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91.
Previous studies demonstrated distinct cardiovascular patterns associated with threat and challenge appraisals for groups of participants. We extend these results by assessing whether appraisals continue to be associated with these cardiovascular response patterns within an individual as appraisals change. Participants completed four verbal mental arithmetic tasks for which they made appraisals before and after each task. Cardiac reactivity and total peripheral resistance (TPR) were calculated for the first and last minutes of each task, and the number of responses and percent correct were measured for each task. In line with our prediction, pretask appraisals were related to some task-related cardiac responses across the four tasks. In addition, task-related cardiovascular reactivity and behaviors both influenced appraisals following the task. Our findings suggest that an idiographic analysis of appraisals, cardiovascular physiology, and task-related behaviors provides a richer understanding of the appraisal process and reveals sex differences deserving further assessment.  相似文献   
92.
Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation.  相似文献   
93.
背景:近年来,随着全膝关节置换技术提升、手术时间缩短、术中及术后止血药的应用,其总失血量不断减少,术后引流量也逐渐减少,术后快速康复理论应运而生,引流管放置也再次成为骨科医生所热议的问题,越来越多的医生认为可以常规取消放置引流,引流似乎已可有可无。目的:旨在复习既往文献,对全膝关节置换后引流放置的相关问题归纳总结,提供围术期引流管理的相关经验。方法:检索中国知网、万方、维普、中国生物医学文献数据库等中文数据库,以及PubMed、The Cochrane Library、WebofScience、EMBASE、OVID等外文数据库,以"引流,膝关节置换术"及"totalknee arthroplasty,drainage"为检索词,检索自建库始至2020年2月为止所有与主题相关的文献,总结归纳全膝关节置换后不放置引流管围术期各方面需综合考虑的要素。结果与结论:①引流管的放置问题关乎全膝关节置换手术的最终结果,与术后出血、血肿、血栓、感染等并发症的发生关系密切;②目前全膝关节置换术后不推荐常规放置引流,但不意味着不需要管理,其实际上对临床医护在围术期各方面的管理提出更高的要求,包括但不限于术前适应证选择、手术操作、止血带使用、术中及术后药物使用、物理疗法的使用等。  相似文献   
94.
95.
目的探讨住院精神分裂症患者恢复期的心理卫生状况及心理护理干预效果。方法将76例处于恢复期的住院精神分裂症患者随机分为两组,封其中的38例追行心理谩理干预(干预组),并与对照组(未干预组)退行比较。采用SCL-90(症状自评量表)于干预前和干预后4周末造行量表抨定。枯果住院精神分裂症患者恢复期的主要心理闪题为抑郁、焦虑、人际关系、强迫、敌对、偏执等。干预组在干预后4周末SLC-90的焦虑、抑郁、人际关系3个因子分与干预前相比有非常显着性差异(P〈0.01)。强迫、敌对、偏执3个因子分有显着性差异(P〈0.05)。其他各项因子分差异无显着性(P〉0.05);而对照组各因子分干预前后相比无显着性差异(P〉0.05)。干预后两组在SCL-90的焦虑、抑郁、人际关系、强迫、敌对、偏执等6个因子分比较有显着性差异(P〈0.05)。结论心理护理干预能明显改善住院精神分裂症患者恢复期的心理卫生状况,促进病人的康复。  相似文献   
96.
Hugh  Firth Ian  Oswald 《Psychophysiology》1975,12(5):602-606
There are a number of reports suggesting an association between profusion of eye movements and active dreaming. It has however been suggested that this relationship might only be evident in comparisons across the night and would not be evident in comparisons within one REM period. Data from 20 subjects taking placebo, amylobarbitone, and nitrazepam were used to test this. Dream reports were collected from REM awakenings and rated blind as visually active or passive. Eye movement profusion (number of 2 sec epochs) was assessed for each REM period. Correlation between dream content and eye movement was low but significant in comparisons including the whole night, and including data from drug, withdrawal, and placebo conditions. A significant correlation was not consistently obtained, however, when data from each REMP were considered separately. Correlations based on data from non-drug nights only were also small and could have been due to chance effects alone. The low correlations were not explicable solely by poor reliability of content ratings. It is concluded that the relationship between visually active dreaming and eye movement is slight, and may not hold when time of night is adequately controlled.  相似文献   
97.
《Immunity》2019,50(5):1276-1288.e5
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98.
The vulnerability of epidemic process during the period of minimum annual incidence of the disease is validated. Biological properties of Shigella sonnei are studied and their variability examined using the index for evaluation of the mean number of variations for a sign. Minimum agent heterogeneity coincides with minimum incidence of disease and maximum heterogeneity with its seasonal rises.  相似文献   
99.
