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61.
The voltage-sensitive dye diO-C2-5 was used to produce an in vivo map of the membrane potential in two types of seizures. Mild limbic seizures were induced in rats with kainic acid; clonic convulsive seizures were induced with bicuculline. Kainic acid animals showed various levels of neural depolarization during their seizures in limbic, thalamic, cortical, and brainstem sites. The bicuculline animals showed uniformly greater levels of neural depolarization during their seizures. The magnitude of these changes relative to controls varied across seizure models and reflected the different underlying neural mechanisms for each model. The ability of the technique to capture local electrical events provides a new tool in which to explore brain activity. 相似文献
62.
高血糖对急性颅脑伤预后的影响 总被引:25,自引:1,他引:24
对ICU收治的61例急性闭合性颅脑伤患者入院24h血糖水平与急性期格拉斯哥昏迷评分、颅脑伤不同类型及预后进行分析。结果提示:格拉斯哥昏迷评分与血糖水平经回归分析呈显著负相关(r=-0.964,P<0.01);不同类型颅脑伤患者以脑挫裂伤组血糖最高。高血糖组患者病死率明显高于非高血糖组,死亡组患者血糖明显高于恢复不良组及恢复良好组。作者认为,血糖测定有助于了解颅脑伤的严重程度,同时可以估计患者的预后,在颅脑伤的救治过程中加强血糖监测是必要的。 相似文献
63.
Summary Changes occurring in serotonin neurons during hyperthermia-induced convulsions were examined by means of a modified immunohistochemical method. All mice (8–12 weeks of age) exposed to the temperature of 50°C had convulsions, showing a generalized tonic and/or clonic pattern. Immediately after the convulsions, the animals were perfused transcardially with a fixative. A significant reduction in serotonin immunoreactivity was observed in the neostratum (caudate-putamen complex) of the mice which had hyperthermia-induced seizures, while the serotonin immunoreactivity remained unchanged in the neocortex and paleostriatum. These results suggest that serotonin may be an important mediator in the mechanism of hyperthermia-induced convulsions or that the susceptibility of serotonin neurons to a convulsive state is greatest in the neostriatum.Supported in part by Grant No. 86-05 from the National Center for Nervous, Mental and Muscular Disorders (NCNMMD) of the Ministry of Health and Welfare and Grant No. 62770677 from the Ministry of Education, Science and Culture, Japan 相似文献
64.
Abstract Aggressive behaviour is rarely observed as an ictal semiology. Ictal aggression can occur in lesions of frontal and limbic
structures. In limbic structure lesions, the main mechanism of aggressive behaviour is hyperactivity; whereas frontal lesions
may cause aggressive behaviour with an indirect mechanism in which the suppression on limbic system is lost. Here we present
a patient with ictal aggression. In this case a right frontoparietal epileptiform focus was detected during the postictal
period. Magnetic resonance imaging showed cortical dysplasia on the right inferior frontal gyrus. The seizures disappeared
completely after pharmacological treatment. 相似文献
65.
目的:探讨颅脑外伤严重程度及CT征象与预后的关系,并探讨CT复查的最佳时间及临床意义。方法:回顾性分析80例颅脑外伤的严重程度与初次CT征象的关系,统计分析复查CT发现新病变的数目、程度及时间。结果:颅脑外伤的严重程度与初次CT征象符合率为92.5%(74/80)。外伤后即刻昏迷、CT显示重度复合伤、脑干损伤或弥漫性脑白质损伤的病死率达70.0%(21/30)。1~3d复查CT发现迟发性病变80个,4—7d21个,7d后8个。结论:临床病情与CT征象变化对判断预后有重要意义,颅脑外伤后3、7d是复查CT的最佳时机,出现病情变化应随时复查。 相似文献
66.
Hal Blumenfeld 《Epilepsia》2007,48(S4):18-26
Summary: Functional magnetic resonance imaging (fMRI) has become a widely used imaging modality in the past decade in both human studies and animal models. Epilepsy presents unique challenges for neuroimaging due to subject movement during seizures, and the need to correlate the timing of often unpredictable seizure events with fMRI data acquisition. These challenges can readily be overcome in animal models of epilepsy. Animal models also provide an opportunity to investigate the fundamental relationships between fMRI signals and brain electrical activity through invasive studies not possible in humans. fMRI studies in animal models of epilepsy can enable us to correctly interpret fMRI signal increases and decreases in human studies, ultimately elucidating specific networks that will be targeted for improved treatment of epilepsy. 相似文献
67.
肥厚型心肌病预后评估的研究进展 总被引:1,自引:0,他引:1
肥厚型心肌病是最常见的遗传性心脏病,其临床表现及预后极富多样性。该病患者的不良转归主要有:猝死、心力衰竭以及心房颤动所致的栓塞事件等。现就影响肥厚型心肌病预后的因素作一综述。 相似文献
68.
69.
《中华医学杂志(英文版)》2005,118(22):1912-1917
Nacosoupnhtraierysn,geesaple cciaarllcyin oinm aEu (r oNpPeC a)nd is N roartrhe Ainm emriocsat(incidence rate below 1/100 000 people per year)·However, it has a high incidence in several southernareas in China, especially in the Cantonese region,including Guangzhou city, where the incidence rate isapproximately 30 -80/100 000 people per year·1Inthe high incidence areas, more than 95% NPCs arepoorly differentiated (WHO types 2 and 3), which aresensitive to radiotherapy and chemotherapy… 相似文献
70.
Vegard Bruun Wyller 《Acta neurologica Scandinavica》2007,115(S187):7-14
Background – In this article, current scientific knowledge on the chronic fatigue syndrome (CFS) is reviewed. The US case definition of CFS (the CDC-definition) is most widespread in research and clinical practice. Estimates of prevalence vary from 0.2% to above 2%. The female–male ratio is approximately 3:1.
Clinical Features – Severe fatigue is the dominating complaint; it is worsened from exertions and not substantially relieved by rest. In addition, the patients might have a varying combination of accompanying symptoms. Clinical evaluation should be based upon standardized guidelines, including an assessment of functional impairments.
Pathophysiology – The pathophysiology should be interpreted within a biopsychosocial framework. Present knowledge suggests that certain genetic polymorphisms and personality traits might be regarded as predisposing factors, some infections and severe psychosocial stress constitute precipitating factors, whereas disturbances of immunity, skeletal muscle, cognitive abilities, endocrine control and cardiovascular homeostasis are possible perpetuating factors.
Treatment – Cognitive behavioural therapy and graded exercise therapy are of proven value in randomized controlled trials. Several pharmaceutical measures have been explored and found to have no beneficial effect. Most patients might expect long-term improvement, but full recovery is rare; however, the prognosis is better among adolescents. 相似文献
Clinical Features – Severe fatigue is the dominating complaint; it is worsened from exertions and not substantially relieved by rest. In addition, the patients might have a varying combination of accompanying symptoms. Clinical evaluation should be based upon standardized guidelines, including an assessment of functional impairments.
Pathophysiology – The pathophysiology should be interpreted within a biopsychosocial framework. Present knowledge suggests that certain genetic polymorphisms and personality traits might be regarded as predisposing factors, some infections and severe psychosocial stress constitute precipitating factors, whereas disturbances of immunity, skeletal muscle, cognitive abilities, endocrine control and cardiovascular homeostasis are possible perpetuating factors.
Treatment – Cognitive behavioural therapy and graded exercise therapy are of proven value in randomized controlled trials. Several pharmaceutical measures have been explored and found to have no beneficial effect. Most patients might expect long-term improvement, but full recovery is rare; however, the prognosis is better among adolescents. 相似文献