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961.
Gerrand N 《Journal of applied philosophy》1993,10(2):175-187
ABSTRACT The 1987 Amendment to the Infertility (Medical Procedures) Act (Vic) allows the creation of embryos specifically for research purposes, as long as the proposed experiment takes place within 24 hours. The purpose of this paper is to determine whether there is aany significant ethical difference between creating embryos specifically for research and using those that are surplus from the new reproductive technologies. The relevant arguments in this debate can be grouped under three heads: those focussing on the embryo; those focussing on the possible consequences of these practices and those focussing on the women who donate the eggs. 相似文献
962.
Signaling Mechanisms Mediating BDNF Modulation of Synaptic Plasticity in the Hippocampus 总被引:8,自引:0,他引:8 下载免费PDF全文
Wolfram A. Gottschalk Hao Jiang Nicole Tartaglia Linyin Feng Alexander Figurov Bai Lu 《Learning & memory (Cold Spring Harbor, N.Y.)》1999,6(3):243-256
Although recent studies indicate that brain-derived neurotrophic factor (BDNF) plays an important role in hippocampal synaptic plasticity, the underlying signaling mechanisms remain largely unknown. Here, we have characterized the signaling events that mediate the BDNF modulation of high-frequency synaptic transmission. Mitogen-associated protein kinase (MAPK), phosphotidylinositol-3 kinase (PI3K), and phospholipase C-γ (PLC-γ) are the three signaling pathways known to mediate neurotrophin signaling in other systems. In neonatal hippocampal slices, application of BDNF rapidly activated MAPK and PI3K but not PLC-γ. BDNF greatly attenuated synaptic fatigue at CA1 synapses induced by a train of high-frequency, tetanic stimulation (HFS). Inhibition of the MAPK and PI3K, but not PLC-γ, prevented the BDNF modulation of high-frequency synaptic transmission. Neurotrophin-3 (NT-3), a close relative of BDNF, did not activate MAPK or PI3K and had no effect on synaptic fatigue in the neonatal hippocampus. Neither forskolin, which activated MAPK but not PI3 kinase, nor ciliary neurotrophic factor (CNTF), which activated PI3K but not MAPK, affected HFS-induced synaptic fatigue. Treatment of the slices with forskolin together with CNTF still had no effect on synaptic fatigue. Thus, although the activation of MAPK and PI3K is required, the two together are not sufficient to mediate the BDNF effect. Inhibition of new protein synthesis by anisomycin or cycloheximide did not prevent the BDNF effect. These data suggest that BDNF modulation of high-frequency transmission is independent of protein synthesis but requires MAPK and PI3K and yet another signaling pathway to act together in the hippocampus. 相似文献
963.
Roger C. Katz Nicole Zenger 《Journal of psychopathology and behavioral assessment》1999,21(3):183-189
We describe a brief self-report measure for assessing hypochondriacal fears in adults. Called the Survey of Health Concerns (SHC), the measure was developed using DSM IV criteria for diagnosing hypochondriacal disorder as a guide. The measure was standardized on a sample of 188 college students. It was shown to have good internal and temporal reliability over a 2-week period. Moreover, scores on the SHC correlated significantly with worry proneness as measured by the Penn State Worry Questionnaire, and with the Hs scale of the MMPI-2, which together support the convergent validity of the measure. While men and women scored the same, participants who were being treated for a medical condition scored higher than those who were not being treated. Men who were under a doctor's care scored especially high, although this was based on a small sample of men and the effect could be spurious. A principal component factor analysis revealed two primary factors: one that described participants who felt poorly, made frequent trips to the doctor, and were fearful of illness and dying, and another that described participants who were particularly fearful of infectious diseases and took active steps to avoid becoming sick. Relatively little is known about hypochondriacal disorder. One reason for the dearth of knowledge in this area is that there has been no practical and reliable way to assess hypochondriacal fears, or more generally speaking, people's tendency to worry about their health. The SHC may help to fill this void. Results are admittedly preliminary and further study in medical settings is needed. 相似文献
964.
