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141.
Simonik Diane K.; Robinson Scott R.; Smotherman William P. 《Canadian Metallurgical Quarterly》1994,108(6):1179
Rat fetuses were exposed to cocaine, lidocaine, or saline on Gestational Day 20 or 21 to provide information about cocaine effects on behavior during prenatal development. Cocaine was administered into the cisterna magna of individual fetal subjects to restrict effects to the CNS. Behavioral effects of cocaine were compared with lidocaine to help distinguish the effects of cocaine on monoamine systems in the brain from its properties as a local anesthetic. Cocaine promoted 3–5 fold increases in fetal motor activity in the absence of explicit sensory stimulation, in contrast to the slight suppressive effects of lidocaine. Cocaine and lidocaine also reduced coordinated behavioral responses to an artificial nipple. The behavioral effects of cocaine administered into the CNS of fetal subjects suggest specific mechanisms of action on developing neural and behavioral systems in the late prenatal period. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
142.
Parkerson Jo A.; Lomax Richard G.; Schiller Diane P.; Walberg Herbert J. 《Canadian Metallurgical Quarterly》1984,76(4):638
Evaluated 5 causal models of educational productivity as they apply to learning science among 882 5th–8th graders. Each model explores the relationship between achievement, as assessed by the Comprehensive Test of Basic Skills, and a combination of 8 constructs: home environment, peer group, media, ability, social environment, time on task, motivation, and instructional strategies. Linear structural-relations analysis was employed to examine each of the models. The complex theoretical model had significant (positive) coefficients for all the constructs except quality of instruction; goodness-of-fit indices showed it was the best fitting model with the lowest average residual size. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
143.
Investigated the effects of response cues (erotic, romantic, or neutral) and level of sex guilt on the self-reported sexual fantasies of 90 undergraduate females. Ss completed a sex guilt inventory (Masher Forced-Choice Guilt Inventory—Female Form), the Nowlis Mood Adjective Check List, the Fantasy Theme Checklist, and ratings of their affective responses and physiological arousal associated with the writing of the fantasies. High sex guilt Ss preferred fantasy themes indicating a lack of responsibility for engaging in sexual interaction. Ss in the erotic fantasy condition wrote more explicit fantasies and described more varied content. Arousal seemed to be affected by the response cuing in the predicted direction but not by the Ss' guilt levels. Sex guilt level seemed to be a better predictor of affective responses, such as guilt and embarrassment, than the response cuing. Results suggest that sexual fantasy behavior may be part of a cluster of sexual behaviors governed by an individual's level of sex guilt. It is suggested that the demonstration that fantasy production seemed to be influenced by situational demands has implications for collection and use of fantasy information by both clinicians and researchers. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
144.
Thin sections of nervous tissue were viewed at different tilt angles using a transmission electron microscope equipped with a eucentric goniometer stage. In a comparison study of various degrees of tilt, one can observe additional morphological features within synaptic profiles, define subsynaptic structures such as Taxi-bodies, and clearly see the crystalline formation of cytochemical tracers. This study demonstrates the value of tilting thin-sections in the analysis of synapses and other biological material at the ultrastructural level. 相似文献
145.
Deutsch Francine M.; Ruble Diane N.; Fleming Alison; Brooks-Gunn J.; Stangor Charles 《Canadian Metallurgical Quarterly》1988,55(3):420
The self-definitional processes accompanying the transition to motherhood were examined in this study. A cross-sectional sample of more than 600 women who were planning to get pregnant within 2 years, pregnant, or in the postpartum stage completed extensive questionnaires pertaining to their experiences of pregnancy and motherhood. On the basis of the assumption of the "self-socialization" perspective that individuals actively construct their identities in response to life transitions, our analyses focused on the role of information-seeking in the developing self-definitions of women becoming mothers. As predicted, (a) women actively sought information in anticipation of a first birth, (b) they used this information to construct identities incorporating motherhood, and (c) after the birth the determinants of their self-definitions shifted from indirect sources of information to direct experiences with child care. Hence, consistent with the self-socialization perspective, information-seeking did play an important role in the women's developing self-conceptions during this life transition. Mechanisms by which information gathered may alter self-conception are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
In order to track neuropsychological recovery as a function of age more precisely than in prior studies, 31 alcoholics were divided into 3 age groups (20–29, 30–39, and ≥ 40 yrs) and administered a repeatable neuropsychological test battery for the 3 mo immediately following cessation of drinking. Two control groups (15 college students and 15 individuals ≥ age 40 yrs) were also tested to assess practice effects, optimal test performance, and age-related test performance. Prior research has shown the tests used are sensitive to alcohol-related dysfunction and other transient drug toxicity. A variety of alcohol consumption and demographic variables were also studied as predictors of performance deficits. Results show that (a) alcoholics below age 40 yrs recovered completely from functional impairment by 2–3 wks after drinking ceased, and (b) alcoholics aged ≥ 40 yrs failed to recover over 3 mo on some but not all visuo-spatial tasks. Results suggest that beyond 40 yrs, humans increase in vulnerability to the toxic effects of alcohol or are less able to compensate for impairment of the neurological substrate. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
147.
