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951.
Li FP 《Ethics & behavior》1995,5(2):193-196
Case vignette: sharing unanticipated genetic information. The Questor family has experienced an unusual number of malignancies in the past two generations and has been advised by an oncologist that the p53 oncogene known as Li-Fraumeni Syndrome may be present in the family genome. The option of predictive genetic testing has been raised and several branches of the family have chosen to undergo screening to determine whether they are at risk for cancer because of the gene. Roger and Liz Questor have arranged for screening of themselves and their three children, ages 12, 10, and 7. The couple has, by all appearances, been happily married for 14 years. None of the family members are found to carry the oncogene; however, the geneticist conducting the analyses has made an interesting incidental discovery. The 10-year-old child is not the biological progeny of Roger Questor. Although the 12- and 7-year-olds are clearly the biological children of the couple, it is evident that the 10-year-old born to Liz Questor was fathered by a person other than Roger. What are the ethical obligations of the geneticist with respect to any sharing or disclosure of the information that has been discovered incidentally? What course of action, if any, do you recommend?  相似文献   
952.
Extinguishing a fixation point shortly before, or concurrently with, the onset of a peripheral visual target reduces the latency of saccades to that target. Saslow (1967) hypothesized that thisgap effect might occur because fixation point offsets reduce the incidence of corrective microsaccades with an associated saccadic refractory period. In the present study, a robust gap effect was obtained. However, using a Purkinje image eyetracker with 1 arcmin of resolution, we found that fixation point offsets had no effect on the occurrence of microsaccades and that the occurrence of microsaccades had no impact on the magnitude of the gap effect. Microsaccades therefore do not appear to play any part in the production of the gap effect.  相似文献   
953.
Cortisol can be used to indicate stress level as well as to monitor certain disease states. Although cortisol can be sampled from blood and urine, saliva sampling has decided advantages. Unfortunately, whole saliva contains a number of substances that can metabolize or bind with cortisol, potentially confounding analysis and quantitation. We introduce a semipermeable pouch that accumulates a contaminant-free salivary ultrafiltrate, thereby overcoming a number of the problems encountered with whole saliva. In three studies, we demonstrate accuracy and utility of the device for cortisol determination: (1) in an artificial medium, 60%–77% of the cortisol was recovered in the ultrafiltrate; (2) in vivo, ultrafiltrate cortisol correlated highly with whole-saliva cortisol collected under ideal conditions; and (3) ultrafiltrate cortisol evinced positive relationships with depression and cigarette use, consistent with studies in the literature. We conclude that this device and saliva-filtering technologies in general are useful in applications requiring quantitation of cortisol.  相似文献   
954.
A technique is described for rapidly collecting responses in auditory-localization experiments. Subjects indicate the perceived direction of the sound by pointing at a 20-cm-diam spherical model. In Experiment 1, the subjects judged the direction of a broadband signal, which could originate from any of 239 directions ranging through 360° of azimuth and between ?45° and +90° of elevation. Using this technique, the subjects responded 2–8 times more rapidly than previous subjects who used either a verbal-reporting technique or a head-pointing technique. Localization judgments were as accurate as they had been with verbal reports, but were not as accurate as judgments collected using the head-pointing technique. In Experiment 2, the signal was turned off and the experimenter read the spherical coordinates of the signal location to the subjects. The subjects pointed to these coordinates more accurately than they had judged the direction of the sounds in Experiment 1, suggesting that the response technique had not been the limiting factor in that experiment. Circumstances relevant to the choice of response techniques for auditory-localization experiments are discussed.  相似文献   
955.
The inhibition of return of visual attention based on stimulus color was examined in three experiments. In the first experiment, a discrete trial paradigm showed that subjects were slower to detect a color patch if the color matched that of a patch presented earlier in the same location. Experiment 2 showed that the inhibition only occurs if a neutral, nontarget distractor color is presented between presentation of the initial color cue and the subsequent target patch—explaining the previous failures to detect the phenomenon. Experiment 3 extended the results to a different combination of colors. Taken together, the results have important implications for the processing of stimulus attributes such as spatial location and color, and for the conditions necessary for producing inhibition of return.  相似文献   
956.
