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61.
Kuyk J  Spinhoven P  van Dyck R 《Epilepsia》1999,40(4):485-491
PURPOSE: Because the diagnosis of pseudoepileptic seizures (PESs) is mostly made by excluding epilepsy, availability of a positive criterion for PESs is of great importance. This study was aimed at the validation of a diagnostic technique that intends to provide in such a positive criterion. METHODS: In 17 patients with epileptic seizures (ESs) and 20 patients with PESs, a hypnotic procedure was performed by an investigator blind to other data to recover amnesia for the ictus. If recall was obtained, the experimental diagnosis PES was given; if not, ES was diagnosed. The experimental diagnoses were compared with the clinical, EEG-confirmed diagnoses. Hypnotizability was measured to determine the relation between the outcome of the test and hypnotizability of the patients. RESULTS: Recall for the ictus was obtained in 17 patients. Each of these had a clinical diagnosis of PES. Seventeen patients with "no recall" had a clinical diagnosis of ES, and three patients had PESs. This result yields a specificity of 100% and a sensitivity of 85% for the recall technique. Hypnotizability was significantly higher in patients with PESs than in patients with ESs. In some "low hypnotizables," recall was obtained, and in some "high hypnotizables," no recall was obtained. CONCLUSIONS: A positive recall test indicates PES. A sub-group of patients with PESs is characterized by a high level of hypnotizability. Hypnotizability is not crucial for outcome of the recall test. High hypnotic abilities are especially found in disorders in which it is supposed that "dissociation" is involved. It can be speculated that PES may be one of the dissociative phenomena.  相似文献   
62.
Kainic acid (KA) administered systemically to rats produces seizures and brain damage. We measured an increase in reactive oxidant species (ROS) during KA-induced seizures in the extracellular fluid (ECF) of the piriform cortex, a brain region known to be subsequently damaged. Intracerebral microdialysis samples were collected and assayed for isoluminol-dependent chemiluminescence before and after injection of KA (16 mg/kg, ip). Hydrogen peroxide (H2O2) concentrations were calculated from catalase-sensitive chemiluminescence, the difference between total and catalase-resistant chemiluminescence. During generalized tonic-clonic seizures, both total and catalase-resistant chemiluminescence increased significantly in samples from brain ECF. Catalase-resistant chemiluminescence, most likely produced by ascorbic acid, increased for a full hour during sustained seizure activity. H2O2 concentrations showed a trend towards elevation during seizures. Increased ROS suggest that oxidative stress occurs in brain ECF during sustained seizure activity.  相似文献   
63.
C G Lipinski 《Epilepsia》1977,18(1):13-20
In 17 patients with a long course of epilepsy astatic seizures became apparent after the age of 14 years. In the patients' childhood astatic seizures had not been observed. The patients suffered from epilepsies with absences and awakening grand mal or psychomotor fits and sleeping grand mal. The EEG revealed spike-wave variant and spike-and-wave complexes as in the Lennox-Gastaut syndrome. Age dependency of Lennox-Gastaut syndrome is discussed. The described type of epilepsy can be understood as a "Lennox-Gastaut syndrome of late onset".  相似文献   
64.
Seizures and civilian head injuries   总被引:4,自引:3,他引:1  
Although several studies have reported on the risk of "early seizures" (seizures occurring within 7 days following a head injury), the reported proportions of patients experiencing these seizures vary from 1.4 to 15%. This wide divergence may be due to problems with methodology such as case selection and definitions of head injury and early seizures. In a series of 702 patients admitted with a head injury to Cook County Hospital (CCH), Chicago, Illinois, 29 (4.1%) had early seizures. This proportion is twice as high as one previously reported in a comparable series. This may reflect an actual difference between the two series or a case selection bias serving to elevate the proportion of patients with early seizures at CCH.  相似文献   
65.
Partial Motor Epilepsy with "Negative Myoclonus"   总被引:4,自引:3,他引:1  
Three children had both nocturnal unilateral motor seizures and daytime ipsilateral "negative myoclonus" which occurred so frequently that it resembled asterixis. Neurophysiologic studies demonstrated lateralized spike discharges that were time-locked to postural lapse in the contralateral outstretched arm. The clinical course was characterized by good seizure control with benzodiazepines.  相似文献   
66.
