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971.
The conceptual structure account (CSA) is a model specifying the role of the living and non-living domain dichotomy in the structure of semantic memory. According to this model, feature distinctiveness and the perceptual–functional inter-correlation of concepts are assumed to play a major role in impairing the ability to discriminate between living and non-living concepts in Alzheimer’s disease (AD). The hypothesis was tested in this study by using naming and sorting tasks traditionally considered as assessing distinctiveness, and a property verification task where distinctiveness and perceptual–functional inter-correlation were objectively controlled against norms especially created for this purpose. Alzheimer’s patients (n = 59) with minimal, mild or moderate dementia and normal elderly adults (n = 31) participated in the study. Overall, the findings did not support the CSA predictions. They revealed a distinctiveness effect on response accuracy with shared features dominating distinctive features regardless of domain. They also revealed more difficulties in the tasks involving effortful processes. The results stress the need to consider both cognitive demands of tasks and structural aspects of knowledge in the evaluation of semantic memory in AD.  相似文献   
972.
We studied 54 patients with hypoxemic chronic obstructive pulmonary disease (COPD). The Mini Mental State Examination and the Mental Deterioration Battery were used for neuropsychological assessment. Heart rate variability (HRV) was assessed based on 24-h Holter ECG recording. Mann–Whitney test was used to compare HRV parameters of patients performing normally or abnormally on individual neuropsychological tasks. Spearman’s rho was used to investigate the correlations between HRV parameters and neuropsychological scores, indexes of health status or COPD severity. Patients with defective performance at copying drawings with landmarks (CDL) test (N = 23) had lower very low frequency (VLF) power with respect to patients with normal performance (N = 31) (24 h: median 213; interquartile range 120–282 vs. 309; 188–431 ms2, p = 0.043; daytime: 202; 111–292 vs. 342; 194–397 ms2, p = 0.039). The CDL score correlated with the VLF power (24 h: ρ = 0.27, p = 0.049; daytime: ρ = 0.30, p = 0.028), and the normalized low frequency/high frequency (LF/HF) ratio (24 h: ρ = 0.27, p = 0.05; daytime: ρ = 0.33, p = 0.015). Sympathetic modulation decreased for increasing severity of COPD. In conclusion, drawing impairment correlates with depressed sympathetic modulation in patients with COPD, and both might be indexes of COPD severity.  相似文献   
973.

Background

Decreased speed of information processing is a hallmark of Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Recent studies suggest that response speed (RS) measures are very sensitive indicators of changes in longitudinal follow-up studies. Insight into the psycho-physiological underpinnings of slowed RS can be provided by measuring the associated event-related potentials (ERP).

Aims

The current study aims to investigate the relation between RS and its psycho-physiological correlates in AD and MCI.

Methods

Fifteen psychoactive drug-naïve AD patients, 20 MCI patients and twenty age-matched, healthy control subjects participated. Response speed was measured during a simple (SRT) and choice reaction time task (CRT). An oddball and contingent negative variation (CNV) paradigm were used to elicit ERP. To evaluate test-retest reliability (TRR), subjects underwent a similar assessment one week after the first.

