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41.
Partially purified (Na+,K+)-ATPase (E.C. 3.6.1.3.) was investigated in the epileptic cortex of audiogenic DBA/2 mice and in the primary and secondary foci of cats with acute or chronic freeze lesions. No differences in specific activities measured at 3 mM K+ were observed between epileptic and control cortex, except an increase of enzymic activities in the primary focus of acutely lesioned cats. The (Na+,K+)-ATPase catalytic subunits were resolved by SDS-gel electrophoresis and their phosphorylation levels were measured in presence of K+ ions and phenytoin. K+ was more effective in inducing maximal dephosphorylation of (Na+,K+)-ATPase in C57/BL, with identical affinity in the two strains. Phenytoin decreased the net phosphorylation level of (Na+,K+)-ATPase by about 50% in C57/BL mice, but only by 20% in DBA/2 mice. Both K+ and phenytoin dephosphorylating influences were decreased in primary and secondary foci of acutely lesioned cats. Those changes were limited to the alpha(-) subunit. In chronic cats, the dephosphorylating step of the (Na+,K+)-ATPase catalytic subunit recovered a normal affinity to K+, but its sensitivity to phenytoin remained decreased. Those differences in K+ and phenytoin influences on brain (Na+,K+)-ATPases between control and epileptic cortex might be responsible for the ictal transformation and seizure spread. In cats, the alteration of the alpha(-) isoform could mainly affect the glial cells.  相似文献   
42.
视频脑电图诊断儿童癫痫128例   总被引:4,自引:1,他引:3  
赵新  王宝西  王峰 《医学争鸣》2002,23(7):664-666
目的 分析视频脑电图(Video-EEG)在小儿癫痫诊断,分类中的应用价值及癫痫发作期的EEG特点。临床诊断的癫痫患儿128(男94,女34)例,1mo-14岁,平均年龄5.4岁,应用伟思VEEG1161B型视频脑电图仪,对患儿进行至少4-6h包括清醒与睡眠期的临床和EEG监测。监测中对各种状态及事件进行标记,结束后将EEG信号与临床录象资料同步回放并逐秒分析。结果 128例癫痫患儿中有54例(42.2%)进一步确定了癫痫综合征的诊断,其中儿童良性癫痫伴中央-颞区棘波25例,儿童失神癫痫3例,少年肌阵挛癫痫1例,额叶癫痫5例,West综合征13例,Lennox-Gastaut综合征7例,有49例(38.3%)可明确其发作类型,其中强直或(和)阵挛发作10例,部分性发作33例,肌阵挛发作5例,失张力发作1例,另外有25例(19.5)尚无法分类。结论 视频脑电图 是诊断癫痫及明确癫分类的可靠检查方法。  相似文献   
43.
用微量马桑内酯注入Wistar大鼠左侧前肢运动皮质,造成急性局灶型癫痫。用光镜、电镜和体视学方法研究其运动皮质第V层结构的改变。结果显示:癫痫大鼠运动皮质灶区、灶旁区的神经细胞数和胶质细胞数均分别比对照大鼠灶区和灶旁区显著减少;灶区神经毡中突触性终末数,显著减少;突触性终末的面积分数明显减少,而树突的面积分数无变化;神经胶质突起的面积分数增加。  相似文献   
44.
本文报道100例原发全身性癫痫家系的遗传流行病学研究结果。先证者一级亲属患病率为6.86%,二级亲属为1.03%;分别是对照组一级亲属的13.83倍和2.08倍。原发全身性癫痫的遗传度为:一级亲属0.7521±0.0678,二级亲属0.3592±0.0746;加权平均0.5743±0.0502。说明遗传因素起重要作用。发病年龄影响因素分析表明:原发全身性癫痫有一定年龄依从性。EEG家系分析显示,该型癫痫一级亲属癫痫样放电明显高于对照组一级亲属,提示癫痫样放电的遗传倾向。  相似文献   
45.
46.
