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51.
A case-control study with matched pairs was initiated to investigate the relationship between shoulder-neck complaints and activity in the upper trapezius muscle. The matching was done so that the physical demands from work (external exposure) were equal for both the case and the control. Each pair was also matched for gender, age, working hours, and employment time. Male (n = 18) and female workers (n = 78) employed in both manual and office work were included. Muscle activation levels and pause patterns during work and muscle activity during tests of attention, coordination, and rest were recorded by surface electromyography. The results showed consistent associations between pain and signs of increased activation of the upper trapezius for the cases in the manual group. No such associations were observed in the office group. The results are consistent with the hypothesis that muscle activation patterns may in some instances, but not in all, explain why some workers develop pain while others do not in work situations where the physical demands are similar.  相似文献   
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Examined the effects of two instructional methods on language generalization and longterm retention in 23 adults with autism and severe to profound mental retardation. Analog language teaching employed discrete trials in a controlled setting concentrating on discrimination and identification of materials. Natural language teaching emphasized instruction through interactions that occurred incidentally to training students in the use of materials to perform functional tasks. Assessments were conducted under conditions favoring analog teaching to assure against partiality toward natural language teaching. Under such disadvantageous conditions, the methods of natural language teaching would be supported by results showing either no difference or an advantage in their favor. Both techniques increased initial and long-term generalization though the results suggest no relative superiority for either method under these assessment conditions. A significant interaction was found between prior functioning level and sequence of instruction. Because natural language teaching has many strengths, few drawbacks, and produces equal generalization and retention under disadvantageous conditions, it is strongly supported as preferable for people with autism and mental retardation.The authors acknowledge the important assistance provided by the following people: the staff and management of the Behavior Development and Learning Center at CSH/DC directed by Israel Perel, Lisa Kramer, Steve Hafferkamp, James Lowdermilk, and, finally, and especially, to the participants themselves.  相似文献   
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Quisqualic acid NBM lesions had no effect on water maze performance, but slightly impaired passive avoidance acquisition. GammavinylGABA treatment alone had no effect on the passive avoidance and water maze performance, but aggravated acquisition deficit in rats subjected to NBM lesioning. However, gammavinylGABA-treated NBM-lesioned rats reached control level of performance.  相似文献   
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The effectiveness of THA (an anticholinesterae) on scopolamine (0.4 mg/kg) and nucleus basalis (NB) lesion-induced change in neocortical spectral electroencephalography (EEG) were investigated. Scopolamine increased the amplitudes of all the spectral components in waking-immobility. In the movement-related EEG spectral values, only the alpha power was increased. THA 7.5 mg/kg, but not THA 3 mg/kg, could reverse scopolamine-induced amplitude change. NB lesioning increased delta and theta amplitudes, but decreased beta amplitude. Delta amplitude was increased during movement recordings in NB-lesioned rats. THA 7.5 mg/kg and pilocarpine 10 mg/kg, but not THA 3 mg/kg, could partially reverse the increase of delta and theta amplitudes induced by NB lesions. However, the beta power decrease could not be restored with cholinomimetics. This study demonstrates that quantitative EEG activity analysis may reflect the THA-induced restoration of the function of the cholinergic nucleus basalis.  相似文献   
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Technetium-99m sestamibi was used for functional investigation of the muscle perfusion of lower extremities in 35 patients with peripheral vascular disease. The aim was to test what useful information could be obtained by additional imaging of the legs in patients referred for risk stratification with dipyridamole myocardial scanning. Posterior images were acquired over the thighs and calves after postocclusive reactive hyperaemia and at rest. Inter- and intraextremity ratios and differences between the stress and rest data were used for the assessment of abnormal circulation. Arteriography was performed in every case, and surgical procedures or transluminal angioplasty in 31 patients. To estimate diagnostic accuracy, the results of99mTc-sestamibi scintigraphy were compared with those of angiography and the functional consequences of revascularization procedures. The sensitivity and specificity of99mTc-sestamibi scintigraphy were 55% and 25%, respectively, with an overall accuracy of 50%. Apparently methodological error was not responsible for these poor results. Instead, a paradoxically high uptake of the radiopharmaceutical in muscles supplied by significantly stenosed vessels was identified as the main source of both false-negative and false-positive results. This phenomenon resembles the findings of a previous study involving delayed administration of thallium-201 after exercise. In conclusion,99mTc-sestamibi scintigraphy has not proved sufficiently reliable to help in the management strategy for patients with peripheral vascular disease.  相似文献   
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