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This article focuses on gender differences in early heterosexual behaviour among Norwegian adolescents. The material comprised a random sample of 3000 Norwegian adolescents aged 17–19 years. The response rate was 63%. Data were collected by means of anonymous self-administered questionnaires. Sixty-nine per cent of the girls and 59% of the boys had had sexual intercourse. The majority of the adolescents, and a larger percentage of girls than of boys, had their first intercourse within a relationship of mutual commitment. The boys' first coital partners were 0.2 years younger than the boys themselves and the girls' partners were 2.8 years older than were the girls. Boys had had more coital partners than girls but girls had had intercourse more often than boys. Coital frequency was affected more by how long the adolescents had known the partner than by gender as such. In conclusion, boys and girls aged between 17 and 19 years form part of couples at two different stages of development. For this reason, boys and girls accumulate different sexual experiences in the early stage of their sexual careers.  相似文献   
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Thirsty rats were used in order to determine whether a vinegar solution, which had been paired with an injection of lithium chloride, could block the formation of an association between a pentobarbital- and a lithium chloride-induced state. During phase 1 the rats in the blocking group had a 2.0% vinegar solution paired with an injection of 240 mg/kg of lithium chloride, during phase 2 these rats were reexposed to the vinegar prior to each injection of 20 mg/kg of pentobarbital and 240 mg/kg of lithium chloride, and during phase 3 these rats were given access to a novel 0.75% saccharin solution and were injected with pentobarbital after saccharin removal. Animals with this history did not form an association between the pentobarbital- and lithium chloride-induced states during phase 2 as evidenced by their refusal to consume the saccharin solution over repeated pairings of saccharin with pentobarbital during phase 3. Control groups that received forward pairings of pentobarbital and lithium chloride, in the absence of a previously conditioned vinegar solution during phase 2, formed an association between pentobarbital and lithium chloride. These findings indicate that drug states and flavors can interfere with each others' capacity to predict the occurrence of lithium chloride.  相似文献   
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Introduction     
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The relation between awareness of body topology and auditory comprehension of body part names was studied in 22 aphasic subjects. Two nonverbal tasks—human figure drawing and placement of individual body parts in relation to a drawn face—were compared with two auditory tests of body part comprehension. The two nonverbal and the two verbal tasks were closely correlated with each other, but there was no relation involving either of the verbal tests with either of the nonverbal tests. Selection errors in the auditory comprehension tasks were predominantly semantically based and equally distributed between functionally analogous parts and parts related by location on the body.Dr. Benedet's effort in this study was supported by a grant from the Hispano-North American Joint Committee for Cultural and Educational Cooperation.  相似文献   
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This work has received financial support from FONDECYT (Project 1111-88). The authors also acknowledge the helpful comments of Dr. Bruce Cassels.  相似文献   
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This study examined the ability of both an overt integrity test and a personality-based measure of delinquency to predict on-the-job theft and counterproductivity. A heterogeneous sample of 105 employees anonymously completed both tests and a criterion checklist that included a 9-item theft subscale and a 12-item counterproductivity subscale. Results indicated that the overt integrity test was a superior predictor of both on-the-job theft and drug abuse compared to the personality-based measure. The overt integrity test was also a slightly better predictor of general counterproductivity. These findings and their implications are discussed.  相似文献   
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