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161.
The available defensive mechanisms are generally sufficient to protect the central nervous system (CNS) against the penetration of infectious particles. The blood-brain-barrier plays a decisive role in this process. The present paper represents the most important circumstances realizing that: 1. The macrophage-lymphocyte-system, 2. the "oligoclonal-CSF-IgG-reaction", and 3. the influence of psychological and physiological burdens on clinical-chemical or immunological parameters. It seems to be important to overcome the instability of the immunosystem and to reestablish the base-line.  相似文献   
162.
Three studies were conducted to test whether a catecholamine training effect results from a long-term aerobic exercise program. Study I showed significant increases in urinary adrenaline and noradrenaline following moderate mental stress/challenge for male aerobics subjects after a semester of training. Control groups of nonexercisers and continuously in-condition marathoners showed no comparable pre- to post semester catecholamine increases. Male and female Aerobics subjects were contrasted with nonexercisers across a semester in Study 2; the hypothesis was confirmed that postsemester increases in catecholamines occurred only following an episode of mental challenges/stress, and not following base-rate-rest conditions. Under conditions of more active challenge than in Studies 1 and 2, women subjects in Study 3 provided directional but nonsignificant support for the Study 2 findings. The results are discussed in the context of literature on the relationship of catecholamine availability during challenge/stress to temperament and on the relationship of aerobic training to temperament. At a theoretical level, the question is discussed of increased catecholamine availability being a likely mediator in the exercise program to temperament relationship.This research was supported by a grant from the Research Council of the University of Nebraska Lincoln. Our thanks to Prof. James Crabbe for assistance in recruiting subjects in Study 2, and to Pamela Brown and Prof. Wes Sime for assistance with Study 3.  相似文献   
163.
Four experiments demonstrate that when putative conditional and discriminative cues are presented simultaneously in the single reversal procedure, it is not possible to ascribe a uniquely conditional or uniquely discriminative function to either of the cues. In Experiment 1, pigeons were trained to respond to a blue key and not to a red key while the houselight was on; then in a different session they learned the reversal of this discrimination with the houselight off (single reversal). Separate groups were tested for color generalization with houselight conditions alternating in blocks of trials or for houselight intensity generalization with blue and red key colors alternating in blocks of trials. Both test procedures revealed a conditional relationship between houselight and key color conditions. Experiment 2 produced the same result following training in which the key colors were held constant across training sessions while the houselight and no houselight conditions varied within sessions. In Experiment 3, separate groups were trained with the two procedures but were tested with randomly ordered combinations of key colors and houselight intensities. The two groups yielded indistinguishable bidimensional generalization gradients with peaks at both previously reinforced stimulus combinations. In Experiment 4 the subjects were switched from one of these training procedures to the other with no decrement in their discriminative performance. We conclude that for successive discriminations between conditional- and discriminative-stimulus combinations, the notion of a hierarchical relation between conditional and discriminative stimuli must be extended to include a symmetrical relationship or the notion should be abandoned altogether.  相似文献   
164.
The study was designed to assess the stability of WISC-R profiles of 36 learning disabled children given the WISC-R two times. The mean time between tests was 2.5 yr. The pattern reported for learning disabled children on Bannatyne's categories was evident for the group at both times, however, this pattern was not found for the majority of subjects. Analysis indicated a decrease over time in Verbal IQs, Full Scale IQs, and Bannatyne's Conceptual category, confirming previous findings. Possible reasons for the changes in scores are discussed.  相似文献   
165.
Starting from the basic ideas of sociobiology we prove that Schopenhauer, in his "Metaphysics of Sexual Love", has to pass for a precursor of sociobiological thinking. Several consequences of this parallel are discussed: The quest for strategic principles of organismic growth and evolution as a positive characteristic of both approaches--the hypothesis of a dominant genetic determination of human behaviour as an outcome of a typical bourgeois view of mankind connecting Schopenhauer and sociobiologists--the necessity of taking into consideration biological predispositions of flexible (learned) behaviour as elements of sociobiological models enjoying the same rights as genetical ones--the utility of Schopenhauer's natural philosophy for the purpose of complementing historical knowledge of many disciplines (also psychology).  相似文献   
166.
To examine the interrelationships of MMPI scale scores among low back pain patients, 50 profiles were scored on the traditional 13 scales, Hanvik's Lb scale and seven subscales derived from Scales 1 and 3. The profiles were randomly divided into two equal samples and factor analyzed. Comparison of the two samples yielded three common factors. The first factor measured severity of the symptoms, the second assessed the level of anger and aggression and the third assessed the psychogenic components of the syndrome. The implications of the factors are discussed.  相似文献   
167.
In perceiving objects we may synthesize conjunctions of separable features by directing attention serially to each item in turn (A. Treisman and G. Gelade, Cognitive Psychology, 1980, 12, 97–136). This feature-integration theory predicts that when attention is diverted or overloaded, features may be wrongly recombined, giving rise to “illusory conjunctions.” The present paper confirms that illusory conjunctions are frequently experienced among unattended stimuli varying in color and shape, and that they occur also with size and solidity (outlined versus filled-in shapes). They are shown both in verbal recall and in simultaneous and successive matching tasks, making it unlikely that they depend on verbal labeling or on memory failure. They occur as often between stimuli differing on many features as between more similar stimuli, and spatial separation has little effect on their frequency. Each feature seems to be coded as an independent entity and to migrate, when attention is diverted, with few constraints from the other features of its source or destination.  相似文献   
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