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61.
Neurofeedback training (NFT) has shown promising results in recent years as a tool to address the effects of age-related cognitive decline in the elderly. Since previous studies have linked reduced complexity of electroencephalography (EEG) signal to the process of cognitive decline, we propose the use of non-linear methods to characterise changes in EEG complexity induced by NFT. In this study, we analyse the pre- and post-training EEG from 11 elderly subjects who performed an NFT based on motor imagery (MI–NFT). Spectral changes were studied using relative power (RP) from classical frequency bands (delta, theta, alpha, and beta), whilst multiscale entropy (MSE) was applied to assess EEG-induced complexity changes. Furthermore, we analysed the subject’s scores from Luria tests performed before and after MI–NFT. We found that MI–NFT induced a power shift towards rapid frequencies, as well as an increase of EEG complexity in all channels, except for C3. These improvements were most evident in frontal channels. Moreover, results from cognitive tests showed significant enhancement in intellectual and memory functions. Therefore, our findings suggest the usefulness of MI–NFT to improve cognitive functions in the elderly and encourage future studies to use MSE as a metric to characterise EEG changes induced by MI–NFT.  相似文献   
62.
Along with the increased knowledge about the positive health effects of food bioactives, the eating habits of many individuals have changed to obtain higher nutritional benefits from foods. Fruits are among the most preferred food materials in this regard. In particular, berry fruits are important sources in the diet in terms of their high nutritional content including vitamins, minerals, and phenolic compounds. Berry fruits have remedial effects on several diseases and these health-promoting impacts are associated with their phenolic compounds which may vary depending on the type and variety of the fruit coupled with other factors including climate, agricultural conditions, etc. Most of the berries have outstanding beneficial roles in many body systems of humans such as gastrointestinal, cardiovascular, immune, and nervous systems. Furthermore, they are effective on some metabolic disorders and several types of cancer. In this review, the health-promoting effects of bioactive compounds in berry fruits are presented and the most recent in vivo, in vitro, and clinical studies are discussed from a food science and nutrition point of view.  相似文献   
63.
基于现代信息技术与教学手段,在土木工程、机械车辆和航空航天等专业的课程教学中,开展了课程育人的探索与实践,将课程思政与教书育人融于专业基础课程的教学过程,以实现育人与育才的统一,为中华民族的伟大复兴培育德才兼备的优秀人才。  相似文献   
64.
A rapid, sensitive and specific method for quantifying clonazepam in human plasma using diazepam as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using a hexane/diethylether (20 : 80, v/v) solution. The extracts were analysed by high-performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-MS-MS). Chromatography was performed on a Jones Genesis C8 4 microm analytical column (100 x 2.1 mm i.d.). The method had a chromatographic run time of 3.0 min and a linear calibration curve over the range 0.5-50 ng/ml (r2 > 0.9965). The limit of quantification was 0.5 ng/ml. This HPLC/MS/MS procedure was used to assess the bioequivalence of two clonazepam 2 mg tablet formulations (clonazepam test formulation from Ranbaxy Laboratories Ltd and Rivotril from Roche Laboratórios Ltda as standard reference formulation).  相似文献   
65.
People are always susceptible to a loss of stability in urban floodwaters that leads to serious casualties. Thus, the safety criterion for the instability of people in floodwaters must be determined. In this study, the hydrodynamic criterion of the instability of people in floodwaters in terms of the incipient velocity and water depth is derived using the probability method based on Shannon entropy theory. The derived model can characterize variations in the incipient velocity of people in floodwaters with respect to the inundating water depth. Furthermore, a comparison with seven experimental datasets available in the literature shows the validity of the proposed entropy-based model considering data scattering. A sensitivity analysis of the derived model to some of the incorporated parameters was performed, and the qualitative results are in accordance with our understanding of the physical mechanism of the instability of people in floodwaters. Taking the physical parameters (height and mass) of Chinese adults and children as a representative example, this study also showed the vulnerability degree of Chinese adults and children subject to floodwaters. These findings could provide a reference for administrators and stakeholders for flood hazard mitigation and flood strategy management. This study shows that an entropy-based method could be a valuable addition to existing deterministic models for characterizing the instability criterion of people in an urban flooding event.  相似文献   
66.
