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281.
The use of experimental animals, mostly rodents, in biomedical research and especially in oncology and immunology should be acknowledged with respect, recognizing the contribution of animal experimentation in the fascinating scientific progress in these disciplines of research. It is an obligation of the investigator to justify the scientific and ethical aspects of each study requiring the use of animals. The international guiding principles for using animals in biomedical research are well defined and have been distributed worldwide by the International Council for Laboratory Animal Science (ICLAS) since 1956, when this Organization was founded. In Poland the ICLAS philosophy and principles are highly respected and were implemented firstly by the members of the Commission on Biology of Experimental Animals appointed in 1962 by the Department of Medical Science of the Polish Academy of Science in Warsaw. Animal Protection Acts, first proclaimed in 1928 were gradually modified and improved. Actual legislation (enacted in 1997, 2003 and 2005) is consistent with EU Directives (86/609/EEC) and follows the internationally recommended principles that include ICLAS guidelines concerning animal welfare and care condition in biomedical research. The problem of “alternative methods” is briefly discussed. Dr. Donald Boisvert, CCAC — Canadian Council on Animal Care A lecture on the subject of this paper was presented at the 6th International Bioethics Conference entitled ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005. The author is the National Representative of Polish Academy of Science to the International Council for Laboratory Animal Science (ICLAS) and a Member of the ICLAS Governing Board.  相似文献   
282.
283.
In this article, I argue that it is wrong to conduct any experiment on a nonhuman which we would regard as immoral were it to be conducted on a human, because such experimentation violates the basic moral rights of sentient beings. After distinguishing the rights approach from the utilitarian approach, I delineate basic concepts. I then raise the classic “argument from marginal cases” against those who support experimentation on nonhumans but not on humans. After next replying to six important objections against that argument, I contend that moral agents are logically required to accord basic moral rights to every sentient being. I conclude by providing criteria for distinguishing ethical from unethical experimentation.  相似文献   
284.
A dynamic 3-D virtual environment was constructed for humans as an open-field analogue of Blaisdell and Cook's (2005) pigeon foraging task to determine if humans, like pigeons, were capable of integrating separate spatial maps. Participants used keyboard keys and a mouse to search for a hidden goal in a 4×4 grid of raised cups. During Phase 1 training, a goal was consistently located between two landmarks (Map 1: blue T and red L). During Phase 2 training, a goal was consistently located down and left of a single landmark (Map 2: blue T). Transfer trials were then conducted in which participants were required to make choices in the presence of the red L alone. Cup choices during transfer assessed participants’ strategies: association (from Map 1), generalization (from Map 2), or integration (combining Map 1 and 2). During transfer, cup choices increased to a location which suggested an integration strategy and was consistent with results obtained with pigeons. However, additional analyses of the human data suggested participants initially used a generalization strategy followed by a progressive shift in search behavior away from the red L. This shift in search behavior during transfer was responsible for the changes in cup choices across transfer trials and was confirmed by a control condition. These new analyses offer an alternative explanation to the spatial integration account proposed for pigeons.Electronic Supplementary Material Supplementary material is available for this article at  相似文献   
285.
This article introduces a novel approach for the analysis of the dynamics of reasoning processes and explores its applicability for the reasoning pattern called reasoning by assumption. More specifically, for a case study in the domain of a Master Mind game, it is shown how empirical human reasoning traces can be formalized and automatically analyzed against dynamic properties they fulfill. To this end, for the pattern of reasoning by assumption a variety of dynamic properties have been specified, some of which are considered characteristic for the reasoning pattern, whereas some other properties can be used to discriminate among different approaches to the reasoning. These properties have been automatically checked for the traces acquired in experiments undertaken. The approach turned out to be beneficial from two perspectives. First, checking characteristic properties contributes to the empirical validation of a theory on reasoning by assumption. Second, checking discriminating properties allows the analyst to identify different classes of human reasoners.  相似文献   
286.
The objective of this study is to simulate the dynamic response of the human body within a rear-end impacted vehicle. A nonlinear mathematical model of a human body and a restraint system has been formulated. The model consists of connected rigid bodies representing the torso and limbs of the human frame. Nonlinear springs and dampers are used at the connection joints to represent human anatomical characteristics and limits imposed by muscles, ligaments, and soft tissue. Equations of motion are written for this model by using Kane's equation and multibody dynamics analysis procedures developed by Huston. The equations are integrated numerically for a number of specific cases where experimental data are available. Results show excellent agreement between the model and the experiments. The results of several accident simulations are also presented.  相似文献   
287.
Questionnaires were completed by sixth-grade students and their parents in order to assess differences between children of alcoholics (COAs) and their peers, as well as the relations between family environment and children's experimentation with alcohol, drugs, and tobacco. Social competence and problematic behavior were also explored. The best predictors of early experimentation with alcohol, drugs, and tobacco were the experience of negative life events, family conflict, and lack of family cohesion, but not COA status per se. Differences were found between COAs and non-COAs in respect to family structure, parent education levels, and family environment. COAs were found to be significantly more likely than their peers to experiment with tobacco, but not alcohol or drugs. They also had a tendency to engage more frequently in delinquent behavior. Recommendations for future research and implications for preventive activities are discussed.  相似文献   
288.
A research study to identify the priori gene mutation in a family with familial Creutzfeldt-Jakob disease (FCJD) evolved into presymptomatic diagnostic testing. Our experience with one case raises concerns regarding similar studies that will ensue as a result of the Human Genome Project. Technological advances in human molecular genetics make it difficult for Institutional Review Boards (IRB) to adequately evaluate proposed studies. Additionally, changes in the implications of the study may occur after initial IRB approval, due to technological progress. While FCJD, like Huntington's disease (HD), has adult onset and causes progressive dementia and ataxia, protocols established for presymptomatic testing of HD were not included in the FCJD study design. It is thus recommended that IRB committees include a genetics professional and that IRB-approved research studies be reevaluated on a regular basis to monitor the impact that technological advances may have on participating human subjects.  相似文献   
289.
Children 4 to 6 years of age were exposed to repetitions of a six-tone melody, then tested for their detection of transformations that either preserved or changed the contour of the standard melody. Discrimination performance was examined as a function of contour condition, magnitude of contour change, rate of presentation, and the presence of novel frequencies. Performance was superior for transformations that changed contour compared to those that did not, for greater changes in contour, and for faster presentation rates. Melodies transformed by a reordering of component tones were no less discriminable than those transformed by the addition of novel frequencies.  相似文献   
290.
Studies that have addressed the possibility of hemispheric differences in semantic priming effects have yielded contradictory results. This paper reports the findings of two experiments intended to shed greater light on the issue of hemispheric differences in semantic priming. Experiment 1 used a hemiretinal paradigm and examined manual response latency and response accuracy to four types of word pairs; categorically related, syntactically related, unrelated, and pairs containing a nonword member. Experiment 2 examined the effects of unrecognized, disambiguating flank words on verbal responses to a centrally presented homograph. Experiment 1 yielded no significant visual field differences in magnitude of priming effects when response latency served as the dependent measure, although categorical relatedness facilitated response accuracy for left but not right visual field stimuli. In experiment 2, the disambiguating words had a significant effect on meaning interpretation of the homographs that was independent of visual field of presentation. Taken together, the results of these studies are interpreted as indicating that semantic aspects of linguistic input are automatically processed and can influence the content and latency of subsequent responses, whether presented to the left or right visual field.  相似文献   
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