 6 s before the GSW, the thalamus shows an increase in neuronal activity along with regional decreases in cortical activity. These changes in thalamo-cortical activity are followed by a deactivation of the caudate nucleus. These early changes in BOLD signal may reflect changes in neuronal activity that contribute to the generation of GSW and may contribute to the transition from a normal to a generalized hypersynchronous pattern of neuronal activity. Our preliminary findings warrant further studies on a larger number of patients to explore the influence of age, medication and type of epileptic syndrome. 相似文献
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We present a novel approach to assess the networks involved in the generation of spontaneous pathological brain activity based on multi-modal imaging data. We propose to use probabilistic fMRI-constrained EEG source reconstruction as a complement to EEG-correlated fMRI analysis to disambiguate between networks that co-occur at the fMRI time resolution. The method is based on Bayesian model comparison, where the different models correspond to different combinations of fMRI-activated (or deactivated) cortical clusters. By computing the model evidence (or marginal likelihood) of each and every candidate source space partition, we can infer the most probable set of fMRI regions that has generated a given EEG scalp data window. We illustrate the method using EEG-correlated fMRI data acquired in a patient with ictal generalized spike–wave (GSW) discharges, to examine whether different networks are involved in the generation of the spike and the wave components, respectively. To this effect, we compared a family of 128 EEG source models, based on the combinations of seven regions haemodynamically involved (deactivated) during a prolonged ictal GSW discharge, namely: bilateral precuneus, bilateral medial frontal gyrus, bilateral middle temporal gyrus, and right cuneus. Bayesian model comparison has revealed the most likely model associated with the spike component to consist of a prefrontal region and bilateral temporal–parietal regions and the most likely model associated with the wave component to comprise the same temporal–parietal regions only. The result supports the hypothesis of different neurophysiological mechanisms underlying the generation of the spike versus wave components of GSW discharges. 相似文献
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Background To correlate the dynamic computed tomography (CT) of hepatic focal nodular hyperplasia (FNH) with its size and pathology.
Methods The clinical data, pathological and dynamic CT findings of 36 FNHs in 24 males and 27 lesions in 22 females were reviewed.
The pathological and CT findings of the 32 small FNHs (diameter < 3 cm) and 31 large FNHs (diameter ≥ 3 cm) were compared
and analyzed.
Results All FNHs were hypervascular at arterial phase except for central scarring. The mean diameter of FNHs with hypoattenuating,
isoattenuating, hyperattenuating on delayed scans were 5.05 cm, 3.06 cm, and 2.70 cm, respectively (p = 0.026). As compared with small FNHs, large ones were significantly more likely to reveal central scarring (p = 0.005), vascular displacement (p < 0.001), and abnormal vessels around lesions (p < 0001). Coexistent bile ductile proliferation and bridging septa were more commonly observed in small FNHs (p = 0.028 for both). FNHs without aberrant vessels tended to feature hyperattenuating during the portal venous phase (p = 0.041).
Conclusions FNHs with different tumor sizes may manifest various dynamic CT findings that are more or less related to the different pathological
findings. 相似文献
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Byl NN Nagajaran S McKenzie AL 《Archives of physical medicine and rehabilitation》2003,84(10):1505-1514
OBJECTIVE: To measure the effects of sensorimotor training based on the principles of neuroplasticity for patients with focal hand dystonia. DESIGN: Case series of 3 subjects with focal hand dystonia of the left hand, compared with age-matched normative controls. SETTING: Outpatient clinic. PARTICIPANTS: Three consecutive clinic patients-musicians with focal hand dystonia-who described a history of repetitive practice and performance (2 women; ages, 23 y and 35 y; 1 man; age, 24 y). INTERVENTION: Subjects were asked to stop performing the tasks that caused the abnormal movements, to participate in a wellness program (aerobics, postural exercises, stress free hand use), and to carry out supervised, attended, individualized, repetitive sensorimotor training activities at least once week for 12 weeks and reinforced daily at home. MAIN OUTCOME MEASURES: Standard tests documenting somatosensory hand representation, target-specific hand control, and clinical function. RESULTS: On the affected side, the 3 subjects improved an average of 86.8% on somatosensory hand representation, 117% on target-specific performance, 23.9% on fine motor skills, 22.7% on sensory discrimination, 31.9% on musculoskeletal skills, and 32.3% on independence. All 3 subjects improved 10% or more on 90% of the subtests with 20% improvement on 50% of the subtests. CONCLUSION: Individuals with focal hand dystonia who have a history of repetitive hand use can improve cortical somatosensory responses and clinical motor function after individualized sensorimotor training consistent with the principles of neural adaptation. 相似文献
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Hiroyuki Sugimoto Tetsuya Kaneko Fjsum Tsuyoshi Hatsuno Shin Takeda Soichiro Inoue Akimasa Nakao 《Journal of Medical Ultrasonics》2002,29(3):91-97
Background We attempted to identify the physiologic circumstances associated with the portal Doppler waveform.
