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Visual acuity for the detection of gratings at four orientations was measured for groups of ten boys and ten girls aged five to seven years, from the following four populations: Scots in Glasgow, Pakistanis in Glasgow, Gaels in Stornoway (Outer Hebrides) and East Anglians in Littleport (Cambridgeshire fenlands). The Glaswegians, both Scottish and Pakistani, showed the normal pattern of anisotropy, with poorest acuity for oblique orientations; the East Anglians showed no significant anisotropy; while the Gaels were unusual in showing poorest horizontal acuity. A group of fourteen Pakistani children in Stornoway differed slightly from a matched group of Gaels. The group differences bore little relation to the visual environments, and were probably due to genetic or cultural factors. The relatively poor horizontal acuity of the Gaels was not correlated with astigmatism. Sex differences were also found, with the boys showing higher mean acuity and a higher ratio between vertical and oblique acuity.  相似文献   
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The purpose of this study was to determine the effects of Type A behavior and family history of hypertension on cardiovascular reactivity to mental stress in a group of employed black women. Measures of heart rate and of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken at rest, during a mental arithmetic task, and during the Type A Structured Interview (SI). Results indicated that the Type A behavior pattern was associated with SBP and DBP hyperresponsivity during the SI but not during mental arithmetic. Additionally, certain speech components of the Type A pattern, as well as features of the potential-for-hostility component, were also related to cardiovascular responses during the SI. Family history of hypertension did not influence the cardiovascular parameters either alone or in combination with Type A behavior. The results suggest that many of the cardiovascular response characteristics of the Type A pattern that have been observed in predominantly white samples also hold true for blacks. Replication of these findings with other subgroups of blacks, such as young females and middle-aged males, will help document the generality of these findings within the black population.  相似文献   
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Another look at Bare Particulars   总被引:1,自引:0,他引:1  
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MMPI profiles of female adolescents hospitalized on a general pediatrics floor following a suicide attempt were compared to a control group of medically hospitalized, female adolescents referred for psychiatric evaluation. The suicide attempters had only a lower score on the K scale when compared to the control group. Results do not suggest that a single MMPI profile differentiates suicide attempters from a comparison group of adolescents with emotional difficulties. Implications of these findings are discussed.  相似文献   
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Two formats of the Multidimensional Health Locus of Control (MHLC) Scales were administered to 54 college students. Each subject completed the MHLC Scales in the standard 6-level response format (ranging from strongly disagree to strongly agree) and in a revised 2-level format (ranging from disagree to agree). Comparisons of internal consistency measures, principal components, and classification of subjects into groups indicate that the 2-level response format yields comparable data to those obtained with the 6-level format, particularly when classification of subjects is the goal.  相似文献   
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