Individual differences in selection of intensity of angry interactions and physiological and self-reported responses to interadult anger were examined in preschoolers (N=34). Children watched two videotaped angry interactions between adults, while their heart rates and skin conductance responses and levels were monitored; then they were interviewed. Before the second argument, children were given the perceived choice of watching an intense or mild angry exchange. Individual differences in responding to the angry interactions were found. Both (a) children with relatively higher externalizing behavior problems and (b) boys who chose to watch intense anger had lower tonic heart rates; 80% of boys with externalizing problems chose to watch intense anger. Further, children who chose to watch intense anger (a) exhibited lower declines in heart rates upon the presentation of the argument, (b) perceived the actors as more angry, and (c) reported lower amounts of distress during the argument than those who chose mild anger.  相似文献   
957.
958.
Attentional biases for threat stimuli were assessed in high and low trait anxious subjects (n = 66) using a probe detection task. To examine the effects of trait anxiety and situational stressors, each subject was tested three times: Under no stress, laboratory-induced stress, and examination-induced stress. To evaluate the role of awareness, half the word stimuli were presented very briefly (14 msec) and masked, and the other half were presented for 500 msec without a mask. Results showed that high trait anxious subjects under exam stress showed an attentional bias towards unmasked threat stimuli compared with low trait subjects. This effect was not found under lab-induced stress, suggesting that the attentional bias for unmasked threat in high trait subjects may be a function of a prolonged stressor, rather than a transient increase in state anxiety. The results from the masked exposure condition were not predicted; high trait anxious subjects shifted attention towards the spatial location of threat words despite lack of awareness of their lexical content, but this bias was only apparent in the no-stress condition. The results are discussed in relation to recent cognitive theories of anxiety.  相似文献   
959.
Summary In a recent paper analysing the Simon effect, Hasbroucq and Guiard (1991) concluded that stimulus congruence, a correspondence relationship between stimulus components, accounts for the Simon effect and explains its reversal in the Hedge and Marsh experiment (1975). We contend that their definition of stimulus congruence is applied inconsistently, which invalidates their conclusion. It is argued here that the effect of display-control arrangement correspondence (Simon, Sly, & Vilapakkam, 1981) is an alternative account that fits the presented data better. In a second experiment, Hasbroucq and Guiard (1991) claimed to have invalidated the suggestion that display-control arrangement correspondence could be considered to be an alternative account of the findings in their Experiment 1. However, we assert that the type of display-control arrangement employed in their second experiment was so unpredictable that no effect of display-control arrangement correspondence could occur.  相似文献   
960.
Indirect modes of aggression among women of Buenos Aires,Argentina   总被引:1,自引:0,他引:1  
This study utilizes the construct indirect aggression to investigate aggressive behavior among middle class Argentine women and men by administering an attitude and self-report survey to 95 inhabitants of Buenos Aires and by analyzing ethnographic interviews and observations conducted over a nine month period in 1992. An examination of sex roles in Argentina, including machismo and marianismo, provide a cultural context for interpreting aggression. Factor analyses revealed the presence of indirect aggression (e.g., social manipulation, gossip, exclusion) in addition to verbal and physical aggression. Survey and ethnographic findings converge in suggesting that women employ more indirect aggression than men, while men utilize more physical aggression. While competition and aggression are salient elements of social life for both sexes, women and men tend to favor different approaches. The findings are compared with the literature on female aggression from other cultural settings. We conclude that cultural and evolutionary perspectives elucidate aspects of female aggression.We would like to thank the Ford Foundation for providing the financial support to make this research possible. We would also like to thank Patricia de Gyldenfeldt and Debbie Bandura for their endless contributions with translations, ideas, and help in general. Finally, we would like to thank Eckerd College, la Universidad del Salvador, and Michael Hobson for their base of support, all those in Argentina, especially Agueda, Andrea, Carmen, Cecilia, Claudio, Daniela, Heidi, Ingrid, Javier, Julio, María, Mariela, Roberto, and Victor, who offered their enthusiastic assistance and ideas, and Victoria Burbank, Ayala Gabriel, and the anonymous reviewer for their helpful suggestions.  相似文献   
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