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171.
Although quantitative analysis (in which behavior principles are defined in terms of equations) has become common in basic behavior analysis, translational efforts often examine everyday events through the lens of narrative versions of laboratory-derived principles. This approach to translation, although useful, is incomplete because equations may convey concepts that are difficult to capture in words. To support this point, we provide a nontechnical introduction to selected aspects of quantitative analysis; consider some issues that translational investigators (and, potentially, practitioners) confront when attempting to translate from quantitative models; and discuss examples of relevant translational studies. We conclude that, where behavior-science translation is concerned, the quantitative features of quantitative models cannot be ignored without sacrificing conceptual precision, scientific and practical insights, and the capacity of the basic and applied wings of behavior analysis to communicate effectively.  相似文献   
172.
Substantial evidence indicates that information is distorted during decision making, but very few studies have assessed the distortion of probability and outcome information in risky decisions. In two studies involving six binary decisions (e.g., banning blood donations from people who have visited England, because of “mad cow disease”), student and nonstudent participants distorted their evaluations of probability and outcome information in the direction of their preferred decision alternative and used these biased evaluations to update their preferences. Participants also evaluated the utilities of possible outcomes more positively when the outcomes could follow only from the preferred alternative and more negatively when they could follow only from the competing alternative. Such circular reasoning is antithetical to the normative consequentialist principles underlying decision analysis. Presenting numerical information as precise values or as ranges of values did not significantly affect information distortion, apparently because the manipulation did not affect perceived ambiguity as intended.  相似文献   
173.
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   
174.
为了探讨脑胶质母细胞瘤术后放疗对肝细胞生长因子受体表达规律的影响,对25例胶质母细胞瘤患者进行研究。结果显示肝细胞生长因子受体在复发前接受放疗与未接受放疗的患者中,复发后肝细胞生长因子受体表达及复发时间差异明显(P〈0.05)。因此放疗能对肝细胞生长因子受体在胶质母细胞瘤的表达产生影响,进而影响到其复发时间。  相似文献   
175.
血管内皮生长因子(vascular endothelial growth factor,VEGF)是一高度特异作用于内皮细胞的糖蛋白,是目前发现的最重要的肿瘤血管生长因子之一。结直肠癌的生长、侵袭和转移与血管内皮生长因子有密切的关系,VEGF在结直肠癌治疗中的作用日益突出。本文就VEGF的功能、在结直肠癌中的表达和治疗的作用作一综述。  相似文献   
176.
血管内皮生长因子(vascular endothelial growth factor,VEGF)是一高度特异作用于内皮细胞的糖蛋白,是目前发现的最重要的肿瘤血管生长因子之一.结直肠癌的生长、侵袭和转移与血管内皮生长因子有密切的关系,VEGF在结直肠癌治疗中的作用日益突出.本文就VEGF的功能、在结直肠癌中的表达和治疗的作用作一综述.  相似文献   
177.

Objective

Negative affect has been purported to play an important role in the etiology and maintenance of bulimic behaviors. The objective of this study was to identify daily mood patterns in the natural environment exhibited by individuals with bulimia nervosa and to examine the relationship between these patterns and bulimic behaviors.

Method

One hundred thirty-three women aged 18-55 meeting DSM-IV criteria for bulimia nervosa were recruited through clinical referrals and community advertisements. Ecological momentary assessment was used to collect multiple ratings of negative affect, binge eating and purging each day for a two-week period using palmtop computers. Latent growth mixture modeling was used to identify daily mood patterns.

Results

Nine distinct daily mood patterns were identified. The highest rates of binge eating and purging episodes occurred on days characterized by stable high negative affect or increasing negative affect over the course of the day.

Conclusions

These findings support the conclusion that negative mood states are intimately tied to bulimic behaviors and may in fact precipitate such behavior.  相似文献   
178.
We determined whether effects of neighborhood socioeconomic disadvantage on trajectories of aggression were moderated or mediated by neighborhood social organization and examined sex differences in neighborhood effects for rural adolescents. We used five waves of survey data collected over 2.5 years linked with neighborhood data from interviews with parents and the US Census. The sample (N = 5,118) was 50.1% female, 52.0% white and 38.3% African–American; average age at baseline was 13.1 years. Multilevel growth curve models for both girls and boys showed no significant interactions between neighborhood socioeconomic disadvantage and indicators of social organization. Neither sample showed evidence of mediated effects. In main effects models, neighborhood disadvantage was associated with the average aggression trajectory for girls. For boys, the effects of neighborhood socioeconomic disadvantage and social disorganization appeared to be confounded with each other. Neighborhood disadvantage is detrimental for rural girls regardless of the level of social organization.  相似文献   
179.
Recent findings have provided much insight into the mechanisms underlying long-term memory formation, and it is now known that long-term memory depends on the activation of a molecular cascade that culminates with structural changes in the brain. However, little is known about the signals that give rise to or regulate these structural changes. In this article we propose that fibroblast growth factor-2 (FGF2), a mitogen for several cell types, may be one of the molecular signals critically involved in the structural changes underlying long-term memory. If FGF2 is part of the signalling cascade involved in long-term memory, then increasing the activation of FGF2 should facilitate memory. In Experiments 1 and 2, we demonstrated that systemic injection of FGF2 (20 ng/g of body weight) facilitated memory for contextual fear in 16, 19, and 22 day old male Sprague Dawley rats. Experiment 3 demonstrated that the observed facilitation of memory was not due to FGF2 increasing rats’ sensitivity to footshock. These results implicate FGF2 as a possible molecular signal in long-term memory, and further, illustrate a novel means of enhancing memory.  相似文献   
180.
Research has found that neighborhood structural characteristics can influence residents' mental health. Few studies, however, have explored the proximal reasons behind such influences. This study investigates how different types of communities, in terms of environmental stressors (social and physical disorder and fear of crime) and social resources (informal ties and formal organizational participation), affect well-being, depression, and anxiety in adult residents. Data are from a survey of 412 residents nested in 50 street blocks. Block stressors and resources were cluster analyzed to identify six block types. After controlling for several individual- and block-level characteristics, results from multilevel models suggest that in communities facing relatively few stressors, higher levels of formal participation are associated with better mental health. Because high levels of formal participation were not found in communities with higher levels of stressors, the impact of participation in such contexts could not be examined. However, results suggest that in communities where stressors are more common, isolation from neighbors may have a protective effect on mental health.  相似文献   
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