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161.
Wang YJ Lu J Wu DM Zheng ZH Zheng YL Wang XH Ruan J Sun X Shan Q Zhang ZF 《Neurobiology of learning and memory》2011,96(2):156-165
Evidence indicates that systemic administration of lipopolysaccharide (LPS) induces brain inflammation, ultimately resulting in cognitive deficits. Ursolic acid (UA), a plant-derived pentacyclic triterpenoid, is well known to possess multiple biological functions, including antioxidant, anti-tumor and anti-inflammatory activities. In the present study, we assessed the protective effect of UA against the LPS-induced cognitive deficits in mice. We found that UA significantly improved cognitive deficits of LPS-treated mice in open field, step-through passive avoidance and Morris water maze tasks. One potential mechanism of this action was attributed to the decreased production of pro-inflammatory markers including COX-2, iNOS, TNF-α, IL-1β, IL-2 and IL-6 in LPS-treated mouse brain. Mechanistically, UA markedly inhibited LPS-induced IκBα phosphorylation and degradation, NF-κB p65 nuclear translocation and p38 activation in mouse brain, but did not affect the activation of TLR4, MyD88, ERK, JNK and Akt. Taken together, these results suggest that UA may be useful for mitigating inflammation-associated brain disorders by inhibiting pro-inflammatory factors production, at least in part, through blocking the p38/NF-κB signaling pathways. 相似文献
162.
163.
Portin R Kovala T Polo-Kantola P Revonsuo A Müller K Matikainen E 《Scandinavian journal of psychology》2000,41(1):31-40
The study evaluated the off-line relationship of attention, memory and other cognitive performances with the auditory event-related potentials P3 (P300) and N2. The sample comprised 200 middle-aged construction workers. Verbal, visuomotor and memory tests were administered. Attentional domains were examined using CogniSpeed software. Slowed reaction times in the test of sustained attention (vigilance) were associated with delayed P3 latency (p < 0.001) and decreased P3 amplitude (p = 0.005), as well as with delayed N2 latency (p < 0.001). Visuomotor slowing in Digit Symbol was also related to delayed P3 latency (p = 0.030) and decreased P3 amplitude (p = 0.014). In contrast, mild cognitive impairment, short- and long-term memory, and concentrating or sharing attention with high working memory demands were not related to P3. The results suggest that P3 is linked to attentional performance with low working memory demands rather than to effortful working memory updating, retrieval from memory stores, or mild cognitive impairment. 相似文献
164.
Evoked potential studies have demonstrated that musicians have the ability to distinguish musical sounds preattentively and automatically at the temporal, spectral, and spatial levels in more detail. It is however not known whether there is a difference in the early processes of auditory data processing of musicians. The most emphasized and studied early process, especially for neuropsychiatric purposes, is sensory gating. The suppression percentage of the midlatency auditory evoked potential P50, and rarely the N100, wave is used for sensory gating studies. Our aim in this study was to investigate whether there was a difference in the auditory P50 and N100 suppression of control subjects who were professional musicians with no psychiatric problems. 34 professional musicians and 19 non-musicians (the control group) were included in this study. P50 and N100 measurements were taken, the suppression percentage of P50 and N100 was calculated and the results compared. Musicians showed significantly less P50 suppression when compared to non-musicians. There was no significant difference for N100 suppression. What the decreased P50 suppression in musicians when compared to non-musician subjects means, when we also take into account that N100 suppression is not decreased, and how it may contribute to the music perception and production processes of these persons is discussed. 相似文献
165.
A.J.P. Hendrikx 《Acta psychologica》1984,57(3):193-214
In three experiments, temporal properties of memory retrieval are studied. Latency of positionally probed recall of a single item is measured as a function of its serial position (SP) in a serial list. The requested SP is indicated by a positional probe, presented immediately after the list. For two organizational structures of the list (i.e., grouped vs. ungrouped lists) the experiments study the effects of precueing the probe position briefly before probe presentation, the cue signal indicating the SPs relevant for recall. The problem of confounded effects on latency of requested SP and of probe-signal location is also investigated. A bow-shaped SP-curve is found for ungrouped lists; precueing reduces RT but does not affect the bowed shape. This argues against selective confounding effects of spatial probe position and also suggests that precueing preactivates memory access. Grouping the items into two sublists eliminates precueing effects for items around the group boundary. Furthermore, precueing is detrimental when SPs at opposite ends of the list are precued. This suggests that the available points of memory access can only be utilized one at a time, so that precueing is not beneficial when the item cannot be reached via the preactivated point. Although the notion of single access to memory is in accord with both positional cueing theory and non-associative hierarchical theories (e.g., Estes 1972), various details of the results are in favor of the first type of explanation. 相似文献
166.
167.
Stimulus control, a behavioral technique designed to reduce sleep difficulties, has been demonstrated to be effective when compared with control procedures. These comparisons, mainly involving between-subjects analyses, have neglected the contribution of the stimulus control procedure to the production of clinically significant amelioration of sleep dysfunction. In contrast, the present within-subjects experiment was conducted to assess the capability of stimulus control to produce clinically relevant reductions in multiple measures of sleep disturbance. A comparison with the credible placebo procedure indicated that the stimulus control techniques reduced subjects' sleep onset latency to a mean latency below 30 min per week. Additionally, sedative-hypnotic usage was greatly reduced. 相似文献
168.
This work presents a new conceptualization of the contrast between holistic and differentiated perception of multidimensional stimuli. Specifically, two hypotheses about the experiential status of dimensions within holistic perception are proposed and tested as explanations of young children's general perceptual mode and adults' integral mode. The major result is that three levels of dimensional status are realized: (1) the hypothesis of nonprimary axes characterizes adult “integral” perception of saturation and brightness relations, (2) the hypothesis of primary but not mandatory axes characterizes kindergarteners' “integral” perception of size and shade relations, and (3) the notion of mandatory axes characterizes adults' separable perception of size and shade relations. These results indicate a new interpretation of the integrality-separability distinction and the derivative developmental hypothesis. It is specifically hypothesized that the developmental history of most dimensional combinations includes these three levels. 相似文献
169.
Linda S Gottfredson 《Journal of Vocational Behavior》1978,13(2):210-221
The composition of employment was examined using 1970 census data for employed civilians, Holland's occupational typology, and a prestige scale. The present report extends earlier examinations of the labor force using these dimensions by studying the sex and race composition of types of work at several levels of prestige, and by examining the extent of government employment among men and women in different jobs. Results indicate areas where women and blacks are under- and over-represented. In addition, because of the association between type of work and prestige level, aspirations or interest in a type of work may have implications for the level of work that is available. Counseling and research implications of the results are discussed. 相似文献
170.