颅内神经节细胞胶质瘤(附8例报告)   总被引:4,自引:1,他引:3  
目的探讨颅内神经节细胞胶质瘤的临床特征及治疗效果。方法回顾性分析8例颅内神经节细胞胶质瘤的临床资料。结果平均发病年龄27岁,肿瘤位于大脑半球6例,脑干2例。临床表现主要为癫,影像学检查无特异性表现。显微手术全切5例,大部切除3例,放、化疗4例。随访3个月~5年,7例症状明显缓解,1例复发。结论神经节细胞胶质瘤呈相对良性过程,癫为其主要临床表现,治疗上应手术全切;对有术后残留或间变者可给予放、化疗,预后相对良好。  相似文献   
47.
目的探讨颞叶癫痫颅内EEG记录与颞叶海马病变程度的关系。方法视频EEG证实为颞叶癫痫并经MRI检查的病人序贯进入本研究,采用硬膜下电极及深部电极联合纪录,确定领先发作释放(initialictaldischarge,IID)部位。37例病人中,无或轻度海马萎缩(hippocampalatrophy,HA阴性组)27例,中至中度HA(HA阳性组)者10例。海马病理变化依据MRI检查的海马容积测量及术后组织病理学的海马硬化分级。结果本组HA阴性组27例病人中,9例病人IID广泛出现在海马区、内侧旧皮层及外侧新皮层;3例在海马区及内侧古皮层;14例完全出现在海马区以外的颞叶皮层;仅1例局限于海马区。在HA阳性组中,90%的病人IID局限于海马区(P<0.05),在25例低级别海马硬化(HS)中,IID局限于海马区显著低于12例HS高级别病人(P<0.05)。结论颞叶癫痫的抽搐发作放电定位与海马的病理变化存在着密切关系,无HA和低级别HS病人的IID多出现在海马、颞叶内侧皮层、颞叶新皮层的部位,而HA明显者和高级别的HS病人出现的IID往往仅局限于海马(HF)。  相似文献   
48.
It is not well established whether seizures and epilepsy after an ischaemic stroke increase the disability of patients. Seventy-two patients with delayed seizures after a hemispheric infarct (37 with a single seizure and 35 with epilepsy) were included in the study. The modified Rankin scale was used to compare disability of the patients at 1 month after stroke and at 2 weeks after single or the last seizure, in case of epilepsy. The size of the X-ray hypoattenuation zone was compared on computed tomographic (CT) scans, performed in the weeks after the stroke and 1 week after single or repeated seizures. Lesion size was determined by superimposing the CT slices on digital cerebral vascular maps, on which the contours of the infarct area were delineated. The extent of the infarcts was expressed as the percentage fraction of the total surface area of the cerebral hemisphere. Groups with a single seizure and with epilepsy were mutually compared. Infarcts predominated in the parieto-temporal cortical regions. In the overall group the median Rankin score worsened significantly after seizures. The average size of the X-ray hypoattenuation zone was also significantly increased on the CT scans after the seizures, compared with those after stroke, without clear evidence of recent infarction. Mutual comparison of patients with a single seizure episode and of those with epilepsy showed only a trend of more severe disability and of increase in lesion size in the post-stroke epilepsy group. Delayed seizures and epilepsy after ischaemic stroke are accompanied by an increase in lesion size on CT and by worsening of the disability of the patients. This study does not allow to determine whether this is due to stroke recurrence or due to additional damage as a result of the seizures themselves.  相似文献   
49.
目的:从脑内铁代谢的角度研究铁在外伤后癫(PTE)发病机制中的可能作用。方法:用ELISA方法检测PTE大鼠模型脑组织内铁蛋白(Ft)和转铁蛋白(Tf)的动态含量。结果:早期Ft在整个脑组织内呈现为即刻反应性升高,15d后其含量在实验对侧脑组织内恢复至正常范围,而在实验侧脑组织内呈现继续升高的趋势;Tf含量只在实验侧脑组织内升高,且呈现随时间继续升高趋势。结论:PTE大鼠模型中的铁代谢过程十分复杂,相关蛋白尤其是Tf含量的增加提示铁可能是外伤后癫灶形成机制的一部分。  相似文献   
50.
Summary:  Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits.  相似文献   
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