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921.
Albert R. Jonsen 《Theoretical medicine and bioethics》1986,7(1):65-74
For the last century, moral philosophy has stressed theory for the analysis of moral argument and concepts. In the last decade, interest in the ethical issues of health care has stimulated attention to cases and particular instances. This has revealed the gap between ethical theory and practice. This article reviews the history and method of casuistry which for many centuries provided an approach to practical ethics. Its strengths and weaknesses are noted and its potential for contemporary use explored. 相似文献
922.
923.
Attention, Perception, & Psychophysics - Speech perception abilities are modified by linguistic experience to maximize sensitivity to acoustic contrasts that are important for one’s... 相似文献
924.
Alternate monocular and binocular exposure to complementary stimulation can yield opposite but coexisting aftereffects that are contingent on whether the test display is viewed with one eye or two eyes. The motion aftereffect was studied by adapting each eye separately to a contracting spiral and both eyes together to an expanding spiral. The stationary test spiral subsequently appeared to be expanding when viewed monocularly, but to be contracting when it was seen with both eyes open. With respect to the McCollough effect, after monocular exposure to red-vertical and green-horizontal gratings and binocular exposure to red-horizontal and green-vertical gratings, the appearance of the color of the test gratings when viewed with one eye was different from that when viewed with both eyes. Opposite, coexisting aftereffects induced by complementary stimulation can be interpreted as evidence that there are unique binocular aspects to visual function. 相似文献
925.
Although current theories of memory emphasize the fact that learning is an active process, there is little consensus on the role of active learning. This paper attempts to provide a more precise characterization of active learning in the acquisition of computer skills. The analysis of verbal protocols suggests that active learning varies on at least two dimensions: schema orientation and learning strategy. Schema orientation refers to the type of information the learner is acquiring and varies from relational information to procedural information. Learning strategy describes how the information is acquired. Some people prefer to be internally driven and form their own plans for learning. Others are externally driven and allow the instructional materials to guide their learning. These differences need to be taken into account in describing learning and in designing instructional materials. 相似文献
926.
927.
An analysis of some sensitizing agents in the pathogenesis of stress-induced gastric erosive disease
B. H. Natelson M. Ferrara-Ryan D. Creighton J. Yavorsky G. Curtis W. N. Tapp 《Integrative psychological & behavioral science》1984,19(4):195-199
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males. 相似文献
928.
Recent studies have begun to test certain fundamental assumptions underlying popular models of feature perception. This research is continued here. It was discovered that every basic assumption that was open to test in the present study was disconfirmed. However, several new characteristics of line and curve feature perception were discovered: (1) Feature perception sensitivity was inversely related to the number of features present in a stimulus pattern, and the decision criteria for reporting a feature decreased with the number of features contained in a pattern; (2) the decrements in sensitivity reported in (1) were greater for features lying inside a pattern than for those on the exterior; and (3) feature perception sensitivity actually improved if another feature was known to be correctly perceived during the same trial. Likewise, feature sensitivity decreased if another feature was missed on any trial. At the present time, a system that first extracts global and then local (more detailed) featural information provides a basis that qualitatively accounts for our findings and is also compatible with several other studies in the literature. 相似文献
929.
This paper provides some initial normative and validity data on the Social Avoidance and Distress (SAD) and the Fear of Negative Evaluation (FNE) scales for junior high school students. Findings indicated: the level of social-evaluative anxiety does not significantly vary during the junior high school years or between sexes, junior high school students report similar levels of FNE to college students but less SAD, a significant positive correlation between treatment subjects' SAD scores and peer sociometric ratings of social-evaluative anxiety, and subjects treated for social anxiety reported significantly less SAD and FNE at follow-up assessment. Recommendations for future research and clinical use of the SAD and FNE are offered. 相似文献
930.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents. 相似文献