Investigated preschoolers' knowledge of counting principles by examining their ability to discriminate between features that are essential for correct counting and features that are typically present but unessential. The standard counting procedure was analyzed into 1 essential feature, word/object correspondence (WOC), and 4 optional features: counting adjacent objects consecutively, pointing once to each object, starting at an end of a row, and proceeding in a left to right direction. In Exp I, 10 3-, 10 4-, and 10 5-yr-olds were asked to judge a puppet's counting that either violated the essential or unessential features or that conformed to the standard correct procedure. Ss who knew the WOC principle presumably would reject counts that violated it more often than counts that conformed to it. Each S's skill in counting rows of objects also was assessed. In Exp II, 16 3-yr-olds completed a similar task but were able to see an adult model perform the task before judging. Skill in executing the standard counting procedure preceded knowledge of the underlying principle. Four- and 5-yr-olds knew that WOC was essential, although a high percentage of them did not know that other typical features were unessential. An analysis of probable environmental input and of the features' utility in separating already-counted from to-be-counted objects is proposed to account for the relative probabilities that Ss knew that each of the 5 features of standard counting was essential or optional. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
Poulin-Dubois Diane; Serbin Lisa A.; Kenyon Brenda; Derbyshire Alison 《Canadian Metallurgical Quarterly》1994,30(3):436
The aim of this study was to seek evidence of intermodal knowledge about gender in infants that would provide direct evidence of the existence of gender categories during the 1st yr of life. In Exp 1, 20 9- and 24 12-mo-olds were presented with pairs of male and female pictures with a female or male voice presented simultaneously. Ss spent significantly more time looking at the pictures matching the voices than at the same pictures paired with mismatching voices, but only in the case of female stimuli. Comparison to chance level performance suggested that the matching effect was more consistent in older Ss. In Exp 2, 20 9-mo-olds were tested with a set of highly stereotypical faces and distinctive male and female voices. Ss showed a preference for the faces matching the voices, but this effect was again restricted to female stimuli. Results of both studies suggest that intermodal knowledge about gender develops during the 2nd half of the 1st yr. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
Sex role stereotyping of college professors: Bias in students' ratings of instructors. 总被引:1,自引:0,他引:1
We investigated the impact of three variables on students' ratings of instruction (SRIs): social contact between instructor and students (present vs. absent), the instructor's facial expression (smiling vs. neutral), and the instructor's sex. Subjects were presented with hypothetical scenarios in which these factors varied while behaviors directly related to teaching were held constant. Results revealed an interaction between instructor sex and both of the other two factors: Behaviors indicative of friendliness toward students elevated SRIs for female instructors but not for male instructors. In addition, subjects rated the male professors as more effective than female professors. These findings are consistent with other reports that students expect female instructors to excel in both stereotypically masculine (e.g., competence) and feminine (e.g., warmth) domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
150.
Let X be a random variable such that In [(X - ?)/?] has a s-normal distribution with mean zero and variance one. Then X has a 3-parameter lognormal distribution with the third parameter, the shape parameter, fixed at unity. This paper presents the coefficients required to construct the best linear unbiased estimators (BLUEs) of ? and ? for samples of size fifteen and less. The variances and covariances of these estimators are provided. These estimators yield the BLUEs of the mean, standard deviation, and percentiles of X since these quantities are linear functions of ? and ?. Blom's estimators and maximum likelihood estimators compare favorably with the BLUEs. 相似文献