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1.
对人体生理特性的研究结果显示,部分运动相关基因如α-肌动蛋白-3、血管紧张素I转换酶、Ⅱ型活化素受体B的基因多态性会明显影响运动员的运动天赋和体能。建立优秀运动员基因库,发现和鉴定可影响运动能力的基因变异体,使得在儿童中开展DNA测试,挑选适合某种特殊体育项目的运动天才和优化训练方法具有一定现实操作意义。另一方面,随着滥用基因技术以提高运动能力的可能性不断提高,部分基因有可能作为基因兴奋剂,通过基因转移的方法导入人体,其所涉及的伦理问题、对人类健康及社会的潜在危害等,已经引起了来自自然科学和社会科学不同领域的广泛关注。  相似文献   

2.
目前所称的兴奋剂实为禁用物质和禁用方法的统称。根据国际奥委会医学委员会1996年最新公布的禁用物质和禁用方法,介绍了兴奋剂的使用、危害和控制等问题。指出兴奋剂的使用违反了运动和医学的道德标准,也损害了运动员身体健康,必须坚决反对。  相似文献   

3.
竞技体育中的兴奋剂使用和控制(二)方子龙,杨则宜(国家体委运动医学研究所100029)(续1996年第9期第14页)2禁用方法2.1血液兴奋剂血液兴奋剂是指向运动员输入血液、红细胞和相关的血制品。血液的来源可以是运动员本人(血液回输)或其他人(异体输...  相似文献   

4.
“兴奋剂”对我们来说不是一个陌生的词汇,我们在许多体育赛事报道中总能听到。但是,“兴奋剂”并非只存在于体育运动中,它和我们的生活也有密切的联系。如今,兴奋剂滥用问题早已经超越了体育运动的范畴,日益走进我们的生活。  相似文献   

5.
2007年10月19日,服务科学、世界领先的赛默飞世尔科技与中国兴奋剂检测中心在北京签署了2008年奥运会兴奋剂检测项目合作计划书。协议确定了赛默飞世尔参与和支持2008年奥运会兴奋剂检测的仪器和技术服务.以保证奥运会期间兴奋剂检测任务的完成。  相似文献   

6.
《中国生物工程杂志》2007,27(10):125-125
从兴奋剂检测、空气质量监测到绿色奥运的食品安全,全球领先的科学仪器供应商赛默飞世尔科技一直在为2008北京奥运的举办贡献着自己的力量。随着奥运会的临近,赛默飞世尔的领先技术将渗透到与奥运息息相关的众多领域。为兴奋剂鉴定提供技术平台2008北京奥运会兴奋剂检测仪器的公开国际招标中,赛默飞世尔从众多竞争对手中脱颖而出,为国家兴奋剂检测中心提供一台DFS高分辨率质谱仪。该仪器可以同时实现药物检测的快速筛选和确认分析,将承担2008北京奥运会兴奋剂确认检测的任务。DFS高分辨率质谱仪与众不同,其灵敏度一直居于行业领先,超过同…  相似文献   

7.
兴奋剂的生理作用及其危害   总被引:1,自引:0,他引:1  
李慧 《生物学杂志》1995,12(4):46-47
兴奋剂的生理作用及其危害李慧河南省新乡平原大学生生物系,453003当今世界性的体育比赛竞争越来越激烈,其成绩正向着生理极限逼近,滥用兴奋剂的运动员越来越多,手段也千变万化。据奥委会官员和专家们分析,在世界著名运动员中,有50%的人靠服用非法药物来提...  相似文献   

8.
苯丙胺类兴奋剂滥用可致强烈精神依赖,引起精神分裂症以及认知功能损害.研究认为中枢神经胆碱能系统参与药物依赖的调控,苯丙胺类兴奋剂依赖后导致了部分脑区乙酰胆碱释放水平、囊泡转运蛋白、胆碱能受体表达以及受体功能发生了适应性的改变,并与依赖行为的表达存在一定的关系;部分胆碱能受体抑制剂可干预依赖行为的表达.目前尚未有研究证实苯丙胺类兴奋剂对胆碱能神经元有直接损害作用.本文对苯丙胺类药物依赖与中枢胆碱能系统关系的研究进展作一综述.  相似文献   

9.
2007年10月19日世界领先的赛默飞世尔科技(原热电公司)与中国兴奋剂检测中心在北京签署2008年奥运会兴奋剂检测项目合作计划书。协议确定了赛默飞世尔参与和支持2008年奥运会兴奋剂检测的仪器和技术服务,以保证奥运会期间兴奋剂的检测任务的完成。  相似文献   

