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71.
This paper aims to offer an overview of the meaning of autonomy for biological individuals and artificial models rooted in a specific perspective that pays attention to the historical and structural aspects of its origins and evolution. Taking autopoiesis and the recursivity characteristic of its circular logic as a starting point, we depart from some of its consequences to claim that the theory of autonomy should also take into account historical and structural features. Autonomy should not be considered only in internal or constitutive terms, the largely neglected interactive aspects stemming from it should be equally addressed. Artificial models contribute to get a better understanding of the role of autonomy for life and the varieties of its organization and phenomenological diversity.  相似文献   
72.
Liver disease can lead to serious impairment in cognitive functioning, through the development of a condition known as hepatic encephalopathy (HE). While gross impairment is clinically obvious, milder variants of the condition may escape detection at bedside examination and yet may have a significant impact on day-to-day activities. In this brief review article, the neuropsychology of liver disease is examined, focusing on nature, aetiology and significance. The possible contributory role of endogenous benzodiazepines in HE is described, as is the evidence regarding the effect of benzodiazepine antagonism on cognitive functioning in HE. The functional localisation of HE is briefly reviewed, as is the use of neuropsychological measures to evaluate treatment efficacy, e.g. following shunt procedures or liver transplantation. Finally, living donor liver transplantation is described, and the case is made for rigorous longitudinal neuropsychological evaluation of potential donors and recipients. Special issue article in honor of George Fink.  相似文献   
73.
Synopsis Foraging butterflyfishes follow predictable paths as they swim from one food patch to another within their territories and home ranges. The pattern is repeated throughout the day. The behavior is described in species belonging to the coral feeding guild. Habit formation and spatial learning are implicated. Foraging paths are based on learned locations of route specific landmarks. When a coral head is removed the fish look for it in its former location. If pairs of foraging fish are deflected from the path, they resume their routine pattern at the first landmark they encounter. Periodically, fish make excursions of 30 m or more to distant parts of the reef. Usually they follow different paths on the outbound and homeward legs of these excursions. The critical question is: Are the paths novel? If they are, it is evidence for the use of cognitive maps. Certainly fishes living in the highly structured coral reef environment are prime candidates to use cognitive maps in their orientation behavior.  相似文献   
74.
Abstract: In Alzheimer's disease (AD) there are dramatic reductions in human corticotropin-releasing factor (hCRF) concentration and reciprocal increases in CRF receptor density in the cortex. hCRF-binding protein (hCRF-BP), hCRF/hCRF-BP complex, and "free" hCRF were measured in 10 brain regions from control and AD postmortem human tissue. In the control brains hCRF-BP was heterogenously distributed and levels were at least 10-fold higher on a molar basis than total hCRF levels, suggesting that one major role of the binding protein is to limit the actions of hCRF at the hCRF receptors. Concordant with this hypothesis, the percentage of total hCRF that was in the bound inactive form ranged from 65 to 90% in most areas examined, with the exception of the caudate and globus pallidus where only 15 and 40% were complexed, respectively. hCRF-BP concentrations were similar in the control and AD groups except for Brodmann area (BA) 39 where there was a small but significant decrease in the AD group. Complexed hCRF levels were significantly decreased in BA 8/BA 9, BA 22, BA 39, nucleus basalis, and globus pallidus in the Alzheimer's group and free hCRF levels were significantly decreased only in three brain areas, BA 4, BA 39, and caudate; substantial (40%) but nonsignificant decreases were also noted in BA 8/BA 9 and BA 22. These data demonstrate that (1) a large proportion of the total hCRF in human brain is complexed to hCRF-BP and thus unavailable for hCRF receptor activation, (2) reductions in total hCRF alone do not necessarily predict reductions in bioactive free hCRF, and (3) total hCRF levels and hCRF-BP levels appear to be the main factors determining the quantity of bound and free hCRF in human brain.  相似文献   
75.
The traditional Mediterranean diet (MedDiet) has shown beneficial effects on cognitive decline. Nevertheless, diet–gene interactions have been poorly evaluated. We aimed to investigate diet–gene interaction in the PREDIMED-NAVARRA randomized trial. A total of 522 participants (67 ± 6 years at baseline) enrolled in the PREDIMED-NAVARRA trial were randomly allocated to one of three diets: two MedDiets (supplemented with either extra-virgin olive oil or nuts) or a low-fat diet. They were evaluated with the Mini-Mental State Examination (MMSE) and the Clock Drawing Test (CDT) after 6.5 years of intervention. Subjects were genotyped for CR1-rs3818361, CLU-rs11136000, PICALM-rs3851179 and Apolipoprotein E (ApoE) genes. We studied MedDiet–gene interactions for cognition and assessed the effect of the MedDiet on cognition across different genetic profiles. A significant interaction (p = 0.041) between CLU-rs11136000 and the MedDiet intervention on the MMSE was found with a beneficial effect of MedDiet among carriers of the T minor allele (B = 0.97, 95 % CI 0.45–1.49). Similar effect was observed for CR1-rs3818361, but no significant interaction was observed (p = 0.335). For PICALM-rs3851179, the MedDiet intervention showed a beneficial effect in both genotype groups. No apparent interaction was found for the CDT between intervention and gene variants. Similarly, participants randomly allocated to MedDiet groups, with favorable profiles of CR1, CLU and PICALM genes, significantly improved CDT scores compared to controls with the same genetic profile. Cognitive performance was better for non-ApoE4 and for ApoE4 carriers of MedDiet groups compared to controls, but for CDT performance, we only found statistical significant differences for non-ApoE4 carriers. A MedDiet intervention modulates the effect of genetic factors on cognition. The effect of MedDiet might be greater for subjects with a more favorable genetic profile.  相似文献   
76.
