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111.
Underwood A 《Newsweek》2006,148(17):65
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Our headspace gas chromatographic flame ionization detection (HS-GC-FID) method for ethanol determination showed slightly, but consistently, low ethanol concentrations in whole blood (blood) in proficiency testing programs (QC-samples). Ethanol and acetaldehyde were determined using HS-GC-FID with capillary columns, headspace equilibration temperature (HS-T degrees ) of 70 degrees C and 20 min equilibration time (HS-EqT). Full factorial designs were used to study the variables HS-T degrees (50 degrees -70 degrees C), HS-EqT (15-25 min), ethanol concentration (0.20-1.20 g/kg) and storage at room temperature (0-6 days) with three sample-sets; plasma, hemolyzed blood and non-hemolyzed blood. A decrease in the ethanol concentration in blood was seen as a nearly equivalent increase in the acetaldehyde concentration. This effect was not observed in plasma, indicating chemical oxidation of ethanol to acetaldehyde in the presence of red blood cells. The variables showed different magnitude of effects in hemolyzed and non-hemolyzed blood. A decrease in ethanol concentration was seen even after a few days of storage and also when changing the HS-T degrees from 50 to 70 degrees C. The formation of acetaldehyde was dependent on all the variables and combinations of these (interactions) and HS-T degrees was involved in all the significant interaction effects. Favorable instrumental conditions were found to be HS-T degrees of 50 degrees C and HS-EqT of 15-25 min. The ethanol concentrations obtained for the range 0.04-2.5 g/kg after analyzing authentic forensic blood samples with a HS-T degrees of 50 degrees C were statistically significantly higher than at 70 degrees C (+0.0154 g/kg, p < 0.0001, n = 180). In conclusion, chemical oxidation of ethanol to acetaldehyde in the presence of red blood cells has been shown to contribute to lowered ethanol concentrations in blood samples. Storage conditions before analysis and the headspace equilibration temperature during analysis were important for the determination of blood ethanol concentrations.  相似文献   
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Patrick Vaughan is Reader in health care epidemiology, Gill Walt is Lecturer in health policy and Anne Mills is Lecturer in health economics, at the Evaluation and Planning Centre for Health Care, London School of Hygiene and Tropical Medicine, Gower Street, London WC1, United Kingdom. A previous version of this paper was prepared for the Commonwealth Secretariat, London, for the Conference of Commonwealth Health Ministers held in Ottawa, Canada, in October 1983.  相似文献   
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Within the last 20 years, the fragile symbiotic relationship between physicians and hospitals has become increasingly strained. Physicians have created new healthcare delivery systems, including a host of for-profit, physician-owned specialty hospitals. Proponents of specialty hospitals argue that they provide high quality facilities and allow for innovative treatments. Opponents, however, contend that such hospitals "cherry pick" patients who otherwise would help to subsidize general hospitals, and point to the various fraud and abuse issues raised by physician-owned specialty hospitals. This Article examines the specialty hospital phenomenon and the arguments for and against such entities. It also analyzes whether an extension of the present federal moratorium on the construction of new physician-owned specialty hospitals is in the best interests of the country's healthcare system. The author concludes that the data are unclear as the overall impact of such hospitals and that they should not be further constrained until when and if the facts are clear.  相似文献   
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The good heart     
Underwood A 《Newsweek》2005,146(14):48-52, 54-5
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Biobanks are increasingly seen as new tools for medical research. Their main purpose is to collect, store, and distribute human body materials. These activities are regulated by legal instruments which are heterogeneous in source (national and international), and in form (binding and non-binding). We analyse these to underline the need for a new model of governance for modern biobanks. The protection initially ensured by respect for fundamental rights will need to focus on more interactions with society in order to ensure biobanks' sustainability. International regulation is more oriented on ethical principles and traces the limits of the uses of genetics, while European regulation is more concerned with the protection of fundamental rights and the elaboration of standards for biobanks' quality assurance. But is this protection adequate and sufficient? Do we need to move from the biomedical research analogy to new forms of legal protection, and governance systems which involve citizens?  相似文献   
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