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Fall und Kommentare
Gibt es eine Pflicht zum pr?natalen Nichtwissen? 相似文献Definition of the problem
This paper deals with the question whether the current German intellectual property right on pharmaceuticals is morally justifiable. To answer this question, I will map the relevant discourse and arrange the different positions with respect to their level of abstraction.Arguments
I underline that both deontological and consequentialist arguments point out the moral deficits within the system.Conclusion
The consequentialist position emphasizes the unsatisfying relationship between patented pharmaceutical costs and the number of innovations on the market. The deontological approach on the other hand highlights the dangers to citizens’ autonomy.Definition of the problem
Ruth Macklin’s influential essay “Dignity is a useless concept” has revitalized a broad debate on the question whether the concept of dignity is meaningful in medical ethics. In this paper, I would like to examine Macklin’s so-called redundancy claim: according to this claim, the concept of human dignity can be replaced by other concept(s)—the concept of autonomy most prominent among them. What is the meaning of this claim?Arguments
Starting from an analysis of Macklin’s arguments, I am going to show under which conditions a redundancy claim indeed leads to the eliminating consequences emphasized by its defenders—we should abandon the concept of dignity.Conclusion
I am going to identify the advantages of her position both in comparison with more radical eliminative standpoints as well as positions that regard it as valid, but unanalyzable. 相似文献In this perfusion magnetic resonance imaging study, the performances of different pseudo-continuous arterial spin labeling (PCASL) sequences were compared: two-dimensional (2D) single-shot readout with simultaneous multislice (SMS), 2D single-shot echo-planar imaging (EPI) and multishot three-dimensional (3D) gradient and spin echo (GRASE) sequences combined with a background-suppression (BS) module.
Materials and methodsWhole-brain PCASL images were acquired from seven healthy volunteers. The performance of each protocol was evaluated by extracting regional cerebral blood flow (rCBF) measures using an inline morphometric segmentation prototype. Image data postprocessing and subsequent statistical analyses enabled comparisons at the regional and sub-regional levels.
ResultsThe main findings were as follows: (i) Mean global CBF obtained across methods was were highly correlated, and these correlations were significantly higher among the same readout sequences. (ii) Temporal signal-to-noise ratio and gray-matter-to-white-matter CBF ratio were found to be equivalent for all 2D variants but lower than those of 3D-GRASE.
DiscussionOur study demonstrates that the accelerated SMS readout can provide increased acquisition efficiency and/or a higher temporal resolution than conventional 2D and 3D readout sequences. Among all of the methods, 3D-GRASE showed the lowest variability in CBF measurements and thus highest robustness against noise.
相似文献