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961.
962.
A N Gilbert 《Journal of comparative psychology (Washington, D.C. : 1983)》1984,98(3):232-245
Virgin rodents exhibiting cycling estrus have traditionally been used for comparative studies of reproductive behavior. However estrus occurs in other life-history contexts, some of which differ from cycling estrus (CE) in that (a) the female is disposed to behave both maternally and sexually and (b) they result in litter overlap (i.e., the simultaneous gestation and lactation of two litters). In this report, two of these other modes of estrus are examined, with emphasis on their evolutionary and ecological implications. By means of a literature search of the order Rodentia, postpartum estrus (PPE) and lactational estrus (LE) were documented in 15 families, 71 genera, and 141 species. Analysis of these data showed that PPE and LE were nonrandomly distributed across taxa. They were statistically overrepresented in the family Cricetidae and underrepresented in squirrels (Sciuridae) and in pocket mice and kangaroo rats (Heteromyidae). Analysis of the phenotypes by which PPE and LE are achieved suggests important differences between them and CE in several parameters of female reproductive effort and breeding strategy, including maternal and copulatory behavior, optimal timing of litters, and hormonal control of heat and lactation. 相似文献
963.
Smokers and nonsmokers were compared on three aspects of academic achievement. Although exactly the same percentage of smokers
and nonsmokers passed the first-year university examination, smokers obtained significantly higher marks. Similarly, smokers
achieved significantly higher marks in their final year examinations in comparison with nonsmokers. Finally, a comparison
of the tutorial essay marks of the smokers and nonsmokers again showed that smokers obtained significantly higher marks than
nonsmokers. These data are consistent with the idea that ambitious students adopt smoking in the belief that it will help
them study and sustain concentration. 相似文献
964.
Richard A. Griggs 《Current Psychology》1984,3(4):3-10
The present study examined the hypothesis that violation and role-playing instructions are necessary conditions for facilitation
on Wason’s selection task and that facilitation due to memory cueing via thematic content is secondary. The results of a factorial
experiment employing these factors did not support the hypothesis. Memory cueing was indicated as the primary factor, but
violation instructions did increase the amount of facilitation observed. This interactive effect and the nature of facilitation
by memory cueing are briefly discussed. 相似文献
965.
John B. Todman 《Current Psychology》1984,3(3):46-60
Problems involved in scaling the output regularities observed in free recall are outlined, and assumptions underlying attempted
solutions for both categorized and “unrelated” lists are discussed. Several studies that make claims for the superiority of
particular measures have indeed demonstrated that it matters which index is selected, but they are shown to provide no justification
for preferring one to another. Evidence from simulation studies, however, suggests that a number of measures have “built-in”
correlations with theoretically relevant variables such as recall. Some of these biases have proved elusive because their
appearance is confined to nonrandom output sequences. The relation between theoretical assumptions and simulation studies
is discussed. 相似文献
966.
967.
This paper discusses an exploratory investigation concerned with the long range questions: How does group psychotherapy help patients? and How can psychiatry residency programs best train residents to treat patients in therapeutic groups? Group psychotherapy has come to be accepted in its own right as a decisive contribution to the study of and relief of emotional disorders. As a component of comprehensive psychiatric services it is indispensable. However, while its clinical value has been demonstrated, its scientific validity has not. A Group Process Inventory has been developed by the author and has been utilized for the past two years by psychiatric residents in recording the process of their therapeutic groups in a teaching hospital mental hygiene clinic. The preliminary use of this recording as a clinical-teaching instrument has proven effective. This inventory is being revised to serve as a research instrument. 相似文献
968.
In the literature on cotherapy, little attention has been focused on maximizing the effectiveness of two therapists working in tandem with families and couples. While cotherapists may at times share their ideas and feelings with their clients, and after the therapeutic session exchange views between themselves, generally little interaction occurs between them during the session. In this paper, a case is presented for more active interactions between cotherapists during the session, in order to expedite and facilitate change and growth in their clients. Anecdotal examples are provided to illustrate the approach. 相似文献
969.
970.