心脏Nmnat过表达联合耐力运动对果蝇高脂膳食诱发脂毒性心肌症的影响     

文登台  郑澜  陆凯  刘宪楚  后文其 《首都体育学院学报》2020,(1):87-96

利用UAS/hand-gal4系统构建果蝇心脏Nmnat基因特异性过表达,研究心脏Nmnat基因过表达联合耐力运动对高脂膳食诱发脂毒性心肌症的影响,并分析其分子机制。方法:雄性w^1118和NmnatUAS系果蝇分别与雌性hand-Gal4杂交,收集F1代心脏Nmnat正常表达(hand>w^1118)和过表达(hand>Nmnat)处女蝇,饲养至15 d后开始进行耐力运动(E)和高脂膳食(HFD),并分为hand>w^1118、hand>w^1118+E、hand>w^1118+HFD、hand>w^1118+HFD+E、hand>Nmnat、hand>Nmnat+E、hand>Nmnat+HFD、hand>Nmnat+HFD+E共8组,每组410只。ELISA检测心脏TAG、NAD+、SIR2蛋白去乙酰化、SOD活力和MDA水平,qRT-PCR检测心脏相关基因mRNA表达,M-mode检测心脏功能情况。结果:hand>w^1118+HFD+E果蝇心脏的Nmnat、dFoxo、bmm表达、NAD+水平、SIR2去乙酰化、SOD活力、缩短分数高于hand>w^1118+HFD(P<0.05或P<0.01),且d FAS和Col4al表达、TAG和MDA水平、心率和纤维性振颤低于hand>w^1118+HFD(P<0.05或P<0.01);hand>Nmnat果蝇心脏各指标与hand>Nmnat+HFD相比较未见显著差异(P>0.05);hand>Nmnat+HFD+E果蝇心脏的Nmnat、dFoxo、bmm表达、心脏NAD+水平、SIR2去乙酰化、SOD活力、心脏缩短分数高于hand>Nmnat+HFD(P<0.05或P<0.01),且dFAS和Col4al表达\TAG和MDA水平、心率和纤维性振颤低于hand>Nmnat+HFD(P<0.05或P<0.01)。结论:心脏Nmnat过表达和耐力运动均能抵抗果蝇高脂膳食诱发的心脏脂质过度堆积、氧化损伤、减弱心脏收缩能力和增加纤维性振颤,其分子机制与心脏Nmnat/NAD+/SIR2/dFoxo通路活性增强有关。心脏Nmnat基因过表达联合耐力运动能更好地降低脂毒性心肌症的发生概率,其机制与二者联合对心脏Nmnat/NAD+/SIR2/dFoxo通路活性上调的叠加作用有关。  相似文献   

双积分制下的新能源汽车产业链续航能力决策研究     

马亮  郭鹏辉 《科技管理研究》2019,(23)

在双积分制背景下，通过构建产业链自制式决策和外购式决策模型，研究了新能源汽车产业链中乘用车生产企业和电池生产企业的最优决策问题。结果表明：消费者支付意愿的提高、电池生产企业的研发能力的提升、市场上新能源汽车积分交易价格的上涨，都有利于两种决策产业链中新能源汽车续航能力的提高；自制式决策更有效，但外购式决策产业链可以通过提升消费者支付意愿、提高电池企业的研发能力来达到自制式决策产业链利润的效果。在外购式决策产业链中引入了政府补贴机制，实现产业链良性发展。在此基础上，给出了新能源汽车产业发展的建议。  相似文献   

心肌肌钙蛋白与马拉松等耐力运动后右心室心肌损伤的综述研究     

张玉丽  王松涛 《中国体育科技》2020,(6):22-31

作为心肌损伤的特异性指标,心肌肌钙蛋白(cTn)在临床诊断心肌病中具有较高的价值。马拉松等耐力运动后,血清cTn异常升高的生理、病理意义仍存在较大争议。通过总结马拉松等耐力运动后cTn的释放规律和右心室(RV)损伤情况,研究探讨了运动后血清cTn的可能来源,以及利用血清cTn评价运动后RV心肌损伤性质的可行性。研究认为:1)一次性马拉松等耐力运动后的血清cTn异常升高,可能是由于RV心肌结构蛋白损伤所致;2)一次性马拉松等耐力运动,可能导致不同性质的RV心肌损伤,通过结合运动后血清cTn的升高水平和持续升高的时间,可以对RV心肌损伤的性质进行评价。  相似文献   

Dietary nitrate supplementation does not improve cycling time-trial performance in the heat     

Georgina L. Kent  Brian Dawson  Gregory R. Cox  Louise M. Burke  Annette Eastwood  Kevin D. Croft 《Journal of sports sciences》2018,36(11):1204-1211

