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411.
The ethics of managing obstetric patients in medical disasters poses ethical challenges that are unique in comparison to other disaster patients, because the medical needs of two patients--the pregnant patient and the fetal patient--must be considered. We provide an ethical framework for doing so. We base the framework on the justice-based prevention of exploitation of populations of patients, both obstetric and non-obstetric, in medical disasters. We use the concept of exploitation to identify a spectrum from ethically acceptable, to ethically challenging, to ethically unacceptable, management of obstetric patients in medical disasters. We also address the ethics of the care of obstetric and neonatal patients when the resources of a hospital are completely overwhelmed in a large-scale medical disaster.  相似文献   
412.
In white matter disorders such as leukodystrophies (LD), periventricular leucomalacia (PVL), or multiple sclerosis (MS), the hypomyelination or the remyelination failure by oligodendrocyte progenitor cells involves errors in the sequence of events that normally occur during development when progenitors proliferate, migrate through the white matter, contact the axon, and differentiate into myelin-forming oligodendrocytes. Multiple mechanisms underlie the eventual progressive deterioration that typifies the natural history of developmental demyelination in LD and PVL and of adult-onset demyelination in MS. Over the past few years, pathophysiological studies have mostly focused on seeking abnormalities that impede oligodendroglial maturation at the level of migration, myelination, and survival. In contrast, there has been a strikingly lower interest for early proliferative and differentiation events that are likely to be equally critical for white matter development and myelin repair. This review highlights the Yin and Yang principles of interactions between intrinsic factors that coordinately regulate progenitor cell division and the onset of differentiation, i.e. the initial steps of oligodendrocyte lineage progression that are obviously crucial in health and diseases.  相似文献   
413.
Medical ethics often is treated as applied ethics, that is, the application of moral philosophy to ethical issues in medicine. In an earlier paper, we examined instances of moral philosophy's influence on medical ethics. We found the applied ethics model inadequate and sketched an alternative model. On this model, practitioners seeking to change morality "appropriate" concepts and theory fragments from moral philosophy to valorize and justify their innovations. Goldilocks-like, five commentators tasted our offerings. Some found them too cold, since they had already abandoned applied ethics; others too hot, since they still find the applied ethics model to their taste. We reply that the appropriation model offers an empirically testable account of the historical relationship between moral philosophy and medical ethics that explains why practitioners appropriate concepts and fragments from moral philosophy. In contrast, the now fashionable common morality theory neither explains moral change nor why practitioners turn to moral philosophy.  相似文献   
414.
This study was designed to investigate the effects of aging on consciousness in recognition memory, using the Remember/Know/Guess procedure (Gardiner, J. M., & Richarson-Klavehn, A. (2000). Remembering and Knowing. In E. Tulving & F. I. M. Craik (Eds.), The Oxford Handbook of Memory. Oxford University Press.). In recognition memory, older participants report fewer occasions on which recognition is accompanied by recollection of the original encoding context. Two main hypotheses were tested: the speed mediation hypothesis (Salthouse, T. A. (1996). The processing-speed theory of adult age differences in cognition. Psychological Review, 3, 403–428) and the executive-aging hypothesis (West, R. L. (1996). An application of prefrontal cortex function theory to cognitive aging. Psychological Bulletin, 120, 272–292). A group of young and a group of older adults took a recognition test in which they classified their responses according to Gardiner, J. M., & Richarson-Klavehn, A. (2000). Remembering and Knowing. In E. Tulving & F. I. M. Craik (Eds.), The Oxford Handbook of Memory. Oxford University Press. remember-know-guess paradigm. Subsequently, participants completed processing speed and executive function tests. The results showed that among the older participants, R responses decreased, but K responses did not. Moreover, a hierarchical regression analysis supported the view that the effect of age in recollection experience is determined by frontal lobe integrity and not by diminution of processing speed.  相似文献   
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