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11.
Mapping brain size and cortical gray matter changes in elderly depression.   总被引:1,自引:0,他引:1  
BACKGROUND: In elderly depression, volumetric brain imaging findings suggest abnormalities of the frontal lobe, particularly the orbitofrontal cortex, and the hippocampus. No studies to date have mapped cortical abnormalities over the entire brain surface in major depression. Here, we conducted detailed spatial analyses of brain size and gray matter within the cortical mantle in elderly patients with major depression. METHODS: High-resolution, three-dimensional, structural magnetic resonance imaging data and cortical pattern matching methods were used in 24 depressed elderly patients and 19 group-matched controls to measure local brain size and proportions of gray matter at thousands of homologous cortical surface locations. RESULTS: Prominent brain size reductions were observed in the depressed subjects in the orbitofrontal cortex bilaterally. Cortical gray matter measurements revealed significant gray matter increases in the orbitofrontal cortex, adjacent to focal trend level significant decreases of gray matter in the same region. Depressed patients also exhibited significant gray matter increases in parietal cortices, as well as the left temporal cortex. CONCLUSIONS: Complex cortical changes may contribute to the brain size reduction of the orbitofrontal cortex and to the gray matter abnormalities detected in orbitofrontal cortex and temporoparietal cortices, thereby providing a potentially new window into the pathophysiology of elderly depression.  相似文献   
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This paper analyses the diverse services currently available for children under five in the UK, and considers the nature of the demand for them. It recounts the initiative made by Strathclyde Region to co-ordinate and integrate pre-five provision, administratively and at a service level. It then considers the efforts of other local authorities to integrate administratively and looks at some of the complexities of attempting to do so at a service level.  相似文献   
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Patients suffering from semantic dementia provide important constraints on theories of the structure and organisation of semantic memory. In this article we report one such patient, AM, whose progressive deterioration of semantics enables us to address the much-debated issue of whether conceptual structure is hierarchically organised. The hierarchical account predicts that brain damage should impair lower levels of the hierarchy (property information) before affecting higher level (category) information (Warrington and Shallice, Q. J. Exp. Psychol. 1975, 27, 635–657). We evaluate this prediction by repeated testing of AM in two studies—a semantic priming task and a verification task—over an 18 month period, contrasting the progressive deterioration of properties (functional and perceptual) and category relations (category co-ordinates and category labels). Properties were preserved longer than category information, arguing against a hierarchical account of semantic memory. In addition, functional properties were most robust to brain damage, supporting our claim that functional information plays a special role in semantic representations (Durrant-Peatfield et al., Proc. 19th Ann. Conf. of the Cognitive Science Society. Erlbaum, Mahwah, NJ, 1997, pp. 193–198. Tyler et al., Cognitive Neuropsychol. 1997, 14, 511–545).  相似文献   
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We present these 3 cases to alert others to the possibility of severe pain with rapid shrinkage of fibroids occurring during LHRH analogue treatment. We suggest management of such events should not be surgical except for vaginal excision of prolapsed fibroid polyps.  相似文献   
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The present paper introduces the concept of the narcissistically vulnerable system by suggesting that organizations may manifest some of the same pathological characteristics as narcissistic individuals. The public mental hospital was chosen as an example of such a system. Reasons for its vulnerability were suggested and specific defenses, employed at the system level, were discussed. Finally, remedies for the repair of the narcissistically vulnerable system were considered.  相似文献   
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The release of newly synthesized 3H-dopamine (3H-DA) was measured in the rat striatum superfused, through a push-pull cannula, with a physiological medium enriched in 3H-tyrosine. The level of spontaneous 3H-DA release was dependent on the topographical localisation of the cannula in the striatum (anterior parts displayed higher levels than posterior ones) and on the anesthetic state (halothane anesthetized rats demonstrated higher levels than awake ones). Inhibition of DA inactivation processes by local application of benztropine (a DA reuptake inhibitor, 10−6 M) or by IV administration of pargyline (a MAO inhibitor, 100 mg/kg) enhanced the detectable outflow of 3H-DA from the striatum in both halothane anesthetized and awake rats. Local application of D-amphetamine (10−5 M) or acetylcholine (5 × 10−5 M) in the presence of eserine (5 × 10−5 M) evoked respectively a fivefold and a 30% increase in spontaneous 3H-DA release in halothane anesthetized rats. Inhibition of the firing of dopaminergic neurons by IV injection of gamma-hydroxybutyrate (400 mg/kg) produced a 30% decrease in striatal 3H-DA release. The present results demonstrate that the push-pull cannula method is suitable for the study of DA release in both the anesthetized and the awake rat.  相似文献   
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Journal of Prevention - The major issues involved in the design and implementation of effective school screening programs are addressed, using data from a longitudinal study following over 500...  相似文献   
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