10.
2007年10月19日,服务科学、世界领先的赛默飞世尔科技与中国兴奋剂检测中心在北京签署了2008年奥运会兴奋剂检测项目合作计划书。协议确定了赛默飞世尔参与和支持2008年奥运会兴奋剂检测的仪器和技术服务.以保证奥运会期间兴奋剂检测任务的完成。  相似文献   

11.
In the past few years considerable progress regarding the knowledge of the human genome map has been achieved. As a result, attempts to use gene therapy in patients’ management are more and more often undertaken. The aim of gene therapy is to replace defective genes in vivo and/or to promote the long-term endogenous synthesis of deficient protein. In vitro studies improve the production of human recombinant proteins, such as insulin (INS), growth hormone (GH), insulin-like growth factor-1 (IGF-1) and erythropoietin (EPO), which could have therapeutic application. Unfortunately, genetic methods developed for therapeutic purposes are increasingly being used in competitive sports. Some new substances (e.g., antibodies against myostatin or myostatin blockers) might be used in gene doping in athletes. The use of these substances may cause an increase of body weight and muscle mass and a significant improvement of muscle strength. Although it is proven that uncontrolled manipulation of genetic material and/or the introduction of recombinant proteins may be associated with health risks, athletes are increasingly turning to banned gene doping. At the same time, anti-doping research is undertaken in many laboratories around the world to try to develop and refine ever newer techniques for gene doping detection in sport. Thanks to the World Anti-Doping Agency (WADA) and other sports organizations there is a hope for real protection of athletes from adverse health effects of gene doping, which at the same time gives a chance to sustain the idea of fair play in sport.  相似文献   

12.
13.
Genes control biological processes such as muscle production of energy, mitochondria biogenesis, bone formation, erythropoiesis, angiogenesis, vasodilation, neurogenesis, etc. DNA profiling for athletes reveals genetic variations that may be associated with endurance ability, muscle performance and power exercise, tendon susceptibility to injuries and psychological aptitude. Already, over 200 genes relating to physical performance have been identified by several research groups. Athletes’ genotyping is developing as a tool for the formulation of personalized training and nutritional programmes to optimize sport training as well as for the prediction of exercise-related injuries. On the other hand, development of molecular technology and gene therapy creates a risk of non-therapeutic use of cells, genes and genetic elements to improve athletic performance. Therefore, the World Anti-Doping Agency decided to include prohibition of gene doping within their World Anti-Doping Code in 2003. In this review article, we will provide a current overview of genes for use in athletes’ genotyping and gene doping possibilities, including their development and detection techniques.  相似文献   

14.
Due to the attraction of optimizing the electronic structure beyond chemical synthesis, molecular doping has recently aroused wide interest in the field of organic solar cells. However, the selection of limited dopants confines its successful application. Inspired by the Lewis base characteristics of the photovoltaic materials, the Lewis acid as novel dopant is introduced in organic solar cells. In both fullerene and nonfullerene based blends, Lewis acid doping leads to increased photovoltaic performance. Detailed experiments reveal that Lewis acid doping has a synergistic effect on modifying the polymer's electronic properties and the acceptor's nanostructure even at low doping concentration, and these are simultaneously responsible for the device improvements. Based on the mechanism studies, it is proposed that the Lewis acid‐doped polymers anions produce induced dipole on the acceptor, this increases the intermolecular interaction and facilitates the morphology optimization. It is believed that the synergistic effect by Lewis acid doping greatly expands the application of doped organic solar cells, in concert with other existing methods to yield higher efficiency values.  相似文献   

15.
The recent development of high-energy LiCoO2 (LCO) and progress in the material recycling technology have brought Co-based materials under the limelight, although their capacity still suffers from structural instability at highly delithiated states. Thus, in this study, a secondary doping ion substitution method is proposed to improve the electrochemical reversibility of LCO materials for Li-ion batteries. To overcome the instability of LCO at highly delithiated states, Na ions are utilized as functional dopants to exert the pillar effect at the Li sites. In addition, Fe-ion substitution (secondary dopant) is performed to provide thermodynamically stable surroundings for the Na-ion doping. Density functional theory calculations reveal that the formation energy for the Na-doped LCO is significantly reduced in the presence of Fe ions. Na and Fe doping improve the capacity retention as well as the average voltage decay at a cutoff voltage of 4.5 V. Furthermore, structural analysis indicates that the improved cycling stability results from the suppressed irreversible phase transition in the Na- and Fe-doped LCO. This paper highlights the fabrication of high-energy Co-rich materials for high voltage operations, via a novel ion substitution method, indicating a new avenue for the manufacturing of layered cathode materials with a long cycle life.  相似文献   

