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排序方式: 共有299条查询结果,搜索用时 15 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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中药多糖抗衰老作用机制研究进展 总被引:1,自引:0,他引:1
近年来,人口老龄化趋势不断加剧,养老负担及高发率的老年病对社会、经济的发展产生了一定的负面影响.衰老是一个涉及多器官、多因素与多种疾病发生有关的生物学过程,由于衰老的发生发展涉及多种信号通路,如营养感应信号通路、胞内应激信号通路等,成为抗衰老药物研究的热点与难点.中药活性成分-多糖类物质,具有抗肿瘤、降血糖、降血脂、抗... 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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Tnia Almeida Patrícia Moreira Fbio J. Sousa Cludia Pereira Armando J. D. Silvestre Carla Vilela Carmen S. R. Freire 《Materials》2022,15(5)
Bacterial nanocellulose (BNC) membranes, with remarkable physical and mechanical properties, emerged as a versatile biopolymeric carrier of bioactive compounds for skin care applications. In this study, BNC membranes were loaded with glycerol (as plasticizer and humectant agent) and different doses (1–3 μg cm−2) of an aqueous extract obtained from the hydro-distillation of Eucalyptus globulus Labill. leaves (HDE), for application as sheet facial masks. All membranes are resistant and highly malleable at dry and wet states, with similar or even better mechanical properties than those of a commercial BNC mask. Moreover, the HDE was found to confer a dose-dependent antioxidant activity to pure BNC. Additionally, upon 3 months of storage at 22–25 °C and 52% relative humidity (RH) or at 40 °C and 75% RH, it was confirmed that the antioxidant activity and the macroscopic aspect of the membrane with 2 μg cm−2 of HDE were maintained. Membranes were also shown to be non-cytotoxic towards HaCaT and NIH/3T3 cells, and the membrane with 2 μg cm−2 of HDE caused a significant reduction in the senescence-associated β-galactosidase activity in NIH/3T3 cells. These findings suggest the suitability and potential of the obtained membranes as bioactive facial masks for anti-aging applications. 相似文献
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目的 研究棉子糖抗衰老活性并探讨其作用机制。方法 棉子糖(150、200、250μmol·L-1)加到大肠杆菌中孵育秀丽隐杆线虫后,显微镜下观察线虫身体弯曲频率、头尾摆动频率、体长,观察热应激刺激下线虫的存活时间;通过脂褐素荧光强度检测评价棉子糖对线虫抗衰老能力的影响;采用DAF-16核定位测定和超氧化物歧化酶-3(SOD-3)表达测定研究其抗衰老的相关机制。结果 与对照组比较,棉子糖3个浓度均使线虫的身体弯曲频率加快(P<0.001);200μmol·L-1棉子糖使线虫头尾摆动频率加快(P<0.01);体长测试结果显示棉子糖3个浓度均对线虫生长发育无毒害作用。热应激测试中,与对照组比较,棉子糖3个浓度均显著延长线虫在热应激条件下的存活时间(P<0.05)。脂褐素测试中,与对照组比较,棉子糖3个浓度均使线虫体内脂褐素含量显著降低(P<0.01)。DAF-16核定位测定中,棉子糖3个浓度均促进DAF-16蛋白入核表达。SOD-3表达测定中,与对照组比较,棉子糖250μmol·L-1浓度组的SOD-3蛋白表达水平显著上升(P<0.05),与DAF-16核定位测定一并说明棉子糖抗衰老活性依赖ⅡS分子信号通路。结论 棉子糖能够促进线虫的活动能力,对其生长发育无毒害性,并能延缓线虫的衰老速度,促进DAF-16蛋白入核表达,提高SOD-3蛋白表达水平,其抗衰老机制依赖ⅡS分子信号通路。 相似文献