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91.
老年学习记忆减退大鼠齿状回突触的定量研究   总被引:2,自引:0,他引:2  
洪岸  姚志彬 《解剖学杂志》1996,19(3):222-224
据老年大鼠在Morris水迷宫中的行为表现,将其分为老年学习记忆减退和学习记忆正常两部分,采用透射电镜观察、拍片,对齿状回中分子层触的数量和大小进行体视学定量分析。  相似文献   
92.
本文采用双盲法对 IDA 和 NIDA学龄儿童各61名进行了认知能力测验及铁治疗前后的动态比较。结果表明:IDA 儿童识记再认、字母匹配反应时、数字扫描记忆和一般推理能力测验成绩较 NIDA 儿童差。经铁治疗的IDA 儿童,注意、短时记忆和心理动作反应速度均有明显提高。但对较高级认知能力的改善不明显。  相似文献   
93.
Cognitive deficits in patients with obstructive sleep apnea syndrome (OSAS) are well demonstrated, but the pathophysiology of these deficits is still controversial, as the relationship between OSA severity and cognitive deficits is usually weak. Our study considers the possible relationship between OSA-related cognitive deficits and the overall intellectual function of OSA patients. Forty-seven OSA patients and 36 normal individuals underwent a neuropsychological battery test assessing attention and alertness. According to the resulting IQ score, patients and controls were divided into a high-intelligence group (IQ > or = 90th percentile) and a normal-intelligence group (50 < or = IQ < 90%ile). Between the two patient groups there were no significant differences noticed, regarding OSA severity or sleepiness. High-intelligence patients showed the same attention/alertness performance compared with the high-intelligence controls. On the contrary, patients with normal-intelligence showed attention/alertness decline compared with the normal-intelligence control group. The two patient groups were re-examined with the same battery test after at least 1 year of CPAP treatment. At re-examination neither patient group showed any differences regarding attention and alertness compared with the control groups. We assume that high-intelligence may have a protective effect against OSA-related cognitive decline, perhaps due to increased cognitive reserve.  相似文献   
94.
ABSTRACT

Electrical Stimulation (ES) is a neurostimulation technique that is used to localize language functions in the brain of people with intractable epilepsy and/or brain tumors. We reviewed 25 ES articles published between 1984 and 2018 and interpreted them from a cognitive neuropsychological perspective. Our aim was to highlight ES as a tool to further our understanding of cognitive models of language. We focused on associations and dissociations between cognitive functions within the framework of two non-neuroanatomically specified models of language. Also, we discussed parallels between the ES and the stroke literatures and showed how ES data can help us to generate hypotheses regarding how language is processed. A good understanding of cognitive models of language is essential to motivate task selection and to tailor surgical procedures, for example, by avoiding testing the same cognitive functions and understanding which functions may be more or less relevant to be tested during surgery.  相似文献   
95.
Genetic Structure of Spatial and Verbal Working Memory   总被引:6,自引:0,他引:6  
Ando J  Ono Y  Wright MJ 《Behavior genetics》2001,31(6):615-624
Working memory (WM) encompasses both short-term memory (storage) and executive functions that play an essential role in all forms of cognition. In this study, the genetic structure of storage and executive functions engaged in both a spatial and verbal WM span task is investigated using a twin sample. The sample consists of 143 monozygotic (MZ) and 93 dizygotic (DZ) Japanese twin pairs, ages 16 to 29 years. In 155 (87 MZ, 62 DZ) of these pairs, cognitive ability scores from the Kyodai Japanese IQ test are also obtained. The phenotypic relationship between WM and cognitive ability is confirmed (r = 0.26–0.44). Individual differences in WM storage and executive functions are found to be significantly influenced by genes, with heritability estimates all moderately high (43%–49%), and estimates for cognitive ability comparable to previous studies (65%). A large part of the genetic variance in storage and executive functions in both spatial and verbal modalities is due to a common genetic factor that accounts for 11% to 43% of the variance. In the reduced sample, this common genetic factor accounts for 64% and 26% of the variance in spatial and verbal cognitive ability, respectively. Additional genetic variance in WM (7%–30%) is due to modality specific factors (spatial and verbal) and a storage specific factor that may be particularly important for the verbal modality. None of the variance in cognitive ability is accounted for by the modality and storage genetic factors, suggesting these may be specific to WM.  相似文献   
96.
