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121.
A preview tracking task has been developed which has particular application to neurological assessment and rehabilitation. Generated and monitored by a graphic display computer, it permits accurate global quantification of the upper-limb sensory-motor system. The incorporation of 'preview' into the tracking task is considered to significantly increase its effectiveness and relevance in relation to normal daily activities. Applied to three groups of normal subjects, several features of normal psychomotor performance and learning were identified or verified: hand dominance is not significant in overall arm control; learning does not completely plateau; increase in age (15-59 years) results in only a minor overall decrement in performance; an initial wide performance distribution decreases dramatically in subsequent sessions. Applied to brain-damaged patients, particularly head injury or stroke, the preview tracking task allows assessment at regular intervals enabling sensory-motor recovery curves to be generated. The potential of this technique, to help determine the efficacy of therapeutic procedures on the recovery process, is illustrated with the presentation of results from three brain-damaged patients demonstrating zero, significant and disjointed recovery of sensory-motor function. The usefulness of the preview tracking task can be expanded by combination with a less frequently applied but more component specific neurological assessment battery. 相似文献
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The first case of the unstable Hb Genova as a result of sporadic mutation is described. It is found in a 3-year-old Canadian boy of East Indian extraction with chronic Heinz body haemolytic anaemia. 相似文献
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Fluorescence depolarization is used to examine the effects of contaminants on the microviscosity of cell membranes of Ankistrodesmus sp. cells. One mg/L additions of Hg and Cd to the alga caused a change in the measured “index of viscosity” of the Ankistrodesmus cells in comparison to the index obtained by the addition of Zn and Pb. Elutriates from contaminated Niagara River sediment samples also caused an increase in the “index of viscosity,” whereas elutriate from uncontaminated sediments from the mid-lake station of Lake Ontario had no effect. This method has the potential for application in the assessment of the effects of contaminants on algal populations. 相似文献
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JM Larner H Lee RD Little PA Dijkwel CL Schildkraut JL Hamlin 《Canadian Metallurgical Quarterly》1999,27(3):803-809
An asynchronous culture of mammalian cells responds acutely to ionizing radiation by inhibiting the overall rate of DNA replication by approximately 50% for a period of several hours, presumably to allow time to repair DNA damage. At low and moderate doses, this S phase damage-sensing (SDS) pathway appears to function primarily at the level of individual origins of replication, with only a modest inhibition of chain elongation per se. We have shown previously that the majority of the inhibition observed in an asynchronous culture can be accounted for by late G1cells that were within 2-3 h of entering the S period at the time of irradiation and which then fail to do so. A much smaller effect was observed on the overall rate of replication in cells that had already entered the S phase. This raised the question whether origins of replication that are activated within S phase per se are inhibited in response to ionizing radiation. Here we have used a two-dimensional gel replicon mapping strategy to show that cells with an intact SDS pathway completely down-regulate initiation in both early- and late-firing rDNA origins in human cells. We also show that initiation in mid- or late-firing rDNA origins is not inhibited in cells from patients with ataxia telangiectasia, confirming the suggestion that these individuals lack the SDS pathway. 相似文献
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OBJECTIVE AND IMPORTANCE: We present a case report of a patient with a left frontal brain abscess. Cultures obtained from the abscess at the time of surgery were identified as dental flora known to establish a synergistic relationship in polymicrobial infections. This type of synergistic relationship makes the clearance of an infection more difficult for an intact immune system. A serum immunoglobulin (Ig) Type A deficiency was identified postoperatively. This immunodeficiency may have contributed to the development of the abscess. CLINICAL PRESENTATION: The patient presented with headaches and photophobia. Computed tomography of the head performed with intravenously administered contrast demonstrated a left frontal brain abscess. INTERVENTION: The patient was operated on through a left frontal approach, carefully avoiding the frontal sinus. The abscess was aspirated, and the patient was treated with intravenous antibiotics for several weeks. Postoperatively, the patient did well. There were no signs of enhancement on follow-up computed tomographic scans at 7 and 12 months postoperatively. CONCLUSION: Through a comprehensive immunological workup, an IgA deficiency was identified postoperatively. Although the deficiency of a single type of Ig may be asymptomatic, complications from recurrent or chronic bacterial infections may occur. The deficiency of IgA, combined with a synergistic polymicrobial infection, contributed to the development of an intracranial abscess. A patient presenting with a brain abscess without any predisposing medical history should be evaluated for an underlying immune deficiency. 相似文献
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