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间歇性低氧对训练大鼠血清NO、NOS及自由基代谢的影响 总被引：5，自引：0，他引：5
低氧帐篷系统模拟海拔3000m的低氧环境，建立以SD大鼠为研究对象的动物模型，采用高住低练方法，观察间歇性低氧对训练大鼠血清NO、NOS、MDA、SOD的影响．结果表明，间歇性低氧结合运动训练能明显提高大鼠血清NO、NOS、SOD，显著性抑制MDA的水平、 相似文献
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一氧化氮(NO)参与肝细胞的多项生理功能调节,参与病毒性肝炎的病理过程。一氧化氮合酶(NOS)为产生NO的限速酶,与NO的各种生理功能密切相关。本文综述了NOS基因在正常肝组织和病毒性肝炎的不同表达情况及其作用和意义。 相似文献
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目的探讨不同强度运动训练对大鼠睾丸组织NOS和细胞凋亡表达的影响及其与睾酮水平相关性。方法24只健康雄性大鼠,随机分为对照组,有氧运动组,大强度运动组,每组8只。采用递增强度方式进行跑台运动,训练过程共持续8周。测定大鼠睾丸组织NOS表达、细胞凋亡及血睾酮的含量。结果与安静对照组相比,有氧训练组大鼠睾丸组织NOS表达、细胞凋亡及血睾酮含量无显著性差异。而疲劳训练组大鼠睾丸组织eNOS和Bax表达显著升高(P<0.05),nNOSi、NOS和Bcl-2表达及血睾酮含量显著降低(P<0.05)。结论有氧训练大鼠睾丸组织NOS表达、细胞凋亡对血睾酮水平影响不显著;大强度疲劳训练大鼠睾丸组织NO过量表达,细胞凋亡明显增加,血睾酮含量显著降低。推测,大强度运动训练使大鼠睾丸组织NO过量表达,诱导睾丸组织细胞凋亡明显增多,从而抑制睾酮的分泌。 相似文献
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老龄大鼠脑组织SOD/MDA与NO/NOS的相关性研究 总被引：1，自引：0，他引：1
目的:探讨衰老进程中老龄大鼠脑组织超氧化物歧化酶(SOD)/丙二醛(MDA),一氧化氮(N0)/一氧化氮合酶(NOS)的变化,长期游泳运动对SOD/MDA、NO/NOS的影响以及SOD/MDA与NO/NOS之间的相互关系.方法:青龄与老龄雄性SD大鼠24只,分为青龄对照组(QC)8只,老龄对照组(LC)8只,老龄运动组(LT)8只.LT组坚持游泳锻炼8周,其余二组自由生活.实验结束后取样测定脑组织MDA与NOS含量以及SOD与NOS活性,并采用直线相关法对脑组织SOD/MDA与NO/NOS进行相关性分析.结果:与青龄对照组相比,老龄对照组脑组织SOD活性下降了21.18%(P<0.01),MDA含量升高了49.68%(P<0.01),NO含量下降了38.25%(P<0.01),NOS活性下降了34.81%(P<0.01);与老龄对照组相比,老龄运动组脑组织SOD活性提高了16.95%(P>O.05),MDA含量下降了28.27%(PNOS活性提高了46.61%(PNOS不存在直线相关关系.结论:随衰老进程,SOD、MDA、NO、NOS发生了极为显著的变化,SOD/MDA与NO/NOS之间存在着相关关系,长期游泳运动可在一定程度上逆转上述指标随增龄出现的变化,是延缓衰老的重要手段. 相似文献
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This study tracked the influence of explicit reflective instructional methods on cultural values, ethical and intellectual development, and the relationship of these with preservice teachers' views of nature of science (NOS). The researchers used the Views of Nature of Science Form B (VNOS B) to describe NOS views, the Learning Context Questionnaire (LCQ) to classify preservice teachers' ethical and intellectual positions using Perry's scheme, and the Schwartz Values Inventory (SVI) to measure preservice teachers' cultural values. The interventions took place in two concurrent courses: a science methods course, and a foundations of early childhood course. The science methods course explicitly emphasized NOS throughout the semester, and the foundations of early childhood course reinforced these ideas through cultural activities that stressed empirical evidence. Analysis of data showed relationships between preservice teachers' Perry positions and responses on the VNOS B with those at higher positions exhibiting more informed NOS views. Relationships between preservice teachers' NOS views and their cultural values were identified, such as those at the dualism position holding achievement more highly for scientists than those at other Perry positions. The values preservice teachers held personally were different from those they held as important for scientists. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 45: 748–770, 2008 相似文献
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Learning science through research apprenticeships: A critical review of the literature 总被引：1，自引：0，他引：1
