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221.
采用S-P法检测17例HT患者甲状腺组织切除标本和9例正常甲状腺组织标本中ES、iNOS及bFGF的表达并分析其之间的相关性,以探讨三者在HT发生发展中的作用.结果HT组中ES、iNOS及bFGF的表达程度均明显高于正常组(P均<0.05),其中ES与bFGF表达无显著相关性(P>0.05),ES与iNOS、bFGF与iNOS的表达均呈显著正相关(r=0.531,r=0.723,P均<0.05).结论为在HT中,高表达的ES、iNOS及bFGF在其发生和发展中可能具有重要作用,为研究其病理生理变化和发病机理提供了理论依据.  相似文献   
222.
We define a multi-modal version of Computation Tree Logic (ctl) by extending the language with path quantifiers E δ and A δ where δ denotes one of finitely many dimensions, interpreted over Kripke structures with one total relation for each dimension. As expected, the logic is axiomatised by taking a copy of a ctl axiomatisation for each dimension. Completeness is proved by employing the completeness result for ctl to obtain a model along each dimension in turn. We also show that the logic is decidable and that its satisfiability problem is no harder than the corresponding problem for ctl. We then demonstrate how Normative Systems can be conceived as a natural interpretation of such a multi-dimensional ctl logic. Presented by Jacek Malinowski  相似文献   
223.
This study examined the relationship between heart rate variability (HRV), as an index of individual differences in emotion regulation, and perception of other-blame, as a mechanism of anger induction. The physiological responses were recorded while subjects read a story from a computer screen. The story narrated a negative event in self-referred way -dismissal from a job as the result of a colleague’s action- under conditions of intentionality versus non-intentionality. Cognitive and emotional variables were assessed by questionnaire immediately after the physiological test. The resulting structural model supports the conclusion that HRV exerts its regulatory influence directly on perception of other-blame rather than on emotion. In situations of intentionality, individuals with higher HRV make less extreme evaluation of the offender’s blame, versus those with lower HRV, thus leading to a reduction in anger reaction. These results suggest that HRV is a direct index of cognitive rather than emotional regulation.  相似文献   
224.
Five hundred and thirty-one nurses completed a questionnaire assessing knowledge about the flu and flu vaccination, professional group identification, perception of the flu vaccination as a professional duty, previous year's vaccination status, intention to receive vaccination in the following year, and the extent to which motivation to accept vaccination is primarily for self-protection or for patient protection. Results showed that knowledge about the flu and flu vaccination constitutes a major reason for rejecting immunisation. Group identification also constitutes an independent predictor of vaccination. Furthermore, the effect of identification on willingness to receive the vaccination was partially mediated by perceived professional responsibility: the more nurses identified with their group, the more they perceived vaccination as a professional duty and, as a consequence, the more likely that they (a) had been vaccinated the previous year, (b) intended to be vaccinated in the following year, and (c) were motivated to be vaccinated for patient protection (but not for self-protection).  相似文献   
225.
Gaze following allows individuals to detect the locus of attention of both conspecifics and other species. However, little is known about how this ability develops. We explored the emergence of bobwhite quail hatchlings’ ability to track human gaze by assessing their avoidance behavior in an open arena under five testing conditions: (1) a Direct Gaze condition, in which an experimenter looking down was positioned above one of two approach areas; (2) a Gaze Follow condition in which an experimenter, positioned equidistant between two approach areas, directed his/her gaze towards one of the areas; (3) a Masked Gaze Follow condition, in which the experimenter wore a mask during the Gaze Follow test; (4) a Deprived Face Experience condition, in which hatchlings were deprived of experience with human faces prior to the Gaze Follow test; and (5) a Control condition in which no experimenter was present during testing. Results revealed that hatchlings from the Direct Gaze condition preferred the non-gazed approach area at all ages tested. Hatchlings from the Gaze Follow condition preferred the non-gazed approach area at 48 and 72 h, but not at 24 h of age. In contrast, hatchlings from the Masked Gaze Follow, Deprived Face and Control conditions did not prefer either approach area at any age tested. These results indicate that experience with human faces plays a key role in the rapid emergence of gaze following behavior in bobwhite quail hatchlings.  相似文献   
226.
