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801.
Lambert SF Brown TL Phillips CM Ialongo NS 《American journal of community psychology》2004,34(3-4):205-218
Although the neighborhood microsystem is recognized as an important domain for adolescent development, relative to the family and peer contexts, neighborhood factors have been understudied in relation to adolescent substance abuse. In addition, recent research suggests that risk factors for adolescent substance use may differ for African Americans when compared to Caucasian youth. This study investigated the association between perceived neighborhood disorganization and later substance use, as well as possible mediators of that association, among a community sample of urban African American adolescents. Perceptions of neighborhood disorganization (i.e., violence/safety and drug activity) in grade 7 were associated with increased tobacco, alcohol, and marijuana use in grade 9. For females, this association was mediated by attitudes about drug use and perceptions of drug harmfulness. Findings highlight the importance of neighborhood contextual variables for African American substance use. Implications and directions for future research are presented. 相似文献
802.
Vrhovac B 《Science and engineering ethics》2004,10(1):81-93
The Helsinki Declaration is the ‘gold standard’ — a directive, not a law, on how to conduct controlled studies in humans in
conformity with ethical principles. In spite of many discussions about their unsuitability some articles have remained unchanged
in the most recent (sixth) revision of the Declaration. The demand to use “the best treatment” excludes use of placebo in
the control group and presents an obstacle to the scientific evaluation of a number of drugs and treatments in general. The
use of placebo is justified whenever its use does not cause irreversible damage or considerable suffering to the well informed
patient. It must be, is, and will be used in the controlled clinical trials of treatments of a great number of diseases especially
those which have a tendency to spontaneous improvement, even healing, or have a pronounced psychological component
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
803.
This research examined exchange and value attribution in tufted capuchin monkeys (Cebus apella). We presented subjects with opportunities to obtain various foods and a tool from an experimenter in exchange for the foods or tool in the subjects' possession. The times elapsed before the first chow biscuits were expelled and/or an exchange took place were recorded as the dependent measures. Laboratory chow biscuits, grapes, apples, and a metal bolt (a tool used to probe for syrup) were used as experimental stimuli. The subjects demonstrated the ability to recognize that exchanges could occur when an experimenter was present with a desirable food. Results indicate that subjects exhibited significant variation in their willingness to barter based upon the types of foods that were both in their possession and presented by the experimenter. Subjects more readily traded chow biscuits for fruit, and more readily traded apples for grapes than grapes for apples. During the exchange of tools and food, the subjects preferred the following in descending order when the probing apparatus was baited with sweet syrup: grapes, metal bolts, and chow biscuits. However when the apparatus was not baited, the values changed to the following in descending order: grapes, chow, and metal bolts. These results indicate that tufted capuchins recognize opportunities to exchange and engage in a simple barter system whereby low-valued foods are readily traded for more highly valued food. Furthermore, these capuchins demonstrate that their value for a tool changes depending upon its utility. 相似文献
804.
Zvolensky MJ Bonn-Miller MO Bernstein A McLeish AC Feldner MT Leen-Feldner EW 《Behaviour research and therapy》2006,44(7):907-924
The present investigation evaluated whether anxiety sensitivity interacted with marijuana use in relation to the prediction of panic-relevant variables among young adult tobacco smokers (n=265). Approximately 73% of the sample was composed of current marijuana smokers, with 78.5% of this sub-sample using marijuana more than once per week. As expected, after covarying cigarettes per day, alcohol use, and negative affectivity, the interaction between marijuana use and anxiety sensitivity predicted anxiety symptoms and agoraphobic cognitions. Partially consistent with prediction, the interaction between frequency of marijuana use and anxiety sensitivity predicted only anxiety symptoms. These results are discussed in relation to better understanding the potential role of regular marijuana use and anxiety sensitivity for panic-relevant emotional vulnerability among regular tobacco smokers. 相似文献
805.
