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951.
This study assessed plasticity of inhibition in older adults through examining retest practice effects in a six-session training paradigm using the Stroop task and the training-induced transfer effects to a range of cognitive measures. Fifty-six older adults (aged 60-84 years, mean = 71.05, standard deviation = 6.17) participated in this study. They were evenly assigned to one of four groups: summary feedback, individualized and adaptive feedback, no-feedback, or a no-contact control group. The results suggest that older adults are able to improve inhibition across retest sessions but unable to transfer the retest practice effects to other tasks. In addition, the improvement is not item specific and feedback does not appear to moderate the magnitude of the training benefits; however, feedback does appear to reduce interference variance across retest practice sessions. (PsycINFO Database Record (c) 2012 APA, all rights reserved). 相似文献
952.
This study examined whether the nonitem-specific retest learning effects, previously shown with young-old adults primarily in their 60s and 70s, could be extended to oldest-old adults aged 80 and onward. Twenty-one oldest-olds participated in an 8-session retest training program with three ability domains: perceptual speed, inductive reasoning, and visual attention. Their data were compared with the data of 30 young-olds collected in a previous work (Yang, Reed, Russo, & Wilkinson, 2009). The two age groups showed largely equivalent retest learning effects. In addition, only young-olds were able to benefit from item-specific retest learning, specifically in reasoning and perceptual speed tests. (PsycINFO Database Record (c) 2012 APA, all rights reserved). 相似文献
953.
Stress induces cardiac dysfunction and cardiomyocyte injury, and while current data indicate that mitochondria play a key role in this process, the mechanisms remain unknown. In this study, we found that in rats, restraint stress induced nerve growth factor-induced clone B (NGFI-B) translocation from the nucleus to mitochondria in cardiomyocytes. This translocation promoted cytochrome c release from mitochondria to the cytoplasm, which ultimately resulted in cardiomyocyte apoptosis. We also found that stress induced oversecretion of glucocorticoids and activated the protein kinase A (PKA) pathway in cardiomyocytes. Enhanced PKA activity increased NGFI-B serine phosphorylation, which caused NGFI-B to translocate from the nucleus to mitochondria. Moreover, a PKA peptide inhibitor blocked NGFI-B serine phosphorylation and translocation. Our data demonstrate that stress affects cardiomyocytes by inducing NGFI-B mitochondrial translocation via serine phosphorylation, which in turn initiates mitochondrial-mediated apoptosis. 相似文献
954.
This study aimed to explore the physiological and psychological impacts on male medical interns during on-call duty (OCD). A prospective study of 13 medical interns was carried out using repeated testing during an on-call internal medicine and a duty-free course. There are 10 OCDs per month and each duty is composed of 33.5 consecutive work hours followed by 2 duty-free days for a time period of 3 months. Spectral analysis of R-R intervals was performed to evaluate the participants' heart rate variability. Among the three main spectral components distinguished, a high-frequency (HF) component of 0.15-0.4 Hz and a low-frequency component (LF) of 0.04-0.15 Hz were analyzed. The ratio of LF and HF (LF/HF) was also calculated. Reduced LF/HF, which suggests reduced cardiac sympathetic modulation, was found during duty night work. Increased HF was identified during the first sleep after OCD, which corresponded to the sleepiness scales. The OCD causes temporary emotional influence by the findings of higher anxiety and depression scores. In addition, inattention and impulsiveness, as represented by the continuous performance test score and lower nocturnal sympathetic modulation, were found, which indicated the differences between the internal medicine course and duty-free course. Our study suggests that 10 stressful on-call duties monthly result in reduced sympathetic modulation during duty night work, high anxiety and depression state, and a persistent inattention. 相似文献
955.
The study aims to help characterize the sort of structures about which people can acquire unconscious knowledge. It is already well established that people can implicitly learn n-grams (chunks) and also repetition patterns. We explore the acquisition of unconscious structural knowledge of symmetry. Chinese Tang poetry uses a specific sort of mirror symmetry, an inversion rule with respect to the tones of characters in successive lines of verse. We show, using artificial poetry to control both n-gram structure and repetition patterns, that people can implicitly learn to discriminate inversions from non-inversions, presenting a challenge to existing models of implicit learning. 相似文献
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This study investigates the mechanisms that explain why person–organization (PO) fit impacts organizational attraction. Adopting Edwards and Cable’s (2009) approach, an integrative model is developed around the idea that experiencing value congruence during the recruitment process perpetuates certain expectations about future work environments and employer relationships. These expectations in turn have a positive impact on organizational attraction. Evidence from a longitudinal study on a sample of job seekers suggests that expected opportunities for value expression and need fulfillment offered the most viable explanations of value congruence effects. The implications of important observed differences in the experience of PO fit between job seekers and full-time employees are discussed. 相似文献
960.
探讨鼻烟窝皮瓣在修复拇指大面积皮肤缺损中的方法和治疗效果。从2008年1月~2013年10月间应用桡动脉在解剖鼻烟窝穿支为血管蒂的鼻烟窝皮瓣,逆行修复拇指大面积皮肤缺损26例,年龄17岁~55岁。术后平均随访时间25个月,皮瓣全部成活。皮瓣色泽及质地与健侧拇指背侧皮肤相近,拇指活动度基本正常。因此,鼻烟窝皮瓣是一种简便经济、效果理想、患者易于接受的术式,适合应用于拇指大面积皮肤缺损的治疗。 相似文献