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91.
应用24h动态血压监测(ABPM)了解老年原发性高血压晨峰现象对主要靶器官结构及功能的潜在损害。114例老年原发性高血压患者根据24h动态血压监测分为晨峰组和非晨峰组,均常规检查血脂谱,空腹血糖,放免法测定尿微量白蛋白,计算体重指数(BMI)、左室质量指数(LVMI)、颈总动脉(CCA-IMT)和颈内动脉内膜中层厚度(ICA-IMT)、心电图测量计算QT离散度(QTcd)。晨峰组的24h、白昼、夜间平均收缩压均显著高于非晨峰组动态血压监测水平(P<0.05),而且晨峰组的睡-谷晨峰变异幅度增高有统计学意义(P<0.05)。晨峰组的LVMI、CCA-IMT、ICA-IMT、QTcd和尿微量白蛋白指标均高于非晨峰组(P<0.01)。两组在BMI、血脂谱、血糖差异无统计学意义。清晨高血压是老年原发性高血压病的一个不可忽视的潜在危险因素。长期晨间血压负荷升高使得机体全天处于血压高负荷状态,更易使心肌重构肥厚和心电生理特征改变,增加心律失常发生率;加速动脉粥样硬化斑块形成。因此遏制老年原发性高血压患者的晨峰高反应是降压达标和减缓靶器官损害的关键环节。  相似文献   
92.
靶控输注技术作为一种新兴的静脉给药方法,凭借其独特的优势已广泛的应用于临床麻醉,但个体差异的存在使靶控输注技术的应用受到局限。通过对病人个体差异的哲学分析,阐述个体差异对靶控输注技术的影响。并就克服个体差异的影响,提出了靶控输注技术的个体化应用。  相似文献   
93.
在返回抑制范式下 ,利用线索—靶子模式进行了两个实验 ,以大学生为被试 ,以重复线索化次数来操纵线索化阶段的注意 ,以靶子的注意定向来操纵靶子加工阶段的注意 ,探讨注意对返回抑制的影响。实验一采用连续线索化方式 ,发现当靶子为自主性注意定向时 ,线索化次数对返回抑制有显著影响 ,线索化 3次时返回抑制值大于线索化 1次和 2次 ;当靶子为反射性注意定向时 ,线索化次数对返回抑制无影响。实验二采用交叉线索化方式 ,发现线索化次数对返回抑制的影响正好与实验一相反。两个实验一致表明 ,无论是线索化阶段的注意 ,还是靶子加工阶段的注意 ,均对返回抑制有显著影响 ;并且 ,在对返回抑制的影响上 ,二者存在显著交互作用。从而支持注意影响返回抑制的观点。该结果对返回抑制的机制研究有一定意义。  相似文献   
94.
Given the widening gap between the number of individuals on transplant waiting lists and the availability of donated organs, as well as the recent plateau in donations based on neurological criteria (i.e., brain death), there has been a growing interest in expanding donation after circulatory determination of death. While the prevalence of this form of organ donation continues to increase, many thorny ethical issues remain, often creating moral distress in both clinicians and families. In this article, we address one of these issues, namely, the challenges surrounding patient and surrogate informed consent for donation after circulatory determination of death. First we discuss several general concerns regarding consent related to this form of organ donation, and then we address additional issues that are unique to three different patient categories: adult patients with medical decision-making capacity or potential capacity, adult patients who lack capacity, and pediatric patients.  相似文献   
95.
The specific movement demands of soccer that are linked to post-match recovery and readiness to train are unclear. Therefore, we examined the relationship between Global Positioning System (GPS) variables and the change (Δ; from baseline) in Creatine Kinase (CK) concentrations and peak power output (PPO; during the countermovement jump) at 24 h and 48 h post-match. Fifteen English Premier League reserve team players were examined over 1–4 matches. Measurements of CK and PPO were taken before (24 h prior to match-play) and after (+24 h and +48 h) each game during which movement demands were quantified using 10 Hz GPS data. High intensity distance covered (r = 0.386, p = 0.029; r = −0.349; p = 0.050), high intensity distance covered⋅min−1 (r = 0.365, p = 0.040; r = −0.364, p = 0.040), high speed running distance (r = 0.363, p = 0.041; r = −0.360, p = 0.043) and the number of sprints⋅min−1 (r = 0.410, p = 0.020; r = −0.368, p = 0.038) were significantly related to ΔCK and ΔPPO at +24 h post-match, respectively. No relationships were observed between any match variables and ΔCK and ΔPPO after +48 h of recovery. These findings highlight that high intensity match activities are related to ΔCK and ΔPPO in the 24 h, but not 48 h, following soccer match-play. Such information is likely of interest to those responsible for the design of soccer player’s training schedules in the days following a match.  相似文献   
96.