Dissociations between implicit and explicit memory in children: the role of strategic processing and the knowledge base 总被引:4,自引:0,他引:4
A review of the literature shows that explicit memory develops substantially from three years of age to adulthood, while implicit memory remains stable across this age range. Previously, this developmental dissociation has been attributed to different memory systems, or to confounds with perceptual vs. conceptual processing. Prompted by an alternative developmental framework, the experiments reported here provide evidence against both interpretations. Instead, it will be argued that (a) the implicit-explicit developmental dissociation reflects differences in strategic processing (strategy use and metamemory) across childhood and (b) that implicit memory can show development if a child's knowledge base in the tested domain is developing with age. 相似文献
806.
Risk factors, such as emotional distress and peer substance involvement, are often tested as competing influences on adolescent substance use. However, the current study examined how affect (both positive and negative) and peers (both in terms of relationship quality and substance involvement) are interactive influences on adolescent substance use. A sample of 398 high school juniors and seniors completed surveys assessing each of these domains. Results of hierarchical regression analyses showed strong associations between an adolescent's and his or her best friend's substance use. Complex interactions supported the study hypothesis in that relations between affect and adolescent substance use were context dependent, with some peer contexts enhancing risk for substance use and others dampening this risk. Implications of these findings for interventions and preventions concerning adolescent substance use are discussed. 相似文献
807.
This article explores the maternal role in the acquisition of tool-use behaviours by infant chimpanzees (Pan troglodytes). A honey-fishing task, simulating ant/termite fishing found in the wild, was introduced to three dyads of experienced mother and naïve infant chimpanzees. Four fishing sites and eight sets of 20 objects to be used as tools, not all appropriate, were available. Two of the mothers constantly performed the task, using primarily two kinds of tools; the three infants observed them. The infants, regardless of the amount of time spent observing, successfully performed the task around the age of 20–22 months, which is earlier than has been recorded in the wild. Two of the infants used the same types of tools that the adults predominantly used, suggesting that tool selectivity is transmitted. The results also show that adults are tolerant of infants, even if unrelated; infants were sometimes permitted to lick the tools, or were given the tools, usually without honey, as well as permitted to observe the adult performances closely.Electronic Supplementary Material Supplementary material is available in the online version of this article at 相似文献
808.
Stereotypes and biological theories suggest that psychological gender differences found in predominantly heterosexual samples are smaller or reversed among gay men and lesbians. Computerized text analysis that compares peoples language style on a wide range of dimensions from pronoun use to body references offers a multivariate personality marker to test such assumptions. Analysis of over 1,500 internet personal advertisements placed by heterosexual men, heterosexual women, gay men, and lesbians found little evidence that orientation alters the impact of gender on linguistic behaviors. Previously reported gender differences were replicated in the gay as well as the heterosexual advertisements studied. Main effects of sexual orientation indicated that gay people of both sexes apparently felt less need to differentiate themselves from potential mates than did heterosexual people. Virtually no crossover sexual orientation by sex interactions emerged indicating that several popular models of sexual orientation are not supported on a linguistic level. 相似文献
809.
Tiffanie?SimEmail author Lisa?Jordan-Green Jade?Wolfman 《Journal of religion and health》2005,44(3):291-301
The study utilized qualitative methods to study protective factors among middle school students who were at risk for substance
use. Three focus groups (consisting of 6–7 parents each) were conducted to learn more about parent’s perceptions of protective
factors within the neighborhood, school, family, and the individual. In terms of spirituality, parents stressed the importance
of church involvement in preventing high-risk behaviors. These findings will be highlighted to provide information that may
serve as a basis for further examining church involvement and spirituality as protective factors in adolescent substance use. 相似文献
810.
Tikk A 《Science and engineering ethics》2002,8(3):317-318
An area where conflicts of interest can take place in Estonia is in the conduct of clinical trials. The paper lists the main
areas where such conflicts of interest can occur. The author also briefly discusses Estonia’s current position with regard
to regulating genetic information and the commencement of the Estonian Genome Project.
An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance
in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002. 相似文献