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751.
The aim of the current study was to determine whether age and body satisfaction predict dietary adherence in adolescents with Inflammatory Bowel Disease (IBD), and whether older females are less adherent than younger males and females. Forty-four participants aged 10–21 with IBD were recruited. Participants provided informed consent and demographics. Body satisfaction was measured by a questionnaire and a task in which participants selected their current and ideal body image out of silhouettes depicting bodies ranging from underweight to obese. Adherence was measured by marking a 100 mm visual analog scale, the 1-week completion of a dietary log, and a questionnaire evaluating coping strategies used for overcoming obstacles to dietary adherence. Age was related to dietary adherence, with younger children being more likely to adhere. Participants more satisfied with their body reported better dietary adherence. Findings remained consistent across multiple measures of body satisfaction and adherence. Healthcare providers and parents should be informed of these findings in order to improve adherence.  相似文献   
752.
Previously, we found that in the lateral amygdala (LA) of the mouse, WIN55,212-2 decreases both glutamatergic and GABAergic synaptic transmission via activation of the cannabinoid receptor type 1 (CB1), yet produces an overall reduction of neuronal excitability. This suggests that the effects on excitatory transmission override those on inhibitory transmission. Here we show that CB1 activation by WIN55,212-2 and Delta(9)-THC inhibits long-term depression (LTD) of basal synaptic transmission in the LA, induced by low-frequency stimulation (LFS; 900 pulses/1 Hz). The CB1 agonist WIN55,212-2 blocked LTD via G(i/o) proteins, activation of inwardly rectifying K+ channels (K(ir)s), inhibition of the adenylate cyclase-protein kinase A (PKA) pathway, and PKA-dependent inhibition of voltage-gated N-type Ca2+ channels (N-type VGCCs). Interestingly, WIN55,212-2 effects on LTD were abolished in CB1 knock-out mice (CB1-KO), and in conditional mutants lacking CB1 expression only in GABAergic interneurons, but were still present in mutants lacking CB1 in principal forebrain neurons. LTD induction per se was unaffected by the CB1 antagonist SR141716A and was normally expressed in CB1-KO as well as in both conditional CB1 mutants. Our data demonstrate that activation of CB1 specifically located on GABAergic interneurons inhibits LTD in the LA. These findings suggest that CB1 expressed on either glutamatergic or GABAergic neurons play a differential role in the control of synaptic transmission and plasticity.  相似文献   
753.
An automated training system was used to compare the behavior of knockout (KO) mice lacking the fragile X mental retardation protein with that of wild-type (WT) mice (C57Bl/6 strain) in the acquisition and retention of olfactory discriminations. KO and WT mice did not differ in the acquisition of a four-stage nose poke shaping procedure. In two separate experiments, mutant mice required substantially more training to acquire a series of novel olfactory discrimination problems than did control mice. The KO mice required significantly more sessions to reach criterion performance, made significantly more errors during training, and more often failed to acquire discriminations. Both KO and WT mice showed similar error patterns when learning novel discriminations and both groups showed evidence of more rapid learning of later discriminations in the problem series. Both groups showed significant long-term memory two or four weeks after training but WT and KO mice did not differ in this regard. A group of well-trained mice were given training on novel odors in sessions limited to 20–80 trials. Memory of these problems at two day delays did not differ between WT and KO mice. Tests using ethyl acetate demonstrated that WT and KO mice had similar odor detection thresholds.  相似文献   
754.
Social scientific investigation into the religiospiritual characteristics of American Indians rarely includes analysis of quantitative data. After reviewing information from ethnographic and autobiographical sources, we present analyses of data from a large, population-based sample of two tribes (n = 3,084). We examine salience of belief in three traditions: aboriginal, Christian, and Native American Church. We then investigate patterns in sociodemographic subgroups, determining the significant correlates of salience with other variables controlled. Finally, we examine frequency with which respondents assign high salience to only one tradition (exclusivity) or multiple traditions (nonexclusivity), again investigating subgroup variations. This first detailed, statistical portrait of American Indian religious and spiritual lives links work on tribal ethnic identity to theoretical work on America's "religious marketplace." Results may also inform social/behavioral interventions that incorporate religiospiritual elements.  相似文献   
755.
Common Representations of Abstract Quantities   总被引:2,自引:0,他引:2  
ABSTRACT— Representations of abstract quantities such as time and number are essential for survival. A number of studies have revealed that both humans and nonhuman animals are able to nonverbally estimate time and number; striking similarities in the behavioral data suggest a common magnitude-representation system shared across species. It is unclear, however, whether these representations provide animals with a true concept of time and number, as posited by Gallistel and Gelman (2000) . In this article, we review the prominent cognitive and neurobiological models of timing and counting and explore the current evidence suggesting that nonhuman animals represent these quantities in a modality-independent (i.e., abstract) and ordered manner. Avenues for future research in the area of temporal and mathematical cognition are also discussed.  相似文献   
756.