Tungsten (W) is cited as a candidate first-wall material in fusion reactors owing to its outstanding thermal properties and erosion resistance. An important issue is that the energetic isotopes of hydrogen, tritium (T) and deuterium (D) and helium (He) particles damage the surface of W in fusion reactors. He particles cause more notable damage than D or T because the binding energy of defects and He is larger than that of defects and D or T. In this study, well-annealed W specimens were implanted with 5 keV He ions at room temperature and irradiation dosages of 1.0 × 1020 and 2.5 × 1021 ions/m2. Then, thermal desorption spectroscopy analysis was performed by heating the samples to 1973 K at a ramping rate of 0.5 K/s. Thermal desorption of He in the sample irradiated with a low dosage occurred at 1400 and 1960 K, whereas that in the sample irradiated with a high dosage occurred at 740, 1050 and 1500 K. According to the microstructures observed using transmission electron microscopy, both peaks in the former case were attributed to He de-trapping from irradiation to nduced helium-vacancy clusters of different sizes, whereas the peaks in the latter case were attributed to He de-trapping from surface defects, irradiation-induced dislocation loops and tiny helium-vacancy clusters, respectively.  相似文献   
97.
A remarkable ability of the human visual system is the implementation of attentional control settings (ACSs) that govern what stimuli capture or hold attention. We provide evidence that ACSs can be specified by episodic long-term memory representations. In all experiments, participants memorized 30 images of objects that they then monitored for in an attention task, inducing an episodic-based ACS. In Experiments 1a and 1b, only studied cues in a cueing task captured attention. We confirmed these cueing effects reflect capture by testing for inhibition of return in Experiment 2a, and controlled for perceptual masking by cues in Experiment 2b. In Experiment 3 we determined that ACSs are specifically supported by episodic retrieval, by dividing studied images into two sets and designating one as the targets in a rapid serial visual presentation task: Only target-set matching distractors produced a spatial blink (captured attention). These results extend our understanding of the representations specifying ACSs.  相似文献   
98.
从信任违背到信任修复:道德情绪的作用机制   总被引:1,自引:0,他引:1  
早期学者已经从认知的角度分析信任违背的原因及修复方式。近年来,情绪对信任修复的影响引起了重点关注,但是情绪在其中的作用机制并未得到解答。当前的研究主要从情绪影响信任的线索依赖效应和离散情绪(内疚、羞愧、愤怒、悲伤等)对信任修复的影响这两个角度着手研究情绪对信任修复的影响。通过文献梳理发现内疚和共情两种道德情绪是影响信任修复最重要的情绪因素:内疚能够促进受信方做出补偿行为,共情能够促进信任方宽恕他人。基于此构建了道德情绪的信任修复模型,并考虑了目标线索和信任方的特质性宽恕的调节作用。同时建议未来的研究进一步探讨其他离散情绪尤其是道德情绪对信任修复的作用,并关注情境与情绪的交互作用。  相似文献   
99.
Target onsets in dynamically changing displays can be predicted when contingencies exist between different stimulus states over time. In the present study, we examined predictive monitoring when participants searched dynamically changing displays of numbers and colored squares for a color target, a number target, or both. Stimuli were presented in both contiguous and discrete spatial configurations. Response time (RT) and accuracy were recorded, and evidence of predictive monitoring was assessed via first fixations and refixations of target‐predictive stimuli. RTs to target onsets and evidence of predictive monitoring were reduced in dual‐target, relative to single‐target, conditions. Further, predictive monitoring did not speed RTs but was influenced by display configuration. In particular, discrete displays impaired monitoring for number targets in the dual‐target condition. Implications exist for real‐world visual tasks involving multiple target categories and for visual display design.  相似文献   
100.
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