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51.
Intracellular recordings from neurons were carried out in cortical slices obtained from tissue removed from patients suffering from intractable seizures. The patients were divided into two groups based on the presence or absence of an anatomical abnormality that could be imaged preoperatively. The lesion or its surround was the presumptive epileptogenic area. The tissue removed from the patients without lesions was removed either for biopsy purposes or for access to epileptic tissue and was not considered epileptogenic. All neurons from patients without an imageable lesion, and some (19%) from patients with an imageable lesion, responded to orthodromic stimuli with a sequence of synaptic excitation followed by inhibition; these properties resembled those of normal rodent cortical slices. Different responses, classified as abnormal, were observed in 81% of the neurons in tissue specimens obtained near lesions. The most common was prolonged synaptic excitation with no noticeable inhibition, even at high stimulus strengths. In three resections, long latency all-or-none depolarization shifts were observed that resemble the classic paradoxical depolarization shift seen in in vivo extracellular recordings. Loss of specific inhibitory systems within the cortex may contribute in part to these abnormal responses. 相似文献
52.
53.
目的探讨耐药性癫癎颞叶和海马脑组织中磷酸化肌球蛋白轻链(phosphorylation of myosin light chain,P-MLC)及其激酶(myosin light chain kinase,MLCK)的表达在癫癎芽生形成中的作用。方法免疫组化检测32例耐药性颞叶癫癎中P-MLC及其激酶MLCK的蛋白质表达水平,并与对照组比较。结果P-MLC免疫组化结果显示,耐药性颞叶癫癎组颞叶光密度值(0.35±0.13)高于对照组(0.19±0.027,P<0.05);耐药组海马光密度值(0.41±0.02)高于对照组(0.10±0.06,P<0.05)。免疫组化结果显示耐药组的MLCK表达水平在颞叶组织和海马组织中较对照组无统计学差异(P>0.05)。结论P-MLC及其激酶MLCK的功能与苔藓纤维芽生关系密切,P-MLC蛋白质产物在耐药性癫中明显升高,但其磷酸化激酶MLCK的表达并不升高,提示MLCK和去磷酸化酶间动态平衡被打破是P-MLC升高的原因,而P-MLC的升高可能在苔藓纤维芽生的形成中发挥重要作用。 相似文献
54.
The effect of the experimental antiepileptic drug zonisamide (1,2-benzisoxazole-3-methanesulfonamide, ZNS) on the trigeminal complex of cats was compared with the effect of established antiepileptic drugs. Intravenous administration of 10-40 mg/kg ZNS significantly depresses descending excitatory mechanisms, as well as segmental and descending inhibitory mechanisms, but has only a minor effect on segmental excitatory mechanisms. This spectrum of activity is similar to that of valproate, and suggests that ZNS should also be a broad-spectrum antiepileptic drug. In agreement with our experimental observations, it has been found that ZNS is effective against complex partial, generalized tonic clonic, and myoclonic seizures. The antiepileptic profile of ZNS in conventional screening tests resembles that of carbamazepine (CBZ) and phenytoin. However, CBZ exacerbates rather than prevents myoclonic seizures. Our experimental model thus provides a more accurate prediction of ZNS's clinical spectrum of activity. The relationship of these findings to the mechanism of action of antiepileptic drugs is discussed. 相似文献
55.
Carbamazepine Side Effects in Children and Adults 总被引:9,自引:8,他引:1
John M. Pellock 《Epilepsia》1987,28(S3):S64-S70
Summary: Most of the side effects associated with carbamazepine (Tegretol® , USP, Geigy Pharmaceuticals) therapy are mild, transient, and reversible with an adjustment in dosage or rate of dosage increase. Direct reports to Geigy Pharmaceuticals for the period 1975 to 1986 totaled 371 hematologic, 396 dermatologic, and 156 hepatic and pancreatic occurrences out of more than 4 million patients treated. These include 27 cases of aplastic anemia and 10 of agranulocytosis. In a study of the incidence of side effects in 220 children below the age of 16 years who were receiving carbamazepine, drowsiness, loss of coordination, and vertigo were the most commonly observed side effects and were almost always transient and dose related. The findings of this study are comparable with those of other series assessing carbam-azepine-associated adverse reactions in children and adults. Overall, 30 to 50% of children and adults were reportedly free of side effects in these studies. Recommendations for carbamazepine therapy include education of patients and parents in the nature and likelihood of possible serious adverse reactions and routine monitoring to detect laboratory abnormalities. 相似文献
56.
The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl− did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity. 相似文献
57.
58.
Summary Clinical and experimental investigations have shown that magnesium depletion causes a marked irritability of the nervous system, eventually resulting in epileptic seizures. Although magnesium deficiency as a cause of epilepsy is uncommon, its recognition and correction may prove life-saving. Two case reports are presented which emphasize the importance of recognizing hypomagnesaemia in patients with acute intractable seizures. 相似文献
59.
Epilepsy After Stroke 总被引:48,自引:4,他引:44
A retrospective follow-up of 200 consecutive stroke patients [ischemic brain infarction (IBI) 157, intracerebral hemorrhage (ICH) 20, subarachnoid hemorrhage (SAH) 23] who were in need of ambulatory rehabilitation was conducted for a mean period of 40 months after stroke. Epilepsy developed in 33 (17%) patients. The occurrence of epilepsy was 14% in IBI, 15% in ICH, and 35% in SAH. Significantly more patients developed epilepsy in the SAH group than in the IBI group (8 of 23 vs. 22 of 157, p less than 0.05). Of the 33 patients, 15% had their first seizures within the first 2 weeks after stroke, and 55% developed epilepsy in 6 months. Forty-eight percent of the patients had generalized seizures. Antiepileptic drug (AED) treatment was started in 28 of 33 patients, of whom 17 still had seizures during follow-up. Epilepsy was an important consequence of stroke among patients who needed rehabilitation, especially in SAH patients. In most, this was due to arterial spasm leading to IBI. 相似文献
60.
Do weekly and fast-rotating shiftwork schedules differentially affect duration and quality of sleep?
F. M. Fischer Antonio Castro Bruni Adelaide Berwerth Claudia Roberta Castro Moreno Rosaneli Lima Fernandez Claudia Riviello 《International archives of occupational and environmental health》1997,69(5):354-360
Characteristics of shiftwork schedules can have distinct impacts on workers’ sleep. This report presents comparisons of the
effects of two different shiftwork schedules on duration and quality of the main sleep episodes in comparable worker populations
at two different petrochemical plants. No significant differences were found for sleep duration in comparing the two plants.
However, within each plant’s shift cycles, morning and night shifts showed shorter sleep durations than all other workdays
and days off. Quality of sleep was perceived as lowest for night shifts of both plant schedules, and of lesser quality for
weekly than for fast-rotating shifts. These results support recommendations for reducing the number of consecutive nights
of shiftwork. However, before recommending any optimal shift schedule, interactions of sleep duration and quality with shift
schedules need much further evaluation.
Received: 18 December 1995/Accepted: 18 July 1996 相似文献