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41.
BACKGROUND: Executive dysfunction has been reported at different ages in autism. It is not clear however, when this impairment emerges or how its expression is affected by development. METHODS: 61 non-mentally retarded autism participants (AUT) and 61 age, gender, and IQ matched typically developing participants (CON) were assessed with two oculomotor executive function tasks, the oculomotor delayed response task (ODR) and the antisaccade task (AS), as well as a visually-guided saccade sensorimotor task (VGS). RESULTS: The AUT group demonstrated impairments in response inhibition and spatial working memory at all ages tested. Developmental improvements in speed of sensorimotor processing and voluntary response inhibition were similar in both groups indicating sparing of some attentional control of behavior. Developmental progression in the speed of initiating a cognitive plan and maintaining information on line over time, however, was impaired in the AUT group indicating abnormal development of working memory. CONCLUSIONS: These results indicate that while executive dysfunction is present throughout development, there is evidence for both typical and atypical developmental progression of executive functions in autism. The plasticity suggested by the developmental improvements may have implications regarding appropriate developmental epochs and types of interventions aimed at enhancing cognitive capacities in individuals with autism.  相似文献   
42.
People undergoing medical procedures sometimes experience feelings that may influence the results. In this study, we explore the relationship between changes in mood state self-ratings and cerebral glucose metabolism during positron emission tomography (PET) in persons with age-associated memory impairment (mean age 59.4±9.8 years). Brain regions of interest involved in both mood and memory were examined. Mood ratings of increased boredom correlated significantly with mesial temporal and parietal asymmetry and decreased parietal metabolism. Mood ratings of increased fatigue correlated with basal ganglia asymmetry and the right basal ganglia and left mesial temporal metabolism. These findings suggest that subjective mood state changes during PET may influence metabolism in brain regions implicated in emotion and memory function in people with age-related memory complaints.  相似文献   
43.
The study evaluates the efficacy of a procedural memory stimulation programme in mild and mild-moderate Alzheimer's disease (AD). Twenty basic and instrumental activities of daily living have been selected, and divided into two groups, comparable for difficulty. Ten normal elderly subjects (age 68.0±4.8 years; MMSE score: 28.7±0.9; education: 7.6±3.5 years) were asked to perform the two groups of daily activities and the time required to perform the tasks of each group was recorded and used as a reference. Ten mild and mild-moderate AD patients (age 77.2±5.3 years; MMSE score: 19.8±3.5; education: 7.3±4.7 years) without major behavioural disturbances constituted the experimental group. Patients were evaluated in all 20 daily activities and the time employed was recorded at baseline and after a 3-week training (1 h/d, 5 d/week) period. Five patients were trained during the 3 weeks on half of the 20 daily activities and the other five patients were trained on the remainder. This procedure was adopted in order to detect separately the improvement in "trained" and "not trained" activities, allowing to control better the effects of the intervention. The assessment of the functional impact of the training was directly measured, through the variation of time employed to perform tasks before and after training. After 3 weeks of training a significant improvement was observed for the trained activities, from 3.6 to 1.9 standard deviations below the performance of the normal elderly controls ( P <0.05). AD patients improved also in not-trained activities from 3.5 to 2.7 standard deviations below the controls'performance ( P <0.05). The rehabilitation of activities of daily living through developing procedural memory strategies may be effective in mild and mild-moderate AD patients.  相似文献   
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目的观察奥明格健脑口服液对改善小鼠记忆作用的影响。方法断乳小鼠,体重12~14g,每组14~16只。把实验动物随机分为正常对照组、高剂量组、中剂量组和低剂量组,连续给样30d,进行跳台和水迷宫试验,以上试验按同样方法重复一次。结果两次小鼠实验表明,灌胃奥明格健脑口服液1mo后,跳台试验中受电击动物数和错误总数,各试验组均低于对照组,其中高剂量试验组显著低于对照组,而且潜伏期显著延长。水迷宫试验中,动物到达终点所需时间和错误总数,高中剂量组试验组均显著低于对照组。结论奥明格健脑口服液具有改善动物记忆的作用。  相似文献   
46.
Primary objective: This study seeks to extend previous findings by documenting memory performance in a sample of 70 children at 5 years post-injury. It was anticipated that increasing injury severity would be associated with decreased performance on working and complex memory tasks. It was also expected that injury severity would significantly predict memory, but that the time from insult to subsequent testing would be associated with an increased relationship to non-injury factors.