Douglas  Carroll  Michael G.  Harris  Gwen  Cross 《Psychophysiology》1991,28(4):438-446
Cardiac output, heart rate, stroke volume, pre-ejection period, total peripheral resistance, systolic and diastolic blood pressure, and oxygen consumption were monitored or derived in young men with mildly elevated casual blood pressures and unambiguously normotensive control subjects before, during, and after exposure to a mental arithmetic stress. Measurements were also taken while subjects underwent graded dynamic exercise. This permitted cardiac output-oxygen consumption regression equations to be calculated and, as a consequence, cardiac output during mental stress to be represented as additional cardiac output. Systolic and diastolic blood pressure were higher during all phases of the study in the mildly elevated blood pressure group. An overall groups effect during the mental stress phase of the experiment was observed for cardiac output and pre-ejection period, and the effect for stroke volume was close to significance. Significant Groups X Periods interactions were found for cardiac output and additional cardiac output, and the heart rate effect was nearly significant. Post-hoc comparisons here indicated that, in the main, group differences in these cardiac variables were more evident during the mental arithmetic stress than during the pre- and post-task baseline periods. Total peripheral resistance did not differ reliably between groups and the cardiac effects were specific to the mental stress phase of the study.  相似文献   
100.
Silent period (SP) is widely used in transcranial magnetic stimulation studies. Methodologically, SP is usually elicited at stimulus intensities corresponding to a certain percentage of corticomotor threshold. Because this approach might lead to factitious SP changes, the present study was designed to develop, in a stepwise manner, a method for investigating SP independently of corticomotor threshold. First, stimulus–response (S–R) curves of SP against stimulus intensity (SI) were constructed and quantitatively described in healthy volunteers. Second, various methodological issues such as the optimum model for describing the relationship between SP duration and SI and the importance of the type of stimulating coil were addressed. Finally, the proposed method and a commonly used method (eliciting SPs at 130% MT SI) were directly compared for a group of epileptic patients for whom administration of oxcarbazepine resulted in significant corticomotor threshold elevation. Twenty-one subjects (eleven females, median age, 38 years) were studied. SPs were obtained with a figure-of-eight coil using a standardized procedure (recording, FDI). Pilot experiments indicated that at least four trials were required, at each intensity level, to estimate the mean SP duration within 10% of the true mean. Therefore, SPs were determined from the average of four trials with 5% increments from 5 to 100% maximum SI. In a second set of experiments, SPs were obtained for fifteen subjects using a circular coil. In a third set of experiments, eight epileptic patients were studied before and after administration of oxcarbazepine (mean dose 1553 mg, range 900–1800 mg). The S–R curves were fitted to a Boltzman function and to first-order to fourth-order polynomial and sigmoid functions. The Boltzman function described the data accurately (R2=0.947–0.990). In addition, direct comparison of the six models with an F-test proved the superiority of the first. The best-fit parameters of the reference curve, i.e. the maximum and minimum values, the slope, and V50 (the SI at which SP duration is halfway between Min and Max) were 230.8±3.31 ms (x±SEM), –11.51±3.31 ms, 11.56±0.65%, and 49.82±0.65%, respectively. When the curves obtained with the circular coil were compared with those obtained with the figure-of-eight coil, there were differences between V50 (51.69±0.72 vs 47.95±0.82, P<0.001) and SP threshold (31.15 vs 24.77, P<0.01) whereas the other best-fit values did not differ significantly. Oxcarbazepine increased corticomotor threshold from 45.3±5.8% at baseline to 59.4±10.4% (P<0.001). According to the commonly used method, the drug significantly prolonged SP (from 117.6±42.4 ms to 143.5±46.5 ms, P<0.001) and, consequently, enhanced brain inhibition. In contrast, study of the SP curves led to the conclusion that oxcarbazepine does not affect the Max value and slope but significantly increases V50 and SP threshold (from 54.5±4.9% to 59.9±7.2% and from 29.1±6.4% to 34.6±6.8%, respectively, P<0.01). These findings imply that oxcarbazepine does not enhance brain inhibitory mechanisms. Thus, in situations characterized by significant changes in corticomotor threshold the proposed method provides results clearly different from a commonly used approach. It is concluded that S–R curves obtained with a figure-of-eight coil in 5% increments and fitted to a Boltzman function provide an accurate, comprehensive, and clinically applicable method for exploring SP.Presented in part at the meeting of the EFNS, Helsinki, September 2003  相似文献   
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