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ThetoleranceofthemudskipperBoleophthalmusboddaertitocyanideishigherthanthoseofotherfishes[1].Suchahightolerancetocyanidedoesnotinvoveareductionofmetabolicrateoranenhancedanaerobicmetabolism,oracyanide-insensitiverespiratorypathway.Instead,itisaresultofthepresenceofasurplusofcytochromeoxidaseandinduciblecyanide-detoxifyingmechanisms,tumingcyanideinthiocyanate,inthismudskipper[1].ThoughCN-isdetoxifiedtoSCN-,realizingbiomembranesaremorepermeabletoHCNthanCN-,wedecidedtoinvestigateiftheprotondi… 相似文献
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Hillman CH Belopolsky AV Snook EM Kramer AF McAuley E 《Research quarterly for exercise and sport》2004,75(2):176-185
Electrocortical and behavioral responses of low, moderate, and high physically active older adults were compared with a younger control group on neutral and incompatible conditions of a flankers task. Compared to younger adults, high and moderate active older adults exhibited increased event-related potentials component P3 amplitude for the incompatible condition at the frontal electrode site. For the neutral condition, only low active older adults exhibited decreased amplitude at the central-parietal site, compared to younger adults. P3 latency revealed the longest latencies for low active older adults, followed by moderate active, high active, and younger adults, respectively. Reaction time (RT) data revealed that younger adults exhibited faster RT compared to all three older groups. Results suggest that physical activity may improve executive control function in older adults by affecting the distribution of P3 amplitude, which has been related to memory and attentional processes, and by decreasing P3 latency, which relates to the speed of cognitive processing. 相似文献
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这部分的研究目标是对游泳选手划水的各种熟练技能在三度空间里进行分析。所要进行的力量计算,关键在于他们的划臂动作。我们利用手的运动座标给我们表示出手的速率的大小,后掠角度和倾斜角度。函数方程式1和2: L=1/2pV~2C_CS D=1/2pV~2C_DS是可以成立的。这样,力量的计算便是可能的。 方法 分析影片步骤:运用二轴性的技巧获得电影资料。以俯视面和侧视面作为主要的观察平面。通过 相似文献
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Culture not only justifies the existence of libraries but also determines the level of funding libraries receive for development. Cultural appreciation of the importance of libraries encourages their funding; lack of such appreciation discourages it. Medical library development is driven by culture in general and the culture of physicians in particular. Nineteenth-century North American medical library funding reflected the impact of physician culture in three phases: (1) Before the dawn of anesthesia (1840s) and antisepsis (1860s), when the wisdom of elders contained in books was venerated, libraries were well supported. (2) In the last third of the nineteenth century, as modern medicine grew and as physicians emphasized the practical and the present, rather than books, support for medical libraries declined. (3) By the 1890s, this attitude had changed because physicians had come to realize that, without both old and new medical literature readily available, they could not keep up with rapidly changing current clinical practice or research. Thus, "The Medical Library Movement" heralded the turn of the century. 相似文献
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The aim of this study was to determine the physiological responses to orienteering by examining the interrelationships between the information provided by a differential global positioning system (dGPS) about an orienteer's route, speed and orienteering mistakes, portable metabolic gas analyser data during orienteering and data from incremental treadmill tests. Ten male orienteers completed a treadmill threshold test and a field test; the latter was performed on a 4.3 km course on mixed terrain with nine checkpoints. The anaerobic threshold, threshold of decompensated metabolic acidosis, respiratory exchange ratio, onset of blood lactate accumulation and peak oxygen uptake (VO2peak) were determined from the treadmill test. Time to complete the course, total distance covered, mean speed, distance and timing of orienteering mistakes, mean oxygen uptake, mean relative heart rate, mean respiratory exchange ratio and mean running economy were computed from the dGPS data and metabolic gas analyser data. Correlation analyses showed a relationship between a high anaerobic threshold and few orienteering mistakes (r = - 0.64, P < 0.05). A high threshold of decompensated metabolic acidosis and VO2peak were related to a fast overall time (r = -0.70 to -0.72, P < 0.05) and high running speed (r = 0.64 to 0.79, P < 0.05 and P < 0.01, respectively), and were thus the best predictors of performance. 相似文献
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Connor E 《Medical reference services quarterly》2002,21(4):1-14
Chat reference refers to the use of instant messaging and call center software to support interactive text or voice communication with library patrons. Instant messaging has been integrated into many e-commerce environments, and into the social lives of many teenagers and young adults, affording a level of immediacy and intimacy not possible with e-mail applications. The convergence and interoperability of new and emerging technologies can be used to develop new communities of users that view libraries as being essential to their education, patient care, and research activities. 相似文献