Research design: Participants were assessed at 5 years post-injury, aged between 6-14 years, using measures of immediate, working and complex memory.

Methods and procedures: The sample comprised 18 children who had sustained a severe TBI, 24 with a moderate TBI, 11 with a mild TBI and 17 healthy controls, matched for age, gender and socio-economic-status.

Results: Results indicated that severe TBI was associated with decreased complex auditory-verbal memory performance, although children with TBI did not display impairment on immediate, working or complex visual-spatial memory. While injury severity significantly predicted complex memory outcome, non-injury factors failed to significantly predict either working or complex memory performance.

Conclusions: Future research should be engineered towards further clarifying what influences recovery from childhood TBI in the elongated post-injury period.  相似文献   
47.
Antiviral cytotoxic memory CD8+ T cells adoptively transferred to mice which are persistently infected with lymphocytic choriomeningitis virus WE or DOCILE initially proliferated extensively; they either caused the death of the recipient or, alternatively, disappeared within a few days. Apparently, the complete and coordinated induction and stimulation by widely distributed viral antigen caused these memory T cells to die before virus had been eliminated from the host. Thus memory T cells are as susceptible to peripheral exhaustion/deletion as unprimed T cells. These results indicate possible limitations of exclusively CD8+ T cell-mediated adoptive immunotherapy against viral infections or tumors.  相似文献   
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背景 全科医生是基层医疗服务的“主力军”,现有关于全科医生胜任力的研究大部分强调应着力提升全科医生的知识和技能水平,忽略了全科医生内隐素质的重要性。目前我国仍缺乏评估全科医生内隐胜任力的有效工具,开发全科医生内隐胜任力量表(GPICRS)对于提高基层医疗服务质量具有重要意义。目的 编制GPICRS,并对其进行评价,旨在为提升全科医生胜任力提供一定的参考。方法 在文献分析和行为事件访谈的基础上,形成初始版量表。于2021年9—12月,采用随机抽样法,从全国选取380例全科医生为研究对象,采用初始版GPICRS对其进行调查,通过项目净化、探索性因子分析、验证性因子分析、信效度分析验证量表的合理性,基于加权平均法评价全科医生的内隐胜任力水平,比较不同特征全科医生的GPICRS平均总得分及各维度得分。结果 共回收有效问卷335份(88.2%)。GPICRS由工作动机、自我效能感、医学人文关怀和医学职业素养4个维度14个条目构成。探索性因子分析结果显示,KMO值为0.737,Bartlett’s球形检验χ2=592.715、P<0.001,表明数据适合进行因子分析;按特征根>1.00...  相似文献   
50.
The recognition of an unfamiliar juvenile rat by an adult rat has been shown to imply short-term memory processes. In this study the effect of various psychotropic drugs on this investigatory behaviour was examined. The procedure was as follows: an unfamiliar juvenile rat was placed in the home cage of an adult rat for 5 min. The time spent by the adult rat in investigating the juvenile was recorded. The adult rat was then immediately treated with vehicle or test compounds, and was again exposed for 5 min to the same juvenile 2 h later. At this time point vehicle-treated rats no longer recognized the juvenile rat, i.e. the time of investigation was similar to that observed during the first presentation. Arecoline (1 and 3 mg/kg IP), physostigmine (0.05 and 0.1 mg/kg SC), RS86 (0.5 mg/IP) and nicotine (0.125 and 0.5 mg/kg IP) reduced in a dose-dependent fashion the time spent in investigating the juvenile during the second exposure. This result cannot be attributed to nonspecific effects, since it was not observed when a different juvenile was used for the second exposure. The effect of arecoline was reversed by scopolamine, but not by methylscopolamine. Aniracetam reduced investigatory behaviour at the dose of 50 mg/kg IP. FG 7142 (5 mg/kg IP) and -CCM (0.4 mg/kg IP) were also active and their effect was reversed by Ro 15-1788. dl-Amphetamine (0.5 and 1 mg/kg IP), nomifensine (1.25–10 mg/kg IP) and strychnine (0.25 and 0.5 mg/kg IP) were ineffective or reduced this behaviour unspecifically. Social recognition may therefore represent a useful and simple test to detect compounds which enhance short-term, olfactory, memory and to assess in the same animals the specificity of this activity.  相似文献   
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