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排序方式: 共有299条查询结果,搜索用时 0 毫秒
1.
目的对富硒钝顶螺旋藻的抗氧化、抗衰老、抗疲劳与增强免疫功能进行研究。方法通过对照服用富硒钝顶螺旋藻(每天每只小鼠摄入1.072μg Se)、普通钝顶螺旋藻小鼠和空白对照组小鼠血液中CAT(过氧化氢酶)、GSH-Px(谷胱甘肽过氧化物酶)和SOD(超氧化物歧化酶)活性的不同对富硒钝顶螺旋藻在抗氧化与抗衰老功能方面的强化作用进行评价。通过比较小鼠血液中的乳酸脱氢酶活性的变化以及游泳、爬杆能力的不同,并进行碳粒廓清和迟发型超敏反应实验,以此对富硒钝顶螺旋藻抗疲劳、增强免疫的效果进行研究。结果与普通钝顶螺旋藻相比,富硒钝顶螺旋藻具有更强的抗氧化、抗衰老、抗疲劳与增强免疫力的功能。 相似文献
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以川牛膝Cyathula officinalis种子为材料,通过高温高湿法进行人工加速老化,研究9个含水量对川牛膝种子活力的影响,并对不同含水量的抗老化机制进行了分析。研究结果表明,人工老化后,种子活力普遍有所降低;总体而言,含水量6.55%~4.78%的种子活力及抗老化能力相对较强,种子电导率值、POD活性、MDA含量升高幅度均较小,脱氢酶和SOD活性降低幅度亦较小;且在种子含水量5.77%时,未老化种子发芽试验各指标最高,人工老化和未老化的种子POD活性均最低,浸出液电导率较低,脱氢酶、SOD活性均最高,CAT活性亦较高。因此,在对川牛膝种子进行低温种质库保存时,为使其保持较高的活力和抗老化能力,应考虑将含水量降至接近(5.70±1)%。 相似文献
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目的 研究铁皮石斛复方制剂的抗氧化和延缓衰老作用.方法 通过二苯代苦味酰基自由基(DPPH)和羟自由基清除实验检测铁皮石斛复方制剂的体外抗氧化活性.利用秀丽线虫氧化应激模型,验证铁皮石斛复方制剂的体内抗氧化活性,同时在正常条件下检测铁皮石斛复方制剂对寿命的影响.在氧化应激条件下,测定铁皮石斛复方制剂对秀丽线虫活性氧(ROS)水平、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活力以及丙二醛(MDA)含量的影响.结果 铁皮石斛复方制剂对DPPH和羟自由基均有较好的清除作用,在16.0 mg/mL质量浓度下对DPPH和羟自由基清除率均达到60%.铁皮石斛复方制剂能提高秀丽线虫在高浓度百草枯(50 mmol/L)氧化胁迫条件下的存活率,同时也能延长其在正常条件下的寿命.在低浓度百草枯(2 mmol/L)氧化胁迫下,铁皮石斛复方制剂能显著降低秀丽线虫ROS含量并增强SOD活力,但对CAT活力和MDA含量没有明显影响.结论 铁皮石斛复方制剂具有抗氧化活性,能提高秀丽线虫在氧化胁迫条件下的存活率并延长寿命,其机制可能与提高秀丽线虫SOD活力有关. 相似文献
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Andrzej Bartke 《Clinical Interventions in Aging》2008,3(4):659-665
Although advanced age or symptoms of aging are not among approved indications for growth hormone (GH) therapy, recombinant human GH (rhGH) and various GH-related products are aggressively promoted as anti-aging therapies. Well-controlled studies of the effects of rhGH treatment in endocrinologically normal elderly subjects report some improvements in body composition and a number of undesirable side effects in sharp contrast to major benefits of GH therapy in patients with GH deficiency. Controversies surrounding the potential utility of GH in treatment of a geriatric patient are fueled by increasing evidence linking GH and cancer and by remarkably increased lifespan of GH-resistant and GH-deficient mice. Conservation of cellular signaling mechanisms that influence aging in organisms ranging from worms to mammals suggests that at least some of the results obtained in mutant mice are applicable to the human. We suggest that the normal, physiological functions of GH in promoting growth, sexual maturation and fecundity involve significant costs in terms of aging and life expectancy. Natural decline in GH levels during aging likely contributes to concomitant alterations in body composition and vigor but also may be offering important protection from cancer and other age-associated diseases. 相似文献
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Utilization of waste corn stalks (CS) has seized extensive attention due to high annual output and hazardous impact of piling aside or direct combustion on environment. However, previously there has been a lot of emphasis on improvement of its energy efficiency as solid fuel while limited investigations are available which explore the possibility of applying corn stalks as performance enhancer in asphalt binder. The purpose of this study is to examine the potential of employing hydrochar as modifiers in asphalt binder by a series of experimental tests. In this study, two hydrochar were produced from corn stalks by a