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831.
To evaluate expectations derived from ego-identity theory and symbolic-interaction theories about the association between self-concept and peer-group affiliations in adolescence, we examined the self-esteem of 221 7th through 12th graders associated by peers with one of five major school crowds and 106 students relatively unknown by classmates and not associated with any school crowd. Among crowd members, self-esteem was directly related to the position of one's crowd in the peer-group status hierarchy (based on both peer-rated and self-perceived crowd affiliation). Outsiders' self-esteem differed in relation to the accuracy of their reflected appraisal of and the salience they attached to crowd affiliation. Crowd members as a whole exhibited higher self-esteem than outsiders as a whole. Differences, however, were mediated by crowd status, salience of crowd affiliation, and the accuracy of reflected appraisals. An adequate interpretation of the findings required an integration of Festinger's (1954, 1957) social comparisons and cognitive-dissonance theories, Cooley's (1902) notions of reflected appraisal, and Newman and Newman's (1976) extrapolations from ego-identity theory.  相似文献   
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The results of an evaluation of the perfusion scintigraphy findings of 350 hospitalised neurological patients and 55 more strictly selected neurosurgical patients with cerebrovascular complaints, revealed an accuraty of 83%, a sensitivity of 89%, and a specificity of 83%. The selection of the patients had no influence on the results as a whole. Compared with contrast-medium angiography, incorrect diagnosis must be expected in 17% of the cases. This includes erroneous negative findings in 10% of the cases. Grounds for misinterpretations are suggested, and the biological and methodological limitations of the method are set forth.  相似文献   
836.
The paper investigates 54 myelograms and their influence on diagnostic thinking efficacy, on patient management efficacy, and on ultimate outcome efficacy, using statistical methods. Conventional myelography contributes to diagnostic thinking efficacy having a LLR- value of approximately 0.9. With an accuracy value of 0.95 it can be regarded as a reliable method of diagnosis. It alters diagnostic thinking efficacy in no less than 83% (94%) of the cases and patients management efficacy in 89%. Thus, by definition, myelography may be said to affect the state of health of the myelographed patients in 94.4%.  相似文献   
837.
This article attempts to apply a theory of aggression as motivation to overcome obstacles to the understanding of phobic states and their formation. The role of aggression in the genesis of phobic conditions is discussed, and the traditional analytic view of aggression as instinctual drive is contrasted with a motivational approach. The motivational view offers the advantage of a clearer understanding of the stimulus contexts, representational connections, and both real and imaginary object connections that are lacking in the more traditional understanding of aggression as a biological drive.  相似文献   
838.
Four of our own cases that presented a clinical picture of dementia are discussed. A study of the relative literature has failed to reveal any "swing" in the pattern of the clinical condition: Just as it did ninety years age, paralytic dementia accounts today for well over 60% of all cases, those clinical pictures erroneously regarded as "typical" "classic", accounting for a mere 10%-15% of cases. The need for routine lues serology is pointed out.  相似文献   
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