目的 探讨盐酸多奈哌齐对轻、中型脑外伤患者认知障碍及临床预后的影响。方法 78例轻、中型脑外伤并认知障碍患者被随机分成治疗组和对照组,治疗组应用盐酸多奈哌齐10mg/d,对照组应用吡拉西坦8mg,一日3次服用,两组的治疗周期为12周。治疗前及治疗后12周,分别应用简明精神状态检测量表(MMSE)、国人修订成人韦氏智利量表(WAIS-RC)和格拉斯哥预后评分(GOS)评价疗效。结果 两组在治疗后12周,MMSE和WAIS-RC评分均较治疗前提高(P〈0.05)。治疗后12周,治疗组MMSE和WAIS-RC评分较对照组高(P〈0.05),治疗组GOS预后优良率明显优于对照组(P〈0.05)。结论 盐酸多奈哌齐对轻、中型脑外伤后认知障碍有积极治疗作用,并能改善临床预后。  相似文献   
97.
The ability of five purified amphibian antimicrobial peptides (dermaseptin-1, temporin A, magainin I, and II, PGLa), crude peptide fractions isolated from the skin of Rana pipiens and R. catesbeiana, and four antimicrobial peptides (AMPs) from hybrid striped bass (piscidin-1N, -1H, -2, and -3) were examined for their ability to reduce the infectivity of channel catfish virus (CCV) and frog virus 3 (FV3). All compounds, with the exception of magainin I, markedly reduced the infectivity of CCV. In contrast to CCV, FV3 was 2- to 4-fold less sensitive to these agents. Similar to an earlier study employing two other amphibian peptides, the agents used here acted rapidly and over a wide, physiologically relevant, temperature range to reduce virus infectivity. These results extend our previous findings and strongly suggest that various amphibian and piscine AMPs may play important roles in protecting fish and amphibians from pathogenic viruses.  相似文献   
98.
Family and Illness Predictors of Outcome in Pediatric Brain Tumors   总被引:1,自引:2,他引:1  
Investigated the prediction of cognitive and behavioral outcomesin 63 children with heterogenous brain tumors. Hierarchicalmultiple regression analyses were used to determine how family-relatedvariables added to the prediction of children's outcome overand above illness measures. The best predictors of children'sbehavior problems and adaptive behavior were family and demographicvariables, whereas the best predictors of achievement were illnessand demographic variables. A combination of family and illnessvariables, however, was the best predictor of intellectual functioning.In addition to identifying specific predictors of cognitiveand behavioral outcome in children with brain tumors, theseresults lend initial support for the inclusion of contextualfactors such as family stress, maternal coping, number of parentsin the home, and family SES measures in studies of how diseasefactors affect outcomes in pediatric brain tumor patients.  相似文献   
99.
Daytime tiredness or sleepiness and deficits in cognitive performance are common complaints in sleep disordered patients. Till now there are few studies comparing patients from different diagnostic groups of sleep disorders in the same experimental protocol. We studied the time course of cognitive functions and subjective alertness in a parallel group design with four groups of patients [narcolepsy, untreated or treated obstructive sleep apnea (OSA), or psychophysiological insomnia] and a control group of subjects without sleep complaints. Each group consisted of 10 subjects, matched for age and gender. After a night with polysomnography, subjects were studied for 10 h from 08:00 hours to 18:00 hours at 20 min intervals under standardized environmental conditions. Four psychological tests were applied, (1) a critical flicker fusion (CFF) test to measure optical fusion threshold (alertness); (2) a paper-and-pencil visual line tracking test (selective attention); (3) a visual analog scale (VAS) for tiredness/sleepiness; and (4) the Tiredness Symptoms Scale (TSS), a 14 items check list. Each test session lasted for 8 min, followed by a 12 min pause. The level and time course of cognitive performance and self-rating data were analysed with hierarchical linear mixed effects models. Cognitive tests showed decrements in alertness and selective attention in untreated patients with insomnia, narcolepsy, and sleep apnea. Narcoleptic patients and untreated OSA had a lower CFF threshold than controls, and for narcoleptic patients the time course differed from that of all other groups. In the visual tracking test the performance of all groups of patients was worse compared with normal controls. Self-rated tiredness/sleepiness was significantly more pronounced in the three groups of untreated patients than in control subjects.  相似文献   
100.
Subjective health complaints without or with minimal somatic findings (pain, fatigue) are common and frequent reasons for encounter with the general practitioner and for long-term sickness leave and disability. The complaints are often attributed to the stressors of modern life. Is this true? We interviewed 120 Aborigine Mangyans (native population, M age = 33.5 years, 72.5% women) living under primitive conditions in the jungle of Mindoro, an island in the Philippines, and 101 persons living in a small coastal town on the same island (coastal population, M age = 33.8 years, 60.4% women). Both groups had more musculoskeletal complaints, fatigue, mood changes, and gastrointestinal complaints than a representative sample from the Norwegian population (N = 1,243). Our common subjective health complaints, therefore, are not specific for industrialized societies.  相似文献   
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