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281.
Hypertension is estimated to cause 12.8% of all deaths worldwide. Both literature and well-supported cognitive models indicate that hopelessness predicts depressive symptoms. This study aimed to test whether high levels of hopelessness are associated with increased blood pressure, as well as whether depression acts as a mediator between hopelessness and blood pressure. Data from the original 24-year longitudinal Baltimore Epidemiologic Catchment Area Study (ECA) were analyzed via linear regression (N = 917; 60.3% female; 62.9% European American; mean age = 42.96 years, SD = 16.94). Hopelessness was found to have a significant direct relationship with systolic blood pressure (SBP, p < .05), but not with diastolic blood pressure (DBP, p > .05); while depression had no significant direct relationship with SBP or with DBP. Overall, findings indicated that hopelessness has a significant relationship with SBP. Limitations and implications are discussed.  相似文献   
282.
Using data on about 35,000 professional tennis matches, we test whether men and women react differently to psychological pressure arising from the outcomes of sequential stages in a competition. We show that, with respect to men, women losing the first set are much more likely to play poorly the second set. This suggests that women are more discouraged when facing the pressure of falling behind and receiving negative feedback. The gender differential is stronger in high-stake matches. On the other hand, when players are tied in the third set we do not find any gender difference in players’ reactions suggesting that women are as able as men to handle pressure if they do not lag behind. These results are robust controlling for measures of abilities and fitness of players, such as players’ rankings, players’ ex-ante winning probability, players’ rest, monetary prizes, players’ and tournaments’ fixed effects.  相似文献   
283.
Navigating large-scale environments involves dynamic interactions between the physical world and individuals’ knowledge, goals, and strategies. Time pressure can result from self-imposed goals or relatively dynamic situational factors that induce varied constraints. While time pressure is ubiquitous in daily life and has been shown to influence affective states, cost-benefit analyses, and strategy selection, its influence on navigation behaviour is unknown. The present study examined how introducing varied time constraints during virtual urban navigation would influence spatial strategies and impact the efficiency and effectiveness of goal-directed wayfinding. Participants learned a large-scale urban virtual environment by wayfinding between a series of 20 successive landmark goals (e.g., You have reached the Theater. Now find the Bank.). A day later, they again performed the same task, but landmark-to-landmark trials were characterized by conditions of low-, moderate-, or high-pressure time limits as quantified by a pilot experiment. As time pressure increased, participants more likely navigated along previously experienced paths and less likely travelled in the global direction of the destination. Results suggest strategy shifts under time constraints that increase reliance on egocentric, route-based strategies and decrease reliance on global configural knowledge, probably in an attempt to reduce cognitive demands and support performance under pressure.  相似文献   
284.
高血压是由多种病因和发病机制引起的一种慢性疾病,可以导致多种靶器官功能损害,并最终导致严重的心、脑血管并发症,危及人类的健康和生命。如何做到有效的预防和治疗是目前面,临的问题。本文分析了高血压控制的现状,以矛盾的特殊性原理为指导,从高血压的病因和发病机制、临床特点以及药物对个体的敏感性等诸多方面出发,阐述了高血压患者个体差异性。高血压患者个体差异性决定每一个个体综合控制策略的不同,运用“具体问题具体分析”的方法,为每一个个体制定个体化的血压控制方案,以期达到理想的高血压整体控制水平。  相似文献   
285.
To examine extended control over local choice, the present study investigated preference in transition as food‐rate ratio provided by two levers changed across seven components within daily sessions, and food‐amount ratio changed across phases. Phase 1 arranged a food‐amount ratio of 4:1 (i.e., the left lever delivered four pellets and the right lever one pellet); Phase 2 reversed the food‐amount ratio to 1:4, and in Phase 3 the food‐amount ratio was 3:2. At a relatively extended time scale, preference was described well by a linear relation between log response ratio and log rate ratio (the generalized matching law). A small amount of carryover occurred from one rate ratio to the next but disappeared after four food deliveries. Estimates of sensitivity to food‐amount ratio were around 1.0 and were independent of rate ratio. Analysis across food deliveries within rate‐ratio components showed that the effect of a small amount was diminished by the presence of a large amount—that is, when a larger amount was present in the situation (three or four pellets), the value of a small amount (one or two pellets) became paltry. More local analysis of visits to the levers between food deliveries showed that postfood visits following a large amount were disproportionately longer than following a small amount. Continuing food deliveries from the same source tended to make visits less dependent on relative amount, but a discontinuation (i.e., food from the other lever) reinstated dependence on relative amount. Analysis at a still smaller time scale revealed preference pulses following food deliveries that confirmed the tendency toward dependence on absolute amount with continuing deliveries, and toward dependence on relative amount following discontinuations. A mathematical model based on a linear‐operator equation accounts for many of the results. The larger and longer preference following a switch to a larger amount is consistent with the idea that local preference depends on relatively extended variables even on short time scales.  相似文献   
286.
