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991.
Regina Kenen Ann C. M. Smith Carolee Watkins Carol Zuber-Pittore 《Journal of genetic counseling》2000,9(3):203-217
We conducted an exploratory, qualitative study investigating the factors influencing the use of genetic counseling and prenatal genetic testing for two groups: pregnant women 35 years of age and over (AMA) at the time of delivery and pregnant women with an abnormal maternal serum triple screen (MSAFP3). The convenience sample consisted of 25 semistructured interviews of women/couples and 50 observations of genetic counseling sessions. Worry turned out to be the most important variable influencing decision making about prenatal genetic testing and was greater in the MSAFP3 group than in the AMA group. The women in the AMA group appeared to assign the risk of having a child with Down syndrome to their age category rather than to themselves individually, whereas, the risk perception for women with an abnormal MSAFP3 appeared to have shifted from a general population risk for pregnant women to an individual, personal risk. There was a general lack of understanding and also more misinformation about the MSAFP3 screen compared to amniocentesis. Women in both groups were torn between fear of an invasive test and worry about the health of their fetus for the rest of their pregnancy if they did not undergo amniocentesis. 相似文献
992.
Melissa Ann Stormont Sandra Covington Smith Timothy J. Lewis 《Journal of Behavioral Education》2007,16(3):280-290
Although research has clearly supported the use of school-wide positive behavior support (PBS) in elementary school settings,
data-based research has not been conducted to support program-wide PBS in early childhood settings. The purpose of this study
was to specifically support teachers’ use of universal features of program-wide PBS and to determine whether increases in
the use of positive teacher behaviors, including precorrection and praise, were functionally related to decreases in students’
problem behavior. Using a multiple baseline design, three teachers were introduced to an intervention to increase their use
of precorrections and specific behavioral praise statements. A relationship was established between the three teachers’ use
of key features of program-wide PBS and the reduction of students’ problem behavior in a small group setting. However, findings
should be viewed as tentative and future research should explore the relative influence of each of the intervention components
on preschool students’ behavior. 相似文献
993.
We review and relate two literatures on the development of attention in children: one concerning flexible attention switching and the other concerning selective attention. The first is a growing literature on preschool children’s performances in an attention‐switching task indicating that children become more flexible in their attentional control during the preschool years. The second literature encompasses a large and robust set of phenomena for the same developmental period that indicates a protracted course of development for selective attention in children. We ask whether developmental changes in processes of selective attention may contribute to more flexible attention switching. We consider the two sets of phenomena with respect to this question and propose an empirical agenda for their joint study that may lead ultimately to a unified account of the development of selective attention and attention switching. 相似文献
994.
995.
The development of a secondary reinforcer as a result of associating a neutral stimulus (buzzer) with intravenous (IV) doses of morphine was studied in rats. Secondary reinforcement developed in the absence of physical dependence and followed the association of the stimulus with either response-contingent or non-contingent injections of morphine. Strength of the conditioned reinforcer, measured in terms of responding on a lever for the stimulus plus infusion of saline solution, was proportional to the unit dosage of morphine employed in pairings of buzzer and drug. When extinction of the lever-press response for IV morphine was conducted (by substituting saline for morphine solution) in the absence of the conditioned reinforcing stimulus, it was seen later that the stimulus could still elicit lever responses, until it too had been present for a sufficient interval of non-reinforced responding. Similarly, extinction of the response for morphine by blocking its action with naloxone in the absence of the stimulus did not eliminate the conditioned reinforcement. Another study showed that a passive, subcutaneous (SC) dose of morphine served to maintain lever-pressing on a contingency of buzzer plus sahne infusion. Furthermore, the stimuli resulting from the presence of morphine (after a SC injection) were able to reinstate the lever-responding with only the buzzer-saline contingency when such responses had previously been extinguished. Moreover, it was shown thatd-amphetamine could restore responding under the same conditions, and that morphine could also do so for rats in which the primary reinforcer had beend-amphetamine. It is suggested that animal data such as these show that procedures designed for the elimination of human drug-taking behavior must take into account secondary reinforcers as well as the primary reinforcer(s). 相似文献
996.
Theories of the psychological refractory period 总被引:5,自引:0,他引:5
M C Smith 《Psychological bulletin》1967,67(3):202-213
997.
998.
Previous research has demonstrated that hemispheric asymmetries for conscious visual perception do not lead to asymmetries for unconscious visual perception. These studies utilized emotionally neutral items as stimuli. The current research utilized both emotionally negative and neutral stimuli to assess hemispheric differences for conscious and unconscious visual perception. Conscious perception was measured using a subjective measure of awareness reported by participants on each trial. Unconscious perception was measured by an "exclusion task," a form of word-stem-completion task. Consistent with predictions, negative stimuli were consciously perceived most often when presented to the right hemisphere. Negative stimuli presented to the right hemisphere showed no evidence of unconscious perception, suggesting that the hemispheric asymmetry for the conscious perception of negative information occurs at the expense of unconscious perception. 相似文献
999.
1000.
Chong Un Choe Smith 《Theoretical medicine and bioethics》2014,35(2):175-185
A common assumption in the selection of nonhuman animal subjects for research and the approval of research is that, if the risks of a procedure are too great for humans, and if there is a so-called scientific necessity, then it is permissible to use nonhuman animal subjects. I reject the common assumption as neglecting the central ethical issue of the permissibility of using nonhuman animal subjects and as being inconsistent with the principle of justice used in human subjects research ethics. This principle requires that certain classes of individuals not be subjected to a disproportionate share of the burdens or risks of research. I argue for an extension of this principle to nonhuman animal research and show that a prima facie violation of the principle occurs because nonhuman animals bear an overwhelmingly disproportionate share of the risks of research without sufficient justification or reciprocal benefit. 相似文献