Comprehensive structure activity relationship (SAR) studies were conducted on a focused screening hit, 2-(methylthio)-3-(phenylsulfonyl)-4H-pyrido[1,2-a]pyrimidin-4-imine (1, IC50: 4.0 nM), as 5-HT6 selective antagonists. Activity was improved some 2–4 fold when small, electron-donating groups were added to the central core as observed in 19, 20 and 26. Molecular docking of key compounds in a homology model of the human 5-HT6 receptor was used to rationalize our structure–activity relationship (SAR) findings. In pharmacokinetic experiments, compound 1 displayed good brain uptake in rats following intra-peritoneal administration, but limited oral bioavailability.  相似文献   
77.
Estimating the functional interactions and connections between brain regions to corresponding process in cognitive, behavioral and psychiatric domains is a central pursuit for understanding the human connectome. Few studies have examined the effects of dynamic evolution on cognitive processing and brain activation using brain network model in scalp electroencephalography (EEG) data. Aim of this study was to investigate the brain functional connectivity and construct dynamic programing model from EEG data and to evaluate a possible correlation between topological characteristics of the brain connectivity and cognitive evolution processing. Here, functional connectivity between brain regions is defined as the statistical dependence between EEG signals in different brain areas and is typically determined by calculating the relationship between regional time series using wavelet coherence. We present an accelerated dynamic programing algorithm to construct dynamic cognitive model that we found that spatially distributed regions coherence connection difference, the topologic characteristics with which they can transfer information, producing temporary network states. Our findings suggest that brain dynamics give rise to variations in complex network properties over time after variation audio stimulation, dynamic programing model gives the dynamic evolution processing at different time and frequency. In this paper, by applying a new construct approach to understand whole brain network dynamics, firstly, brain network is constructed by wavelet coherence, secondly, different time active brain regions are selected by network topological characteristics and minimum spanning tree. Finally, dynamic evolution model is constructed to understand cognitive process by dynamic programing algorithm, this model is applied to the auditory experiment, results showed that, quantitatively, more correlation was observed after variation audio stimulation, the EEG function connection dynamic evolution model on cognitive processing is feasible with wavelet coherence EEG recording.  相似文献   
78.
目的:了解不同性别冠心病(CAD)患者对于急性心肌梗死(AMI)相关症状的认知情况,为有效缩短AMI院前延误(PHD)提供依据。方法:于2015年10月至2016年3月在同济大学附属同济医院和上海市闸北区中心医院心内科门诊及病房,对确诊为CAD的受访者进行调查,收集受访者的一般资料,要求受访者区分胸痛、呼吸困难、出汗、恶心呕吐、晕厥是否为AMI相关症状。使用多元回归分析的方法,分析不同性别患者对上述症状的认知情况。结果:共680例CAD患者自愿接受调查,男性受访者对多数AMI相关症状的知晓率普遍高于女性。性别组间比较的多因素Logistic回归分析显示,相比较于女性,男性CAD患者对AMI相关症状出汗,恶心呕吐、晕厥认知度的OR值分别为1.41(1.04-2.41)、1.79(1.09-2.95)、1.96(1.42-2.72)。结论:不同性别患者对AMI相关症状认识水平存在差异,女性在出汗,恶心呕吐,晕厥不典型AMI相关症状认识程度较男性差。应加强对该人群的健康教育,以最大可能的缩短决策延误时间。  相似文献   
79.
Phosphatidylserine (PS) is the major anionic phospholipid class particularly enriched in the inner leaflet of the plasma membrane in neural tissues. PS is synthesized from phosphatidylcholine or phosphatidylethanolamine by exchanging the base head group with serine, and this reaction is catalyzed by phosphatidylserine synthase 1 and phosphatidylserine synthase 2 located in the endoplasmic reticulum. Activation of Akt, Raf-1 and protein kinase C signaling, which supports neuronal survival and differentiation, requires interaction of these proteins with PS localized in the cytoplasmic leaflet of the plasma membrane. Furthermore, neurotransmitter release by exocytosis and a number of synaptic receptors and proteins are modulated by PS present in the neuronal membranes. Brain is highly enriched with docosahexaenoic acid (DHA), and brain PS has a high DHA content. By promoting PS synthesis, DHA can uniquely expand the PS pool in neuronal membranes and thereby influence PS-dependent signaling and protein function. Ethanol decreases DHA-promoted PS synthesis and accumulation in neurons, which may contribute to the deleterious effects of ethanol intake. Improvement of some memory functions has been observed in cognitively impaired subjects as a result of PS supplementation, but the mechanism is unclear.  相似文献   
80.
目的调查肿瘤科护士预防导管相关性血流感染(CRSBI)的认知与行为情况。方法采用方便抽样法,应用自行设计的"预防CRSBI认知与行为问卷"对107名肿瘤科在职护士进行调查,并进行结果分析。结果 107名护士预防CRSBI知识得分20~105分,平均得分(54.95±14.77)分,平均正确率52.34%。预防CRSBI操作行为得分25~45分,平均得分(39.72±4.26)分。肿瘤科护士预防CRSBI认知情况与工作年限、技术职称和是否接受过CRSBI的知识培训有关,行为情况与是否接受过CRSBI的知识培训有关。结论应加强肿瘤科护士CRSBI相关知识的培训和考核,加强管控,进一步提高肿瘤科护士预防CRSBI的认知水平。  相似文献   
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