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101.
Fragile X mental retardation protein (FMRP), which is absent in fragile X syndrome, is synthesized in vitro in response to neurotransmitter activation. Humans and mice lacking FMRP exhibit abnormal dendritic spine development, suggesting that this protein plays an important role in synaptic plasticity. Previously, our laboratory demonstrated increased FMRP immunoreactivity in visual cortex of rats exposed to complex environments (EC) and in motor cortex of rats trained on motor-skill tasks compared with animals reared individually in standard laboratory housing (IC). Here, we use immunohistochemistry to extend those findings by investigating FMRP levels in visual cortex and hippocampal dentate gyrus of animals exposed to EC or IC. Rats exposed to EC for 20 days exhibited increased FMRP immunoreactivity in visual cortex compared with animals housed in standard laboratory caging. In the dentate gyrus, animals exposed to EC for 20 days had higher FMRP levels than animals exposed to EC for 5 or 10 days. In light of possible antibody crossreactivity with closely related proteins FXR1P and FXR2P, FMRP immunoreactivity in the posterior-dorsal one-third of cerebral cortex was also examined by Western blotting following 20 days of EC exposure. FMRP levels were greater in EC animals, whereas levels of FXR1P and FXR2P were unaffected by experience. These results provide further evidence for behaviorally induced alteration of FMRP expression in contrast to its homologues, extend previous findings suggesting regulation of its expression by synaptic activity, and support the theories associating FMRP expression with alteration of synaptic structure both in development and later in the life-cycle.  相似文献   
102.
The question "Should organizations be concerned with the eldercare responsibilities of their employees?" was addressed from several perspectives: (1) prevalence of need, (2) the relationships among eldercare responsibilities, satisfaction with eldercare arrangements, and workplace attitudes and outcomes, and (3) support for organizational eldercare programs. Our sample was predominately female and we defined eldercare responsibilities broadly; however, only 5 of 885 employees reported eldercare responsibilities. The majority relied on family arrangements and reported dissatisfaction with these arrangements. Dissatisfaction was related to interruptions at work, leaving early, and intent to quit. Eldercare-givers did not differ from other groups on job satisfaction and organizational commitment, but were absent from work significantly more often. There was strong employee support for employer-sponsored eldercare programs.  相似文献   
103.
The present study used general growth mixture modeling to identify pathways of antisocial behavior development within an epidemiological sample of urban, primarily African American boys. Teacher-rated aggression, measured longitudinally from 1st to 7th grade, was used to define growth trajectories. Three high-risk trajectories (chronic high, moderate, and increasing aggression) and one low-risk trajectory (stable low aggression) were found. Boys with chronic high and increasing trajectories were at increased risk for conduct disorder, juvenile and adult arrest, and antisocial personality disorder. Concentration problems were highest among boys with a chronic high trajectory and also differentiated boys with increasing aggression from boys with stable low aggression. Peer rejection was highest among boys with chronic high aggression. Interventions with boys with distinct patterns of aggression are discussed.  相似文献   
104.
Timed picture naming was compared in seven languages that vary along dimensions known to affect lexical access. Analyses over items focused on factors that determine cross-language universals and cross-language disparities. With regard to universals, number of alternative names had large effects on reaction time within and across languages after target-name agreement was controlled, suggesting inhibitory effects from lexical competitors. For all the languages, word frequency and goodness of depiction had large effects, but objective picture complexity did not. Effects of word structure variables (length, syllable structure, compounding, and initial frication) varied markedly over languages. Strong cross-language correlations were found in naming latencies, frequency, and length. Other-language frequency effects were observed (e.g., Chinese frequencies predicting Spanish reaction times) even after within-language effects were controlled (e.g., Spanish frequencies predicting Spanish reaction times). These surprising cross-language correlations challenge widely held assumptions about the lexical locus of length and frequency effects, suggesting instead that they may (at least in part) reflect familiarity and accessibility at a conceptual level that is shared over languages.  相似文献   
105.
In most countries, adolescents' access to abortion is limited by restrictions on legal abortion. Abortion is legal in the United States, but many states require parental consent or notification. Legislation mandating parental consent has been justified by several assumptions, including high risk of psychological harm from abortion, adolescents' inability to make an adequately informed decision, and benefits of parental involvement. Empirical data raise questions about the first 2 assumptions: Studies suggest a relatively low risk associated with abortion, and adolescents seeking abortion appear to make an informed choice. Less is known about effects of parental involvement. The authors review available research and discuss policy debates over parental consent in the United States and the international context.  相似文献   
106.
The authors trained 3 adult male rhesus macaques (Macaca mulatta) to categorize pairs of unknown conspecifics presented in a video according to the dominance status of the videotaped monkeys. The subjects were trained to choose the dominant monkey for a category of films (e.g., films showing 1 monkey chasing another); then, new films were presented involving different conspecifics, and the monkeys' first responses to this new category of behavior (e.g., monkeys fighting) were taken as evidence of transfer. Two subjects were able to generalize categorical judgments of dominance to new films involving new behaviors. These findings seem to indicate that monkeys can use abstract social concepts and are aware of the social relationships within their group.  相似文献   
107.
108.
Conducting research on adolescents raises a number of ethical issues not often confronted in research on younger children. In part, these differences are due to the fact that although assent is usually not an issue, given cognitive and social competencies, the life situations and behavior of youth make it more difficult to balance rights and privacy of the adolescents. In this article, the three ethical principles of beneficence, justice, and respect for persons are discussed in terms of their application to the study of adolescents. Then, seven vignettes are presented to illustrate how these principles apply to real-life situations. How to balance the rights of adolescents and their parents is discussed, using adolescent girls and their parents for illustrative purposes.  相似文献   
109.
110.
At its origins, analytic philosophy is an interest in language, science, logic, analysis, and a systematic rather than a historical approach to philosophical problems. Early analytic philosophers were famous for making clear conceptual distinctions and for couching them in comprehensible and lucid sentences. It is argued that this situation is changing, that analytic philosophy is turning into its mirror image and is thereby becoming more like the kind of philosophy that it used to oppose.  相似文献   
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