选取36名大学生,运用眼动技术,探讨不同结构类型文章在重复阅读时主题转换效应的变化特点。被试阅读的材料有两类:一是段落内部各个句子之间为平行关系(平行材料);一是每段第一个句子为该段落主题句(总分材料)。结果发现,两类材料在第一遍阅读过程中均出现了显著的主题转换效应,但在重复阅读时,主题转换效应消失,说明读者在第一遍阅读时已构建了文章的主题结构表征,并以此来指导后面的阅读。该结果支持共同策略假设理论,说明无论文章中是否存在标记,读者在阅读时都会构建一定完善的主题结构表征。  相似文献   
227.
A conditioned taste aversion experiment tested context-switch effects on retrieval of conditioned stimulus (CS)-unconditioned stimulus (US) acquisition performance in rats. A context switch impaired performance when the target flavour was trained in a context where a different flavour underwent extinction. Conditioned taste aversion in the absence of previous extinction of the alternate flavour was not context dependent. It is suggested that the ambiguity in the meaning of the extinguished cue leads animals to pay attention to the context, so that the information learned in that context becomes context dependent.  相似文献   
228.
The present experiments tested whether endogenous and exogenous cues produce separate effects on target processing. In Experiment 1, participants discriminated whether an arrow presented left or right of fixation pointed to the left or right. For 1 group, the arrow was preceded by a peripheral noninformative cue. For the other group, the arrow was preceded by a central, symbolic, informative cue. The 2 types of cues modulated the spatial Stroop effect in opposite ways, with endogenous cues producing larger spatial Stroop effects for valid trials and exogenous cues producing smaller spatial Stroop effects for valid trials. In Experiments 2A and 2B, the influence of peripheral noninformative and peripheral informative cues on the spatial Stroop effect was directly compared. The spatial Stroop effect was smaller for valid than for invalid trials for both types of cues. These results point to a distinction between the influence of central and peripheral attentional cues on performance and are not consistent with a unitary view of endogenous and exogenous attention.  相似文献   
229.
多媒体环境下图文的具体程度对学习效果的影响   总被引:1,自引:0,他引:1  
让70名小学生在多媒体环境中学习概念材料与原理材料,以探讨文本和图画材料的具体程度对学习迁移效果的影响。结果表明,在概念材料上,文本与图画的具体性程度之间存在显著的交互作用,即在具体图水平上,具体文的迁移成绩显著高于抽象文;在抽象图水平上,具体文的迁移成绩低于抽象文,但没有达到显著性水平。在原理材料上,文本与图画的具体性程度之间也存在显著的交互作用,但交互作用的方式与概念材料相反,即在具体图水平上,具体文的迁移成绩显著低于抽象文;在抽象图水平上,具体文的迁移成绩高于抽象文,但没有达到显著水平。  相似文献   
230.
研究为探索常驻高海拔地区军人心理健康水平如何随社会年代变迁而改变,运用了横断历史元分析的方法,对1993年至2013年38篇采用90项症状自评量表(SCL-90)的文献调查数据进行分析,考察了11454名常驻高海拔地区军人在该量表上9个因子得分随年代变化的趋势.结果发现:(1)SCL-90的7个因子均值与年代负相关,且不受期刊类型等的影响.20年来,7个因子下降了5%~15%不等.其中,强迫变化最大,抑郁、焦虑、人际敏感、偏执和精神病性均变化明显.这说明,常驻高海拔地区军人心理健康虽有所波动但整体水平逐步提升,变化幅度大致属于中等程度.(2)当年军费占GDP比值、居民消费水平指数与SCL-90部分因子均值负相关显著;5年前的居民消费水平指数与7个因子显著负相关.这说明,国防建设的经济投入和居民消费水平可能是影响常驻高海拔地区军人心理健康水平的重要因素.  相似文献   
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