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141.
The long-term effect of transplanting embryonic frontal cortex into a unilateral frontal cortex lesion has been studied in adult rats. Before surgery, activity in an open field, muscular strength of both forelimbs, and performance in a paw-reaching-for-food task were scored in 26 rats. In 21 animals a unilateral cortex lesion was then made in the forelimb motor area of the hemisphere contralateral to the preferred paw in the paw-reaching-for-food task, while the other 5 animals were sham-operated. On retesting, the lesion animals changed the preferred paw. A solid homotopic transplant of embryonic tissue (embryonic day 17) was then placed in the lesion cavity in 11 of the lesion rats. Three months later neither lesion alone nor lesion plus transplantation affected open field behavior and muscular strength, but the lesion permanently affected performance in the paw-reaching-for-food task, as shown by a change of preferred paw and a functional deficit in the paw contralateral to the lesion. Transplantation ameliorated the deficits caused by the lesion, but this was only evident when animals were forced to reach with the paw contralateral to the lesion plus transplant. The behavioral results were independent of the size of the lesion and graft. Connections between graft and host tissue were studied by means of the fluorescent tracer 1,1'-dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate (DiI). A dense array of labeled fibers was found in the host cortex adjacent to the transplant. The results suggest that functional recovery depends on grafting but is only evident when the animal is obliged to use the affected limb.  相似文献   
142.
This article reports on the development and teaching of compulsory courses on ethics and engineering at Delft University of Technology (DUT). Attention is paid to the teaching goals, the educational setup and methods, the contents of the courses, involvement of staff from engineering schools, experiences to date, and challenges for the future. The choices made with respect to the development and teaching of the courses are placed within the European and Dutch context and are compared and contrasted with the American situation and experiences. Previous versions of this article were presented at the meeting of the SEFI Working Group on Engineering Ethics in Rzeszow, Poland, April 29–May 1, 1999 and at the SEFI Annual Conference in Zurich, Switzerland, September 1–3, 1999.  相似文献   
143.
In this editorial contribution, two issues relevant to the question, what should be at the top of the research agenda for ethics and technology, are identified and discussed. Firstly: can, and do, engineers make a difference to the degree to which technology leads to morally desirable outcomes? What role does professional autonomy play here, and what are its limits? And secondly, what should be the scope of engineers' responsibility; that is to say, on which issues are they, as engineers, morally obliged to reflect? The research agendas proposed by the authors contributing to this special section, implicitly, give different answers to these questions. We suggest that an explicit discussion of these issues would greatly help in constructing a common research agenda.  相似文献   
144.
Despite the major advances in the development of treatments for bulimia nervosa, drop-outs and a lack of engagement in treatment, continue to be problems. Recent studies suggest that the transtheoretical model of change may be applicable to bulimia nervosa. The aim of this study was to examine the roles of readiness to change and therapeutic alliance in determining engagement and outcome in the first phase of treatment. One hundred and twenty five consecutive female patients meeting DSM-IV criteria for bulimia nervosa took part in a randomised controlled treatment trial. The first phase of the sequential treatment compared four sessions of either cognitive behavioural therapy (CBT) or motivational enhancement therapy (MET) in engaging patients in treatment and reducing symptoms. Patients in the action stage showed greater improvement in symptoms of binge eating than did patients in the contemplation stage. Higher pretreatment scores on action were also related to the development of a better therapeutic alliance (as perceived by patients) after four weeks. However, pretreatment stage of change did not predict who dropped out of treatment. There were no differences between MET and CBT in terms of reducing bulimic symptoms or in terms of developing a therapeutic alliance or increasing readiness to change. The results suggest that the transtheoretical model of change may have some validity in the treatment of bulimia nervosa although current measures of readiness to change may require modification. Overall, readiness to change is more strongly related to improvement and the development of a therapeutic alliance than the specific type of treatment.  相似文献   
145.
Both cross-sectional and longitudinal studies in the United States have shown consistent changes between college age and middle adulthood. There appear to be declines in 3 of the 5 major factors of personality--Neuroticism, Extraversion, and Openness--and increases in Agreeableness and Conscientiousness. To examine cross-cultural generalizability of these findings, translations of the Revised NEO Personality Inventory were administered to samples in Germany, Italy, Portugal, Croatia, and South Korea (N = 7,363). Similar patterns of age differences were seen in each country, for both men and women. Common trends were also seen for the more specific traits that define the major factors. Because these nations differ substantially in culture and recent history, results suggest the hypothesis that these are universal maturational changes in adult personality.  相似文献   
146.
Further evidence for feature correlations in semantic memory.   总被引:4,自引:0,他引:4  
The role of feature correlations in semantic memory is a central issue in conceptual representation. In two versions of the feature verification task, participants were faster to verify that a feature (< is juicy >) is part of a concept (grapefruit) if it is strongly rather than weakly intercorrelated with the other features of that concept. Contrasting interactions between feature correlations and SOA were found when the concept versus the feature was presented first. An attractor network model of word meaning that naturally learns and uses feature correlations predicted those interactions. This research provides further evidence that semantic memory includes implicitly learned statistical knowledge of feature relationships, in contrast to theories such as spreading activation networks, in which feature correlations play no role.  相似文献   
147.
The ESPbase provides a tool for storing symbols and icons along with information about their characteristics. Information about a wide range of symbol characteristics is included on the database to facilitate the selection of symbol sets for research and design. The database includes information about the graphical characteristics and functions of symbols. It also includes ratings of symbol concreteness, complexity, familiarity, and meaningfulness. Symbols and icons can be accessed on the basis of each of these characteristics or any combination of characteristics. This makes it easier to select symbols on the basis of usability and design requirements. It also means that symbols can be easily selected for research while controlling their characteristics on a number of dimensions.  相似文献   
148.
149.
Measures of intention usually leave substantial proportions of the variance in behavior unexplained. It has been suggested that improved behavioral prediction could be achieved by identifying postdecisional cognitive processes capable of distinguishing between intenders who do act and those do not act. Condom-related self-report measures of postdecisional cognitive processes were developed and tested in a cross-sectional questionnaire study involving 447 heterosexual students. A discriminant function composed of postdecisional measures was found to significantly distinguish between intenders who reported use and non-use and to correctly classify 80% of intenders. The results indicate that measures of the relative importance of competing intentions, prior planning of specific preparatory actions, and action-specific self-efficacy may enhance the prediction of condom use among intenders.  相似文献   
150.
A TASTE FOR HUME     
Patricia de  Martelaere 《Ratio》1989,2(2):122-137
  相似文献   
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