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排序方式: 共有1667条查询结果,搜索用时 15 毫秒
81.
This study was undertaken to find out whether sleep-related penile erections occur in the carbachol-induced rapid eye movement sleep model in rats. Bulbospongiosus EMG, as a measure of penile erection, was recorded along with EEG, EMG, and EOG during normal sleep-wakefulness. These parameters were again recorded after injection of carbachol into the pontine tegmentum. Carbachol-induced rapid eye movement sleep was not accompanied by penile erections. 相似文献
82.
Ettinger U Chitnis XA Kumari V Fannon DG Sumich AL O'Ceallaigh S Doku VC Sharma T 《The American journal of psychiatry》2001,158(1):116-118
OBJECTIVE: There is some evidence of thalamic abnormalities in schizophrenia. This study investigated thalamic volumes in patients experiencing their first episode of psychosis and nonpsychotic comparison subjects. METHOD: Magnetic resonance imaging scans were obtained for 38 patients and 29 comparison subjects. Patients' symptoms were rated by research psychiatrists using the Positive and Negative Syndrome Scale. RESULTS: Thalamic volumes were smaller in patients than in comparison subjects. There were no significant correlations between thalamic volumes and symptom scores. CONCLUSIONS: Thalamic abnormalities are present close to the onset of psychosis. 相似文献
83.
OBJECTIVE: Prepulse inhibition (PPI) of the startle response provides an operational index of sensorimotor gating that is reliably demonstrable in both human and animal subjects. Patients with schizophrenia, first-degree relatives of patients with schizophrenia, patients with schizotypal personality disorder and healthy individuals scoring high on psychometric measures of psychosis-proneness display reduced PPI. This study examined associations between individual differences in "psychosis-proneness" and brain activity during a tactile prepulse inhibition paradigm previously found to reveal activation in controls and deficient activation in schizophrenia patients in the striatum, thalamus, insula, hippocampal, temporal, inferior frontal, and inferior parietal regions. METHODS: Fourteen right-handed healthy men underwent psychophysiological testing and functional magnetic resonance imaging (fMRI) during a 15-min tactile PPI paradigm involving the use of tactile stimuli as both the pulse (a 40-ms presentation of 30psi air-puff) and the prepulse (a 20-ms presentation of 6psi air-puff presented 30-ms or 120-ms before the pulse). Individual differences in "psychosis-proneness" were assessed with Psychoticism scale of the Eysenck Personality Questionnaire-Revised (EPQ-R). RESULTS: High psychosis-proneness was associated with lower PPI and reduced activity in the inferior frontal gyrus, insula extending to putamen and thalamus, parahippocampal gyrus, and inferior parietal and middle temporal regions. No regional activity correlated positively with psychosis-proneness. CONCLUSIONS: The present observations extend the findings observed previously in people with schizophrenia to people with high psychosis-proneness, providing support to continuum theories of psychosis with implications for understanding trait-related neural deficits in schizophrenia. 相似文献
84.
Trimetazidine, a novel anti-ischemic agent, is used in the therapy of angina, vertigo and chorioretinal diseases. It has also been examined for its effect on nociception, inflammation and neuroprotection in various animal models. The present study was designed to investigate the effect of trimetazidine on electrically induced seizures in mice. Trimetazidine was administered orally in doses of 5, 10 and 20 mg/kg (single dose) to observe its effect on the increasing current electroshock seizure (ICES) test in mice. Trimetazidine in 10 and 20 mg/kg doses significantly raised the seizure-threshold current in the ICES test. Further, co-administration of per se ineffective dose of trimetazidine (5 mg/kg, p.o.) with sub-anticonvulsant dose of nimodipine (10 mg/kg, p.o.) and phenytoin (12.5 mg/kg, p.o.) offered significant protection in the ICES test. These results indicate that trimetazidine possesses significant anticonvulsant activity against electro-convulsions in the mice. 相似文献
85.
Orrell M Hancock GA Liyanage KC Woods B Challis D Hoe J 《International psychogeriatrics / IPA》2008,20(5):941-951
ABSTRACTBackground: People with dementia in care homes are at risk of having their views ignored and decisions are often made on their behalf by care home staff and family carers. The aim of this study was to compare the ratings of needs of older people with dementia living in care homes, as assessed by the older person themselves, a family caregiver, and the staff of the care home.Method: The Camberwell Assessment of Need for the Elderly (CANE) was completed for 238 residents with dementia by care staff. In addition, 149 users and 81 family caregivers also completed the assessment of the person's met and unmet needs.Results: Many users were able to report their met and unmet needs despite having moderately severe dementia. The views of the person with dementia were commonly in agreement with the staff and family carers' views. However, user and carer pairs had the lowest average percentage agreement of 63% compared to that of 77% between user and staff pairs. In particular, users reported relatively higher unmet needs for psychological distress, company and information, and high unmet needs for daytime activities and eyesight/hearing problems.Conclusions: Users' views on their needs should be sought even when the person has dementia and lives in a care home. Reliance solely on assessment by staff or carers may lead to under recognition of unmet needs. 相似文献
86.
