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To determine if impaired dichotic performance in patients with dementia of the Alzheimer type is due to the inability to divide attention or the inability to perceive degraded auditory stimuli, we measured performance on tasks of both dichotic and degraded monotic speech materials. We also examined whether perception of degraded speech stimuli presented monaurally is related to abnormalities of temporal lobe anatomy and physiology, as we have shown for dichotic performance. Although the patients were impaired on both dichotic and monotic tests, significantly greater impairment was seen on the dichotic test. Our earlier finding of a significant relation between dichotic performance and measures of anterior temporal lobe atrophy and reduced glucose metabolism was replicated, but no significant relation was found between monotic tests and measures to temporal lobe integrity. We conclude that the inability to divide attention, rather than abnormal processing of degraded stimuli per se, is reflected in poor dichotic performance in patients with dementia of the Alzheimer type, and that dichotic performance, unlike degraded monotic perception, depends directly on the integrity of temporal cortex in these patients.  相似文献   
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Mid- to long-term outcome of disc excision in adolescent disc herniation.   总被引:3,自引:0,他引:3  
BACKGROUND CONTEXT: Adolescent disc herniation and its surgical treatment have been the subjects of many published clinical series. The majority of these series were heterogeneous; the number of adolescent patients (12-17 years) as opposed to young adults (18-20 years) was generally small and the length of follow-up varied greatly. Although the short-term outcome of disc excision in adolescents was mostly favorable, their long-term outcome is unknown. OBJECTIVES: To evaluate the mid- and long-term results of discectomy in patients younger than 17 years of age. STUDY DESIGN: Retrospective examination of a series of adolescent patients under the age of 17 years who underwent surgery for lumbar intervertebral disc herniation. PATIENT SAMPLE: The medical records of 26 patients (15 males, 11 females, 12-17 years old [average 14.6]) who were operated for lumbar intervertebral disc herniation in three spine centers between 1984 and 2002 were reviewed. These subjects represented the total number of patients meeting the criteria of adolescents undergoing discectomy for lumbar disc herniation in these institutions during the study period. All patients were located and contacted by an independent observer not involved in the care of these patients. Low back pain associated with leg pain was the main clinical symptom in 20 patients (77%), leg pain in 4 (15%), and back pain in 2 (8%). They all underwent posterior disc excision: 23 (88%) patients had one level discectomy, and 3 (12%) had simultaneous discectomy at two levels. The L4-L5 interspace was involved 19 times, and the L5-S1 interspace 10 times. Slipped vertebral apophysis was diagnosed in 4 patients (15%). Twelve of the 26 patients (46%) had a first-degree relative with a history of lumbar disc herniation. OUTCOME MEASURES: Telephone interviews provided follow-up data for 26 patients. Results were classified as excellent, good, moderate, or poor according to current symptom status, the need for additional surgery, the Oswestry Disability Index, and back and leg pain scores. RESULTS: The average time from surgery to follow-up was 8.9 years (range 3-21 years). At follow-up, the clinical results were excellent in 13 patients (50%), good in 4 (15%), moderate in 8 (31%), and poor in 1 (4%). Four subjects (15%) underwent a subsequent disc excision in the lumbar region, and one of them later underwent fusion. CONCLUSIONS: Discectomy provides satisfactory clinical results in young patients with disc herniation. The rate of reintervention (15%) is comparable to that in adults, indicating that discectomy for young patients should be approached similarly to that in adults.  相似文献   
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The country/region of origin of all original papers appearing in the International Journal of Psychiatry (IJGP) during the first 9 years of its publication was recorded. A more detailed analysis of citation patterns was carried out on the 105 original articles published during 1992. The results indicated that 50–60% of the articles emanated from the United Kingdom but that in general authors cited a broad range of specialities from journals published around the world. North American authors tended to cite North American sources more frequently than did their counterparts from other countries. There was evidence that the impact of the IJGP is increasing despite its omission from some scientific reference databases.  相似文献   
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Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.  相似文献   
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Bombings and explosion incidents directed against innocent civilians are the primary instrument of global terror. In the present review we highlight the major observations and lessons learned from these events. Five mechanisms of blast injury are outlined and the different type of injury that they cause is described. Indeed, the consequences of terror bombings differ from those of non-terrorism trauma in severity and complexity of injury, and constitute a new class of casualties that differ from those of conventional trauma. The clinical implications of terror bombing, in treatment dilemmas in the multidimensional injury, ancillary evaluation and handling of terror bombing mass casualty event are highlighted. All this leads to the conclusion that thorough medical preparedness to cope with this new epidemic is required, and that understanding of detonation and blast dynamics and how they correlate with the injury patterns is pivotal for revision of current mass casualty protocols.  相似文献   
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Thirty-three patients with primary gastrointestinal lymphoma (GIL) followed at Ankara University Medical School have been evaluated. The most frequent locations of the disease are the small intestine (48.4%) and the stomach (39.3%). The intermediate and high grade lymphomas constitute 84.8% of the cases. The mean age of the patients with small intestinal lymphoma is 28.7 years and 47.1 years for those with gastric lymphoma. The patients treated with surgery and chemotherapy (S+CT) have a longer survival than those treated with chemotherapy (CT) alone. In conclusion: 1) Small intestinal lymphoma occurs more frequently than gastric lymphoma in our study. 2) The median age of the Turkish patients with primary GIL is approximately 10 years less than those in the Western countries. 3) The therapeutic results of S+CT are superior to those of CT in the early stages of the disease.  相似文献   
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