novel process called hydrothermal carbonization at a different reaction temperature. The two hydrochar and their responding hydrochar-modified asphalt (HCMA) were tested by chemical and rheological tests. Chemical analysis detected the interaction between hydrochar and binder factions, resulting in poor compatibility but satisfying anti-aging property. Even though hydrochar increased the viscosity of bitumen, implying worse workability, and caused poor storage stability, ameliorated performance of asphalt binder at high temperature by incorporating hydrochar was verified by various criteria such as higher performance grade (PG) failure temperature and lower non-recoverable creep compliance (Jnr). Moreover, higher reaction temperature makes hydrochar’s particles smaller and more homogeneous, which results in slightly lower enhanced high temperature performance, more satisfying workability, better storage stability, and greater anti-aging effect of hydrochar-modified asphalt. Eventually, this study provided a promising win-win solution to environment problems concerning corn stalk treatment and shortage of asphalt binder. Further exploration of methods to improve HCMA’s storage stability, real-scale corroboration on trial section and life cycle assessment of asphalt pavement containing hydrochar modifiers will be followed in the future. 相似文献
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Peng Yu Weihong Li Han Li Shuang Ouyang Haiyang Cai Jing Wu Chaohui Tang Qingsong Huang 《Medicine》2020,99(49)
Background:Aging is a phenomenon that human''s physiology and psychology is progressive decline for natural environment. Health Qigong, as a convenient and effective exercise therapy,is widely used for anti-aging. However, there are no systematic reviews or meta-analysises to evaluate the efficacy and safety of Health Qigong on anti-aging.Methods:We will systematically search for 7 English databases(PubMed, Excerpta Medica Database, MEDLINE, Web of Science, Cochrane Library, SpringerLink, and WHO International Clinical Trials Registry Platform) and 4 Chinese databases(namely the China National Knowledge Infrastructure Database, the Wanfang Database, the Chinese Scientific Journal Database, and the Chinese BioMedical Literature Database) from their inceptions to August 2020. Randomized controlled trials (RCTs) using Health Qigong to anti-aging will be included. After the selection and extraction of eligible studies, a meta-analysis will be undertaken to assess the efficacy and safety of Health Qigong on anti-aging. Moreover, study selection, data extraction, and the evaluation of the methodological quality of trials will each be independently completed by at least 2 researchers. The Review Manager Software V.5.3 will be employed for meta-analysis to assess the risk of bias, data synthesis, and subgroup analysis.Results:This review will provide the latest knowledge and evidence on the efficacy and safety of Health Qigong for anti-aging through the analysis of various evaluation scales.Conclusion:The conclusion of this review will help clinicians provide effective exercise therapy for anti-aging.Registration number:INPLASY202090017 相似文献
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探讨膏摩"足三里"延缓衰老的机理。方法:对臭氧衰老模型小鼠"足三里"穴实施膏摩法治疗后,用彗星实验(Comet Assay)检测小鼠外周血淋巴细胞DNA的损伤程度。结果:膏摩小鼠外周血淋巴细胞DNA的拖尾率显著下降(P<0.05),尾长显著减短(P<0.05),差异有统计学意义。结论:膏摩法能够通过提高机体自身抗自由基氧化损伤的能力,减轻淋巴细胞DNA的损伤程度,从而达到延缓衰老的目的。 相似文献