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BACKGROUND: Cognitive impairment is associated with functional impairment in patients with Alzheimer's disease (AD). Behavioural disturbance is very common in these patients. Nevertheless, there has been very little research into the relations between behavioural disturbance and functional status in AD. The purpose of this study is to investigate the relationship between behavioural disturbance and functional status after taking account of cognitive impairment. MATERIAL AND METHODS: 579 patients were prospectively evaluated at 16 French hospitals, all referents for AD, and were diagnosed with possible or probable AD. These patients were assessed with NeuroPsychiatric Inventory (NPI), cognitive subscales of the Alzheimer's Disease Assessment Scale (ADAS-cog), Clinical Dementia Rating scale (CDR) and Instrumental Activities of Daily Living scale (IADL). RESULTS: The number of men with available data for IADL total score was too small to make any analysis. 'Group A' gathered 256 women for whom the relation between autonomy for Activities of Daily Living (ADL) and the other variables were determined. 'Group B', pooled 85 women for whom relations found were verified. Linear regression was used for the analysis. With age, cognitive impairment allows us to explain best (38%) the loss of autonomy for ADL. CONCLUSION: The role of behavioural disturbances in the loss of autonomy for ADL was not determinant in our study, whereas cognitive impairment and age were better able to determine the loss of autonomy for ADL. Further study is needed to explain the decline of functional status in AD patients.  相似文献   
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Behavioral and Psychological Symptoms are major and frequent manifestations of Alzheimer's Disease (AD). The aim of the present study was to evaluate neuropsychiatric symptoms in the PHRC REAL.FR cohort (for Réseau sur la maladie d'Alzheimer Fran?ais) after one year of evolution. Four hundred and eighty two patients with mild and moderate AD were assessed. A majority of them had significant symptoms at inclusion (85.3 % of subjects with mild AD, 89.7% of patients with a moderate AD). Patients with mild AD had a significant increase of the Neuropsychiatric Inventory (NPI) frequency x severity scores for apathy and aberrant motor behavior. Patients with moderate AD had a significant increase of NPI disinhibition, aberrant motor behavior and sleep disorders scores. The variation of NPI total score at one year correlated positively with change in Zarit's caregiver burden score, independently of global cognitive evolution. After one year, a group of 54 patients were institutionalized in nursing home or long term care unit. When compared to non institutionalized patients, the institutionalized group was characterized at base line by a lower MMSE score, a higher Zarit caregiver burden score, and a higher NPI agitation and disinhibition scores.  相似文献   
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The role of the circadian clock system in nutrition and metabolism   总被引:1,自引:0,他引:1  
Mammals have an endogenous timing system in the suprachiasmatic nuclei (SCN) of the hypothalamic region of the brain. This internal clock system is composed of an intracellular feedback loop that drives the expression of molecular components and their constitutive protein products to oscillate over a period of about 24?h (hence the term 'circadian'). These circadian oscillations bring about rhythmic changes in downstream molecular pathways and physiological processes such as those involved in nutrition and metabolism. It is now emerging that the molecular components of the clock system are also found within the cells of peripheral tissues, including the gastrointestinal tract, liver and pancreas. The present review examines their role in regulating nutritional and metabolic processes. In turn, metabolic status and feeding cycles are able to feed back onto the circadian clock in the SCN and in peripheral tissues. This feedback mechanism maintains the integrity and temporal coordination between various components of the circadian clock system. Thus, alterations in environmental cues could disrupt normal clock function, which may have profound effects on the health and well-being of an individual.  相似文献   
