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141.
Early postweaning experience in an enriched environment had a greater influence on the open-field behavior and body weight of wild Norway rats than of their domestic counterparts. Genetic changes accompanying the domestication process may have reduced the relative impact of postweaning experience on the development of the domestic rat's response to changes in its environment. 相似文献
142.
U Grimm A Knapp W Schmitz M Smetan K W Schmitz H Reddemann M Schulz K Schlenska 《Psychiatrie, Neurologie, und medizinische Psychologie》1975,27(11):675-681
In 8 selected test persons of the 3rd series of experiments who were showing signs of pathological kynureninase activity, hepatic kynureninase was again established after 3 week's treatment with large doses of vitamin B6. The enormous in-vivo activation of the kynureninasis established goes to prove that apoenzyme synthesis may be stimulated by pyridoxine. On the basis of these results and the relative frequency of disorders dependent on B6, the question arises whether children from endangered families should not be given prophylactic vitamin B6 treatment from birth. 相似文献
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Three experiments are described on the development of internal representations (IRs) of networks resembling city road maps when these are seen only part by part.In the first study four ways of extracting information from a subject about the structure of his IRs were compared under two modes of sequential part presentation establishing an absolute and a relative frame of reference, respectively. No differences were found between response or reference modes.The second study employed yet another reference mode, the egocentric, and varied the speed of presentation. It was found that in the egocentric mode subjects developed an adequate IR via a purely sequential stage of processing, while a part-to-whole strategy prevailed in the other modes. In the egocentric mode it took longer to develop an adequate IR than in the other modes. No effect of presentation speed was found.In the third experiment the effects of two variables (number of corners, number of crossings) possibly related to a network's complexity were investigated. The results did not make a wholly clear picture and pointed to the necessity of further experimentation. 相似文献
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