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991.
While many studies have attempted to produce hypertension through the use of various environmental Stressors, few have succeeded in producing chronic elevations in blood pressure beyond levels considered to be borderline hypertensive (140–160 mm Hg systolic). The problem with most studies stems from the use of genetically normotensive animals and the selection of Stressors to which animals readily adapt. A new approach is suggested, which recognizes the role of genetics in human essential hypertension. Animals with one hypertensive parent do not develop spontaneous hypertension but show a more sensitive cardiovascular response to environmental Stressors than animals with normotensive parents. Preliminary studies revealed that animals with a mixed genetic history of hypertension develop spontaneous borderline hypertension. When subjected to shock-shock conflict, these borderline hypertensive rats (BHR) developed permanent hypertension that failed to abate even after a ten-week, shock-free recovery period. The hypertension was accompanied by elevated heart weight to body weight ratios and by significant cardiac pathology. Subsequent work has demonstrated that these animals also become hypertensive when fed a high-sodium diet. Finally, in a series of exercise studies, we found that BHRs subjected to a shock stressor were protected against stress-induced hypertension if they exercised daily. The potential of this model for studies of the mechanisms by which environmental variables produce permanent hypertension is discussed.  相似文献   
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993.
Sternheim and Boynton’s (1966) continuous judgmental color-naming technique was used to assess the elemental nature of achromatic colors. Results from three subjects indicate that the names “black” and “white” are necessary and sufficient to describe achromatic test lights associated with the name “gray.” On the basis of the criteria that establishes a color as elemental, black and white were confirmed as elemental, whereas gray was not. These findings support the assumption of various opponent processing models that there are only two elemental achromatic sensations. In addition, the results support Hering’s (1920) view that black and white differ from the paired-chromatic opponent colors in that they are not mutually exclusive.  相似文献   
994.
Two experiments investigated infants’ sensitivity to familiar size as information for the distances of objects with which they had had only brief experience. Each experiment had two phases: a familiarization phase and a test phase. During the familiarization phase, the infant played with a pair of different-sized objects for 10 min. During the test phase, a pair of objects, identical to those seen in the familiarization phase but now equal in size, were presented to the infant at a fixed distance under monocular or binocular viewing conditions. In the test phase of Experiment 1, 7-month-old infants viewing the objects monocularly showed a significant preference to reach for the object that resembled the smaller object in the familiarization phase. Seven-month-old infants in the binocular viewing condition reached equally to the two test phase objects. These results indicate that, in the monocular condition, the 7-month-olds used knowledge about the objects’ sizes, acquired during the familiarization phase, to perceive distance from the test objects’ visual angles, and that they reached preferentially for the apparently nearer object. The lack of a reaching preference in the binocular condition rules out interpretations of the results not based on the objects’ perceived distances. The results, therefore, indicate that 7-month-old infants can use memory to mediate spatial perception. The implications of this finding for the debate between direct and indirect theories of visual perception are discussed. In the test phase of Experiment 2,5-month-old infants viewing the objects monocularly showed no reaching preference. These infants, therefore, showed no evidence of sensitivity to familiar size as distance information.  相似文献   
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998.
This paper deals with imposturous tendencies as ubiquitous and heterogeneous. They may enter into neurotic conflict and compromise, and also reflect an ego function disturbance involving multiple, shifting identities and subsequent problems in the subjective sense of reality of the self and objects. Imposture in a person undergoing analysis is, however, not only a function of individual character and psychopathology; it is also a function of certain inevitable requirements of the analytic situation which constitute a "pull" for its emergence. Vulnerable individuals will respond to this pull in revealing ways. Three case summaries illustrate the spectrum of imposturous tendencies.  相似文献   
999.
A small informal poll of local colleagues revealed that despite their interest in the subject, many had doubts about the possibility of analyzing persons aged sixty or over successfully. Their specific questions are collated and are offered as a sample of the questions in the minds of many analysts everywhere. Selected material from the ongoing analysis of a sixty-four-year-old patient is presented that bears on some of the questions raised. In addition, changes in the patient are noted. These are discussed in terms of changes in function, which are equated with structural change. The major thrust of the paper is that development continues throughout the life course, and that the criteria for analyzability remain constant. The chronological age of the adult by itself is not an indicator of eligibility or of suitability for psychoanalysis.  相似文献   
1000.
An assessment of the Hasher and Zacks (1979) conceptualization of the automatic nature of the acquisition of spatial location information was made in the context of manipulations of subjects' intention to learn and mood state. The Velten (1968) mood induction procedure was used to establish depressed and nondepressed subjects. Half of each group was then presented with a matrix of geometric forms under instructions to learn the location of the forms (intentional) or to evaluate the pleasantness of the array (incidental). Subsequent tests of spatial location performance found no differences as a function of subjects' mood state, but did find a strong effect for instructional condition. The superior performance of the intentional subjects raises questions about the automatic nature of the encoding of spatial location.  相似文献   
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