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351.
352.
Kevin X. Cao Alice Booth Sebastien Ourselin Anna L. David Richard Ashcroft 《黑龙江环境通报》2018,38(7):475-481
The specialty of fetal surgery or fetal intervention is one of the most exciting emerging fields of modern medicine. It is made possible by decades of major developments in antenatal imaging, obstetric anaesthesia, fetal medicine, paediatric surgery, and of course by the bold and novel practitioners willing to take new steps to advance the field. Beginning in the 1970s, it has now reached a stage of maturity where there are several established in utero procedures and countless clinical trials and studies to develop more. But what is the legal situation that fetal surgeons find themselves in? What are the rights and legal protections for the fetus and the mother, both of which are arguably the patient? This article will address this question, discussing and summarising the current legal frameworks governing fetal surgery in the jurisdictions of the United Kingdom, European Court of Human Rights, and the United States of America as well as discuss what the future may hold and how researchers and physicians in the specialty can best navigate the legal environment. 相似文献
353.
The toxicity of aqueous solutions saturated with mixtures of hydrophobic organic liquids is contrasted to that of solutions prepared from solids. Data for a variety of mixtures are presented and are related to the solubilities of the components. It is shown that in the absence of biological interactive effects, the toxicity of a component in a saturated mixture of liquids will be equal to or less than that of a corresponding solution of its most toxic component. In contrast, for solutions derived from a mixture of solids, the toxicity will equal or exceed that of a corresponding saturated solution of its most toxic component, and will tend to increase with the complexity of the mixture. 相似文献
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Over the last 15 years, economists of Resources for the Future led by John Krutilla have been developing a new approach to wilderness preservation. This paper offers a concise exposition of their approach and adds a few steps. The basic ingredient of the new approach is a perception of declining net benefits of wilderness development and rising net benefits of wilderness preservation over time. These alter the entire shape of the benefit-cost analysis of potential development. The new steps involve reversibility, postponability, and recognition of multiple interest rates. 相似文献
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Richard Hogg 《Disasters》1980,4(3):299-310
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The possibility that suppressing the tobacco budworm, Heliothis virescens (F.), by means of genetic control will lead to short run crop yield sacrifices is examined. A simulation model of budworm/backcross population dynamics is used to investigate the effects of backcross releases which are too small or improperly timed. Apart from its potential for ultimate long-term suppression of the tobacco budworm, adverse short-term effects on crop yields are not likely to be a serious problem with a genetic control program. Furthermore, backcross release appears to have some potential as a substitute for chemical pesticides during the period prior to budworm elimination by genetic control. 相似文献
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Ranching the View: Subdivisions versus Agriculture 总被引:2,自引:0,他引:2