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61.
β-Carotene (BC) is a potent dietary source of vitamin A for populations at risk of vitamin A deficiency, yet its bioavailability is influenced by several factors such as dietary fat, carotenoids type, and other components. We hypothesize that type of micellar phospholipids influence bioefficacy of carotenoids and activity of carotenoid metabolizing enzymes. This study determined the BC bioefficacy in rats (n = 5/time point) after an equimolar dose of BC and lutein (Lut) solubilized in micelles containing either phosphatidylcholine (PC) or lysophosphatidylcholine (LPC), or no phospholipid (NoPL). Results show that no BC and Lut was detected in the plasma of rats at 0 hour, but after gavage, the mean (SD) area under the curve (AUC; in picomoles per milliliter) of plasma BC for 6 hours in PC, LPC, and NoPL groups were 1145 (132), 965 (199), and 2136 (112), respectively. The AUC value of plasma Lut in LPC group (183 ± 23 pmol mL−1 h−1) was higher than the other 2 groups. Similarly, liver BC and Lut levels in the LPC group were significantly higher than the other groups. The activity of BC 15,15′-monooxygenase in the intestinal mucosa of LPC and PC groups was higher than NoPL group. Plasma retinyl palmitate level in LPC (AUC, 647 ± 89 pmol mL−1 h−1) group was 2-fold higher than that of PC and NoPL groups. Results indicate that phospholipids enhanced the BC and Lut absorption. β-Carotene uptake was not affected by Lut when given with micellar phospholipids, but reduced plasma Lut level was observed, which may be due to the conversion of absorbed Lut into its metabolites.  相似文献   
62.
Lipids through regulation of chronic inflammation play key roles in the development of various diseases. Here, we report that a mixed population of human primary monocytes migrated towards LPC, as well as oxidized linoleic acid isoforms 9-S-HODE, 9-R-HODE and 13-R-HODE. Incubation with 9-R-HODE, 13-R-HODE and LPC resulted in increased expression of CXCR4, the receptor for SDF-1α/CXCL12, correlated with increased monocyte migration towards SDF-1α/CXCL12. Further, we report increased expression of CCR9, the receptor for TECK/CCL25, after stimulation with these lipids. Upon examining the migratory response towards TECK/CCL25, it was observed that an increase in CCR9 expression upon pre-treatment with 9-S-HODE, 9-R-HODE, 13-R-HODE and LPC resulted in increased migration of monocytes expressing CCR9. Only LPC but not any other lipid examined increased the influx of intracellular Ca2+ in monocytes. Finally, 9-S-HODE, 9-R-HODE, 13-R-HODE, or LPC inhibited the release of IL-6 from monocytes suggesting that these lipids may play important role in controlling inflammatory responses.  相似文献   
63.
介绍一套环境温度监测网络系统,简述其工作原理、基本软硬件构成和网络系统功能。经实验室测试,整个系统工作稳定可靠,具有一定的市场效益和应用前景。  相似文献   
64.
Social comparison is a common behavior that largely determines people’s experience of decision outcome. Previous research has showed that interpersonal relationship plays a pivotal role in social comparison. In the current study, we investigated whether the manipulation of context-based relationship would affect participants’ comparison of self-outcome and other-outcome. Participants first finished a trust game with likeable (dislikeable) partner and then they were involved in a gambling task and observed the outcomes for themselves and for partners. According to self-reports, participants were more satisfied with likeable partner’s gains than losses only when they received gains, but they were always more satisfied with dislikeable player’s losses compared to gains. Event-related potentials including the feedback-related negativity (FRN), P3 and late positive component (LPC) were sensitive to context-based relationship. Specifically, the prediction error signal (indexed by the FRN) was largest when participants received losses but dislikeable player received gains. Meanwhile, the P3 indicates that participants had stronger motivation to outperform dislikeable player. Finally, the LPC was larger when participants received the same outcomes with dislikeable players. In general, our results support the key point of the self-evaluation maintenance model that personal closeness modulates subjective sensitivity when drawing a comparison of one’s outcomes with other’s outcomes.  相似文献   
65.
