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51.
The patterns of regional cerebral blood flow (rCBF) increases and decreases in PET were compared for unimodal vestibular, unimodal visual, and for simultaneous vestibular and visual stimulation. Thirteen healthy volunteers were exposed to a) caloric vestibular stimulation, b) small-field visual motion stimulation in roll, c) simultaneous caloric vestibular and visual pattern stimulation. Unimodal vestibular stimulation led to activations of vestibular cortex areas, in particular the parieto-insular vestibular cortex (PIVC), and concurrent deactivations of visual cortical areas [Brodmann area (BA) 17-19]. Unimodal visual motion stimulation led to activations of the striate visual cortex and the motion-sensitive area in the middle temporal/middle occipital gyri (BA 19/37) with concurrent deactivations in the PIVC. Simultaneous bimodal stimulation resulted in activations of the cortical representation of both sensory modalities. In the latter condition activations and deactivations were significantly smaller compared to unimodal stimulation. The findings are consistent with the concept of an inhibitory reciprocal vestibulo-visual interaction in all three stimulus conditions.  相似文献   
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Superior oblique myokymia is a rare movement disorder thought to be caused by vascular compression of the trochlear nerve. Direct display of such neurovascular compression by magnetic resonance imaging has been lacking. The goal of this study was to assess the presence of neurovascular contacts in patients with superior oblique myokymia, using a specific magnetic resonance imaging protocol. A total of 6 patients suffering from right superior oblique myokymia underwent detailed neuro-ophthalmological examination, which showed tonic or phasic eye movement. All patients underwent magnetic resonance imaging, using a magnetic resonance imaging Fourier transform constructive interference in steady-state sequence in combination with magnetic resonance imaging time of flight magnetic resonance arteriography both before and after the administration of Gd-DTPA. With this protocol, the trochlear nerve could be visualized on 11 of 12 sides (92%). Arterial contact was detected at the root exit zone of the symptomatic right trochlear nerve in all 6 patients (100%). No arterial contact was identified at the root exit zone of the asymptomatic left trochlear nerve in any of the 5 left nerves visualized. In conclusion, superior oblique myokymia can result from neurovascular contact at the root exit zone of trochlear nerve, and therefore should be considered among the neurovascular compression syndromes.  相似文献   
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We present a clinical classification of central vestibular syndromes according to the three major planes of action of the vestibulo-ocular reflex: yaw, roll, and pitch. The plane-specific syndromes are determined by ocular motor, postural, and perceptual signs. Yaw plane signs are horizontal nystagmus, past pointing, rotational and lateral body falls, deviation of perceived straight-ahead to the left or right. Roll plane signs are torsional nystagmus, skew deviation, ocular torsion, tilts of head, body, and perceived vertical in a clockwise or counterclockwise direction. Pitch plane signs are upbeat/downbeat nystagmus, forward/backward tilts and falls, deviations of the perceived horizon. The thus defined vestibular syndromes allow a precise topographic analysis of brainstem lesions according to their level and side. Special emphasis is placed on the vestibular roll plane syndromes of ocular tilt reaction, lateropulsion in Wallenberg's syndrome, thalamic and cortical astasia and their association with roll plane tilt of perceived vertical. Recovery is based on a functionally significant central compensation of a vestibular tone imbalance, the mechanism of which is largely unknown. Physical therapy may facilitate this central compensation, but this has not yet been proven in prospective studies.  相似文献   
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A postal survey of recently appointed consultant paediatricians was undertaken to determine whether they perceived their training had adequately equipped them for their current job. The response rate was 69% (207/299). After excluding replies from consultants trained outside the UK the analysis was carried out on 167 replies. Trainees held a mean 5.2 posts during general and higher professional training, necessitating a mean 1.8 house moves. Altogether 82% felt moves were beneficial to training but 46% found moves 'very disruptive' to family life. Only 12% of district general hospital and 22% of teaching hospital senior registrars took two research sessions a week. Supervision and training in research was absent or poor for more than 60%; 24% felt major changes and 55% moderate changes were needed to current training. Training in non-clinical skills was particularly in demand and a curriculum for both trainers and trainees with regular appraisals is required. Research at senior registrar level needs review and educational methods improved to achieve better training in a shorter period.  相似文献   
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Of forty children having undergone two or more years ago an irradiation of the brain case with cobalt-60 delivering doses between 1800 and 2400 R TD (n = 20) or a dose above 3500 R TD (n = 20), as a matter of fact ten presented pathological EEG findings which, however, may be interpreted as genetically determined characteristics, or instead in connection with a recurrence of the tumor just manifesting itself, or else as the consequence of a residual tumor or of the surgery performed. Pathological EEG findings on the account of radiation therapy apparently are much less frequent than morphological changes of the brain after radiation therapy. It is not necessary to assume that the latter need always have an effect upon the function of the infantine brain.  相似文献   
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BACKGROUND: In this study, the authors evaluated the clinical presentation of patients with T4b breast carcinoma, analyzed the impact of noninflammatory skin involvement on long-term survival, and addressed the question whether the T4 tumor category still has any justification. METHODS: The clinical course of a study group of 119 patients with skin involvement was compared with the outcome of a control group of 299 consecutive patients who had tumors of the same size but without skin involvement. All tumors were stratified into 1 of 4 subsets according to greatest tumor dimension, as follows: Group A, < or = 3.0 cm; Group B, 3.1-5.0 cm; Group C, 5.1-10.0 cm; and Group D, > 10.0 cm. RESULTS: The study group distribution of patients within the size subsets were as follows: Group A, 26.1%; Group B, 24.3%; Group C, 26.1%; and Group D, 23.5%. Differences in disease-specific survival between the tumor size subsets were significant (Groups A and B vs. Groups C and D; P < 0.0001). In contrast to large tumors (> 5.0 cm), carcinomas < or = 5.0 cm showed no statistical significant differences in disease-specific survival between study group patients and control group patients (Group A: P = 0.17; Group B: P = 0.31). CONCLUSIONS: There is a broad range of clinicopathologic breast carcinoma entities within the T4b category. For > 50% of patients with T4b breast carcinoma, the feature noninflammatory skin involvement had no significant prognostic impact. Approximately 25% of patients had an extent of disease similar to that observed in patients with Stage I-II disease and, thus, falsely were considered to have more advanced disease. Heterogeneity and a lack of prognostic significance suggest that a revision of the T4 category, a relic of historic tumor classifications, is necessary.  相似文献   
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