Effects of periodic carbohydrate ingestion on endurance and cognitive performances during a 40-km cycling time-trial under normobaric hypoxia in well-trained triathletes     

Yi-Hung Liao  Toby Mündel  Yan-Ting Yang  Chen-Chan Wei  Shiow-Chwen Tsai 《Journal of sports sciences》2019,37(16):1805-1815

The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO₂max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO₂ = 20.9%), 2) hypoxic placebo (HPLA; FiO₂ = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO₂ = 16.3%). During the TT, physiological responses (SpO₂, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   

Comparison of Haptic and Biometric Properties,Bacterial Load,and Student Perception of Fixative Solutions: Formaldehyde Versus Chilean Conservative Fixative Solution with and without Formaldehyde in Pig Kidneys     

Marianne Skopnik-Chicago  Katherine Poblete-Cordero  Natali Zamora  Roberto Bastías  Pablo A. Lizana 《Anatomical sciences education》2021,14(6):836-846

One of the most widely used solutions to fix and preserve organic tissues is formaldehyde, despite reservations regarding its toxicity and the fact that formaldehyde-embalmed bodies lose their original characteristics. Anatomy laboratories have been replacing formaldehyde with solutions that retain the characteristics of fresh tissue. For this purpose, alternative solutions with a very low concentration of formaldehyde or without any formaldehyde have been analyzed. The objective of this study was to compare biometry, coloration, haptic properties, and bacterial load on animal specimens (pig kidneys) embalmed with formaldehyde, and with Chilean Conservative Fixative Solution with and without formaldehyde (formaldehyde chCFS and formaldehyde-free chCFS). Also, the perception of health and biological science students toward specimens treated with different solutions was assessed. The results indicated that there were no significant differences in specimens’ retraction, or bacterial load. Students showed a preference for organs embalmed in formaldehyde chCFS and formaldehyde-free chCFS; indicating that with these treatments they could better visualize structures and that the prosections had greater flexibility and the colors were more similar to those of fresh tissue. Additionally, students recommended the material embalmed in formaldehyde chCFS and formaldehyde-free chCFS for anatomy learning. In contrast, students indicated that formaldehyde-fixation negatively affected their practical experience. In conclusion, embalming with formaldehyde chCFS or formaldehyde-free chCFS provides an advantageous practical experience over the use of formaldehyde and may be an alternative to replace the use of formaldehyde in anatomy laboratories.  相似文献   

生物医学工程:一个发展迅速值得关注的交叉学科——生物力学、组织工程学、生物材料与人工器官   总被引：4，自引：0，他引：4  

李恩中  曹河圻  杜生明 《中国科学基金》2006,20(3):153-158

生物医学工程学（Biomedical Engineering，BME）是包含多种技术并相互交叉融合的一门科学。它综合了生物学、医学与工程学的理论和方法，研究生命体的构造、功能、状态和变化，研究新材料、新技术、新仪器设备，用于防病、治病、保护人民健康和提高医学水平。涉及科学领域广泛，除生物学、医学外，还有电子学、微电子学、现代计算机技术、化学、高分子化学、力学、近代物理学、光学、射线学、精密机械和近代高技术，并在不断发展扩大，是各国争相大力发展的高技术之一。本文主要从生物力学、组织工程学、生物材料与人工器官等方面进行探讨。  相似文献   

藏成药七十味珍珠丸中矿物质元素在体内蓄积性水平研究   总被引：1，自引：0，他引：1  

李天才  索有瑞 《中国科学院研究生院学报》2003,20(3):348-352

名贵藏成药七十味珍珠丸是传统藏药的典型代表,疗效显著.其中矿物类药的大量运用为现代医学科学不可理喻,给传统藏医药学的健康发展带来了困惑。以金诃七十味珍珠丸为研究材料,以Wistar大白鼠为试验对象,用等离子体发射光谱(ICP AES)和氢化物原子吸收光谱(HAAS)等分析仪器,测定了对照组和给药组实验动物在连续 1 8周试验期间心、肝、肾等组织器官中的矿物质元素含量水平,阐述金诃七十味珍珠丸中矿物质元素在动物主要组织器官中的长期蓄积性及其对生物机体的毒性效应  相似文献   

