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21.
Deborah G Murdoch Eaton David Wertheim Rowena Oozeer Lilly MS Dubowitz Victor Dubowitz 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(5):486-492
Murdoch Eaton DG, Wertheim D, Oozeer R, Dubowitz LMS, Dubowitz V. Reversible changes in cerebral activity associated with acidosis in preterm neonates. Acta Paediatr 1994;83:486–92. Stockholm. ISSN 0803–5253
Computerized online EEG monitoring in ventilated preterm infants less than 32 weeks' gestation enabled evaluation of the effect of acidosis on cerebral function. All episodes of acidosis were found to be associated with changes in the levels of cerebral activity. In 21 of the 32 episodes, EEG activity returned to pre-acidosis levels after therapeutic intervention. The duration of EEG abnormality was related to the severity of acidosis. However, the time to recovery of the EEG after therapeutic procedures was not related to duration of the EEG change. 相似文献
Computerized online EEG monitoring in ventilated preterm infants less than 32 weeks' gestation enabled evaluation of the effect of acidosis on cerebral function. All episodes of acidosis were found to be associated with changes in the levels of cerebral activity. In 21 of the 32 episodes, EEG activity returned to pre-acidosis levels after therapeutic intervention. The duration of EEG abnormality was related to the severity of acidosis. However, the time to recovery of the EEG after therapeutic procedures was not related to duration of the EEG change. 相似文献
22.
Lars Ohlson 《Neurourology and urodynamics》1988,7(4):365-376
This study was undertaken to determine the nature of pressure changes in manometric studies of renal pelvis and calyces. In previous studies in pigs it has been assumed that pressure increases occur in the contracting segments of the renal pelvis and calyces, but our observations suggested that these increases were actually due to distension of noncontracted segments. Pressures were recorded with two catheters introduced percutaneously into the pyelocalyceal system with simultaneous video recording of the fluoroscopic image. There was no pressure rise in the calyces or the renal pelvis when these segments contracted; however, pressure rose when the noncontracted calyces were distended by a remote contraction ring. These findings confirmed the observations at kinetic urography. They agreed with the hydrodynamic experience that the pressure in a ring-shaped contracted segment is lower than upstream and downstream of that segment. It was concluded that if the porcine pyelocalyceal system is a valid model of the human, the pressure increases, assumed to be contractions, were actually caused by the injection and distension of the noncontracted segments. 相似文献
23.
目的:观察影像学和脑电图对儿童缺氧缺血性脑病的应用对照及意义。方法:对65例缺氧缺血性患儿作影像学和脑电图检查。结果:脑电图正常6例(9.23%),轻度异常13例(22.03%),中度异常37例(61.03%),重度异常9例(16.94%),脑电图异常率为90.77%。脑电图异常表现为弥漫性慢波增多和局限性癎性放电。影像学异常44例,异常率为67.69%。结论:影像学和脑电图检查对儿童缺氧缺血性脑病的诊断及治疗有一定的帮助。 相似文献
24.
小儿非癫痫性发作临床分析 总被引:2,自引:0,他引:2
目的 对小儿时期的各种非癫痫性发作进行分析。方法 对 3 2例疑似非癫痫性发作的患儿进行临床分析 ,同时进行录像脑电图或 2 4h动态脑电图监测。结果 3 2例患儿发作期及发作间期脑电图均无异常放电 ,证实为非癫痫性发作 ,以生理性发作最多 (16例 ,占 5 0 % ) ,其平均年龄最小 (3 .5岁 )。结论 儿童时期存在多种形式的非癫痫性发作 ,以生理性发作最多 ,且非癫痫性发作易被误诊为癫痫及其他疾病 ,采用动态脑电图监测对诊断及鉴别诊断均有指导意义 相似文献
25.
Emerging research has shown that sleepiness, defined as the tendency to fall asleep, is not only determined by sleep pressure and time of day, but also by physiological and cognitive arousal. In this study we evaluated (i) the impact of experimentally induced cognitive arousal on electroencephalogram (EEG) defined sleep latency, and subjective, somatic and cortical arousal, and (ii) whether experimentally induced cognitive arousal enhances performance on a driving simulator test. Twelve healthy sleepers each spent three nights and the following day in the sleep laboratory: an adaptation, a cognitive arousal and a neutral testing day. In the cognitive arousal condition, a visit of a television camera crew took place and subjects were asked to be interviewed. On each testing day, a 5-min heart rate recording, subjective sleepiness and arousal scales, Multiple Sleep Latency Test and a 25-min driving simulator task were scheduled three times at 2-h intervals. Experimentally induced cognitive arousal resulted in significant increases in objective sleep latency. Significantly elevated levels of subjective and somatic arousal--as indexed by a subjective arousal scale and heart rate--were also evidenced following cognitive arousal induction. A marginally significant trend for increased cortical arousal, measured by EEG beta activity, was also found. No effects were found on driving simulator performance. These findings support the concept of cognitive arousal as a significant component in determining sleep latency. In addition, it was illustrated that cognitively induced arousal can provoke increases in somatic and possibly even cortical arousal in normal sleepers. However, this was not accompanied by an enhanced ability to perform adequately on a driving simulator test. 相似文献
26.
