DIASTOLIC OPENING OF THE AORTIC VALVE (AV) IN A CASE OF AORTIC INSUFFICIENCY DUE TO AV FENESTRATION

A patient with severe aortic insufficiency due to fenestration of the non-coronary aortic valve leaflet is described. A preoperative echocardiogram demonstrated early closure of the mitral valve and early diastolic separation of the aortic valve leaflets. These findings disappeared after partial surgical correction and subsequent hemodynamic improvement. Premature opening of the aortic valve is common in severe aortic insufficiency.     

家兔主动脉神经高阈压力感受反射快速重调中枢过程的机能特征

实验在37只乌拉坦麻醉家兔中进行,切断双侧主动脉神经(AN)、窦神经及迷走神经。以模拟高值保持压的条件刺激(0.5ms,10Hz,4—6V,5min)给予切断的 AN 中枢段,借以诱导高阈压力感受反射快速重调的中枢过程,旨在观察中枢重调过程对压力感受反射的影响。实验表明:(1)该中枢过程显著衰减由 AN A-纤维和 c-纤维混合传入所激发的压力感受反射降压效应(-45.5%,P<0.01,n=10)及肾交感神经活动抑制效应(-10.6%,P<0.05,n=11),(2)对选择兴奋 A-纤维激发的压力感受反射,仅衰减其降压效应(-32.1%,P<0.05,n=7),而不影响其肾交感神经活动抑制效应(2.4%,P>0.05,n=7),结果进一步证实:快速重调中枢过程对压力感受反射的衰减性影响和传入纤维成分的依赖关系,主要衰减诱导该中枢过程的同类纤维激发的压力感受反射。     

家兔主动脉神经低阈压力感受反射快速重调中枢过程的特征

40只家兔,乌拉坦静脉麻醉。切断双侧主动脉神经(AN)、窦神经及迷走神经。以选择兴奋 AN 有髓传人纤维的条件刺激(0.02ms,50Hz,4—6V,5min)给予切断的 AN 中枢段,模拟导致低阈压力感受反射快速重调的保持压背景,借以诱导快速重调的中枢过程。实验表明:该中枢过程使 AN 有髓纤维传入所激发的压力感受反射降压效应衰减41.82%(P<0.01),肾交感神经活动抑制效应衰减19.31%(P相似文献   

THE VALUE OF ELECTROMYOGRAPHY IN NEUROLOGY

By detection of muscular fibrillation, a sign of motor nerve impairment, through electromyography, diseases of the motor nervous system can be distinguished from muscular disorders, malingering, and psychoneurotic states. The site of lesion can be determined and the degree of impairment and progress of recovery can be estimated. The method has been used successfully in amyotrophic lateral sclerosis, poliomyelitis, peripheral neuritis and neuronitis, and root compression syndrome, as also for indirect evidence in muscular dystrophy and other myopathic conditions.