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81.
Attentional biases and the right-ear effect in dichotic listening   总被引:2,自引:0,他引:2  
Most dichotic listening experiments permit subjects to deploy attention in any way they choose. We argue that this adds uncontrolled variance to the observed right-ear advantage. In the first experiment, more robust laterality effects were obtained in an identification task with focused than with divided attention. Such differences were not found in the second experiment, when a detection procedure was used. Virtually all the laterality effect observed in the second study could be attributed to subjects who were biased attenders, in the sense that they exhibited more intrusions from the right ear to the left than vice versa. However, rather than indicating that laterality effects are simply attentional bias, this effect can be attributed to an asymmetry of perceptual discrimination.  相似文献   
82.
The current literature on sex differences in values/preferences related to work appears polarized around two apparently contradictory sets of findings and conclusions. One set of studies fails to detect sex differences. The other set of studies indicates that males are more concerned about money, independence, security, and career goals, while females appear more concerned about people and environmental issues at work. Following W. D. Siegfried, I. MacFarlane, D. B. Graham, N. A. Moore, and P. L. Young (Journal of Vocational Behavior, 1981, 18, 30–42) it is suggested that level of analysis may be a crucial factor accounting for much of the prevailing confusion in the literature. This study investigated sex differences in values/preferences related to work at various levels of generality. A sample of 1081 senior high school students was administered the Work Aspect Preference Scale (WAPS). Complete-link cluster analyses were performed for males and females separately. Comparison of the two dendrograms reveals the substantial similarity of the preference patterns of males and females. However, the basic difference in the patterns focused on the Altruism and Physical Activity subscales. Females appeared more likely to associate helping others with personal achievement whereas males tended to see helping people in terms of controlling and organizing them. Females also linked physical activity with helping others and self-development whereas males tended to associate physical activity with extrinsic rewards of work. It is concluded that the use of cluster analysis techniques may provide the best procedure to effect an adequate reconciliation of the conflicting results to be found in the current literature.  相似文献   
83.
研究甲状腺癌组织中趋化因子4受体(CXCR4)和趋化因子7受体(CXCR7)的表达情况及临床病理意义。应用免疫组织化学PV-6000法及Westernblot法检测CXCR4与CXCR7在甲状腺癌中的表达。二者在甲状腺癌与甲状腺良性疾病组织的差异均具有统计学意义(P〈0.05),在甲状腺癌中表达仅与淋巴结转移有关(P〈0.05),CXCR4与CXCR7之间呈正相关。Westernblot结果提示二者在甲状腺癌中的表达率高于癌旁及甲状腺腺瘤。CXCR4和CXCR7的表达水平与淋巴结转移相关,可作为甲状腺癌预后的判断指标。  相似文献   
84.
为了探讨肝激酶B1(LKB1)蛋白在食管鳞癌组织中的表达水平及其与食管鳞癌临床特征及生存期的关系,应用免疫组化方法检测120例食管鳞癌患者组织中LKB1蛋白表达情况并对诸多临床特征进行相关性分析研究,发现LKB1蛋白在食管癌旁正常组织的阳性表达率高于癌组织;LKB1蛋白表达与患者年龄、性别、肿瘤部位、病变长度及浸润深度无关而与分化程度、淋巴结转移及临床分期(TNM)相关,且LKB1蛋白阴性组预后较阳性组差.可见LKB1视为抑癌基因影响食管鳞癌的预后,可能成为食管鳞癌新型的临床预后指标之一.  相似文献   
85.
词切分的韵律学线索   总被引:1,自引:0,他引:1  
杨玉芳 《心理学报》1992,25(4):59-65
本文是关于汉语普通话词切分的一个实验报告。用无意文重复句和合成句作语音材料,探讨音节时长分布、基频曲线、音节强度以及共振峰等韵律学线索在词切分中的作用。得到的主要结果是,在排除语义和音段层面信息的条件下,听者能够根据句子的韵律学特征进行句子结构的判断和词的切分;在对切分有效的韵律学线索中,最重要的是音节的时长分布模式,其次是基频曲线,音节的强度和共振峰变化对切分没有贡献。  相似文献   
86.
Residual fluctuations produced in typical experimental methodologies are examined as correlated noises. The effective range of the correlations was assessed by determining whether the decay over look-back time is better described as a power law or exponential. Both of these decay laws contain free parameters and it is argued that it is not possible to distinguish their models on the basis of simple measures of goodness-of-fit. Global analyses that evaluate models on the basis of how well they generalize are conducted. The models are examined in terms of three constructs that all bear on generalization: cross-validity, flexibility, and representativeness. Quantitative assessment of a large ensemble of data suggests that the correlations decay over time as a power law. The conclusion is that human residual fluctuation is a correlated fractal.  相似文献   
87.
高危型别人乳头瘤病毒(HPV)感染在宫颈癌发生发展中具有重要作用。由于HPV L1蛋白结构特征及其精确的抗原特性,在粘附宿主细胞、识别病毒受体、协助病毒DNA的入胞转运中均发挥重要作用。检测患者宫颈损伤组织中L1蛋白的表达将有助于对患者是否具有传染性进行评估。本文将深刻思考HPV L1功能及其在感染机体并引发癌变的机制,以期更好的解读宫颈癌发病原理并最终应用于,强床治疗。  相似文献   
88.
为了探讨前列腺素E1的脂微球载体靶向制剂(Lipo PGE1)对肾移植术后移植肾功能恢复和血流动力学的影响,80例肾移植受者在术后被随机分成两组:PGE1组和对照组。PGE1组从手术当天起至术后第14天每天给予静脉注射Lipo PGE1 20μg。比较两组术后尿量、血肌酐、彩色多普勒超声下移植肾收缩期最大血流速度(PSV)和血流阻力指数(RI)以及两组肾功能恢复延迟(DGF)的发生率。应用Lipo PGE1的患者术后尿量明显高于对照组(P〈0.05),而血肌酐、PSV、RI和肾功能恢复延迟发生率则明显低于对照组(P〈0.05)。因此,前列腺素E1有利于肾移植术后移植肾功能的恢复,对肾移植术后早期肾动脉血流动力学有促进作用。  相似文献   
89.
Entorhinal neurons receive extensive intracortical projections, and form the primary input to the hippocampus via the perforant pathway. The glutamatergic cells of origin for the perforant pathway are distinguished by their expression of reelin, a glycoprotein involved in learning and synaptic plasticity. The functional significance of reelin signaling within the entorhinal cortex, however, remains unexplored. To determine whether interrupting entorhinal reelin signaling might have consequences for learning and memory, we administered recombinant receptor-associated protein (RAP) into the lateral entorhinal cortex (LEC) of young Long-Evans rats. RAP prevents reelin from binding to its receptors, and we verified the knockdown of reelin signaling by quantifying the phosphorylation state of reelin’s intracellular signaling target, disabled-1 (DAB1). Effective knockdown of reelin signaling was associated with impaired performance in the hippocampus-dependent version of the water maze. Moreover, inhibition of reelin signaling induced a localized loss of synaptic marker expression in the LEC. These observations support a role for entorhinal reelin signaling in spatial learning, and suggest that an intact reelin signaling pathway is essential for synaptic integrity in the adult entorhinal cortex.  相似文献   
90.
A multidisciplinary group of genetic and other professionals discuss a complex case of familial conflict over access to genetic information. One twin wishes to know the results of her deceased mother's tests for BRCA1 mutations; a second twin objects to researchers making this information available. As the case discussion unfolds, the apparent facts of this case are called into question and the lines of ethical certainty become less clear.  相似文献   
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