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991.
Two new quassinoids, brujavanol A (1) and brujavanol B (2), along with five known quassinoids (3–7), were isolated from the roots of Brucea javanica. Their structures were elucidated by spectroscopic methods. The antimalarial and cytotoxic activities of the isolated compounds were also assessed. Compounds 1 and 2 exhibited significant in vitro cytotoxicity against human oral cavity cancer (KB) cells with IC50 values of 1.30 and 2.36 μg/ml, respectively, whereas compound 3 showed excellent antiplasmodial activity against the Plasmodium falciparum strains, K1 (IC50 = 0.58 μg/ml). 相似文献
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994.
目的探讨复方中药含药血清对人A375黑素瘤细胞酪氨酸酶(TYR)活性的影响。方法体外培养人A375黑素瘤细胞,采用多巴速率氧化法研究复方中药含药血清对TYR活性的影响。结果低浓度(5%~10%)的Ⅰ方、Ⅱ方、Ⅲ方对酪氨酸酶活性无明显激活作用(P〉0.05);高浓度(20%~30%)的Ⅰ方、Ⅲ方、Ⅵ方对TYR活性均有明显激活作用(P〈0.05),以Ⅵ方作用最显著,且与其它各组相比,差异均有统计学意义(P〈0.01)。结论对TYR具有激活作用的中药组成复方并不一定对TYR有激活作用,具有祛风活血和补肾三重作用的Ⅵ方在促进TYR活性上优于祛风除湿Ⅰ方、养血活血Ⅱ方和滋补肝肾Ⅲ方。 相似文献
995.
As the benefits that regular physical activity (PA) have on obesity are well known, many interventions promote active lifestyle adoption among obese populations. This meta‐analysis aims to determine (i) the global effect that interventions promoting PA among obese populations have on their PA behaviour; (ii) variations in the effect of interventions depending on the PA indicator used; (iii) the programme's dose characteristics and (iv) maintenance of the intervention effects after the intervention has ended. A comprehensive search through databases and review articles was completed. Forty‐six studies met the inclusion criteria. Calculations of effect size (Cohen's d) and a moderator analysis were conducted. The meta‐analysis showed that interventions globally have an impact on the PA behaviour of obese populations (d = 0.44; 95% CI = 0.31, 0.57). The moderator analysis revealed that interventions of less than 6 months reported significantly larger effects than longer interventions. Moreover, the interventions had a stronger impact on the number of steps and the PA indexes (i.e. composite scores reflecting PA practice) than on other PA indicators. Finally, the analysis revealed that interventions succeed in maintaining PA behaviour after the intervention is over. However, relatively few studies addressed this issue (n = 9). Despite global positive effects, further research is needed to determine the optimal dose for interventions and to evaluate the maintenance of intervention effects. 相似文献
996.
Two parallel literatures on the physical activity (PA) identity and schema constructs have the potential to supplement traditional social cognitive approaches used for PA promotion. The purpose of this paper was to review schema/identity research and appraise its relationship with PA via meta-analysis followed by thematic analyses of its correlates, as well as its proposed mechanisms on PA. Eligible studies were from English, peer-reviewed published articles that examined identity and/or schema in the context of PA. Searches were completed in June 2015 in five databases. Sixty-two independent data-sets (32 available for meta-analysis), primarily of modest quality, were identified. Results of the random effects meta-analysis showed that the point-estimate between identity/schema and behaviour was r?=?.44 (CI?=?.39?.48), and invariant to selected study characteristics. Thematic review showed that identity/schema was associated with commitment, ability, affective judgments, identified/integrated regulation and social comparison and predicted intention, self-regulatory efficacy, and self-regulation strategy use. It had reliable evidence as a moderator of the intention–behavior relationship, was associated with increases in the speed of processing of relevant information and created negative affect under hypothetical identity–behavior discrepant situations. While this initial research is promising, more rigorous research designs, including interventions to increase identity/schema, are warranted. 相似文献
997.
998.
《The Journal for Nurse Practitioners》2017,13(1):34-40
Consumer-based wearable fitness trackers present a new array of opportunities and challenges to nurse practitioners engaged in health promotion research. Key advantages include the ability to provide continuous, objective, remote monitoring of physical activity and the potential to improve the efficacy of physical activity interventions. This article provides an overview of fitness trackers, including their functions and accuracy, and addresses the following key issues to consider before using trackers in research: 1) when to use a fitness tracker, 2) choosing a brand and model, 3) encouraging good compliance, and 4) extracting and using the data. 相似文献
999.
1000.
《Asian Pacific Journal of Tropical Biomedicine》2014,4(12):964-970
ObjectiveTo perform phytochemical screening, estimate total phenolics, flavonoids and to evaluate antioxidant potential of Moringa peregrina (M. peregrina) leaves.MethodsThe dried powdered leaves of M. peregrina (150 g) were extracted exhaustively by Soxhlet with ethanol and then fractionated into hexane, chloroform, ethy alacetate and methanol. All the prepared extracts were also analyzed by gas chromatography-mass spectrometry to identify and characterize the chemical compounds present in the crude extracts. Folin- Ciocalteu reagent and aluminium chloride colorimetric methods were used to estimate total phenolic and flavonoid content of extracts. Hydrogen peroxide and 1,1 diphenyl -2-picrylhydrazyl were used to determine in vitro antioxidant activity.ResultsPhytochemical analysis of ethanol extract showed presence of major classes of phytochemicals. Gas chromatography-mass spectrometry results revealed presence of 19 phytoconstituents in hexane extract, 6 in ethyl acetate and 7 compounds in methanolic extract. Methanol extract was found to contain the highest phenolic content and flavonoids. In vitro antioxidant activities of all crude extracts were significant and comparable with the standard ascorbic acid.ConclusionsResults of this study show that the leaves of M. peregrina are the rich source of phenolic compounds that can play an important role in preventing the progression of many diseases. 相似文献