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311.
由于诸多因素,使得一些高血压患者对治疗产生抵抗,或表现为难治性,其中有疾病因素、对治疗的依从性、其他药物的干扰和生活方式等。研究已经证明,有效地控制血压,使之达标,可以有效地降低重要靶器官受损的危险性。而规范、系统地控制血压、加强对抵抗性高血压的管理是保护靶器官的重要途径,同时需要进一步的研究证据的支持。  相似文献   
312.
癫痫诊治中医患同盟建立的实践与策略   总被引:2,自引:0,他引:2  
通过对肝硬化者行超声检测,预测食管静脉出血,结果显示,出血组门静脉及胃左静脉管径均增粗,但胃左静脉更明显,门静脉血流速减慢而胃左静脉增快;出血组胃左静脉均呈离肝血流,其分流指数明显增大。胃左静脉的管径及血流速与门静脉比较具有显著的变化,其分流指数和血流方向在预测出血方面具有更大的价值。  相似文献   
313.
植入前组织配型孕育“救星同胞”的伦理思考   总被引:1,自引:0,他引:1  
应用植入前遗传学诊断技术在胚胎植入母体子宫前,对人类白细胞组织相容性抗原配型检测,选择与现存患儿相同HLA配型的胚胎进行受孕,孕育一个组织配型相同的脐带血干细胞供者。在某种意义上说,该项技术的应用是创造人来获得移植组织,由此引发系列伦理争议。讨论孕育"救星同胞"这一医学实践内在需要的伦理规范。  相似文献   
314.
Language evolution as a Darwinian process: computational studies   总被引:1,自引:0,他引:1  
This paper presents computational experiments that illustrate how one can precisely conceptualize language evolution as a Darwinian process. We show that there is potentially a wide diversity of replicating units and replication mechanisms involved in language evolution. Computational experiments allow us to study systemic properties coming out of populations of linguistic replicators: linguistic replicators can adapt to specific external environments; they evolve under the pressure of the cognitive constraints of their hosts, as well as under the functional pressure of communication for which they are used; one can observe neutral drift; coalitions of replicators may appear, forming higher level groups which can themselves become subject to competition and selection.
Frédéric KaplanURL: http://www.fkaplan.com
  相似文献   
315.
Speeding is a major traffic violation and time pressure is one of the leading contributors to speeding. High-speed driving requires an immediate response to perilous events from the driver to avoid a crash. Reaction time is one of the important driving performance measures to assess the driver’s response to the event. Therefore, the current study examined the influence of time pressure on reaction times of the drivers measured for two different perilous events (pedestrians crossing and obstacle overtaking). Eighty-five Indian licensed drivers participated in a driving simulation study designed for three different time pressure conditions: No Time Pressure (NTP), Low Time Pressure (LTP), and High Time Pressure (HTP). The survival analysis technique was used to model the effect of time pressure and driver characteristics with reaction times of the drivers. It was observed that drivers’ reaction times decreased by 18% and 9% in LTP and 28% and 16% in HTP during the pedestrians crossing and obstacle overtaking events, respectively. Further, 1 m/second increase in approach speed resulted in 2% and 4% reduction in reaction times of the drivers in pedestrians crossing and obstacle overtaking events, respectively. Young drivers responded 21% faster than mature drivers during the pedestrians crossing event. Interestingly, sleeping hours and physical fitness played an important role in driver’s reaction to the events. The drivers performing regular physical exercise and having minimum eight-hours of overnight sleep reacted 16% and 17% earlier in pedestrians crossing and obstacle overtaking events, respectively. The overall findings from this study showed enhanced stimulus-response behaviour of the drivers under time pressure driving conditions. The results obtained from the study can give new insight into various safety-related ITS applications.  相似文献   
316.