The current study involved a comprehensive comparative examination of overt and relational aggression and victimization across multiple perspectives in the school setting (peers, teachers, observers in the lunchroom, self-report). Patterns of results involving sociometic status, ethnicity and gender were explored among 4th graders, with particular emphasis on girls. Controversial and rejected children were perceived as higher on both forms of aggression than other status groups, but only rejected children were reported as victims. Both European American and African American girls showed a greater tendency toward relational aggression and victimization than overt aggression or victimization. Results indicated negative outcomes associated with both relational and overt victimization and especially overt aggression for the target girl sample. Poorer adjustment and a socially unskillful behavioral profile were found to be associated with these three behaviors. However, relational aggression did not evidence a similar negative relation to adjustment nor was it related to many of the behaviors examined in the current study. Implications of these results are discussed.  相似文献   
757.
Prospective links among reactive aggression, proactive aggression, and victimization by peers were investigated in a longitudinal sample of 238 preadolescents (aged 10-13 years, 52% girls). No predictive links were found between victimization and either type of aggression among girls. Among boys, reactive aggression predicted higher future levels of victimization but was not itself affected by prior victimization. In contrast, boys' proactive aggression predicted lower levels of future victimization and was itself reduced by their prior victimization. Finally, reactive aggression predicted later proactive aggression for both boys and girls. These results are explained in terms of the different reactions that others have to proactive and reactive aggression, the different functions they serve, and to the different types of aggression that are common for boys and girls.  相似文献   
758.
Personality in domestic cats   总被引:1,自引:0,他引:1  
Personality ratings of 196 cats were made by their owners using a 5-point Likert scale anchored by 1: not at all and 5: a great deal with 12 items: timid, friendly, curious, sociable, obedient, clever, protective, active, independent, aggressive, bad-tempered, and emotional. A principal components analysis with varimax rotation identified three intepretable components. Component I had high loadings by active, clever, curious, and sociable. Component II had high loadings by emotional, friendly, and protective, Component III by aggressive and bad-tempered, and Component IV by timid. Sex was not associated with any component, but age showed a weak negative correlation with Component I. Older animals were rated less social and curious than younger animals.  相似文献   
759.
Although there is a large and growing literature on tailored print health behavior change interventions, it is currently not known if or to what extent tailoring works. The current study provides a meta-analytic review of this literature, with a primary focus on the effects of tailoring. A comprehensive search strategy yielded 57 studies that met inclusion criteria. Those studies-which contained a cumulative N = 58,454-were subsequently meta-analyzed. The sample size-weighted mean effect size of the effects of tailoring on health behavior change was found to be r = .074. Variables that were found to significantly moderate the effect included (a) type of comparison condition, (b) health behavior, (c) type of participant population (both type of recruitment and country of sample), (d) type of print material, (e) number of intervention contacts, (f) length of follow-up, (g) number and type of theoretical concepts tailored on, and (h) whether demographics and/or behavior were tailored on. Implications of these results are discussed and future directions for research on tailored health messages and interventions are offered.  相似文献   
760.
Animal analogue studies show that damaged adult brains reorganize to accommodate compromised functions. In the human arena, functional magnetic resonance imaging (fMRI) and other functional neuroimaging techniques have been used to study reorganization of language substrates in aphasia. The resulting controversy regarding whether the right or the left hemisphere supports language recovery and treatment progress must be reframed. A more appropriate question is when left-hemisphere mechanisms and when right-hemisphere mechanisms support recovery of language functions. Small lesions generally lead to good recoveries supported by left-hemisphere mechanisms. However, when too much language eloquent cortex is damaged, right-hemisphere structures may provide the better substrate for recovery of language. Some studies suggest that recovery is particularly supported by homologues of damaged left-hemisphere structures. Evidence also suggests that under some circumstances, activity in both the left and right hemispheres can interfere with recovery of function. Further research will be needed to address these issues. However, daunting methodological problems must be managed to maximize the yield of future fMRI research in aphasia, especially in the area of language production. In this review, we cover six challenges for imaging language functions in aphasia with fMRI, with an emphasis on language production: (1) selection of a baseline task, (2) structure of language production trials, (3) mitigation of motion-related artifacts, (4) the use of stimulus onset versus response onset in fMRI analyses, (5) use of trials with correct responses and errors in analyses, and (6) reliability and stability of fMRI images across sessions. However, this list of methodological challenges is not exhaustive. Once methodology is advanced, knowledge from conceptually driven fMRI studies can be used to develop theoretically driven, mechanism-based treatments that will result in more effective therapy and to identify the best patient candidates for specific treatments. While the promise of fMRI in the study of aphasia is great, there is much work to be done before this technique will be a useful clinical tool.  相似文献   
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