Premkumar P Fannon D Kuipers E Cooke MA Simmons A Kumari V 《Behavioural brain research》2008,193(1):132-139
The frontal lobe has an extended maturation period and may be vulnerable to the long-term effects of schizophrenia. We tested this hypothesis by studying the relationship between duration of illness (DoI), grey matter (GM) and cerebro-spinal fluid (CSF) volume across the whole brain. Sixty-four patients with schizophrenia and 25 healthy controls underwent structural MRI scanning and neuropsychological assessment. We performed regression analyses in patients to examine the relationship between DoI and GM and CSF volumes across the whole brain, and correlations in controls between age and GM or CSF volume of the regions where GM or CSF volumes were associated with DoI in patients. Correlations were also performed between GM volume in the regions associated with DoI and neuropsychological performance. A longer DoI was associated with lower GM volume in the left dorsomedial prefrontal cortex (PFC), right middle frontal cortex, left fusiform gyrus (FG) and left cerebellum (lobule III). Additionally, age was inversely associated with GM volume in the left dorsomedial PFC in patients, and in the left FG and CSF excess near the left cerebellum in healthy controls. Greater GM volume in the left dorsomedial PFC was associated with better working memory, attention and psychomotor speed in patients. Our findings suggest that the right middle frontal cortex is particularly vulnerable to the long-term effect of schizophrenia illness whereas the dorsomedial PFC, FG and cerebellum are affected by both a long DoI and aging. The effect of illness chronicity on GM volume in the left dorsomedial PFC may be extended to brain structure-neuropsychological function relationships. 相似文献
87.
Heike Schmidt Jigar Jogia Kristina Fast Tessa Christodoulou Morgan Haldane Veena Kumari Sophia Frangou 《Human brain mapping》2009,30(11):3609-3615
Gender differences have been well established in verbal and spatial abilities but few studies have examined if these differences also extend into the domain of working memory in terms of behavioural differences and brain activation. The conclusions that can be drawn from these studies are not clear cut but suggest that even though gender differences might not be apparent from behavioural measures, the underlying neural substrate associated with working memory might be different in men and women. Previous research suggests activation in a network of frontal and parietal regions during working memory tasks. This study aimed to investigate gender differences in patterns of brain activation during a verbal version of the N‐back working memory task, which incorporates the effects of increased demands on working memory. A total of 50 healthy subjects, aged 18 to 58 years, that were equally split by gender were recruited matched for age, levels of education and ethnicity. All subjects underwent functional magnetic resonance imaging. We found that men and women performed equally well in terms of accuracy and response times, while using similar brain regions to the same degree. Our observations indicate that verbal working memory is not affected by gender at the behavioural or neural level, and support the findings of a recent meta‐analysis by Hyde ([ 2005 ]: Sex Roles 53:717–725) that gender differences are generally smaller than intra‐gender differences in many cognitive domains. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
88.
Neonatal outcome of 178 low birth weight (LBW) babies in this study was associated with 26.4% neonatal mortality. A significantly higher mortality rate was noted in presence of adverse maternal factors, birth weight less than 1.5 kg, prematurity and respiratory distress at birth. Premature rupture of membranes and leaking (greater than 12 h) were recorded in 75 cases. Significant association was observed for septicemia. Maternal postpartum weight less than 40 kg was associated with higher incidence of neonatal infections than when mother's weight was greater than 45 kg. 相似文献
89.
Liver dysfunction in severe birth asphyxia 总被引:1,自引:0,他引:1
A total of 46 full term, appropriate for gestational age neonates were included in this study. Out of this, 31 infants had suffered severe birth asphyxia, while 15 normal babies formed the control group. The liver function tests of the asphyxiated group was deranged in 64.52% babies. There was 60% mortality in asphyxiated babies with deranged liver function. The serum levels of transaminases (SGOT, SGPT) and alkaline phosphatase in non-survivors were significantly higher than those of survivors. 相似文献
90.