Method The subjects were 98 patients: 42 had cirrhosis; 23, hepatitis; and 33, no liver disorder. We measured right portal venous
peak velocity, minimum velocity, and hepatic arterial peak systolic velocity. Portal venous pulsatility was calculated as
portal venous minimum velocity divided by portal venous peak velocity. We analyzed portal waveforms both qualitatively and
quantitatively.
Results Portal Doppler waveforms were classified as nonphasic, monophasic, biphasic, biphasic including spike wave, and triphasic.
Portal waveforms were phasic in 84 subjects who had a mild systolic dip during the arterial systolic period. Markedly portal
pulsatility (portal venous pulsatility<0.6) was present in only 7 subjects. A systolic spike wave corresponding to a hepatic
arterial peak systolic wave was detected in 48 subjects. Hepatic arterial peak systolic velocity was significantly higher
in the group with spike wave than in the group without it.
Conclusion Although portal pulsatility is generally attributed to multiple factors, the present study has pointed out a new factor; transmission
via the hepatic artery through the portal vein vasa vasorum. Hepatic venous drainage and hepatic arterial blood flow influence
portal waveform. 相似文献
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There are formidable problems in studying how 'real' music engages the brain over wide ranges of temporal scales extending from milliseconds to a lifetime. In this work, we recorded the magnetoencephalographic signal while subjects listened to music as it unfolded over long periods of time (seconds), and we developed and applied methods to correlate the time course of the regional brain activations with the dynamic aspects of the musical sound. We showed that frontal areas generally respond with slow time constants to the music, reflecting their more integrative mode; motor-related areas showed transient-mode responses to fine temporal scale structures of the sound. The study combined novel analysis techniques designed to capture and quantify fine temporal sequencing from the authentic musical piece (characterized by a clearly defined rhythm and melodic structure) with the extraction of relevant features from the dynamics of the regional brain activations. The results demonstrated that activity in motor-related structures, specifically in lateral premotor areas, supplementary motor areas, and somatomotor areas, correlated with measures of rhythmicity derived from the music. These correlations showed distinct laterality depending on how the musical performance deviated from the strict tempo of the music score, that is, depending on the musical expression. 相似文献
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Keep it simple: a case for using classical minimum norm estimation in the analysis of EEG and MEG data 总被引:5,自引:0,他引:5
Hauk O 《NeuroImage》2004,21(4):1612-1621
The present study aims at finding the optimal inverse solution for the bioelectromagnetic inverse problem in the absence of reliable a priori information about the generating sources. Three approaches to tackle this problem are compared theoretically: the maximum-likelihood approach, the minimum norm approach, and the resolution optimization approach. It is shown that in all three of these frameworks, it is possible to make use of the same kind of a priori information if available, and the same solutions are obtained if the same a priori information is implemented. In particular, they all yield the minimum norm pseudoinverse (MNP) in the complete absence of such information. This indicates that the properties of the MNP, and in particular, its limitations like the inability to localize sources in depth, are not specific to this method but are fundamental limitations of the recording modalities. The minimum norm solution provides the amount of information that is actually present in the data themselves, and is therefore optimally suited to investigate the general resolution and accuracy limits of EEG and MEG measurement configurations. Furthermore, this strongly suggests that the classical minimum norm solution is a valuable method whenever no reliable a priori information about source generators is available, that is, when complex cognitive tasks are employed or when very noisy data (e.g., single-trial data) are analyzed. For that purpose, an efficient and practical implementation of this method will be suggested and illustrated with simulations using a realistic head geometry. 相似文献
