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871.

Treatment of rats with the potent antiaggressive compound eltoprazine hydrochloride (1.0 & 2.0 mg/kg) slowed both predatory attack and killing of frogs. These results demonstrate a specific predation-inhibiting action of the drug which is not obscured by the elements of conspecific aggression seen during muricide. Unlike the closely related compound fluprazine, eltoprazine increased both attack and kill latencies implying that the effects of the two drugs on predation are mediated by at least somewhat distinct drug actions. It is further suggested that eltoprazine may be more specifically antiaggressive in its actions than related phenylpiperazine compounds.

  相似文献   
872.
319 3rd and 5th grade children were asked to rate their parents' job satisfaction. These ratings were compared to parents' self-reports of job satisfaction. Older children were more accurate in their estimates. Girls were more accurate in rating their mothers, while boys were more accurate in rating fathers. Children who perceived their parents as satisfied with their jobs were more likely to aspire to their parents' occupations than those who rated their parents less satisfied.  相似文献   
873.
Effect of boredom proneness on time perception   总被引:1,自引:0,他引:1  
As part of a larger study examining attribution differences in boredom, the effect of Boredom Proneness on perception of time passage was investigated in 110 undergraduates completing a tedious number-circling task. Highly boredom-prone individuals perceived time as passing more slowly during the task than low boredom-prone persons, but the two groups did not differ in their objective or chronometric time-passage estimates. The findings support the contention that depressed affect produces a subjective slowing of time but does not alter the perception of objective passage of chronometric time.  相似文献   
874.
Considers a preventive intervention effort designed to modify the characteristics and regularities of the school environment so as to enhance the expectations conveyed to high risk students. Employing this case effort (Weinstein et al., 1991) as a base, several issues are highlighted that deserve greater attention in the design, implementation, assessment, and reporting of other preventively-focused social interventions. These issues include: (1) the degree of program implementation fidelity, (2) the impact a lack of attainment of program fidelity may have on arriving at erroneous evaluation conclusions about social programs, (3) the ways in which the theory and basic research employed in the program rationale is appropriate to and reflected in the program as designed, (4) issues of program potency and dosage, (5) the ways in which quantitative and qualitative evaluation data can enhance each other, and (6) the import of evaluability assessments of programs prior to moving to outcome evaluations. In addressing these issues, the importance of developmentally- and ecologically-informed program formulations is underscored. Finally, the critical role that program reports such as the Weinstein paper, with its careful discussion of both the process of implementation and outcome assessments, can play in the development of more effective prevention program implementation efforts is highlighted.  相似文献   
875.
In this study of auditory prestimulation cues, picture naming performances under phonemic and semantic conditions were compared to picture naming performance under a neutral condition. Twenty aphasic subjects named 324 pictures (108 pictures x 3 conditions) each. Responses were scored using a coding system adapted by the investigator from classification systems used by Williams and Canter (1982) and Kohn and Goodglass (1985). Results indicated that naming accuracy was facilitated by phonemic and semantic cues. An examination of the distribution of errors under the three conditions revealed systematic effects of phonemic and semantic cues on the frequency of occurrence of specific error types. Increases in semantic paraphasia proportion scores and decreases in unrelated word error proportion scores were associated with the semantic condition, while increases in phonemic paraphasia proportion scores were associated with the phonemic condition. The finding that naming performance of aphasic adults varies as a function of the type of information provided by the cue is discussed in relation to cascade visual confrontation naming models.  相似文献   
876.
Task dynamics corresponding to rhythmic movements emerge from interactions among dynamical resources composed of the musculature, the link segments, and the nervous and circulatory systems. This article investigated whether perturbations of interlimb coordination might be effect over circulatory and nervous elements. Stiffness of wrist-pendulums oscillated at a common tempo and at 180 degrees relative phase was perturbed through the use of tonic activity about an ankle. Left and right stiffnesses, the common period, and the phase relation all changed. Stiffnesses increased with ankle torque in proportion to the wrist's inertial load. Despite different changes in stiffness at the two wrists, isochrony was preserved. The stability was shown to be consistent with the proportionality of changes in stiffness to the inertial loads. The phase departed from antiphase in proportion to the asymmetry of inertial loads. The size of departures decreased with increasing ankle torque. An account was developed in terms of muscular, circulatory, and nervous functions.  相似文献   
877.
878.
The authors propose a diagnostic for distinguishing between serial and parallel processing in visual search; it is based on testing for subadditive effects of a within-trial visual quality manipulation on target-absent trials. It was evaluated in 2 experiments wherein parallel and serial processing might be expected on the basis of previous work and was then applied to a more uncertain situation in a third experiment. The diagnostic indicates parallel processing of stimuli that differ from each other on a featural basis (Xs and Os) and canonical letters that differ in line arrangement (Ts and Ls) but serial processing when Ts and Ls are randomly rotated. These results form a coherent pattern that is understandable in terms of the literature on visual search, and thus they suggest that the diagnostic may be a useful addition to the methodology used to distinguish between serial and parallel processes.  相似文献   
879.
The presence of other Aplysia in the environment increases the time spent feeding. This finding is consistent with the hypothesis that a common arousal mechanism modulates feeding and reproductive behaviors. The arousal level is presumably increased by pheromones released by additional animals.  相似文献   
880.
Gender differences in health-related quality of life   总被引:1,自引:0,他引:1  
In 1986 the life expectancy at birth was 71.3 years for males and 78.3 years for females--providing a 7-year advantage for women. Although women live longer, it has been reported that they paradoxically experience more physical and psychological illnesses. In this article, we estimate the expected well-years or quality-adjusted life years for men and women in the general population. The data were obtained in a random sample of 1,034 residents of San Diego. The well-life expectancy uses standard life expectancies with adjustments for quality of life. The well-life expectancy for men was 59.8 years; for women, it was 62.7 years. Thus, the quality adjustment had significantly more impact on women (15.6 years) than on men (11.5 years). Age-specific estimates of health-related quality of life suggested a male advantage before age 45 and a female advantage after age 45. The benefits of well-years of life as a public health statistic are discussed.  相似文献   
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