This investigation examined the effect of beetroot juice (BR) supplementation, a source of dietary nitrate (NO₃^?), on cycling time-trial (TT) performance and thermoregulation in the heat. In a double-blind, repeated-measures design, 12 male cyclists (age 26.6 ± 4.4 years, VO_2peak 65.8 ± 5.5 mL.kg^?1.min^?1) completed four cycling TTs (14 kJ.kg^?1) in hot (35°C, 48% relative humidity) and euthermic (21°C, 52%) conditions, following 3 days supplementation with BR (6.5 mmol NO₃^? for 2 days and 13 mmol NO₃^? on the final day), or NO₃^–depleted placebo (PLA). Salivary NO₃^? and nitrite, core (T_c) and mean skin temperature (T_sk) were measured. Salivary NO₃^? and nitrite increased significantly post-BR supplementation (p < 0.001). Average TT completion time (mm:ss) in hot conditions was 56:50 ± 05:08 with BR, compared with 58:30 ± 04:48 with PLA (p = 0.178). In euthermic conditions, average completion time was 53:09 ± 04:35 with BR, compared with 54:01 ± 04:05 with PLA (p = 0.380). The TT performance decreased (p < 0.001), and T_c (p < 0.001) and T_sk (p < 0.001) were higher in hot compared with euthermic conditions. In summary, BR supplementation has no significant effect on cycling TT performance in the heat.  相似文献   

Effects of resistance training on performance in previously trained endurance runners: A systematic review     

Manuel Alcaraz-Ibañez  Manuel Rodríguez-Pérez 《Journal of sports sciences》2018,36(6):613-629

The aim of this work was to identify, synthesize and evaluate the results of randomized controlled trials examining the effects of resistance training on performance indicators in previously trained endurance runners. A database search was carried out in PubMed, Science Direct, OvidSPMedLine, Wiley, Web of Science, ProQuest and Google Scholar. In accordance with the PRISMA checklist, 18 published articles dated prior to May 2016 involving 321 endurance runners were reviewed using the PEDro scale. Resistance training led to general improvements in muscular strength, running economy, muscle power factors, and direct performance in distances between 1,500 and 10,000 m. Such improvements were not accompanied by a significant increase in body mass or signs of overtraining. However, improvements did not occur in all cases, suggesting that they might depend on the specific characteristics of the resistance training applied. Although current evidence supports the effectiveness of resistance training to improve performance in already trained endurance runners, the methodological inconsistencies identified suggest that the results should be interpreted with caution. Future studies ought to investigate the benefits of resistance training in endurance runners while considering the existence of possible differentiated effects based on the specific characteristics of the resistance training carried out.  相似文献   

Cycling performance is superior for time-to-exhaustion versus time-trial in endurance laboratory tests     

Sarah L. Coakley 《Journal of sports sciences》2018,36(11):1228-1234

Time-to-exhaustion (TTE) trials are used in a laboratory setting to measure endurance performance. However, there is some concern with their ecological validity compared with time-trials (TT). Consequently, we aimed to compare cycling performance in TTE and TT where the duration of the trials was matched. Seventeen trained male cyclists completed three TTE trials at 80, 100 and 105% of maximal aerobic power (MAP). On a subsequent visit they performed three TT over the same duration as the TTE. Participants were blinded to elapsed time, power output, cadence and heart rate (HR). Average TTE was 865 ± 345 s, 165 ± 98 s and 117 ± 45 s for the 80, 100 and 105% trials respectively. Average power output was higher for TTE (294 ± 44 W) compared to TT (282 ± 43 W) at 80% MAP (P < 0.01), but not at 100 and 105% MAP (P > 0.05). There was no difference in cadence, HR, or RPE for any trial (P > 0.05). Critical power (CP) was also higher when derived from TTE compared to TT (P < 0.01). It is concluded that TTE results in a higher average power output compared to TT at 80% MAP. When determining CP, TTE rather than TT protocols appear superior.  相似文献   

蓝宝(螺旋藻)营养液的营养成分及保健功效研究     

许实波  许东晖  赵金华  王平学  杨冬梅 《中山大学学报论丛》1994,(6)

实验结果表明:蓝宝(螺旋藻)营养液含丰富蛋白质、β-胡萝卜素、叶绿素、多糖、维生素、人体必需氨基酸、微量元素及生理活性物质;能明显促进肠胃蠕动;降低胆固醇和血脂含量;提高机体恢复疲劳和耐高、低温应激能力;增强机体免疫功能,延缓衰老,提高记忆能力:对肝损伤具有保护作用等显著保健功效。  相似文献   

浅谈加入WTO对中国本土人力资源的影响     

刘其先  田锦川  刘砾 《新乡师范高等专科学校学报》2003,17(1):41-43

人才资源是中国经济发展的第一资源。加入WTO后,中国本土人力资源的流动具有三种可能的方式:在国内层面,大多数人才由落后地区向发达地区流动,少数人才向非发达地区逆向流动;在国际层面,很多优秀人才向外企、国外流动;国外部分优秀人才随着外资流进也一同流入中国国内,成为中国人才资源的增长点。针对人才外流现象,应建立有效开发机制;深化企业改革,激发人才事业心;强化企业文化和社会文化建设;构造一种限制人才外流的“文化壁垒”;深化用人制度改革,建立多渠道、多阶梯的升迁制度。  相似文献   

中长跑训练模式初探     

张补君 《宁波教育学院学报》2002,4(1):87-89

通过对中学中长跑运动员的耐力模式、力量模式、心理模式等的训练实践,并作了积极的尝试和实验,从中探索中学中长跑训练的最佳模式。  相似文献   

小教大专生语文课堂教学存在的问题和应对策略     

潘娟 《桂林师范高等专科学校学报》2006,20(3):73-76

分析小教大专生的小学语文课堂教学现状,指出其存在的几个主要问题,探讨提高他们小学语文教学能力的有效策略.  相似文献