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131.
132.
Assessment of risk is one of the key issues in the field of responsible conduct of research which covers discourses of research ethics and research integrity. The principle of minimizing risks and balancing of risks and benefits is one of the main requirements of research ethics. In addition, the content of informed consent that is another fundamental principle of research ethics derives from the assessment of risks and benefits related to a particular research project. Risk assessment also plays a crucial role in methodological design of the research project. This is an important point where research ethics and research integrity discourses overlap. Firstly, because the choice of a control group (e.g., placebo control) is a key ethical issue related to the protection of the research subjects' interests. Secondly, because the quality of the research data, that is one of the key elements of research integrity, is closely connected to the choice of research methodology as well. The problem of biased interpretation or manipulation of risk related features of biomedical research should also be taken into account. Despite the importance of the concept of risk to the field of biomedical research, its relevance has not yet attracted a sufficient attention in the responsible conduct of research debate.  相似文献   
133.
The Helsinki Declaration is a very important document regarding the protection of patients’ rights in clinical trials and one of the fundamental sources of operational principles for every ethics committee. Although they have been updated, the international guidelines for ethics committees continually fail to address certain issues pertaining to the protection of patients’ rights in clinical trials. These issues include, most significantly, the method of electing ethics committees (a free, secret ballot should be preferred to direct appointment), the avoidance of conflict of interest during the election of ethics committee members, and the necessary insurance coverage for the participants of clinical trials. Polish law should, on the other hand, be developed in such way as to not limit the effectiveness of ethics committees in protecting patients’ rights in clinical trials. The ideal solution would be to draft a uniform law concerning not only clinical trials, but all medical experiments. The opinions of experts who have been reviewing medical research projects for several years may prove to be especially valuable in this setting. This paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005. The author is Chairman, Bioethics Committee of the Warsaw Regional Chamber of Physicians and Dentists.  相似文献   
134.
Medicine is a scientific discipline, but it is sometimes difficult to separate what is scientific and what is a clinical, practical activity. Man is the object, but he is always the subject of medical research and therefore these two elements become closely bound together by a thread of moral interdependencies. Every mentor of a young academic and all institutions dealing with the teaching of and research into medicine must understand multidimensional, multifaceted, and multilevel aspects of their activity and give them due regard in the educational process. The educational mission of an academic institution and of the teacher working there may be summed up in one phrase: Teach thinking! At the same time, the task of a school and the individual mentor is to teach the student to distinguish personal freedom from a lack of the feeling of responsibility. The medieval principle “Universitas magistrorum et scholarium”, and thus the corporation, the community of teachers and students, has not lost any of its relevance and value today. The situation is, in its far-reaching consequences, tragic in which the “insufficiently tutored teach”. Both physician and teacher, and especially physician-teacher, are not only professions, but also callings. This paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005.  相似文献   
135.
In everyday life, the optic flow associated with the performance of complex actions, like walking through a field of obstacles and catching a ball, entails retinal flow with motion energy (first-order motion). We report the results of four complex action tasks performed in virtual environments without any retinal motion energy. Specifically, we used dynamic random-dot stereograms with single-frame lifetimes (cyclopean stimuli) such that in neither eye was there retinal motion energy or other monocular information about the actions being performed. Performance on the four tasks with the cyclopean stimuli was comparable to performance with luminance stimuli, which do provide retinal optic flow. The near equivalence of the two types of stimuli indicates that if optic flow is involved in the control of action, it is not tied to first-order retinal motion.  相似文献   
136.
How do we determine where we are heading during visually controlled locomotion? Psychophysical research has shown that humans are quite good at judging their travel direction, or heading, from retinal optic flow. Here we show that retinal optic flow is sufficient, but not necessary, for determining heading. By using a purely cyclopean stimulus (random dot cinematogram), we demonstrate heading perception without retinal optic flow. We also show that heading judgments are equally accurate for the cyclopean stimulus and a conventional optic flow stimulus, when the two are matched for motion visibility. The human visual system thus demonstrates flexible, robust use of available visual cues for perceiving heading direction.  相似文献   
137.
Sources of variability in children’s language growth   总被引:1,自引:0,他引:1  
The present longitudinal study examines the role of caregiver speech in language development, especially syntactic development, using 47 parent–child pairs of diverse SES background from 14 to 46 months. We assess the diversity (variety) of words and syntactic structures produced by caregivers and children. We use lagged correlations to examine language growth and its relation to caregiver speech. Results show substantial individual differences among children, and indicate that diversity of earlier caregiver speech significantly predicts corresponding diversity in later child speech. For vocabulary, earlier child speech also predicts later caregiver speech, suggesting mutual influence. However, for syntax, earlier child speech does not significantly predict later caregiver speech, suggesting a causal flow from caregiver to child. Finally, demographic factors, notably SES, are related to language growth, and are, at least partially, mediated by differences in caregiver speech, showing the pervasive influence of caregiver speech on language growth.  相似文献   
138.
We examined associations between children’s peer relationships and (a) their parents’ social competence as well as (b) their parents’ behaviors during the children’s peer interactions. Participants were families of 124 children ages 6–10 (68% male), 62 with ADHD and 62 age- and sex-matched comparison youth. Children’s peer relationships were assessed via parent and teacher report, and sociometric nominations in a lab-based playgroup. Parental characteristics were assessed via parent self-report and observations of behavior during their child’s playgroup. After statistical control of relevant covariates, parents of children with ADHD reported poorer social skills of their own, arranged fewer playdates for their children, and displayed more criticism during their child’s peer interaction than did parents of comparison youth. Parents’ socialization with other parents and facilitation of the child’s peer interactions predicted their children having good peer relationships as reported by teachers and peers, whereas parental corrective feedback to the child and praise predicted poor peer relationships. Parents’ ratings of their child’s social skills were positively associated with ratings of their own social skills, but negatively associated with criticism and facilitation of the child’s peer interactions. Relationships between parental behaviors and peer relationships were stronger for youth with ADHD than for comparison youth. The relevance of findings to interventions is discussed.  相似文献   
139.
140.
The term childhood amnesia refers to the inability of adults to remember events from their infancy and early childhood. If we plot the number of memories that adults can recall as a function of age during childhood, the number of memories reported increases gradually as a function of age. Typically, this finding has been used to argue that gradual changes in memory development contribute to a gradual decline in childhood amnesia during the preschool period. Alternatively, it is possible that pooling data across participants has obscured more abrupt, stage-like changes in the remission of childhood amnesia. In the present study we examined the number and distribution of childhood memories for individual participants. Six adults were repeatedly interviewed about their childhood memories. We found that the distribution of adults' early childhood memories may be less continuous than pooled data suggest. This finding has important implications for current explanations of childhood amnesia.  相似文献   
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