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121.
生殖系基因治疗的技术和伦理问题 总被引:3,自引:1,他引:2
生殖系基因治疗是通过对生殖系细胞的基因修饰,给该细胞发育而来的整个有机体及其后代带来永久性的遗传纠正。本文着重对生殖系治疗的现有技术条件,存在技术问题及各种观点作一归纳,主要试图反映生殖系基因治疗的科学背景及当代人的思考,希望有助于人们的思考。 相似文献
122.
Jackson F 《Science and engineering ethics》1998,4(2):155-170
The Human Genome Project (HGP) represents a massive merging of science and technology in the name of all humanity. While the
disease aspects of HGP-generated data have received the greatest publicity and are the strongest rationale for the project,
it should be remembered that the HGP has, as its goal the sequencing of all 100,000 human genes and the accurate depiction of the ancestral and functional relationships among these genes. The HGP will
thus be constructing the molecular taxonomic norm for humanity. Currently the HGP genomic baseline is almost exclusively skewed
toward North Atlantic European lineages through the extensive use of the Centre d’études du Polymorphisme Humaine (CEPH) data
set. More recently, the HGP has shifted to the use of volunteer donors since adequate informed consent had not been secured
from the CEPH families. No evidence exists that either the CEPH families or the current volunteers are the most appropriate
demographic or evolutionary lineages for the functional genomic studies that will guide production of new DNA based drugs,
targeted therapeutics and gene-based diagnostics. The lack of scientific representativeness of the HGP is a serious impediment
to its broad applicability. Yet this can be remedied, and five alternative sampling strategies are presented. In response
to the current exclusionary design of the HGP, there is noteworthy caution and skepticism in the African American community
concerning genetic studies. The Manifesto on Genomic Studies Among African Americans reflects both a desire to be systematically included in federally funded genomic studies and a desire to maintain some control
over the interpretation and application of research results. Representative sampling in the HGP is seen as an international
human rights issue with domestic ethical implications. 相似文献
123.
Libertarianism vs. Marxism: Reflections on G. A. Cohen‘s Self-Ownership, Freedom and Equality 总被引:1,自引:0,他引:1
Jan Narveson 《The Journal of Ethics》1998,2(1):1-26
Self-Ownership, Freedom and Equality is G.A. Cohens attempt to rescue something of the socialist outlook on society from the challenge of libertarianism, which Cohen identifies with the work of Robert Nozick in his famous book, Anarchy, State, and Utopia. Sympathizing with the leading idea that a person must belong to himself, and thus be unavailable for forced redistribution of his efforts, Cohen is at pains to reconcile the two. This cannot be done – they are flatly contrary. Moreover, equality is a nonsense principle, calling for such things as equal distribution of natural resources. But resources, as goods, are not natural: all require work to utilize. The only thing exchanged on markets is services, and estimates of value received are relevantly made only by those party to the exchanges in question. Imposition from above on voluntary exchange can only be socially counterproductive. 相似文献
124.
Will Kymlicka 《Ethical Theory and Moral Practice》1998,1(2):143-157
This paper is an introduction to a special issue on Nationalism, Multiculturalism and Liberal Democracy. It attempts to describe the state of the debate on issues of multiculturalism and nationalism within liberal-democratic theory. I suggest that there may be an emerging consensus on liberal culturalism – the view that certain group-specific rights or policies aimed at recognizing or accommodating ethnic and national groups are legitimate so long as they operate within certain constraints of liberal justice. I explore the possible reasons for this emerging consensus (including the lack of clear alternatives), and conclude with some suggestions about the likely avenues for future research in this area. 相似文献
125.
