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In a single patient suffering from a major depressive episode with melancholia (DSM-III), both severe psychomotor symptoms, such as stupor and mutism, and mood disturbances could be abolished completely and promptly by administration of the benzodiazepine lorazepam. Remission of symptoms was entirely and immediately reversed by the benzodiazepine antagonist Ro 15-1788. These drug effects were constantly reproducible. Possible mechanisms of action and the influence of GABAergic neurotransmission on affective and psychomotor state are discussed.  相似文献   
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The etiological diagnosis of obstruction is difficult during pregnancy. The authors report 3 cases of this rare association: obstruction due to adhesions [1], volvulus of the transverse colon on a common mesentery [1] and obstruction due to an appendix abscess [1]. Complementary investigations, obviously limited under these circumstances, were based on plain abdominal X-rays, repeated if necessary. The diagnosis must be made early and appropriate treatment given in order to ensure a good materno-fetal prognosis as was obtained in these 3 cases.  相似文献   
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Impaired ability to conduct daily activities is a diagnostic criterion for dementia and a determinant of healthcare services utilization and caregiver burden. What predicts decline in instrumental activities of daily living (IADLs) is not well understood. This study examined measures of episodic memory, executive function, and MRI brain volumes in relation to baseline IADLs and as predictors of rate of IADL change. Participants were 124 elderly persons with cognitive function between normal and moderate dementia both with and without significant small vessel cerebrovascular disease. Random effects modeling showed that baseline memory and executive function (EXEC) were associated with baseline IADL scores, but only EXEC was independently associated with rate of change in IADLs. Whereas hippocampal and cortical gray matter volumes were significantly associated with baseline IADL scores, only hippocampal volume was associated with IADL change. In a model including cognitive and neuroimaging predictors, only EXEC independently predicted rate of decline in IADL scores. These findings indicate that greater executive dysfunction at initial assessment is associated with more rapid decline in IADLs. Perhaps executive function is particularly important with respect to maintaining IADLs. Alternatively, executive dysfunction may be a sentinel event indicating widespread cortical involvement and poor prognosis.  相似文献   
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The effect of iontophoretically applied cholecystokinin (CCK) on neurons of the neostriatum was studied in rats anaesthetized with urethane. The most frequently observed effect of the sulphated octapeptide (CCK-8S) on striatal neurons was excitation. Spontaneously active neurons responded more often to CCK-8S than quiescent cells. Silent, primarily non-responsive neurons could often be stimulated with CCK-8S using glutamate to induce an ongoing discharge. Thus, 45.8% of the 177 neurons studied changed their discharge rate by more than 30%. Certain CCK receptor antagonists could prevent the effect of CCK-8S, fully or at least partly, in the majority of CCK-responsive neurons. The data suggest that cholecystokinin modulates the firing of active neostriatal neurons via the CCKA or the CCKB receptor type. Furthermore, we compared neuronal responses to glutamate with those recorded during concomitant administration of CCK-8S in order to study the interaction of both transmitters, which may be colocalized in striatal afferents. CCK-8S mainly enhanced the excitatory effect of glutamate on striatal neurons, but in several neurons the response to glutamate was reduced. The CCKB receptor antagonist could prevent CCK-8S from increasing the glutamate-induced activation.  相似文献   
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The movement protein genes from several isolates of ArMV and GFLV of different geographical origins were amplified by RT/PCR using degenerate primers, cloned and sequenced. A single pair of degenerate primers was designed from these sequences to allow the simultaneous amplification of parts of the movement protein genes of ArMV and GFLV. Their use in an immunocapture-RT/PCR for the detection of ArMV or GFLV in infected grapevines proved to be ten times more sensitive than the corresponding ArMV or GFLV ELISA tests. A Sph1 restriction site found in the sequences corresponding to the amplified products from the GFLV isolates, but not in the amplified products from the ArMV isolates, allowed the differentiation between ArMV and GFLV in the infected grapevines by a Sph1 restriction digestion of the amplified products.  相似文献   
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