祁术的组织培养及快速繁殖技术研究     

胡长玉  叶玉娟  郝祥霞  胡跃 《黄山学院学报》2006,8(5):57-60

为研究祁术的组织培养及快速繁殖技术,选用祁术的叶片和下胚轴为外植体材料,接种于附加植物生长调节剂NAA,6-BA及其组合的MS固体培养基上.结果表明:下胚轴为外植体明显好于叶片,对于愈伤组织形成,叶片采用MS NAA(0.5mg/L) 6-BA(2mg/L);下胚轴MS NAA(0.5mg/L) 6-BA(2mg/L);MS NAA(0.5mg/L) 6-BA(1mg/L)为宜.对于叶片丛生芽愈伤组织培养基用MS NAA(0.2mg/L) 6-BA(2.8mg/L),下胚轴丛生芽愈伤组织培养基用MS NAA(0.01mg/L) 6-BA(0.1mg/L);MS NAA(0.05mg/L) 6-BA(0.1mg/L)为宜,诱导生根以1/2MS NAA0.3mg/L最佳,生根率达95%以上.  相似文献   

栽培因子对白肋烟叶片组织结构的调控     

柴家荣  刘敬业 《昆明师范高等专科学校学报》2006,28(4):17-22

研究表明：叶厚、栅厚、海厚、组织比、上表皮厚度等与烟叶品质和产量关系较密切的关键特征基本上都是TN86〉KY907〉TN90〉KY908〉K26〉KY8959，因而应以TN86，KY907，TN90的叶片组织结构较好．叶厚、栅厚、海厚、组织比、栅厚／叶厚及上下表皮厚度与栅栏组织细胞宽度等均随种植密度增加、封顶期后移和留叶数增多而呈下降趋势，但从低水平至中等水平的降幅很小，而从中水平至高水平的降幅较大；随施N量加大而呈上升趋势，低N至中N的升幅远大于中N至高N的升幅，施N量的作用大于种植密度，封顶期的效应远大于留叶数，且各项观测值均随叶位升高而增加．因而以18000株／hm^2，施N300kg／hm^2，全田50％现蕾后5d一次性封顶和留叶21～22片的试验组合的叶片组织结构较理想．叶片组织结构的关键特征均以完熟时最大、过熟时最小、初熟时在二者之间，下、中、上各叶位分别在封顶后第三、四、五周达完熟状态，兼顾各叶位宜在第4周砍收．  相似文献   

兔骨膜成骨细胞的分离培养   总被引：2，自引：0，他引：2  

张丽君  丁焕文 《深圳职业技术学院学报》2004,3(2):34-37

采用植块法和分批消化法相结合的方法分离得到了兔骨膜成骨细胞,鉴定后进一步研究了其生长特性。结果表明:该法可以在短时间内得到足够数量的细胞且纯度较高(8d达1.8 × 105个／ml),其最终碱性磷酸酶(ALP)分泌量为(13.12±0.18)IU／ml,骨钙素(BGP)量约为(20±0.3)ng／ml。  相似文献   

优质葡萄品种组培快繁育苗工厂化技术研究   总被引：1，自引：0，他引：1  

何家涛 《襄樊职业技术学院学报》2002,1(1):16-19

本实验研究了探讨了葡萄组培中的外植体诱导建立无菌繁殖系；外植体生长分化和增殖培养基的筛选；壮苗生根及驯化移栽等关键技术环节，从而使优质葡萄品种组培快繁工厂化大规模育苗成为可能。  相似文献   

"幸香"草莓组培快繁技术研究   总被引：2，自引：0，他引：2  

张铁  阙娥 《保山师专学报》2005,24(5):61-62

以幸香草莓为试材,对草莓葡匐茎茎尖生长点进行组织培养,筛选出适宜幸香草莓诱导分化培养基为MS BA0.50mg/L NAA0.10mg/L、继代增殖培养基为MS IBA0.10 mg/L BA0.50 mg/L、生根培养基为1/2MS IBA0.04 mg/L 糖15g/L.  相似文献   

MEASUREMENT OF THE DIELECTRIC PROPERTIES OF BIOLOGICAL TISSUE     

顾本立  黄雷 《东南大学学报》1989,(1)

An open-ended coaxial line reflection method especially suitable for meas-uring the dielectric properties of biological tissue in vivo is described.This method offersthe advantage of not requiring any special preparation of the samples to be measured but aclose contact with the open end of a coaxial line.It is,therefore,very convenient to acquirea large number of measurement data in broad band rapidly.The method may also be usedto measure the properties of other substances.The measuring system consists of a networkanalyzer controlled by a microcomputer and calibrated by using ANA procedure to elimi-hate the influnce of error network introduced by the adapter,some connectors,etc.In or-der to reach higher accuracy,the iterative method is used to determine the parameters ofthe equivalent circuit.Measurements of permeativities of some living tissues have been per-formed in the frequency band of 0.5-2GHz.Compared with the results known in somepapers,the validity of this method has been confirmed.The difference in dielectric proper-ties between living and dead tissues,and the tissue permeativites(ε)versus frequency andduration of measurement after death have also been measured.  相似文献