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L-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonists increase the threshold for electroshock-induced convulsions. Here, we show that a transgenic mouse line overexpressing cerebellum-restricted gamma-aminobutyric acid type A (GABA(A)) receptor alpha6 subunit in the hippocampal CA1 pyramidal cells (Thy1alpha6 mouse line) exhibits about a 20% increase in the electroshock current intensity inducing tonic hindlimb extension convulsion in 50% of the mice compared with that of their wild-type controls. AMPA receptor-mediated miniature excitatory postsynaptic currents (mEPSCs) in patch clamp recordings of CA1 pyramidal neurons in hippocampal slices had decreased amplitudes (8.4 +/- 2.2 pA) in the transgenics compared with the wild types (10.3 +/- 2.5 pA) but showed no change in current decay or frequency. Our results suggest that decreased AMPA-mediated neurotransmission might explain the increased threshold for electroconvulsions and warrant further studies on the regulation between various components of inhibition and excitation in neurons.  相似文献   
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This study investigated the relationship between alexithymia, depressive symptoms, and Youth Self-Report (YSR) self-image profiles among 13 to 18-year-old adolescents (n = 7087) attending school in Kuopio, Finland. The final sample consisted of 3936 adolescents (1801 boys, 2135 girls) who completed structured self-rating questionnaires (Toronto Alexithymia Scale [TAS] 20, Beck Depression Inventory [BDI], and YSR) during class periods at school. The overall prevalence of alexithymia was 7.3%. However, girls in all age groups were more frequently alexithymic than boys. Regardless of sex, alexithymic youths reported more depressive symptoms as well as internalizing and externalizing problems than the others. A YSR total score of more than 70 was recorded among 33.4% of alexithymic compared with 3.7% of nonalexithymic adolescents. The TAS-20 correlated significantly with the BDI score, YSR total score, and with internalizing problems. This study revealed alexithymia among adolescents to be associated with various complications such as depressive symptoms, high scores in YSR problem scales, and difficulties in social relationships. Our findings indicate that these adolescents are at high risk of mental disorders and require treatment interventions.  相似文献   
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The aim of this study was to assess the dopamine function of the temporal cortex in major depressive disorder using [123I]epidepride to image D2/3 receptor binding sites. Ten major depressives and 10 healthy controls were selected from a general population sample for single-photon emission computed tomography imaging. Among the major depressives there was a strong bilateral correlation between the scores on the 21-item Hamilton Depression Rating Scale and D2/3 receptor binding. Dopaminergic abnormalities may be present in the temporal cortices of major depressives.  相似文献   
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BACKGROUND: Geographical variation and sociodemographic characteristics may differ in affective and nonaffective psychotic disorders. We examined the geographical variation in the lifetime prevalence of psychotic disorders in a comprehensive general population study. METHOD: A nationally representative sample of 8028 Finns aged 30 or over was screened for psychotic and bipolar I disorders and interviewed with the Structured Clinical Interview for DSM-IV. Best-estimate DSM-IV diagnoses were formed by combining interview and case note data. Nationwide health care register data were used for the nonrespondents. Associations with sociodemographic features, place of birth and residence in urban or rural areas and in five regions, and migration between the regions were examined. RESULTS: Schizophrenia and other nonaffective psychoses, but not affective psychoses, showed prominent regional variation, with highest odds found for schizophrenia among those born in the North (OR 7.72 95%CI 2.48-24.04) and the East (OR 3.99 95%CI 1.22-13.11). The risk of any psychotic disorder was lower for those born in urban areas (OR 0.73 95%CI 0.54-0.98), but no associations were found for separate diagnostic groups. Region of birth was the strongest determinant of geographical variation when both place of birth and residence were accounted for. Selective migration was not found. Education and income were higher and being employed more common in subjects with affective psychosis than in subjects with other psychotic disorders. CONCLUSIONS: Large area variation is more important than urban-rural disparity in psychotic disorders in Finland. Affective psychoses were different from nonaffective psychoses in terms of both regional variation and sociodemographic features.  相似文献   
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Parallel input makes the brain run faster   总被引:1,自引:0,他引:1  
In serial sensory processing, information flows from the thalamus via primary sensory cortices to higher-order association areas. However, association cortices also receive, albeit weak, direct thalamocortical sensory inputs of unknown function. For example, while information proceeds from primary (SI) to secondary (SII) somatosensory cortex in a serial fashion, both areas are known to receive direct thalamocortical sensory input. The present study examines the potential roles of such parallel input arrangements. The subjects were presented with median nerve somatosensory stimuli with the instruction to respond with the contralateral hand. The locations and time courses of the activated brain areas were first identified with magnetoencephalography (MEG). In a subsequent session, these brain areas were modulated with single-pulse transcranial magnetic stimulation (TMS) at 15-210 ms after the somatosensory stimulus while electroencephalography (EEG) was recorded. TMS pulses at 15-40 ms post-stimulus significantly speeded up reaction times and somatosensory-evoked responses, with largest facilitatory effects when the TMS pulse was given to contralateral SII at about 20 ms. To explain the results, we propose that the early somatosensory-evoked physiological SII activation exerts an SII-->SI influence that facilitates the reciprocal SI-->SII pathway - with TMS to SII we apparently amplified this mechanism. The results suggest that the human brain may utilize parallel inputs to facilitate long-distance cortico-cortical connections, resulting in accelerated processing and speeded reaction times. This arrangement could also allow very early top-down modulation of the bottom-up stream of sensory information.  相似文献   
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A child with osteogenic sarcoma of the sacral spine has complex nursing and interdisciplinary team needs. The course of one patient is discussed, both from the patient and family's perspective and that of her inter-disciplinary care team. The need for a coordinated, holistic approach to care that involves advance planning, continual reassessment of goals, and clear communication among the team members and consulting services is clearly demonstrated.  相似文献   
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OBJECTIVE: The primary aim of this study was to compare the motor performance of physically well-recovered men with traumatic brain injury with that of healthy men. DESIGN: Cross-sectional study in a national rehabilitation centre. METHODS: Static and dynamic balance, agility and rhythm co-ordination of men with traumatic brain injury (n=34) and healthy controls (n=36) were assessed. Between-group differences in dynamic balance and agility were analysed by analysis of covariance and differences in static balance and rhythm co-ordination by logistic regression analysis. Cut-off points for clinical screening were determined by receiver operating characteristics analyses. RESULTS: Men with traumatic brain injury had impaired balance and agility compared with healthy men and in a rhythm co-ordination test they had difficulties in starting and sustaining simultaneous rhythmical movements of hands and feet. In receiver operating characteristics analyses a running figure-of-eight test (agility), tandem walking forwards (dynamic balance) and rhythm co-ordination test with fast tempo were found the most sensitive and specific for distinguishing between men with traumatic brain injury and the healthy men. CONCLUSIONS: The impairments in motor performance of physically well-recovered patients with traumatic brain injury were obvious. The results of this study extend the knowledge of problems in motor performance among patients with traumatic brain injury and provide further information for clinical rehabilitation.  相似文献   
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