This study explores the development of strategic behaviour related to kindness and intelligence dimensions in 3‐ to 8‐year‐old children. Previous research systematically highlighted the affective bias that limited young children's thinking and behaving in strategic terms. We argue that young children are able to grasp specific dimensions of social affordances from personality traits and behaviour exemplifying these traits. The results obtained in the partner choice paradigm revealed a developmental increase in social utility understanding. This supports our hypothesis of early social affordances understanding and provides empirical evidence that affective bias did not drastically influence strategic partner choice in 4‐ to 8‐year‐old children. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
965.
A sample of 96 trolley car drivers was used to investigate the relationship between aggressive behavior of passengers and burnout, the moderating effect of conflict management behavior of the drivers on this relationship; and the influence of burnout on customer-friendliness, passenger complaints, and absenteeism. The results show that aggressive behavior of passengers was related to all 3 burnout dimensions. The relationship of aggressive behavior of customers and professional efficacy was qualified by 2 significant interactions with 2 conflict management behavior styles: forcing and avoiding. The interactions showed that too much forcing as well as too much avoiding are related to less professional efficacy for drivers confronted with aggressive behavior. Passenger complaints were only related to less professional efficacy. The customer-friendliness of the drivers was related to less cynicism and more professional efficacy. Absenteeism was only related to exhaustion. 相似文献
966.
Abstract. Resolution of the entropy‐evolution problem was a significant issue for Pierre Teilhard de Chardin throughout his scientific career. Although never truly satisfied with his solution, he proposed that all energy must be psychic and contain two components. Tangential energy is related to physical energy. Radial energy in some way accounts for increasing complexity and consciousness in evolution. Analysis of developments in thermodynamics, statistical mechanics, and information theory show that Gibbs free energy contains both calorimetric and noetic components, thus validating Teilhard's intuition. 相似文献
967.
This article presents statistical data depicting the employment of persons with disabilities at a federal installation using a recruitment intervention designed to increase the presence of persons with disabilities. The data were obtained by reviewing archival recruitment accessions that span 5 years (1999–2003). The organization under study is a highly technical Department of Defense organization constituted primarily of engineers and scientists and has been in existence and a major contributor in national defense for many years. Earlier recruitment data are not available. 相似文献
968.
In 1917 Pierre Teilhard de Chardin wrote an essay that proposes union as a way to observe how the process of evolution takes place. He spent the remainder of his life broadening and sharpening the vision, which was based on union in nature. We propose that this vision and the historical development of thermodynamics and classical statistical mechanics offer insight into union and even into the divine life that many Christians believe to be triadic. We briefly situate union in the triune divine life in early Christian tradition as it was believed and practiced. We then interpret three stages of development in the sciences of thermodynamics and statistical mechanics that support the theme of union in nature. Next we describe the development of Teilhard's thought during his scientific career and his tests of the theme of union, principally in his private journals, now being edited. We offer examples of Teilhard's application of union to his own spiritual life and compare his understanding of union with those of Paul the Apostle and John of the Cross. Finally, although the Christian God's triadic life was not a particular concern of Teilhard, we propose union in nature as a vestige of the divine life. 相似文献
969.
Forty-three women who had worked outside of the home prior to becoming pregnant and had returned to the same place of employment after the birth of their children participated in the study. To do so, they responded to a two-part questionnaire asking about their work lives (e.g., level of job satisfaction before, during, and after their pregnancies) and demographic characteristics (e.g., occupation). The results indicated that their job satisfaction was significantly greater before their pregnancies than either during or after their pregnancies. Job satisfaction during pregnancy had a significant, positive correlation with satisfaction with organizational maternity leave policies. Perceived reactions from women's coworkers and supervisors were also examined. Implications for these findings for organizations are discussed. Limitations of the study, and how they might be rectified in future research, are also addressed. 相似文献
970.
Although research has demonstrated that marriage education has positive effects on relationship quality, little is known about how such services impact relationships where one partner is incarcerated. The current study implemented an adapted version of the Prevention and Relationship Enhancement Program (PREP Inside and Out) for inmates in Oklahoma correctional facilities. Inmates, with or without their partners, participated in the 12-hour program. The impact of the program was investigated on a range of relationship variables including satisfaction with relationship, dedication, confidence, communication skills, friendship, and negative interactions as reported by the inmate partner. Participants reported substantial gains in all variables and in overall satisfaction with their relationship after completing the program, regardless of their gender and racial/ethnic background. Implications for future marriage education programs and research in prisons are discussed. 相似文献