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目的对比分析剪切波弹性成像与动态对比增强MRI(DCE-MRI)鉴别诊断颈部良恶性淋巴结的价值。方法选取我院收治的淋巴结肿大患者86例,根据病理结果分为良性组32例(112枚淋巴结)和恶性组54例(184枚淋巴结),均行剪切波弹性成像和DCE-MRI检查,比较两组剪切波弹性成像参数[淋巴结与周围脂肪组织弹性值比值(E-ratio)、平均弹性值(E-mean)、最大弹性值(E-max)]和DCE-MRI定量参数[容量转移常数(Ktrans)、速率常数(Kep)及血管外细胞外间隙容积比(Ve)]。绘制受试者工作特征(ROC)曲线分析并比较剪切波弹性成像参数与DCE-MRI定量参数对颈部恶性淋巴结的诊断效能。结果与良性组比较,恶性组E-ratio、E-mean、E-max均增高,差异均有统计学意义(均P<0.05)。与良性组比较,恶性组Kep增高,Ve降低,差异均有统计学意义(均P<0.05);两组Ktrans比较差异无统计学意义。ROC曲线分析显示,E-ratio、E-mean、E-max及其联合应用诊断颈部恶性淋巴结的曲线下面积分别为0.841、0.859、0.846、0.881,Kep、Ve及其联合应用诊断颈部恶性淋巴结的曲线下面积分别为0.742、0.776、0.926。当截断值为0.573,剪切波弹性成像三项参数联合应用的诊断敏感性、特异性分别为89.7%、88.4%;当截断值为0.663时,DCE-MRI两项参数联合应用的诊断敏感性、特异性分别为91.5%、88.4%。结论剪切波弹性成像与DCE-MRI定量参数对颈部良恶性淋巴结均有较高诊断价值;剪切波弹性成像参数单独应用价值更高,DCE-MRI定量参数联合应用价值更高。 相似文献
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Yvonne C. Learmonth 《Disability and rehabilitation》2016,38(13):1227-1242
Purpose: This systematic review was conducted to provide rich and deep evidence of the perceived determinants and consequences of physical activity and exercise based on qualitative research in multiple sclerosis (MS). Method: Electronic databases and article reference lists were searched to identify qualitative studies of physical activity and exercise in MS. Studies were included if they were written in English and examined consequences/determinants of physical activity in persons with MS. Content analysis of perceived determinants and consequences of physical activity and exercise was undertaken using an inductive analysis guided by the Physical Activity for people with Disabilities framework and Social Cognitive Theory, respectively. Results: Nineteen articles were reviewed. The most commonly identified perceived barriers of physical activity and exercise were related to the environmental (i.e. minimal or no disabled facilities, and minimal or conflicting advice from healthcare professionals) and related to personal barriers (i.e. fatigue, and fear and apprehension). The most commonly identified perceived facilitators of physical activity were related to the environment (i.e. the type of exercise modality and peer support) and related to personal facilitators (i.e. appropriate exercise and feelings of accomplishment). The most commonly identified perceived beneficial consequences of physical activity and exercise were maintaining physical functions, increased social participation and feelings of self-management and control. The most commonly identified perceived adverse consequences were increased fatigue and feelings of frustration and lost control. Conclusions: Results will inform future research on the perceived determinants and consequences of physical activity and exercise in those with MS and can be adopted for developing professional education and interventions for physical activity and exercise in MS.
- Implications for Rehabilitation
Physical activity and exercise behaviour in people with multiple sclerosis (MS) is subject to a number of modifiable determinants.
Healthcare professionals working to promote physical activity and exercise in those with MS should choose to endorse the positive benefits of participation.
Future physical activity interventions for those with MS may be improved by incorporating behavioural management strategies.
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目的 运用世界卫生组织(WHO)健康服务6大构成要素理论,对康复体育的政策架构、核心内容以及优先领域进行内容分析,从宏观、中观和微观3个层次,探讨康复体育的政策架构、行动战略以及实施方法。方法 依据WHO发布的《健康服务体系中的康复》和《健康服务体系中的康复:行动指南》,结合其配套使用工具等政策文件,运用内容分析方法,探讨康复体育服务体系的政策架构以及行动战略、核心内容与优先发展领域。结果 康复体育是现代康复的组成部分,依据《国际功能、残疾与健康分类》的功能、残疾和健康理论,秉持以人为本的理念,采取措施满足残疾人康复体育服务需求,整合于健康服务连续体之中,促进实现全民健康覆盖的可持续发展目标。康复体育服务发展涉及领导力和治理、筹资、人力资源、服务提供、设备/技术/设施和监测评估与信息系统6大领域。在康复体育法规、政策与治理领域,国家为发展康复体育制定法律法规、政策文件、行动指南等,提升政府领导力与治理;拓宽康复体育筹资渠道并优化经费分配方案;完善康复体育人才培养体系,将康复体育专业人员匹配到三级卫生健康服务机构中,确保有康复体育需求的功能障碍者能够在不同层级的健康体系中获得高质量的康复... 相似文献
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P. J. Magin PhD FRACGP S. Morgan MPH&TM FRACGP A. Tapley MMedStat C. McCowan PhD L. Parkinson PhD K. M. Henderson BNurs C. Muth MD MPH M. S. Hammer MSc D. Pond PhD FRACGP K. E. Mate PhD N. A. Spike MBBS FRACGP L. A. McArthur MBBS FRACGP FACRRM M. L. van Driel PhD FRACGP 《Journal of clinical pharmacy and therapeutics》2016,41(5):486-492