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41.
Two methods of assessing candidates for coloured overlays were compared with the aim of determining which method had the most practical utility. A total of 58 adults were assessed as potential candidates for coloured overlays, using two methods; a questionnaire, which identified self-reported previous symptoms, and a measure of perceptual distortions immediately prior to testing. Participants were classified as normal, Meares-Irlen sensitive, and borderline sensitive. Reading speed was measured with and without coloured overlays, using the Wilkins Rate of Reading Test and the change in speed was calculated. Participants classified as normal did not show any significant benefit from reading with an overlay. In contrast, a significant reading advantage was found for the borderline and Meares-Irlen participants. Current symptom rating was found to be a significant predictor of the change in reading speed, however the previous symptom rating was not found to be a reliable predictor. These data indicate that the assessment of perceptual distortions immediately prior to measuring colour preference and reading speed is the most meaningful method of assessing pattern glare and determining the utility of coloured overlays.  相似文献   
42.
Self-inflicted burns represent a major social and medical problem for society. Differences have been demonstrated between patients who attempt suicide and those who deliberately harm themselves without any intention of killing themselves. These self-inflicted injuries may resemble injuries that are intentionally inflicted by others and may require investigation by protective services. Little is known about these specific pattern burn injuries in psychiatric patients.  相似文献   
43.
Reported are two cases of video-PSG captured head-rolling occurring, in the context of REM Sleep Behavior Disorder (RBD) episodes, in two patients affected with idiopathic RBD and without past personal or familiar history of Rhythmic Movement Disorder during sleep. It has been speculated that the activation of neuronal pathways which underlie REM-related loss of motor control in RBD, may involve the Central Pattern Generator neuronal networks leading to the induction of Rhythmic Movements during RBD episodes, thereby allowing the re-emergence, in pathological conditions in later life, of a motor behavior typically seen in the early stage of life.  相似文献   
44.
成年人智力发育与年龄和教育的关系   总被引:2,自引:0,他引:2  
本文对韦氏成人智力量表中国修订本25岁及其以上成年人城乡样本共1976人在校正各年龄组的文化程度以后,比较了年龄和教育因素对成年人智力发展的影响。结果发现:与晶体智力有关的测验成绩并不随年龄增大而下降,某些测验(如知识;领悟等)甚至呈上升趋势;与流体智力有关的测验成绩随年龄的增大而下降;而测量精神运动速度(数字符号测验)的成绩受年龄影响最为明显。看来流体-晶体智力理论能较好地解释成年人的典型智力发  相似文献   
45.
选用32只(64后肢)体重在11~18.5kg成年健康杂种狗,随机分为三组,每组10~11只。实验组将血管束植入源于肋骨、胫骨段的骨块内,并埋置肌间,对侧骨为无血管束植入的对照组。术后60~180天作大体观测、X线检查和组织学观察。在半数动物作骨缺血坏死模型实验的骨块,采用热灼法、蒸煮游离骨和硅膜包骨法,在不同时间内进行观察,其中以硅膜包骨的骨缺血坏死模型最为满意。实验证明,在血管束植入骨内后,可以重建血供,血管长入,骨细胞再生,发现有很多密集的成骨细胞、骨软骨母细胞、胶原纤维、新骨小梁和黄骨髓等组织,而无血管束植入的对照骨块均成为死骨。  相似文献   
46.
Effects of cueing on visuospatial processing in unilateral spatial neglect   总被引:2,自引:0,他引:2  
Patients with typical left unilateral spatial neglect bisected lines after cueing to the left end-point, the fixation point being monitored with an eye camera. They persisted with the point of initial fixation made after cueing and placed the mark there without searching leftwards again. The rightward shift of fixation to the initial point of fixation thus determined the location of the subjective midpoint. We consider that rightward attentional bias increased the amplitude of this shift that was planned on the basis of the perception of the whole line while cueing. This hypothesis may explain smaller but obvious rightward bisection errors found in the cueing condition.  相似文献   
47.