Science education models for secondary and college students as well as K‐12 teachers have been dominated by classroom‐based approaches. Recently, research apprenticeships wherein learners worked with practicing scientists on authentic scientific research have become increasingly popular. The purpose of this critical review of the literature was to review and synthesize empirical studies that have explored learning outcomes associated with research apprenticeships for science learners. We reviewed 53 studies of scientific research apprenticeship experiences for secondary students, undergraduates and teachers, both pre‐service and in‐service. The review explored various learning outcomes associated with participation in research apprenticeships. These outcomes included effects of apprenticeship experiences on participant career aspirations, ideas about the nature of science (NOS), understandings of scientific content, confidence for doing science and intellectual development. The extant literature supported many of the presumed positive associations between apprenticeship experiences and desired learning outcomes, but findings related to some themes (e.g., NOS understandings) supported conflicting conclusions. Implications included importance of the length of the apprenticeship, need to explicitly place attention on desired outcomes, and engagement of participants. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 47:235–256, 2010 相似文献
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运动训练对大鼠主动脉一氧化氮合酶及细胞凋亡的影响 总被引：2，自引：4，他引：2
目的:探讨不同强度训练对大鼠主动脉一氧化氮合酶(NOS)及细胞凋亡的影响。方法:采用跑台训练方式,建立大鼠有氧运动和疲劳运动模型,运用免疫组织化学SABC法研究不同运动强度对大鼠主动脉神经型一氧化氮合酶(neuronal nitric oxide synthase,nNOS)、诱导型一氧化氮合酶(in-duced nitric oxide synthase,iNOS)、内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)和细胞凋亡蛋白(Bcl-2/Bax)表达的影响。结果:有氧训练组与对照组比较,主动脉NOS 3个亚型及Bcl-2,Bax表达差异显著(P<0.05);疲劳训练组与对照组和有氧训练组比较,主动脉iNOS、eNOS及Bcl-2,Bax表达差异显著(P<0.05),nNOS虽有增加但差异不显著。结论:运动可引起大鼠主动脉NOS 3个亚型及Bcl-2,Bax表达变化,且与运动强度关系密切。有氧训练可使主动脉NOS适度表达且抑制细胞凋亡,疲劳训练会导致大鼠主动脉iNOS过量表达,细胞发生凋亡现象。因此认为,运动训练引起NOS亚型表达变化与运动诱导的主动脉细胞凋亡关系密切。 相似文献
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This study assessed the influence of a 3‐year professional development program on elementary teachers' views of nature of science (NOS), instructional practice to promote students' appropriate NOS views, and the influence of participants' instruction on elementary student NOS views. Using the VNOS‐B and associated interviews the researchers tracked the changes in NOS views of teacher participants throughout the professional development program. The teachers participated in explicit–reflective activities, embedded in a program that emphasized scientific inquiry and inquiry‐based instruction, to help them improve their own elementary students' views of NOS. Elementary students were interviewed using the VNOS‐D to track changes in their NOS views, using classroom observations to note teacher influences on student ideas. Analysis of the VNOS‐B and VNOS‐D showed that teachers and most grades of elementary students showed positive changes in their views of NOS. The teachers also improved in their science pedagogy, as evidenced by analysis of their teaching. Implications for teacher professional development programs are made. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 44: 653–680, 2007 相似文献
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通过观察经中等强度有氧运动后大鼠对损害性应激的反应变化及神经内分泌改变,探讨中等强度有氧运动对大鼠应对外界损害性应激能力的影响及其机制。 相似文献