Results

The SRT and CRT distinguished the patient groups significantly. The P300 amplitude and latency also distinguished the groups and showed a significant correlation with response speed. The CNV amplitude did not reveal a significant difference between groups and also showed a low TRR.The TRR of the SRT, CRT and P300 amplitude and latency in general was moderate to high.The current study suggests that response speed measures on a behavioural and psycho-physiological level deserve attention as a possible marker in the diagnosis and follow-up of AD.  相似文献   
974.
We investigated the influence of the level of cognitive functioning on sequence-specific learning in Parkinson's disease (PD). This was done by examining the relationship between the scales for outcomes in Parkinson's disease-cognition [SCOPA-COG, Marinus, J., Visser, M., Verwey, N. A., Verhey, F. R. J., Middelkoop, H. A. M.,Stiggelbout, A., et al. (2003). Assessment of cognition in Parkinson's disease. Neurology, 61, 1222-1228] and the serial reaction time (SRT) task [Nissen, M. J., & Bullemer, P. T. (1987). Attentional requirements for learning: Evidence from performance measures. Cognitive Psychology, 19, 1-32] in a homogeneous sample, consisting of 25 PD patients diagnosed in Stage 3 of the Hoehn and Yahr [Hoehn, M. M., & Yahr, M. D. (1967). Parkinsonism: onset, progression, and mortality. Neurology, 17, 427-442] scale. Six patients in the low scoring cognitive group, 11 patients in the average scoring and eight patients in the high scoring group, conducted a SRT task with a deterministic sequence. Sequence-specific learning was assessed by inserting a random block to determine whether the acquisition of sequence movements differed between groups. Our results indicate an association between cognitive functioning in PD patients and sequence learning. These findings emphasize the use of assessing cognition in addition to the well-known motor aspects in PD.  相似文献   
975.
Focal lacunar infarctions due to cerebral small vessel atherosclerosis or single/multiple large cortical infarcts lead to vascular dementia, and different genes and environmental factors have been implicated in causation or aggravation of the disease. Previous reports suggest that some of the risk factors may be common to both vascular as well as degenerative dementia. Among genetic factors, role of angiotensin converting enzyme (ACE) and methylene-tetrahydrofolate reductase (MTHFR) genes as putative risk factors has been examined but the outcome of these studies remain inconclusive. Present study attempted to see the importance of ACE alu insertion/deletion and MTHFR C677T polymorphisms as genetic predisposers to dementia. The study comprised of 80 vascular dementia patients, 90 degenerative dementia patients and 170 age matched controls. All were genotyped for ACE, MTHFR and APOE polymorphisms using PCR-RFLP method. Frequency of ACE D allele was seemingly high in dementia cases (26.7%) when compared to controls (11.2%). However, after adjusting for age and APOE E4*, none of the ACE alleles showed good correlation. MTHFR genotypes or alleles also did not show any correlation. Our study suggests no true correlation of ACE or MTHR genes with dementia in elderly.  相似文献   
976.
Methods of mindfulness are gaining increasing popularity within the behavioral and cognitive therapies and appear helpful for a range of clinical problems. The purpose of this study was to examine cognitive and behavioral processes underlying mindfulness. One hundred fifty patients seeking treatment for chronic pain completed a battery of questionnaires, including the 15-item Mindful Attention Awareness Scale (MAAS; Brown and Ryan, J Pers Soc Psychol 84:822–848, 2003). Preliminary analyses supported reliability and validity of the MAAS for patients with chronic pain. A confirmatory factor analysis provided incomplete support for a singe factor structure from the items of the MAAS. In turn, an exploratory factor analysis yielded a four-factor solution: Acting with Awareness, Present Focus, Responsiveness, and Social Awareness. Correlation and regression analyses indicated that the Acting with Awareness and Present Focus subscales were significantly related to measures of patient emotional, physical, and social functioning. Further research that explores and validates models of mindfulness-based processes is recommended.  相似文献   
977.
针对冠心病和(或)2型糖尿病患者,已有许多有效的防治措施。然而,尽管接受了当前的标准治疗,这类患者仍会反复发生许多大血管和微血管事件,这种现象称之为血管剩留风险。有许多因素影响血管剩留风险的存在,其中最为重要的是致动脉粥样硬化性血脂异常。因此,采取积极的全面干预措施如改善生活方式、联合降脂以改善所有的脂质异常指标,是最大程度降低血管剩留风险的动向。  相似文献   
978.
盆腔炎性疾病(pelvic inflammatory disease,PID)是指女性上生殖道的一组感染性疾病,由于临床不典型和致病微生物的多样性,导致目前临床上PID的诊断和治疗有一定的难度。本文介绍PID发病机制、高危因素、后遗症和并发症等方面的研究进展,推荐其诊断和治疗的最新规范。  相似文献   
979.
盆腔炎是育龄期妇女的常见病和多发病,常见的病原体有细菌、念珠菌、解脲脲原体、沙眼衣原体等。结合临床检测及文献报道,发现年轻女性盆腔炎解脲脲原体感染率较高,是盆腔炎的高发人群。解脲脲原体感染患者合并其他病原微生物感染的情况相当严重。对患者进行全面系统的病原生物检测,对于预防和有效治疗盆腔炎感染十分重要。  相似文献   
980.
西医对盆腔炎的治疗多流于急性期的抗炎治疗,对慢性迁延期并无切实有效的良法。中医对本病有独到见解,具有中药疗法、非药物疗法(针灸)或复合疗法三大疗法,但其治疗中存在的辩证偏向、体质忽略等不足还需解决。  相似文献   
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