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We present four cases of Prader-Willi syndrome. Two of them have an abnormality of a chromosome 15, the other both show different chromosomal abnormalities. Translocations or deletions were found recently in the bands 15q11/12 in about 60% of the cases of Prader-Willi syndrome. The consequences for diagnosis, symptomatology and genetic counselling of the syndrome are discussed.  相似文献   
826.
The cross-correlation method was used to measure interhemisphere phase differences over four areas of the brain in 22 healthy children aged between 7 and 10 years. Apart from defining normal values, the authors describe age-dependent characteristics and changes that take place as a result of mental stress.  相似文献   
827.
The emergence of oedipal object relations is a crucial stage in the development toward individuated adult mentation, distinguished from early stages of psychic life which are transindividual (as in Kohut's "selfobject transference"). The latter continue to function as deep layers of individual psychic life; but the development of oedipal/postoedipal object relations, and advanced psychic structure and functioning based on it, represents a norm in psychoanalytic psychology and therapy. The poet John Keats's ideas about the formation of the individual "soul" (identity as an individual) by the intervention of "circumstances" are cited to illustrate this aspect of the oedipus complex.  相似文献   
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Gender differences across age in motor performance a meta-analysis   总被引:3,自引:0,他引:3  
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829.
Thomas R. Alley 《Synthese》1985,65(3):411-444
The concept of an ecological niche (econiche) has been used in a variety of ways, some of which are incompatible with a relational or functional interpretation of the term. This essay seeks to standardize usage by limiting the concept to functional relations between organisms and their surroundings, and to revise the concept to include epistemic relations. For most organisms, epistemics are a vital aspect of their functional relationships to their surroundings and, hence, a major determinant of their econiche. Rejecting the traditional dualism of organism and environment, an econiche is defined as the reciprocal (dual) of a functionally specified class of organisms (FSTU). From this perspective, an econiche necessarily implies a certain type of organism, and a class of functionally similar organisms implies a special econiche.The econiche concept is also discussed in relation to other ecological terms that reflect the distributional patterns of organisms, such as habitat, and the concept of an empty niche is criticized.Special thanks are due to Michael Turvery for his part in many stimulating discussions of some of the problems and concepts addressed in this paper. I am also grateful to him and to Claudia Carello, Tim Johnston, Bill Mace, Bernard Patten, Ed Reed, Robert E. Shaw, Bill Warren, and an anonymous reviewer for their comments on earlier drafts of this paper.  相似文献   
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