Summary The authors report on six cases of cerebral tumours: three astrocytomas (two temporal and one frontal), two meningiomas (one parietal and one frontal), and a metastasis with a temporal location causing sensory-motor epileptic seizures ipsilateral to the lesion. The discussion includes comments on the pathogenesis of these manifestations viewed in the light of experimental and electrophysiological data, and on the hypotheses of the mirror focus, irritation of the supplementary motor and secondary somato-sensory areas, compression of the opposite hemisphere, and possible absence of decussation of the sensory-motor pathways. The false localization suggested by this type of paroxysmal seizures and their rare clinical occurrence is emphasized.  相似文献   
67.
68.
We examined the generation, propagation and pharmacology of 4-aminopyridine (4-AP)-induced epileptiform activity (EA) in the intact interconnected limbic structure of the newborn (P0-7) rat in vitro. Whole-cell recordings of CA3 pyramidal cells and multisite field potential recordings in CA3, CA1, dentate gyrus, and lateral and medial entorhinal cortex revealed 4-AP-induced EA as early as P0-1. At this age, EA was initiated in the CA3 region and propagated to CA1, but not to the entorhinal cortex. Starting from P3-4, EA propagated from CA3 to the entorhinal cortex. Along the CA3 septo-temporal axis, EA arose predominantly from the septal pole and spread towards the temporal site. Whereas the onset of 4-AP-induced EA decreased with age from 21.2 +/- 1.6 min at P0-1 to 4.7 +/- 0.63 min at P6-7, the seizure duration increased in the same age groups from 98 +/- 14 s to 269.4 +/- 85.9 s, respectively. The EA was blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) but not by DL-2-amino-5-phosphonovaleric acid (APV), (+)-MK-801 hydrogen maleate (MK-801) or (+/-)-alpha-methyl-4-carboxyphenylglycine (MCPG), suggesting that they were mediated by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)/kainate receptor activation. We conclude that: (i) the septal pole of the hippocampal CA3 region plays a central role in the generation of EA in the neonatal limbic system; and (ii) AMPA/kainate receptor-mediated EA can be generated in CA3 already at birth. Therefore, the recurrent collateral synapses and circuits required for the generation of EA are developed earlier than previously suggested on the basis of studies on hippocampal slices.  相似文献   
69.
The effects of L-cysteine on mitochondrial DNA (mtDNA) in mouse brain were investigated both in vivoandin vitro. An intracerebroventricular (icv) injection of L-cysteine (1.25 micromol/animal) caused mtDNA damage in brain frontal and central portions of the cortex, broad-spectrum limbic and severe sustained seizures in mice, and increased lipid peroxidation in the whole brain. The L-cysteine-mediated effects were prevented by an intraperitoneal (ip) preinjection of melatonin (20 mg/kg) or an intracerebroventricular preinjection of ganglioside GT1b (90 nmol/animal). Furthermore, in in vitroexperiments, L-cysteine (0.05, 0.5, or 1.0 mM) caused damage to brain mtDNA and increased lipid peroxidation in a concentration-dependent manner when incubated at 37 degrees C for 20 or 60 min with a homogenate prepared from whole mouse brains. However, the mtDNA damage and the increased lipid peroxidation were completely abolished by a cotreatment with melatonin (1.5 mM), a potent scavenger of the hydroxyl radical (*OH), or ganglioside GT1b (60 microM), a potent inhibitor of glutamate-receptor-mediated activation and translocation of protein kinase C and lipid peroxidation. These results suggest that reactive oxygen species including the *OH may be involved in l-cysteine-induced brain mtDNA damage, lipid peroxidation, and development of seizures in mice. Therefore, we concluded that *OH scavengers, such as the pineal hormone melatonin and ganglioside GT1b, can protect against brain mtDNA damage, seizures, and lipid peroxidation induced by reactive oxygen species producers such as L-cysteine.  相似文献   
70.
Infantileintractablediarrhea(IID)wasusuallycomplicatedwithmalnutrition,growthretardationandpulmonaryinfection,etc.Itisdifficulttocure,andmortalityisratherhigh.TheauthorsusedintegratedtraditionalChi neseandwesternmedicinetherapytotreatit,andsatisfacto…  相似文献   
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