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41.
探讨平板运动试验(TET)结合颈动脉斑块检测在诊断冠心病的临床意义。对166例疑诊冠心病患者进行冠状动脉造影(CAG),TET,颈动脉斑块检查,以CAG的诊断结果为金标准,分析TET,颈动脉斑块检查,TET结合颈动脉斑块检查诊断冠心病的敏感度、特异度。比较三者诊断冠心病的敏感度、特异度。三者敏感度分别为71.4%、64.3%、96.0%。特异度分别为65%、60.0%、82.4%。后者较前两者敏感度、特异度P<0.05。TET结合颈动脉斑块检查可显著提高冠心病的诊断率,不失为CAG前的筛选方法。  相似文献   
42.
This research aimed to investigate the time course effect of a moderate steady-state exercise session on response execution and response inhibition using a stop-task paradigm. Ten participants performed a stop-signal task whilst cycling at a carefully controlled workload intensity (40% of maximal aerobic power), immediately following exercise and 30 min after exercise cessation. Results showed that moderate exercise enhances a subjects’ ability to execute responses under time pressure (shorter Go reaction time, RT without a change in accuracy) but also enhances a subjects’ ability to withhold ongoing motor responses (shorter stop-signal RT). The present outcomes reveal that the beneficial effect of exercise is neither limited to motor response tasks, nor to cognitive tasks performed during exercise. Beneficial effects of exercise remain present on both response execution and response inhibition performance for up to 52 min after exercise cessation.  相似文献   
43.
There might not be a specific nano-ethics, but there definitely is an ethics of new & emerging science and technology (NEST), with characteristic tropes and patterns of moral argumentation. Ethical discussion in and around nanoscience and technology reflects such NEST-ethics. We offer an inventory of the arguments, and show patterns in their evolution, in arenas full of proponents and opponents. We also show that there are some nano-specific issues: in how size matters, and when agency is delegated to smart devices. Our overall approach is a pragmatist ethics, and we conclude that struggle (and learning) might be more productive than models emphasizing consensus.
Tsjalling SwierstraEmail:
  相似文献   
44.
The Eysenck Personality Questionnaire-Revised (EPQ-R), the Eysenck Personality Profiler Short Version (EPP-S), and the Big Five Inventory (BFI-V4a) were administered to 135 postgraduate students of business in Pakistan. Whilst Extraversion and Neuroticism scales from the three questionnaires were highly correlated, it was found that Agreeableness was most highly correlated with Psychoticism in the EPQ-R and Conscientiousness was most highly correlated with Psychoticism in the EPP-S. Principal component analyses with varimax rotation were carried out. The analyses generally suggested that the five factor model rather than the three-factor model was more robust and better for interpretation of all the higher order scales of the EPQ-R, EPP-S, and BFI-V4a in the Pakistani data. Results show that the superiority of the five factor solution results from the inclusion of a broader variety of personality scales in the input data, whereas Eysenck's three factor solution seems to be best when a less complete but possibly more important set of variables are input.  相似文献   
45.
Nationalist and ethnic conflicts are a continuing source of tension in the post–Cold War period. The underlying factors affecting such conflicts are threat perception, ethnic security dilemmas, and lack of trust between nationalist/ethnic groups. The challenge is to find solutions to these conflicts. International institutions can establish trust and reduce the ethnic security dilemma by providing multiple forums of representation, promoting overlapping identities, and pooling sovereignty. Pooling sovereignty across a number of international representative bodies leads to increased access to governmental policymaking, with each party having a stake in government, and leads to a reduction in political tension and conflict. Thus, international parliamentary institutions may provide a solution to these conflicts. The British-Irish Peace Agreement (Good Friday Agreement) of 1998 is examined as an illustration of this argument.  相似文献   
46.