微量元素对老年人健康的作用与危害   总被引:2,自引:1,他引:2  
介绍了微量元素的生理功能,微量元素与衰老,长寿和老年人冠心病,高血压,脑血管疾病,肿瘤,糖尿病等五种常见病的关系。还特别介绍了锌对人类健康的作用和铅对人类健康的危害。老年人体内有益的微量元素,如铁,锌,锰,铬,硒等比较缺乏,相反镍,铅,铝等有害的微量元素比较高。长寿老人头发中有益微量元素锰,钴,硒,铜,锌,铬等均有较高水平。人要长寿,必须维持体内微量元素的水平,微量元素过低或者过高应及时通过食疗或药物治疗进行调节。  相似文献   
67.
探讨新疆柯尔克孜族和维吾尔族人群血管紧张素转化酶(ACE)基因rs1799752位点插入或缺失(I/D)多态性及其与2型糖尿病(TypeⅡdiabetes mellitus,T2DM)的关系.方法采用病例-对照的研究设计.采集无血缘关系、年龄性别匹配的新疆柯尔克孜族样本117例、维吾尔族样本127例,分为2型糖尿病组(T2DM)、糖耐量异常组(impaired glucose tolerance, IGT)和糖耐量正常组(normal glucose tolerance, NGT),以Hardy-Weinberg平衡检验确认研究样本的群体代表性,采用PCR技术检测ACE基因I/D多态性.结果(1)病例组与对照组ACE基因多态性的分布符合Hardy-Weinberg平衡定律,所选人群具有代表性;(2)柯尔克孜族DD型42.74%,ID型31.58%,II型26.50%,D和I 等位基因频率分别为58.115%和41.876%;维吾尔族DD型35.43%,ID型28.35%,II型36.22%,D和I 等位基因频率分别为49.626%和50.387%.(3)ACE基因频率差异在柯尔克孜族(χ2=70.11,P 〈0.01),维吾尔族(χ^2=35.11,P〈0.01)的糖调节异常组与糖耐量正常组间,分别具有统计学意义.在维吾尔族T2DM组中携带DD、ID、ID+DD基因型的个体较携带II基因型的个体发生糖代谢异常(T2DM+IGT)的危险性增加(OR=7.812,95%CI=3.135-19.607;OR=4.854,95%CI=1.835-12.821;OR=6.410,95%CI=2.865-14.286,携带D等位基因的个体较携带I等位基因的个体发生糖代谢异常(T2DM+IGT)的危险性增加(OR=4.444,95%CI=2.617-7.576),而柯尔克孜族DD、ID+DD基因型和D等位基因性对糖代谢异常(T2DM+IGT)的发病风险降低.结论ACE基因I/D多态性与新疆两个少数民族T2DM相关,ACE基因I/D多态性可能是维吾尔族T2DM的危险因素,柯尔克孜族的保护因素.  相似文献   
68.
69.
大蒜与保健   总被引:3,自引:0,他引:3  
邵国强 《化学教育》2004,25(10):3-6
大蒜是人类的保健食品。本文介绍了大蒜的化学组成、生理功能和除臭方法及其产品开发。旨在了解大蒜、预防疾病和促进健康。  相似文献   
70.
Iberian ham is one of the most representative Spanish products and presents an excellent nutritional and sensory quality. Iberian ham trimming fat is considered a by-product and to give a new use to this remaining part could represent a healthy and innovative option for obtaining sustainable foods. The purpose of this work was to obtain a new bioactive ingredient from Iberian ham trimming fat with the highest amount of antioxidants and monounsaturated fatty acids (MUFA), using a new non-invasive solvent-free method. To obtain the essence, two different extraction procedures were carried out. After fatty acid characterization, degree of acidity, peroxide index and a basic sensory analysis were performed. Antioxidant in vitro activity and total phenolic compounds (TPC) were also determined. This new ingredient showed a better sensory profile than raw ham fat, a lower degree of acidity, a higher content of MUFAs, and also showed a higher antioxidant capacity and an increase in phenolic compounds compared to the raw material. This bioactive essence could be used as a food, a cosmetic or a nutraceutical ingredient to prevent certain diseases related to oxidative stress and could also contribute to the maintenance of the circular economy.  相似文献   
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