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981.
Sex differences in the effects of gonadectomy on amphetamine-induced rotational behavior in rats 总被引:2,自引:0,他引:2
The effects of gonadectomy on amphetamine-induced rotational behavior were studied in male and female rats. Different systemic doses were used to produce equivalent brain concentrations of the drug in each group, thereby controlling for sex differences in the metabolism of amphetamine. Ovariectomy of female rats significantly attenuated amphetamine-induced rotation, whereas castration of males was without effect. The results support the idea that in females, the endogenous gonadal hormones facilitate functional activity in the mesostriatal dopamine system. 相似文献
982.
Initial environment influences amphetamine-induced stereotypy: subsequently environment change has little effect 总被引:1,自引:0,他引:1
Saline-treated and amphetamine-treated (7 mg/kg, ip, immediate) male rats from a Sprague-Dawley substrain were observed in two test environments designed to elicit different investigative responses in normal rats. Snout contact with the substrate was generated by placing the rat in a small enclosed cage. Absence of snout contact was induced by placement of the rat on a square elevated platform. Detailed ethological records were kept of locomotion, rearing, sitting, grooming, gnawing, and sleeping throughout the 90-min session. Amphetamine-treated rats incorporated environmentally contingent bodily postures into their forms of stereotyped behavior. The postures were characteristic of those evinced initially by the saline-treated rats in the same test environment. The control rats showed appropriate changes in their investigative behavior when the apparatus was changed at 10 and at 30 min postinjection. The amphetamine-treated rats, however, were completely unresponsive to such changes at 30 min and only partially so at 10 min postinjection. It was concluded that there is a temporal gradient of decreasing readiness to modify repetitive behavior after a single, large dose of amphetamine. 相似文献
983.
This paper compares LD and non-LD peers on eight variants of the oddity task. This study is part of a larger programmatic research effort aimed at the development of a screening test to detect preschool children who currently pass existing screening tests but, nonetheless, subsequently experience school failure. The theoretical orientation of this approach is to assess active, ongoing cognitive processing ability. The oddity task, which can be structured to assess such processing ability, was evaluated in the present study as a potential component of this screening test. Consistent with a priori predictions, the data resulted in strong group and developmental differences. Oddity performance increased over age, with the non-LD children performing consistently better than their LD peers at each age. Perceptual and conceptual factors were manipulated across the oddity variations, and both factors contributed to group differences. These results were discussed in relationship to early diagnosis and prognosis for learning disabilities that might result from deficiencies in abstract processing ability.The authors would like to express their thanks to the schools, teachers, and students who participated in this study. This research was supported in part by the Mailman Foundation and FDLRS/MAILMAN, a specialized university center of the Florida Diagnostic Learning Resources System, funded through State General Revenue appropriation to provide multidisciplinary evaluation services in exceptional student education programs. 相似文献
984.
J. Douglas Rodick Scott W. Henggeler Cindy L. Hanson 《Journal of abnormal child psychology》1986,14(1):77-87
Two basic assumptions of the Circumplex Model of family systems were evaluated: (1) Healthy families evidence balanced degrees of cohesion and adaptability, whereas problem families evidence extreme degrees, and (2) families with balanced degrees of cohesion and adaptability possess more positive communication skills than families with extreme degrees. Subjects were 58 mother-son dyads from father-absent families. In 29 of the families the adolescent was a juvenile offender, while in the remaining families there was no history of arrest or psychiatric referral. The dyads completed the Family Adaptability and Cohesion Scales (FACES) and an unrevealed differences interaction task. FACES was highly proficient at differentiating delinquent from nondelinquent families. Moreover, in families with balanced degrees of cohesion and adaptability, the mothers' communication was significantly more supportive and explicit, and the dyads evidenced significantly greater warmth and affection than dyads with extreme degrees.This research was supported by funding to the Department of Psychology at Memphis State University granted through the Centers of Excellence Program of the State of Tennessee. We thank the staff of the Memphis-Metro Youth Diversion Project for their consideration and assistance. 相似文献
985.
