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1.
Short History of Interventional Neuroradiology What about the Future?   总被引:1,自引:0,他引:1  
1 Short historical background of interventional neuroradiology Even if a number of us were among the pioneers of Interventional Neuroradiology, this specialty has now reached its period of maturity. Schematically, the era of the pioneers began forty years ago and lasted about 15 years, between 1960 and 1975. During that period, on the initiative of Fedor Serbinenko (Russia) and Ren6 Djindjian (France), "intracerebral navigation " using small balloons, which became gradually "detachable", has been invented. At the same time, we discovered how to use these balloons to occlude intracranial vascular lesions, inaccessible or hardly accessible to traditional open skull neurosurgery, for example, carotid cavernous fistulas. Very rapidly, a lot of different embolic particles were successively tested, ranging at first from pieces of muscle, to small glass or silastic beads, gelfoam and dura mater pieces... During this period, parallel progress of hyperselective catheterization and consequently of microangiography allowed to establish new classifications of main vascular pathologies (distinction between brain arteriovenous malformations and dural fistulas ... ). These new classifications allowed a better understanding of physiopathology. This first period was thus primarily devoted to development of very precise diagnosis and techniques of hyperselective endovascular occlusion.  相似文献   
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Neural activity was recorded from the median nerve of a monkey during grasping and lifting, using a chronically implanted cuff electrode. At the onset of lifting, there was an initial dynamic response during which the intensity of the neural signal increased rapidly. This neural response attained its peak value well before the displacement, the load force or the grip force. The time course and peak of the rectified, integrated neurogram were best correlated with the rate of change of grip force. The neural activity declined exponentially to a steady value following the initial peak. During steady holding the mean amplitude of the neurogram was best correlated with the mean grip force. At the end of the holding phase there was a short burst of neural activity as the monkey relaxed the grip force and released the object. During some blocks of trials pulse perturbations were applied to the object. When the monkey did not increase the grip force in advance of the perturbation, the perturbation produced a relatively large displacement of the object and a burst of neural activity whose onset coincided with the onset of displacement. When the monkey anticipated the perturbation by increasing the grip force during the holding period preceding the perturbation, the perturbation produced a relatively small displacement and relatively little increase in neural activity.  相似文献   
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In recent trials in The Gambia, mass chemoprophylaxis with Maloprim administered over several years by primary health care workers to children aged 3-59 months has reduced both mortality and morbidity without inducing impairment of natural immunity or significant development of drug resistance. Taking expenditure of both time and money, by both public authorities and village volunteers, into account, the costs and the cost effectiveness of such mass chemoprophylaxis are estimated here. The cost per child protected per season was (1990 US) $2.84; the cost per childhood death averted was $143. Both costs compare favourably with those of permethrin bed net impregnation. So in some circumstances where malaria is holoendemic, control of childhood malaria by chemoprophylaxis may be more economically efficient than provision of impregnated bed nets.  相似文献   
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Book reviews     
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Summary. A pseudo-tumour due to metallosis is described in association with an iso-elastic hip replacement. This is a relatively rare lesion which may be difficult to diagnose. Scintigraphy and radiography may be helpful in distinguishing the lesion from a primary or secondary neoplasm, but the presence of osteolysis adjacent to the prosthesis will suggest the true nature of the lesion.
Résumé. Les auteurs rapportent un cas de manifestation pseudo-tumorale d’une métallose sur prothèse de hanche de type iso-élastique. Il s’agit d’une lésion relativement rare qui peut parfois avoir un aspect inquiétant. Elle nécessite un bilan radiologique et scintigraphique pour éliminer une tumeur primitive ou secondaire, mais le diagnostic est facilement évoqué devant une ostéolyse au contact de la prothèse. Nous décrirons notre démarche diagnostique et thérapeutique dans ce cas.


Accepted: 29 February 1996  相似文献   
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Selective attention to facial emotion and identity in schizophrenia.   总被引:4,自引:0,他引:4  
The selective attention to facial emotion and identity was investigated in 12 patients with schizophrenia and 12 healthy participants. Both patients and controls were required to perform two classification tasks (according either to identity or emotion). Two separate values for identity (person A/person B) and for emotion (fear/anger) were used. When the classification task was on one dimension, the other dimension was either correlated, constant, or orthogonal (Garner WR. The Processing of Information and Structure. Potomac, MD: Erlbaum, 1974, Garner WR. Interaction of stimulus dimensions in concept and choice processes. Cognitive Psychology 1976;8:98-123). Results indicated that both patients and healthy participants had an asymmetrical pattern of performance: they were able to selectively attend to the identity of the face presented, regardless of the emotion expressed on the face, but variation in identity interfered with the classification of facial emotion. Moreover, a correlational study indicated that the identity interference on emotion classification for schizophrenic patients covaried with the severity of their negative symptoms. The selective attention competencies in schizophrenia and the independence hypothesis of emotion and face recognition are discussed in the framework of current face recognition models.  相似文献   
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