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61.
Inhibitory avoidance deficit following short-term adrenalectomy in the rat: the role of adrenal catecholamines 总被引:4,自引:0,他引:4
Impaired retention of an inhibitory avoidance response was observed in rats subjected to adrenalectomy (ADX) up to 120 hr before the single learning trial. Corticosterone substitution failed to normalize this behavioral deficit. Rats ADX 240 hr prior to the learning trial showed a normalized behavior. Adrenomedullectomy (ADXM) 48 or 240 hr before learning caused a similar impairment as in short-term ADX rats. The 240-hr ADX rats subjected to corticosterone substitution showed the same behavioral deficit as short-term ADX rats or ADXM ones. Immediate postlearning subcutaneous injection of adrenaline in a dose range of 0.005-5.0 micrograms/kg or of noradrenaline (0.005-0.5 microgram/kg) to 48-hr ADX rats resulted in a dose-related improvement of later retention behavior. Higher doses of catecholamines were less or ineffective. Postlearning treatment of 48-hr ADXM rats with adrenaline (0.5-500 micrograms/kg) caused a similar pattern of behavioral changes. It is concluded that adrenal catecholamines play an important role in the modulation of consolidation of memory. In addition, the high circulating ACTH levels that follow long-term ADX may correct for the behaviorial deficit induced by the absence of adrenomedullary catecholamines. 相似文献
62.
In this study, we examined variations in fathering and father-child relationships from the children's preschool years through mid-adolescence. One hundred seventy-seven fathers with first-born children ages 4, 8, 12, and 16 years responded to five sets of questionnaires tapping four domains of childrearing: practices, attitudes, parental role involvement, and role satisfaction. A multivariate analysis of variance identified significant variability among the four age groups in fathers' use of acceptance in childrearing practices, role involvement (frequency and task sharing), satisfaction with paternal role performance, and attitudes about the modifiability of child behavior. The results contribute new information about the nature of fathering throughout the childhood years and adolescence and provide additional support for the view of parenting as dynamic and responsive to the developmental level and gender-related characteristics of the child. 相似文献
63.
Jos De Mul 《Man and World》1991,24(4):409-426
Paper delivered at theEighth International Human Science Research Conference at Aarhus University (Denmark), 18–22 August 1989. 相似文献
64.
An alternating least squares method for iteratively fitting the longitudinal reduced-rank regression model is proposed. The method uses ordinary least squares and majorization substeps to estimate the unknown parameters in the system and measurement equations of the model. In an example with cross-sectional data, it is shown how the results conform closely to results from eigenanalysis. Optimal scaling of nominal and ordinal variables is added in a third substep, and illustrated with two examples involving cross-sectional and longitudinal data.Financial support by the Institute for Traffic Safety Research (SWOV) in Leidschendam, The Netherlands is gratefully acknowledged. 相似文献
65.
Pierre Philippot Norbert Schwarz Pilar Carrera Nannes De Vries Nico W. Van Yperen 《European journal of social psychology》1991,21(4):293-302
Two experiments investigated whether the direction of priming effects depends on the processing stage at which the individual links the prime to a trait that is applicable to the evaluation of an ambiguously described target person. In line with previous research, it is hypothesized that assimilation effects will emerge when primes are processed in terms of a trait concept that is applicable to the encoding task. However, when the primes are not processed in applicable trait terms, they may still affect subsequent Judgments if the individual recalls the prime when judging the target along a trait dimension. In this case, the primes may serve as an anchor, resulting in contrast effects. Two experiments, in which subjects were primed with names of prototypically nice or hostile famous individuals under instructions that did or did not prompt subjects to process the prime in applicable trait terms, supported these hypotheses. Implications for the emergence of priming effects in everyday social interaction are discussed. 相似文献
66.
This paper considers some mathematical aspects of minimum trace factor analysis (MTFA). The uniqueness of an optimal point of MTFA is proved and necessary and sufficient conditions for a point x to be optimal are established. Finally, some results about the connection between MTFA and the classical minimum rank factor analysis will be presented. 相似文献
67.
68.
Andre De Vries 《Theoretical medicine and bioethics》1982,3(1):115-120
Recently, the attitude and performance of the physician have been questioned and new codes of medical ethics have been introduced. Any ethics proposed for the future is a scenario reflecting the composer's selectivity. Envisaged ethics of truthful, non-paternalistic, responsible physician-patient interaction will have far-reaching implications for autopsy, euthanasia, abortion, suicide, genetic engineering, transplantation, clinical trials, status of the psychiatric patient, physician immunity and liability. Conflicts between personal and societal medical ethics may continue to be insoluble. A possible projection of the physician's ethics on that of the politician is discussed. A new medical ethics should encompass principles of different creeds and be supranational. 相似文献
69.
Henry J. De Haan 《Attention, perception & psychophysics》1982,32(1):27-31
The relationship between subjective estimates of the comprehensibility of connected, freerunning speech and rate of speech was investigated for each of two types of time-compressed speech: pitch-varying speeded speech and pitch-normalized compressed speech. The midpoints of the resulting functions approximated the values obtained by a previously described speechrate tracking method. For equivalent degrees of comprehensibility, rates were higher for compressed speech than for speeded speech, indicating that estimates are sensitive to the intelligibility of speech. Subjective estimates of comprehensibility of time-compressed speech provide a means of assessing the itelligibility of connected speech. 相似文献
70.
Two pigeons were trained to peck a key under a free-operant avoidance schedule. Then, changes in key color signalled the beginning (safe period) and the end (warning period) of the response-shock interval, with a response required to change the key color. Finally, a change in key color signalled the warning period and either a response or a shock reinstated the safe stimulus. During signalled avoidance, response rate was higher during the warning stimulus than during the safe stimulus. More responding tended to occur in the warning stimulus when it was terminated by either a response or a shock than by only a response. In either procedure, response latency during the warning stimulus was a function of the duration of the warning stimulus. In general, response and shock rate were higher during unsignalled than during signalled avoidance. When the warning stimulus was brief, the results were similar to those of unsignalled avoidance. These results confirm previous findings with pigeons, are in general agreement with data provided by other species in studies of signalled avoidance, and thereby indicate the transituationality of the key-pecking operant. 相似文献