In a prospective study we compared duplex-ultrasound characteristics of symptomatic internal carotid artery (ICA) stenoses with cranial computerized tomographic (CCT) findings in 82 patients suffering from completed or transient middle cerebral artery symptoms. The aim was to assess the pathogenic role of ICA plaque morphology and the potential embolic risk of ICA plaques. The degree of carotid stenosis was estimated by spectral analysis of the pulsed Doppler signal. The CCT findings were classified as being either normal, lacunar lesions, hemodynamically induced low-perfusion infarctions, or territorial embolic infarctions. According to their ultrasonic features we characterized the ICA plaque surface as smooth or irregular and their structure as homogeneous or heterogeneous. Plaques with an irregular surface and heterogeneous echogenicity dominated significantly in CCT-territorial infarctions (p < 0.01), whereas hemodynamically induced low-perfusion infarctions showed no relationship with any plaque characteristic. High degree ICA stenoses (> 50>%) dominated in both territorial infarctions and low-perfusion infarctions, as compared to ipsilateral normal CCT or lacunes (p < 0.05). Normal CCT and lacunar infarctions were associated with homogeneous and smooth plaques (both p < 0.05). We conclude that > 50% ICA stenoses can cause both hemodynamically induced low-perfusion infarctions as well as thromboembolic territorial infarctions, whereas ulcerated and heterogeneous plaques constitute a high risk factor for arterio-arterial embolic stroke. Furthermore, carotid ultrasound may help to estimate the clinical significance of carotid lesions.  相似文献   
48.
Spinal cord/brainstem preparations from 5- to 8-day-old rats, maintained in vitro, were used to determine the cells of origin and regions of termination of fibers in the superficial ventrolateral funiculus (VLF) at a site from which rhythmic locomotor-like activity can be induced. Rhythmic locomotor-like activity was recorded from lumbar ventral roots after short trains of stimuli (50 Hz for 0.5-2 seconds) delivered to the VLF. Field potential mapping revealed that single VLF stimuli elicited responses in the ipsilateral ventrolateral medulla. Tract-tracing experiments by using biocytin, pressure-injected into the VLF, showed that only a small number of brainstem neurons were labeled and these were scattered bilaterally in the ventrolateral and lateral medulla. Dense concentrations of nerve terminals were found in the lateral reticular nucleus ipsilateral to the stimulation site. Labeled spinal cord neurons included a primary population of large cells distributed bilaterally in lamina VII from T13 to L4, with peak numbers in L2 ipsilaterally and in L3 contralaterally. Intracellular recordings revealed that some L2 and L3 neurons with rhythmic responses to VLF stimulation could be activated antidromically from the VLF, with latencies of less than 1.0 msec. These observations led us to speculate that the superficial VLF carries a locomotor-related tract originating bilaterally in lumbar lamina VII and terminating in the ipsilateral medulla, including the lateral reticular nucleus. This pathway may be part of the spinoreticular or spinoreticulotectal pathway that has been described in many species, the function of which has only loosely been ascribed.  相似文献   
49.
Pattern electroretinograms (PERGs) in response to 8.3 Hz alternating gratings (16.6 rev/sec) of different spatial frequencies were recorded in normal subjects as well as in patients affected by early glaucoma and ocular hypertension. In normal subjects the PERG response is spatially tuned, with a maximum at about 1.5 cycles/deg and attenuation at higher and lower spatial frequencies. In all cases of early glaucoma and in the great majority of cases of ocular hypertension the PERG was reduced, as compared with that of normal subjects, mainly in the medium range of spatial frequencies (at which the PERG has its maximal amplitude).  相似文献   
50.
We studied nine cases of retrobulbar neuritis with confirmed multiple sclerosis and six cases of optic atrophy from other causes. Pattern and focal electroretinograms (macular ERGs) were recorded with high (400 cd/m2) and low (40 cd/m2) intensity stimuli. Contrast sensitivity was also measured with a simple printed test.Luminance was not markedly important. High spatial frequency contrast sensitivity was significantly correlated with pattern ERG amplitude. Pattern and focal ERG amplitude ratio was usually reduced, but the effect was not correlated with contrast sensitivity or large enough to be useful clinically.In optic atrophy the pattern ERG (PERG) was clearly more severely reduced than the focal ERG (FERG). In retrobulbar neuritis both ERGs were equally and more severely reduced even though the visual losses were less. In unilateral cases the PERG increased then decreased after the initial attack, as previously described (Arden et al., 1982). The results suggest that retinal layers beyond the ganglion cells may be affected in retrobulbar neuritis, but proximally generated, pattern-specific ERG components are selectively lost in optic atrophy.  相似文献   
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