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181.
The objective of this study is to investigate cognitive and attentional function in adolescents and young adults with operated congenital heart disease. Previous research has indicated that children with congenital heart disease have deficits in broad areas of cognitive function. However, less attention has been given to survivors as they grow into adolescence and early adulthood. The participants were 18 non-syndromic adolescents and young adults with tetralogy of Fallot and d-transposition of the great arteries that required cardiac surgery before the age of 5 years, and 18 healthy, unaffected siblings (11–22 years of age for both groups). Cases with congenital heart disease and their siblings were administered Wechsler Intelligence scales and reported attention problems using the Achenbach System of Empirically Based Assessments. Cases were compared to both healthy siblings and established norms. Cases performed significantly lower than siblings on full scale IQ and processing speed, and significantly lower than norms on perceptual reasoning. Cases also reported more attention problems compared to both siblings and norms. Effect sizes varied with medium-to-large effects for processing speed, perceptual reasoning, working memory, and attention problems. Findings suggest that neurocognitive function may continue to be affected for congenital heart disease survivors in adolescence and young adulthood, and that comparisons to established norms may underestimate neurocognitive vulnerabilities.  相似文献   
182.
总结了28年共2453篇有关小儿肾小球疾病治疗的文献,发现其发展规律符合科学的发展观药物的选择趋向于疗效肯定而且毒副作用小的药物,新方法新技术不断涌现,药物疗效的评价日趋合理,药物作用机制从系统、器官水平深入到细胞、分子及基因水平,各学科间的合作与联系增加。  相似文献   
183.
184.
Nowadays, intelligent connectionist systems such as artificial neural networks have been proved very powerful in a wide area of applications. Consequently, the ability to interpret their structure was always a desirable feature for experts. In this field, the neural logic networks (NLN) by their definition are able to represent complex human logic and provide knowledge discovery. However, under contemporary methodologies, the training of these networks may often result in non-comprehensible or poorly designed structures. In this work, we propose an evolutionary system that uses current advances in genetic programming that overcome these drawbacks and produces neural logic networks that can be arbitrarily connected and are easily interpretable into expert rules. To accomplish this task, we guide the genetic programming process using a context-free grammar and we encode indirectly the neural logic networks into the genetic programming individuals. We test the proposed system in two problems of medical diagnosis. Our results are examined both in terms of the solution interpretability that can lead in knowledge discovery, and in terms of the achieved accuracy. We draw conclusions about the effectiveness of the system and we propose further research directions.  相似文献   
185.

Background

This study analyzed the presence of awareness of movement disorders (dyskinesias and hypokinesias) in 25 patients with Parkinson’s disease (PD) and motor fluctuations (dyskinesias, wearing off, on–off fluctuations). Of the few studies that have dealt with this topic, none have analyzed the differences in the awareness of motor deficits by comparing the on and off states using motor scales and an extensive battery of tests to assess cognitive and behavioral functioning.

Methods

PD patients were compared on three different scales that we have devised to measure awareness of movement disorders: Global Awareness of Movement (GAM) Disorders, dyskinesia/hypo-bradykinesia rating scales.

Results

Data showed that PD patients had greater awareness and psychological suffering in the off state than in the on state. In particular, they were troubled by motor disabilities related to hypokinesias and had mood-related symptoms and a perception of disability in activities of daily living. Interestingly, patients only showed a selective reduction of awareness of movement disorders associated with executive functions and related to dyskinesias in the on state, compared to a preserved awareness of hypokinesias in the off state. On the contrary, no association with executive functions was found in the off state.

Conclusion

Our findings suggest that the dopaminergic overstimulation of mesocorticolimbic pathways may cause a dysfunction of prefrontal–subcortical connections related to the impaired insight.  相似文献   
186.
重症手足口病的早期识别与处理   总被引:1,自引:0,他引:1  
手足口病(hand-foot-mouth disease,HFMD)是由肠道病毒[以柯萨奇A组16型(Coxsackievirus A16,CoxA16)、肠道病毒71型(Enterovirus 71,EV71)多见]引起的急性传染病,而重症多由EV71感染引起。由于EV71的高度嗜神经性,重症者可合并中枢神经系统(central nervous system,CNS)损害、急性肺水肿/出血等。现就重症手足口病的早期识别与处理进行简要综述。  相似文献   
187.
Patients with mild Alzheimer's disease (AD) display a greater tendency to endorse unstudied items as "old" on memory tests than healthy older adults. This liberal response bias may result in mistaken beliefs about the completion of common tasks. This research attempted to determine whether it was possible to shift the response bias of mild AD patients to be more conservative on a recognition memory test through behavioral intervention. Patients with mild AD and matched controls were evaluated with two almost identical paradigms, separated by about one week. For each session, 30 words were studied and 60 words (half studied, half novel) were shown at test. During one session participants were told that 30% of words were old, and at the other session that 70% were old. We found that both groups were able to shift their response bias between the two conditions. That patients with mild AD were able to successfully shift their response bias demonstrates that--despite their overall liberal response bias and poor memory relative to controls--one component of metamemorial ability is preserved in patients with mild AD.  相似文献   
188.
Two studies explored the stability of art preference in patients with Alzheimer's disease and age-matched control participants. Preferences for three different styles of paintings, displayed on art postcards, were examined over two sessions. Preference for specific paintings differed among individuals but AD and non-AD groups maintained about the same stability in terms of preference judgments across two weeks, even though the AD patients did not have explicit memory for the paintings. We conclude that aesthetic responses can be preserved in the face of cognitive decline. This should encourage caregivers and family to engage in arts appreciation activities with patients, and reinforces the validity of a preference response as a dependent measure in testing paradigms.  相似文献   
189.
While cognitive skill learning is normally acquired implicitly through frontostriatal circuitry in healthy individuals, neuroimaging studies suggest that patients with Parkinson's disease (PD) do so by activating alternate, intact brain areas associated with explicit memory processing. To further test this hypothesis, 10 patients with PD and 12 healthy controls were tested on a modified, learning version of the Tower of London task while undergoing positron emission tomography at four different time points over the course of learning. Despite having less accurate problem solving abilities than controls, PD patients were able to acquire the skill learning task. However, as compared to controls, they maintained higher levels of cerebral blood flow activity in the dorsolateral prefrontal cortex and hippocampus and showed an increase in activity in the frontopolar cortex and posterior cingulate over the course of learning. These findings reflect a shift to the explicit memory system in PD patients, enabling them to learn this cognitive skill, which is normally acquired by control subjects using implicit learning strategies and frontostriatal circuitry.  相似文献   
190.
The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive impairment, 23 with AD and 15 healthy controls underwent high-resolution magnetic resonance imaging. Optimized voxel-based morphometry (VBM) was performed to investigate the putative association between CDT performance and gray matter (GM) density throughout the entire brain. In the first step of analysis (p<.001, uncorrected), VBM revealed a reduced GM density in numerous cortical (temporal lobe, frontal lobe, parietal lobe, cerebellum) and subcortical (thalamus, basal ganglia) brain regions to be associated with poorer CDT performance. When corrected for multiple comparisons (p<.01), the associations remained significant predominantly in the left temporal and--less pronounced--the right temporal lobe. VBM demonstrated CDT performance to depend on the integrity of widely distributed cortical and subcortical areas in both brain hemispheres with accentuation in the left-sided temporal lobe region.  相似文献   
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