羧化不全骨钙素(ucOCN)是骨中成骨细胞分泌的特异性蛋白,因其在调控神经发育、神经可塑性等中的重要角色而受到神经科学领域关注。"骨-脑"串联"对话"是骨内分泌-神经介导的应答系统,ucOCN透过血脑屏障后介导单胺类神经递质、神经内分泌、神经免疫、神经再生及基因表达等机制,进而作用于海马CA3区、扣带回等脑区功能发挥来调节抑郁发生及改善。而ucOCN作为骨源性力学刺激敏感基因,运动上调其表达后进入血液循环,通过介导5-HT/GABA分泌、HPA轴功能、炎症反应、神经营养因子(BDNF等)表达或信号途径(如GSK3β/β-catenin、TLR4/miR-223/NLRP3等)激活等来实现"骨串联脑",发挥运动抗抑郁作用。通过对骨源性因子ucOCN介导脑区功能变化从而实现运动抗抑郁的作用机制进行探讨、梳理,一方面有助于更深入了解骨内分泌功能,另一方面为抑郁发生、改善和运动抗抑郁研究提供新的理论基础和研究思路。  相似文献   
47.
心血管事件成为威胁民航飞行安全的主要因素之一.为更及时地发现飞行员冠状动脉病变,提高用无创性常规辅助检查预测飞行员冠状动脉粥样硬化的准确性,对105例飞行员进行血脂、血压、血糖、体重指数、颈动脉彩色多普勒超声检查、运动负荷心电图试验以及64排双源CT冠状动脉造影检查.比较颈动脉粥样硬化与运动负荷心电图试验阳性、高危因素对冠状动脉预测的敏感性和特异性.飞行员的职业特点可能使其冠状动脉粥样硬化早于其他血管床,危险因素较其他辅助检查可能更具意义,必须综合分析各项检查才可能更准确地预测飞行员冠状动脉病变.  相似文献   
48.
The effects of a variable-ratio schedule of reinforcement on pedaling a stationary exercise bicycle were examined. Three obese and three nonobese 11-year-old boys were individually tested five times weekly for approximately 12 weeks. A changing-criterion design was used in which each successive criterion was increased over mean performance rate in the previous phase by approximately 15%. The contingencies of the successive criteria resulted in systematic increases in rate of exercise for all children. Final variable-ratio rates were higher than those under fixed ratios found in previous research, with rates for 2 of the 3 obese boys approximating those of the nonobese.  相似文献   
49.
Inclusive instruction was provided for three older adults with profound mental retardation in a water exercise class at a local YMCA. The older adults were taught to exercise through the use of systematic prompting. A multiple baseline design across participants with an embedded reversal was used to evaluate the impact of a personal trainer. The three participants performed the exercise, but regressed without the assistance of the trainer, as demonstrated by the reversal. Data collected during peer prompting and maintenance conditions indicated that the participants continued to exercise at levels higher than baseline but lower than with a personal trainer.  相似文献   
50.
Two single-subject experiments were conducted in public school classrooms for severely emotionally disturbed children. Both experiments investigated the effects of a treatment requiring a child to exhibit a simple exercise task after a verbal or aggressive response, using reversal and multiple-baseline designs. The independent variable, contingent exercise, required standing up and sitting on the floor five to ten times contingent on an inappropriate behavior. It was found that contingent exercise was easy to carry out, and following it, the child quickly returned to the learning task that had been interrupted by the inappropriate behavior. The contingent exercise procedure required a minimum of prompting or manual guidance. Although contingent exercise was not topographically related to the inappropriate response, it decreased those responses dramatically. The results suggested that contingent exercise was not only more powerful than DRO but also could be administered independently. It was concluded that contingent exercise may constitute an alternative procedure that can be used by therapists confronted with severely abnormal behaviors. It would appear to be particularly relevant in settings where procedures such as timeout and painful consequences find restricted use. Finally, a number of guidelines have been proposed as a safeguard against the misuse of this mild but powerful procedure.  相似文献   
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