目的:探讨脑电图对脑震荡预后的诊断价值.方法:对86例临床确诊脑震荡的患者常规进行脑电图检查.结果:边缘脑电图3例,轻度异常脑电图42例,中度异常脑电图2例,异常率为54.7%.结论:脑电图应作为脑震荡必备检查方法.有助于客观评估病情,及时指导治疗和法学鉴定. 相似文献
27.
N. S. Popova O. B. Butenko O. S. Adrianov R. Veskov 《Bulletin of experimental biology and medicine》1992,114(1):984-987
Brain Research Institute, Russian Academy of Medical Sciences, Moscow. Institute of Biological Research, Belgrade, Yugloslavia. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 7, pp. 56–58, July, 1992. 相似文献
28.
目的 :观察五音乐曲刺激对精神分裂症患者脑电活动产生的影响。方法 :选取 2 0例精神分裂症患者和 10名正常对照 ,分别记录安静时段及聆听五音乐曲时段的脑电图 ,将脑电信号转化为功率数值 ,将 β/α定义为脑电活动率。 结果 :1、正常人与精神分裂症患者的脑电活动率在安静状态差异无显著性 (P >0 0 5 )。在听乐曲时患者的脑电活动率在C3、T3、T4、T5导联中 ,明显高于正常人 (P <0 0 5 )。 2、正常人在安静状态和听乐曲时其左右脑脑电活动率差异无显著性 (P >0 0 5 )。精神分裂症患者在安静状态左右脑脑电活动率在O1、O2及T5、T6导联间差异有显著意义 (P <0 0 5 ) ,并且听乐曲时在P3、P4和C3、C4以及F7、F8导联间差异有显著意义 (P <0 0 5 )。结论 :在五音乐曲的刺激下 ,精神分裂症患者的脑电反应与正常人不同。 相似文献
29.
目的探讨视频脑电图(VEEG)对小儿癫痫的诊断价值。方法对102例临床拟诊为癫痫患儿进行4~8h视频脑电图监测,其中包括清醒、睡眠期记录;分析临床发作和异常放电的关系,异常放电出现的时相。结果监测到临床发作并且同步异常放电者23例,仅发作间期癫痫样放电者53例,两者共76例(76/102,74.51%)结合病史确定为癫痫,其中局灶性52例(52/76,68.42%),睡眠中出现55例(55/76,72.37%)。10例(10/102,9.80%)临床发作但无同步异常放电,判定为非癫性发作。结论视频脑电图可提高儿童癫痫诊断的正确率,有助于癫痫的定位,部分剥夺睡眠有助于癫痫样放电的检出率。 相似文献
30.
R P Vertes 《Neuroscience》1984,11(3):669-690
The origins of projections within the medial forebrain bundle from the upper brainstem were examined with the horseradish peroxidase technique. Labeled cells were found in approximately 15 upper brainstem nuclei following injections of a conjugate of horseradish peroxidase and wheat germ agglutinin at various levels of the medial forebrain bundle. Labeled nuclei included (from caudal to rostral): dorsal and ventral parabrachial nuclei; Kolliker-Fuse nucleus; dorsolateral tegmental nucleus; A7 (lateral pontine tegmentum medial to lateral lemniscus); median and dorsal raphe nuclei; distinct group of cells oriented mediolaterally in the dorsal pontine tegmentum below the central gray; B9 (ventral midbrain tegmentum dorsal to medial lemniscus); retrorubral nucleus; nucleus of Darkschewitsch, interfascicular nucleus; rostral and caudal linear nuclei; ventral tegmental area; medial part of substantia nigra, pars compacta; and the supramammillary nucleus. With the exception of the ventral parabrachial nucleus, Kolliker-Fuse, A7, B9 and substantia nigra, pars compacta, each of the nuclei mentioned above sent strong projections along the medial forebrain bundle to the rostral forebrain. Sparse labeling was observed throughout the pontine and midbrain reticular formation. With the exception of the dorsal raphe nucleus, projections to the most anterior regions of the medial forebrain bundle (level of the anterior commissure) essentially only arose from presumed dopamine-containing nuclei-retrorubral nucleus (A8 area), interfascicular nucleus, rostral and caudal linear nuclei, substantia nigra pars compacta, and ventral tegmental area. Evidence was reviewed indicating that major forebrain sites of termination for these dopaminergic nuclei are structures that have been collectively referred to as the 'ventral striatum'. It is concluded from the present findings that several pontine and mesencephalic cell groups are in a position to exert a strong, direct effect on structures in the anterior forebrain and that the medial forebrain bundle is the main communication route between the upper brainstem and the forebrain. 相似文献