16.
In response to the change of energy landscape, sodium‐ion batteries (SIBs) are becoming one of the most promising power sources for the post‐lithium‐ion battery (LIB) era due to the cheap and abundant nature of sodium, and similar electrochemical properties to LIBs. The electrochemical performance of electrode materials for SIBs is closely bound up with their crystal structures and intrinsic electronic/ionic states. Apart from nanoscale design and conductive composite strategies, heteroatom doping is another effective way to enhance the intrinsic transfer characteristics of sodium ions and electrons in crystal structures to accelerate reaction kinetics and thereby achieve high performance. In this review, the recent advancements in heteroatom doping for sodium ion storage of electrode materials are reviewed. Specifically, different doping strategies including nonmetal element doping (e.g., nitrogen, sulfur, phosphorous, boron, fluorine), metal element doping (magnesium, titanium, iron, aluminum, nickel, copper, etc.), and dual/triple doping (such as N–S, N–P, N–S–P) are reviewed and summarized in detail. Furthermore, various doping methods are introduced and their advantages and disadvantages are discussed. The doping effect on crystal structure and intrinsic electronic/ionic state are illustrated and the relationship with capacity and energy/power density is interrogated. Finally, future development trends in doping strategies for advanced SIBs electrodes are analyzed.  相似文献   

17.
Electrochemical capacitors (best known as supercapacitors) are high‐performance energy storage devices featuring higher capacity than conventional capacitors and higher power densities than batteries, and are among the key enabling technologies of the clean energy future. This review focuses on performance enhancement of carbon‐based supercapacitors by doping other elements (heteroatoms) into the nanostructured carbon electrodes. The nanocarbon materials currently exist in all dimensionalities (from 0D quantum dots to 3D bulk materials) and show good stability and other properties in diverse electrode architectures. However, relatively low energy density and high manufacturing cost impede widespread commercial applications of nanocarbon‐based supercapacitors. Heteroatom doping into the carbon matrix is one of the most promising and versatile ways to enhance the device performance, yet the mechanisms of the doping effects still remain poorly understood. Here the effects of heteroatom doping by boron, nitrogen, sulfur, phosphorus, fluorine, chlorine, silicon, and functionalizing with oxygen on the elemental composition, structure, property, and performance relationships of nanocarbon electrodes are critically examined. The limitations of doping approaches are further discussed and guidelines for reporting the performance of heteroatom doped nanocarbon electrode‐based electrochemical capacitors are proposed. The current challenges and promising future directions for clean energy applications are discussed as well.  相似文献   

18.
Precise control of carrier concentration in both bulk and thin‐film materials is crucial for many solid‐state devices, including photovoltaic cells, superconductors, and high mobility transistors. For applications that span a wide temperature range (thermoelectric power generation being a prime example) the optimal carrier concentration varies as a function of temperature. This work presents a modified modulation doping method to engineer the temperature dependence of the carrier concentration by incorporating a nanosize secondary phase that controls the temperature‐dependent doping in the bulk matrix. This study demonstrates this technique by de‐doping the heavily defect‐doped degenerate semiconductor GeTe, thereby enhancing its average power factor by 100% at low temperatures, with no deterioration at high temperatures. This can be a general method to improve the average thermoelectric performance of many other materials.  相似文献   

19.
Doping of organic bulk heterojunction solar cells has the potential to improve their power conversion efficiency (PCE). Deconvoluting the effect of doping on charge transport, recombination, and energetic disorder remains challenging. It is demonstrated that molecular doping has two competing effects: on one hand, dopant ions create additional traps while on the other hand free dopant‐induced charges fill deep states possibly leading to V OC and mobility increases. It is shown that molar dopant concentrations as low as a few parts per million can improve the PCE of organic bulk heterojunctions. Higher concentrations degrade the performance of the cells. In doped cells where PCE is observed to increase, such improvement cannot be attributed to better charge transport. Instead, the V OC increase in unannealed P3HT:PCBM cells upon doping is indeed due to trap filling, while for annealed P3HT:PCBM cells the change in V OC is related to morphology changes and dopant segregation. In PCDTBT:PC70BM cells, the enhanced PCE upon doping is explained by changes in the thickness of the active layer. This study highlights the complexity of bulk doping in organic solar cells due to the generally low doping efficiency and the constraint on doping concentrations to avoid carrier recombination and adverse morphology changes.  相似文献   

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