In an orthostatic challenge, Cambodian patients with orthostatic panic in the last month (OP patients) sometimes panicked during orthostatic challenge, whereas those without orthostatic panic in the last month (NOP patients) did not. Also, OP patients with primarily dizziness during orthostatic challenge panic (OPOCP-D) had a less vigorous physiological response than two other groups: (a) OP patients with primarily palpitations during orthostatic challenge panic (OPOCP-P) and (b) NOP patients who had no symptoms during orthostatic challenge (NOPNOCP-NS). Among the patients experiencing orthostatic challenge–induced panic (i.e., the OPOCP-D and OPOCP-P patients), there were prominent orthostatic challenge–induced flashbacks and catastrophic cognitions, and the severity of orthostatic challenge–induced flashbacks and catastrophic cognitions correlated with the severity of orthostatic panic in the previous month and with the severity of orthostatic challenge–induced panic.  相似文献   
287.
田芊  张雷  孙时进 《心理科学》2019,(3):681-687
摘 要 择偶是婚姻过程中一个非常重要的环节,女性择偶是近年来研究的热门话题。本研究从进化心理学的择偶理论出发,研究女性在经济压力之下的择偶偏好。研究用实验的方法,结果表明(1)女性在经济压力之下,更青睐具有“好资源”的男性(2)对照组女性在外显测量的情况下往往表示更喜欢男性的“好爸爸”特质,而在阈下测量时,无论哪一组的女性都更重视男性的社会经济地位。研究结果表明,女性择偶时普遍更重视资源线索,在经济压力之下,这种择偶偏好更加明显。  相似文献   
288.
For older adults, falls often occur when transitioning from motion to a complete stop, as the motor control required during this phase is very complex and challenging. The purpose of this study was to clarify the effect of aging on the motor control required to terminate motion. Twenty-five healthy older adults (aged >65 years) and 25 healthy young adults (20–23 years) performed a rapid stopping task while standing on a force plate. The rapid stopping task was conducted by analyzing center of pressure (COP) on the force plate during a visually guided tracking experiment. To assess the ability to terminate motion, we measured the velocity waveform for the COP, along with the reaction, propulsion, braking, and total movement times. Both the reaction and movement times of the older-adult group were significantly longer than those of the younger-adult group (all, p < 0.05). There was no significant difference between the groups in regard to the initial backward propulsion time; however, in the subsequent sequence of backward braking, forward propulsion, and backward braking, all times were longer in the older-adult group than in the younger-adult group (p < 0.05). Our results show that the series of time delays shown by older adults when initiating and terminating motion is due to not only delayed reactions but also delayed stopping. Furthermore, our findings suggest that older adults have not only a diminished propulsion ability but also a diminished braking ability.  相似文献   
289.
择偶是婚姻过程中一个非常重要的环节,女性择偶是近年来研究的热门话题。从进化心理学的择偶理论出发,研究女性在经济压力之下的择偶偏好。使用自由回忆法对女性择偶偏好进行测量,结果表明:(1)女性在经济压力之下,更青睐具有“好资源”的男性;(2)无论哪一组的女性都更重视男性的社会经济地位。研究结果表明,女性择偶时普遍更重视资源线索,在经济压力之下,这种择偶偏好更加明显。  相似文献   
290.
肺保护策略机械通气的再评价   总被引:1,自引:0,他引:1  
通常认为急性肺损伤/急性呼吸窘迫综合征(ALI/ARDS)患者应用肺保护策略机械通气可降低病死率,主要由于潮气量的降低。对已发表的随机对照研究再次分析,发现平台压与患者病死率明显相关。平台压低于30cmH2O时,潮气量可以在一定范围内增加,不影响患者预后。但选择小潮气量可能对病人有害。随机对照研究在试验设计、统计学分析、病人同质性等方面依然存在很多问题。从现有资料看,潮气量和平台压都很重要。  相似文献   
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