Sustained attention in children at risk for schizophrenia: Findings with two visual continuous performance tests in a new sample 总被引:1,自引:0,他引:1
J. Rutschmann Barbara Comblatt L. Erlenmeyer-Kimling 《Journal of abnormal child psychology》1986,14(3):365-385
In partial replication of an earlier study, 35 children at high risk for schizophrenia, 25 children at high risk for affective disorder, and 53 normal control children from a new sample of 7- to 12-year-old subjects were tested with two new visual continuous performance tests. Response levels and intrasubject variability were analyzed separately. Multivariate analyses on factor scores derived from response levels indicate that "groups" is a significant predictor for a factor reflecting discriminability (or sensitivity) for the more difficult of these tests but not for the less difficult one, and that high risk for schizophrenia is associated with lower performance. Factor scores and multiple regression analyses were used to dichotomize subjects as to whether or not they are low performance outliers. A significantly larger proportion of subjects from the high risk for schizophrenia group than from the control groups were low performance outliers. Among subjects that developed psychopathology in adolescence, subjects at high risk for schizophrenia were more likely to have contributed low performance outliers early during childhood. 相似文献
986.
987.
Measures adapted from social survey research were used to assess the quality of life of 33 end-stage renal disease (ESRD) patients in a 2-week test-retest design that varied both location and format of administration (hospital interview vs. home self-administered questionnaire). The measures were found to have substantial consistency over time, location, and format. These results indicate that quality of life is a stable construct and support the usefulness of questionnaire quality-of-life measures for evaluating medical interventions. 相似文献
988.
B Curbow 《Health psychology》1986,5(4):375-391
Medicaid proposals increasingly focus on cost-saving strategies that restrict clients' control over where and when they may receive services. This study used a field experiment in an urban welfare office to examine the possible effects of two aspects of restrictive policies: the loss of choice of providers and adverse patient mix (i.e., when the majority of a provider's clients are Medicaid beneficiaries). Results indicate that health care presented within the context of not having a choice is derogated and that choice and patient mix combine to influence intentions to seek care. Persons who did not choose the health plan in a simulated choice, who had fewer choices than expected, and who did not accept restricted choice also had negative perceptions. 相似文献
989.
Male and female volunteers (N = 144) answered the Reactivity Scale (RS) and underwent testing for their perceived intensity and tolerance for finger-pressure pain. Half the Ss were randomly assigned to a low-intensity treatment (1150 g) and half to a high-intensity treatment (2300 g). Pain was rated at 30 and 60 sec., and Ss were asked to endure it as long as possible up to 5 min. The major findings were as follows: (1) women outscored men on reactivity; (2) the three pain measures intercorrelated highly; (3) high-intensity stimulation produced higher pain ratings and shorter tolerance than did low-intensity stimulation; (4) men gave lower intensity ratings than women and tolerated the pain longer; (5) reactivity related positively to judged pain at 30 and 60 sec, and negatively to pain tolerance; (6) there were no significant interaction effects among stimulus intensity, sex and reactivity for any pain measure; (7) the variance in the pain measures accounted for by stimulus intensity, sex and reactivity ranged from 26 to 32%. The implications were briefly discussed for the validity of the RS and factors explaining responses to experimentally-induced pain. 相似文献
990.
Twenty-six previous studies were reviewed which demonstrated a consistent link between children's smoking uptake and exposure at home to an actively smoking older family member. The present study included another variable: the family model of smoking cessation. The smoking practices, intentions, and attitudes of 344 children aged 10–14 in Western Australia were anonymously assessed. Those with ex-smokers but no active smokers at home resembled children who had never been exposed to a smoking family model in being less likely to smoke now or intend to in the future, having fewer smoking chums, and believing that cigarettes had more personal and social disadvantages than their peers who shared households with active smokers. This suggested that any pro-smoking modeling while the ex-smoker was active had been counteracted by modeling of quitting. Implications for intervention were discussed. 相似文献