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目的:总结胰岛移植过程中胰岛培养的研究现状,为利用胰岛培养准备更多更好的胰岛提供理论依据和技术支持。资料来源:以计算机检索Medline和Pubmed数据库1994-01/2007-01与胰岛培养相关的文章,检索词为“isle,tculture”,限定文章语言种类为English。同时计算机检索CNKI中国全文数据库1994-01/2007-01与胰岛培养相关的文章,检索词为“胰岛,培养”,限定文章语言种类为中文。资料选择:对资料进行初审,纳入标准:①与胰岛培养相关的文章。②1994年以后发表的文章。排除标准:Meta分析类文章。资料提炼:共检索到1384篇与胰岛培养相关的文章,入选33篇。对所检索文章的相关信息加以综合概括,其中关于胰岛培养中基础培养基、培养添加物、培养温度、密度等方面的文章18篇,关于胰岛培养新尝试的文章12篇。资料综合:将胰岛培养后再行移植有一定优势,包括降低免疫原性和为术前准备赢得时间等。目前对于挑选合适培养基及其添加物,调整合适培养温度、培养密度以及保护胰岛的活性等都有了比较深入细致的研究;同时很多学者开始尝试一些新的方法延长胰岛培养时间,改善胰岛功能,包括加入细胞外基质、与其他细胞共培养、选用微重力系统培养以及利用胶囊包裹培养等均显示良好的效果。结论:虽然胰岛培养可能会影响胰岛的活性和功能,但随着对胰岛生理和病理生理特性研究的深入,新的技术方法可将这些影响降到最低。胰岛培养给临床实践带来的便利是其最大的优势,加强胰岛培养的研究与应用有着重要的意义。  相似文献   
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Background  

Breast tissue expression of the ERBB proto-oncogene family has been extensively studied. It was recently shown that expression of epidermal growth factor receptor (EGFR; c-erbB-1) and epidermal growth factor receptor (HER)2 (c-erbB-2) can be detected in the serum of breast cancer patients. The clinical relevance of this has not been fully established.  相似文献   
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Recent studies have suggested that the adipocyte-derived hormone, leptin, plays a role in the regulation of metabolism. Here, we tested this hypothesis in the seasonally breeding Siberian hamster, as this species exhibits profound seasonal changes in adiposity and circulating leptin concentrations driven by the annual photoperiodic cycle. Male hamsters were kept in either long (LD) or short (SD) photoperiods. Following exposure to short photoperiods for 8 weeks animals exhibited a significant weight-loss and a 16-fold reduction of serum leptin concentrations. At Week 9, animals in both photoperiods were infused with leptin or PBS via osmotic mini-pump for 14 days. Chronic leptin infusion mimicked LD-like concentrations in SD-housed animals and caused a further decline in body weight and adipose tissue. In LD-housed animals, leptin infusion resulted in a significant elevation of serum concentrations above natural LD-like levels, but had no discernable effect on body weight or overall adiposity. Both bending and compression characteristics and histomorphometric measurements of trabecular bone mass were unaltered by leptin treatment or photoperiod. Our data therefore show that despite a high natural amplitude cycle of leptin, this hormone has no apparent role in the regulation of bone metabolism, and therefore do not support recent propositions that this hormone is an important component in the metabolism of bone tissue.  相似文献   
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胶原海绵复合新生大鼠原代心肌细胞构建工程化心肌组织   总被引:2,自引:2,他引:2  
目的:探索以胶原海绵为支架、新生大鼠原代心肌细胞为种子细胞,于体外构建工程化心肌组织的方法。方法:实验于2005-12/2006-11在解放军第四军医大学西京医院心内科实验室完成。Ⅰ型胶原海绵剪切成方形片状(2.0cm×1.4cm×0.2cm),经60Co照射消毒,于DMEM培养液中水化1h左右。另取1d龄SD大鼠心脏,剪成小碎块,然后用2.5g/L胰蛋白酶于37℃中消化,吸取上清至含胎牛血清的DMEM中,重复消化四五次,用差速贴壁法除去大部分成纤维细胞,将细胞沉淀用DMEM培养液以2×109L-1的密度悬浮备用。将上述的心肌细胞悬液1mL缓慢滴注于玻璃模型中的胶原海绵上,然后置于细胞培养中培养。肉眼及显微镜主要观察工程化心肌组织在培养期间的自发收缩情况,包括收缩的部位、强度、频率、一致性以及收缩随时间变化的情况。苏木精-伊红染色观察工程化心肌组织内胶原纤维的变化,细胞形态,胞核的形状及细胞之间的连接。免疫组织化学染色和透射电镜观察工程化心肌组织片的形态和功能。结果:①细胞接种于胶原海绵上1d后,细胞/胶原复合物的凝胶化过程基本完毕,体积保持恒定,维持至培养结束,第3天细胞/胶原复合物局部出现点片状自发收缩,第5天整个细胞/胶原复合物出现同步化自发收缩,收缩频率61~199次/min。2周后37.5%的工程化心肌组织的自发收缩活动减弱,但75%的工程化心肌组织的自发收缩活动持续至培养结束。②苏木精-伊红染色、免疫组织化学染色和透射电子显微镜显示,工程化心肌组织内细胞间连接广泛存在,细胞多呈纵向分布,胞核呈长圆形,胞浆内α-肌节肌动蛋白阳性,胞内肌原纤维排列整齐,可见到心肌特异性的肌小节结构和Z线,多数细胞具有分化的心肌细胞表型。结论:用新生大鼠原代心肌细胞为种子细胞、以Ⅰ型胶原海绵为支架材料,构建出的工程化心肌组织,于体外可长时间持续自发收缩,该细胞/胶原复合物的形态结构与生理功能均类似于成熟大鼠心肌组织。  相似文献   
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