目的观察通脉宁胶囊不同剂量药物血清对溶血磷脂酰胆碱(LPC)诱导的血管平滑肌细胞增殖活性及细胞周期的影响.方法组织贴块法进行血管平滑肌细胞(VSMC)培养,应用血清药理学的方法,LPC10-8 mol/L作为刺激因子,将通脉宁胶囊分为大、中、小3个剂量组.MTT法测定细胞增殖活性,流式细胞仪检测细胞周期.结果通脉宁大、中、小剂量组可明显降低细胞的OD值呈剂量依赖性地抑制LPC诱导的VSMC增殖. 明显降低细胞的S期数目百分比,增加G0/G1期数目百分比,使VSMC阻滞在G0/G1期,抑制细胞进入S期.结论从细胞分子水平说明通脉宁胶囊主要是通过影响细胞内DNA合成,减少有丝分裂,增加G0/G1期数目百分比,减少S期数目百分比而发挥抑制VSMC增殖作用.  相似文献   
66.
Observers of sports can reliably estimate who is leading or trailing based on nonverbal cues. Most likely, this is due to an adaptive mechanism of detecting motivationally relevant signals such as high status, superiority, and dominance. We reasoned that the relevance of leading athletes should lead to a sustained attentional prioritization. To test this idea, we recorded electroencephalography while 45 participants saw brief stills of athletes and estimated whether they were leading or trailing. Based on these recordings, we assessed event-related potentials and focused on the late positive complex (LPC), a well-established signature of controlled attention to motivationally relevant visual stimuli. Confirming our expectation, we found that LPC amplitude was significantly enhanced for leading as compared to trailing athletes. Moreover, this modulation was significantly related to behavioral performance on the score-estimation task. The present data suggest that subtle cues related to athletic supremacy are reliably differentiated in the human brain, involving a strong attentional orienting toward leading athletes. This mechanism might be part of an adaptive cognitive strategy that guides human social behavior.  相似文献   
67.
Affective startle modulation in the electromyographic (EMG), auditory startle evoked potentials, and visually evoked potentials (VEPs) were assessed while subjects evaluated pleasant, unpleasant, and neutral adjectives. Acoustic startle probes were presented at random time points 2.5-4.0 s after word onset. The visual P2 and P3 potentials were generally larger during processing of emotional than of neutral adjectives. In contrast, the late positive component was enhanced and was correlated with larger EMG startle responses and auditory startle evoked potential P3 amplitudes for pleasant words only. During internal cognitive activity, the startle reflex represents a measure of "processing interrupt." Thus the startle tone interrupted processing of particularly pleasant adjectives and caused re-alerting to environmental stimuli. Specific effects for pleasant material may arise from a "positivity offset," favoring responses to pleasant material at lower arousal levels.  相似文献   
68.
Gestures should play a role in second language comprehension, given their importance in conveying contextual information. In this study, the N400 and the LPC were evaluated in a task involving the observation of videos showing utterances accompanied by gestures. Students studying advanced (G-High participants) and basic German (G-Low participants) as a second language were investigated. The utterance–gesture congruence and metaphoric meaning of content were manipulated during the task. As in previous ERP reports with native speakers, metaphorical expressions were sensitive to gestures. In G-Low participants, no modulation in the 300–500 ms window was observed, and only a modest effect was observed for the 500–700 ms window. More subtle differences of verbal expression were not processed in this group. Consistent with previous reports of the same paradigm with native speakers, the N400 from G-High group discriminated both congruent and incongruent gestures as well as literal and metaphorical sentences. Our results suggest that semantic processing is robust in the learning of a second language, although the amplitude modulation and latency of ERPs might depend on the speaker's proficiency level.  相似文献   
69.
This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.  相似文献   
70.
This work describes a novel algorithm to identify laryngeal pathologies, by the digital analysis of the voice. It is based on Daubechies' discrete wavelet transform (DWT-db), linear prediction coefficients (LPC), and least squares support vector machines (LS-SVM). Wavelets with different support-sizes and three LS-SVM kernels are compared. Particularly, the proposed approach, implemented with modest computer requirements, leads to an adequate larynx pathology classifier to identify nodules in vocal folds. It presents over 90% of classification accuracy and has a low order of computational complexity in relation to the speech signal's length.  相似文献   
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