ObjectiveHaving learners practice a motor skill with the expectation of teaching it (versus an expectation of being tested on it) has been revealed to enhance skill learning. However, this improvement in skill performance is lost when the skill must be performed under psychological pressure due to ‘choking under pressure.’ The present study will investigate whether this choking effect is caused by an accrual of declarative knowledge during skill practice and could be prevented if a technique (analogy instructions) to minimize the accrual of declarative knowledge during practice is employed.DesignWe will use a 2 (Expectation: teach/test) x 2 (Instruction: analogy/explicit) x 2 (Posttest: high-pressure/low-pressure) mixed-factor design, with repeated measures on the last factor.MethodsA minimum of 148 participants will be quasi-randomly assigned (based on sex) to one of four groups. Participants in the teach/analogy and teach/explicit groups will practice golf putting with the expectation of teaching putting to another participant, and analogy instructions or explicit instructions, respectively. Participants in the test/analogy and test/explicit groups will practice golf putting with the expectation of being tested on their putting, and analogy instructions or explicit instructions, respectively. The next day all participants will complete low- and high-pressure putting posttests, with their putting accuracy serving as the dependent variable.  相似文献   
317.
为了解不同血糖水平下链脲佐菌素诱导鼠(STZ鼠)探究行为与学习和记忆的变化情况,把60只STZ鼠按血糖水平分成高血糖组、良好血糖组和低血糖组3组,进行延迟时间、探究时间测定和小鼠跳台试验,并与正常对照组比较。结果发现,良好血糖组与正常对照组各检测指标均相近;3组STZ鼠延迟时间、完成迷津作业时间均按血糖值递增;组间差异显著;小鼠跳台试验中高血糖组的错误数最多,24小时后错误数最少,前后差值有组间差异;延迟时间、探究时间与血糖呈显著正相关,错误数差值与血糖呈显著负相关。结果表明,高血糖鼠的探究行为和学习能力最差,但对被动回避学习的记忆保持相对较好。  相似文献   
318.
This experiment was designed to investigate the efficacy of 16 weeks of exercise training as an intervention to reduce the psychophysiological response of fire fighters to psychological stress. Fifty-three members of the Austin Fire Department (AFD) were recruited as participants and were randomly assigned to either exercise on a rowing ergometer or to continue their present modes of exercise training. Psychological stress was induced by a computerized version of the AFD Strategy and Tactics Drill (STD), in which participants responded to a simulated fire scene. Participants completed the STD prior to and following the exercise intervention. Prior to training, the groups did not differ in their cardiovascular response to the STD. Significant group differences were observed after training, in which exercise-trained participants reacted with significantly lower pulse and mean arterial pressure than their counterparts in the control condition. Exercise participants also reported significantly less stress-related state anxiety and negative affect. Exercise training appears to be a useful intervention to reduce the response to fire-related psychological stress in fire fighters.  相似文献   
319.
本研究基于人格的交互作用理论,通过时间与金钱两种助人决策情景,设计两个实验考察了人际敏感性特质对个体助人决策的影响,以及决策角色与社会压力两种情境因素在其中的作用。结果发现:(1)相比低人际敏感性,高人际敏感性个体更容易做出助人决策;(2)相比低社会压力,高社会压力下,高人际敏感性比低人际敏感性个体捐助的金钱更多; (3)高社会压力下,相比低人际敏感性个体,高人际敏感性个体为朋友与陌生人决策时会捐助更多的金钱。研究表明:人际敏感性影响个体的助人决策,决策角色与社会压力会对不同人际敏感性个体的助人决策有不同程度的影响。  相似文献   
320.
Allogeneic umbilical cord blood (UCB) donation is a pro-social behaviour directed to strangers that has a certain cost for the donor. Although the promotion of such behaviour is an important goal for many countries' health systems, little is known about the reasons that would lead to it. With this study, we explored how the impact of social closeness on altruism and trust could be related to UCB donation in a sample of new-mothers (N = 167). Participants played hypothetical Dictator and Trust games with socially close (e.g., parents) or distant (e.g., strangers) others. They donated more money to parents and siblings compared to cousins, friends and strangers and they trusted more parents, siblings and friends than cousins and strangers. Interestingly, the lower the impact of social closeness on altruism (i.e., generosity towards socially distant others), the higher the intention and the actual probability of UCB donation. A mediation analysis has shown that the relationship between social closeness on altruism and UCB donation was mediated by objective intention to donate (i.e., having followed all the procedures needed). These findings show that other-oriented motivations towards distant others might have important practical implications in identifying the targets of interventions for the promotion of UCB donation.  相似文献   
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