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61.
目的利用扩散张量成像(DTI)直方图分析,明确血管性认知损害(VCI)患者的脑异常改变及DTI直方图指标与简易智能量表(MMSE)评分的相关性。方法对19例VCI患者和19例健康志愿者行常规MRI和DTI检查,获得全脑平均扩散率(MD)和各向异性分数(FA)图像后,分别绘制出全脑FA和MD直方图并对其进行分析。结果VCI患者的全脑MD和FA直方图与正常志愿者不同。与正常对照比较,VCI患者平均全脑FA直方图示峰位置左移、平均FA值降低(P=0.008),MD直方图右移、平均MD值增高(P=0.026),峰位置增高(P=0.041),峰高降低(P=0.002)。平均FA值(r=-0.486,P=0.036)、FA峰高(r=0.498,P=0.030)和FA峰位置(r=-0.641,P=0.003)与MMSE评分相关。结论VCI的患者存在脑扩散异常,DTI直方图部分指标可以帮助评价认知功能损害的严重程度。 相似文献
62.
Jonathan Parke Mark D. Griffiths Adrian Parke 《International journal of mental health and addiction》2007,5(1):39-52
Background Research has demonstrated that optimism and “positive illusions” can be used a coping mechanism among those facing adversity.
Gamblers are a little studied group who also experience adversity and uncertainty. They often feel considerable levels of
frustration, guilt, anger and a sense of feeling cheated after making significant losses. In order to deal with such feelings
it is hypothesized that these individuals will search for positive consequences from their behaviour in order to offset this
negative affect.
Objectives To (1) determine whether after gambling, gamblers compensate and reduce negative affect by identifying positive consequences
from experiencing a loss, and (2) identify types of strategies which gamblers employ and consider how these should be classified.
Materials and Methods Eighty-seven regular slot machine gamblers were interviewed in a variety of environments housing slot machines. Each participant
was asked a series of questions in a semi-structured format, to explore possible styles of positive thinking.
Results Nine types of ‘positive thinking’ experienced by gamblers were identified. These included Comparative thinking, Prophylactic thinking, Biased frequency thinking, Responsibility avoidance, Chasing Validation, Prioritization,
Resourcefulness, Thoughtfulness, and Fear Reduction. Gamblers who were positive thinkers experienced significantly less guilt than non-positive thinkers.
Conclusions While reduction of negative affect may be perceived as positive in many other contexts, it is argued that it may counteract
efforts to promote responsible gambling. Clinical implications and directions for future research are discussed. 相似文献
63.
64.
J C Henry T van Amelsvoort R G Morris M J Owen D G M Murphy K C Murphy 《Neuropsychologia》2002,40(5):471-478
Velo-cardio-facial syndrome (VCFS) is associated with deletions on the long arm of chromosome 22, mild intellectual disability, poor social interaction and a high prevalence of psychosis. However, to date there have been no studies investigating the neuropsychological functioning of adults with VCFS. We compared 19 adults with VCFS with 19 age, gender and IQ matched controls using a comprehensive neuropsychological battery. Compared to controls, adults with VCFS had significant impairments in visuoperceptual ability (Visual Object and Space Perception Battery), problem solving and planning (Tower of London) and abstract and social thinking (Comprehension WAIS-R). It is likely that haploinsufficiency (reduced gene dosage) of a neurodevelopmental gene or genes mapping to chromosome 22q11 underlies the cognitive deficits observed in individuals with VCFS. 相似文献
65.
66.
The motor impairing effects and plasma concentrations of barbital and lorazepam were studied in the alcohol tolerant (AT) and alcohol non-tolerant (ANT) rat lines developed for low and high sensitivity to motor impairment from ethanol. The mixed (M) line, from which the AT and ANT rats were derived, was also included in the study. Like ethanol, barbital and lorazepam impaired the performance of the ANT rats more than that of the AT rats. The motor performance of the M rats was relatively more impaired after barbital than after lorazepam administration at the same dose used in the AT and ANT rats. At the two latter time points (2.5 and 3.5 h) the sensitive ANT rats had significantly higher serum barbital concentrations than the AT rats. The serum barbital concentrations of the AT and ANT rats did not differ, however, at the two first time points (0.5 and 1.5 h) of the tilting plane tests, although the ANT rats were significantly more intoxicated. The concentrations of lorazepam in plasma do not explain the differential motor impairment either, since the sensitive ANT rats had lower plasma concentrations than the insensitive AT rats. The results, thus, suggest that the selection involved in the development of the AT and ANT lines has not been specific for ethanol. The results also support the idea that ethanol, barbiturates and benzodiazepines have some modes of action in common. 相似文献
67.
The Effect of Antiepileptic Drugs on Cognition: Patient Perceived Cognitive Problems of Topiramate versus Levetiracetam in Clinical Practice 总被引:1,自引:0,他引:1
Hans-Peter R. Bootsma †Albert P. Aldenkamp Leonie Diepman Jacques Hulsman Danielle Lambrechts Loes Leenen Marian Majoie Ad Schellekens †Marc de Krom 《Epilepsia》2006,47(S2):24-27
Summary: Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
68.
目的提出对学习策略和教学方式的改进建议。方法测试口腔医学生的场依存/独立认知风格,并用统计学方法分析其与口腔正畸学学习成绩的关系。结果①场独立认知风格是口腔医学专业学生认知风格的主体;②不同性别口腔医学专业学生的场依存/独立认知风格无显著性差异;③学生场依存/独立认知风格与口腔正畸学理论考试成绩有负相关倾向,与口腔正畸学实习操作成绩有正相关倾向。结论学习策略和教学方式因受认知风格的影响而制约学生学习的效果。 相似文献
69.
Sara Jo Nixon Austin L. Errico Oscar A. Parsons William R. Leber Cynthia J. Kelley 《Alcoholism, clinical and experimental research》1992,16(5):949-954
This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states. 相似文献
70.
An 8-year longitudinal study of elderly people has provided data concerning age-associated impairment (AAMI). In 1985 a random sample of 146 persons aged 65 years or more, living in their own homes, were assessed using the Guild Memory Test the Mini–Mental State Examination (MMSE) and other ratings. After excluding 21% of the sample because they scored less than 24 on the MMSE, and another 34% who fulfilled other exclusion criteria, some 48% of the remainder (22% of the total sample) clearly fulfilled NIMH criteria for AAMI and a further 36% (16% of the total sample) were recorded as forgetful. The NIMH criteria are appropriate for certain research purposes but not in assessing prevalence of memory disorders. Follow–up interviews were conducted after 2, 4, 6 and 8 years. The mortality rate and development of dementia among those fulfilling criteria for AAMI appeared similar to the other non-demented groups of subjects; the mortality rate of those with MMSE scores below 24 was significantly higher. Guild test results at 2-yearly intervals showed considerable changes; half of those scoring least well who were retested showed improvement. 相似文献