Since the observations of O. Pfungst the use of human-provided cues by animals has been well-known in the behavioural sciences
(“Clever Hans effect”). It has recently been shown that rhesus monkeys (Macaca mulatta) are unable to use the direction of gazing by the experimenter as a cue for finding food, although after some training they
learned to respond to pointing by hand. Direction of gaze is used by chimpanzees, however. Dogs (Canis familiaris) are believed to be sensitive to human gestural communication but their ability has never been formally tested. In three
experiments we examined whether dogs can respond to cues given by humans. We found that dogs are able to utilize pointing,
bowing, nodding, head-turning and glancing gestures of humans as cues for finding hidden food. Dogs were also able to generalize
from one person (owner) to another familiar person (experimenter) in using the same gestures as cues. Baseline trials were
run to test the possibility that odour cues alone could be responsible for the dogs’ performance. During training individual
performance showed limited variability, probably because some dogs already “knew” some of the cues from their earlier experiences
with humans. We suggest that the phenomenon of dogs responding to cues given by humans is better analysed as a case of interspecific
communication than in terms of discrimination learning.
Received: 30 May 1998 / Accepted after revision: 6 September 1998 相似文献
126.
Learning of fixed arbitrary sequences proceeds by idiosyncratic subsequencing and assembly of the resulting subsequences. An error item that just precedes a subjective subsequence is a closely constrained member of that subsequence. Identification and characterization of subjective subsequences were accomplished by analyses of forward serial learning, free recall, and backward serial learning. We conclude that ordinary serial learning cannot be represented by traditional continuous-process theories, but instead must be treated by an organizational model. 相似文献
127.
John Robert Anderson 《Cognitive psychology》1974,6(4):451-474
Three experiments are reported in which subjects learn propositions like A hippie is in the park. The experiments manipulate the number of such propositions involving a particular person (e.g., hippie) or a particular location (e.g., park). After learning the material, subjects are asked to judge whether particular probe propositions are from the study set. Times to make these judgments about probe propositions increase with the number of study propositions involving the person or location used in the probe proposition. A model is presented which assumes a subject simultaneously accesses memory from all concepts in a probe proposition and serially searches through all study propositions involving each concept. Search of memory terminates as soon as one search process from a concept finds the probe proposition or exhausts the study propositions attached to that concept. 相似文献
128.
Women in four high-status, male-dominated professions—architecture, law, medicine, and psychology—are described in terms of a variety of historical, social, and career variables. The women share common antecedents of their vocational choices and similar perceptions of their work, but the occupational groups are dissimilar on a number of dimensions. Psychologists stand in particular contrast to the other three groups of professionals, describing experiences and career patterns less in conflict with stereotypic female roles. These contrasts may reflect differences in the sex-typed characterizations of the professions even though all are male-dominated. 相似文献
129.
The combined and separate effects of parent-presented models and praise on specific vocalizations of three children (15, 17, and 20 months old) were investigated. The frequency of a specific vocalization was higher when parents modeled and praised it than when they did not. In addition, modeling and praise, when used in combination, had a greater effect on the frequency of specific vocalizations than when used separately. Three additional parents were asked to attempt, by any means they wished, to increase the frequency of a specific vocalization by their children. These parents used modeling almost, exclusively, and the children did not exhibit the specific vocalizations as frequently as did the children whose parents were instructed both to model and praise specific vocalizations. 相似文献
130.
The topic of transitions in automated driving is becoming important now that cars are automated to ever greater extents. This paper proposes a theoretical framework to support and align human factors research on transitions in automated driving. Driving states are defined based on the allocation of primary driving tasks (i.e., lateral control, longitudinal control, and monitoring) between the driver and the automation. A transition in automated driving is defined as the process during which the human-automation system changes from one driving state to another, with transitions of monitoring activity and transitions of control being among the possibilities. Based on ‘Is the transition required?’, ‘Who initiates the transition?’, and ‘Who is in control after the transition?’, we define six types of control transitions between the driver and automation: (1) Optional Driver-Initiated Driver-in-Control, (2) Mandatory Driver-Initiated Driver-in-Control, (3) Optional Driver-Initiated Automation-in-Control, (4) Mandatory Driver-Initiated Automation-in-Control, (5) Automation-Initiated Driver-in-Control, and (6) Automation-Initiated Automation-in-Control. Use cases per transition type are introduced. Finally, we interpret previous experimental studies on transitions using our framework and identify areas for future research. We conclude that our framework of driving states and transitions is an important complement to the levels of automation proposed by transportation agencies, because it describes what the driver and automation are doing, rather than should be doing, at a moment of time. 相似文献