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141.
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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Kimbol AS 《Journal of health law》2005,38(4):633-672
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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Laurence?D.?MeeEmail author 《International Environmental Agreements: Politics, Law and Economics》2005,5(3):227-263
This study examines the role of the UN’s programmes for environment and development (UNEP and UNDP) in the genesis and implementation
of multilateral environmental agreements (MEAs). This is set in the wider context of the changing dominant focus of the international
agenda, from ‘environment’ at the Stockholm Conference in 1972, to ‘environment and development’ at Rio in 1992, and ‚sustainable
development’ in Johannesburg in 2002. UNDP is a development organisation strongly rooted in its country office network. Its
role is becoming increasingly normative however, particularly since 2002 when UNDP opted to root most of its activities on
the Millennium Development Goals. UNEP, as an environmental organisation has been successful at catalysing MEAs at the global
and regional level; but without a significant increase in its budget over 30 years, its capacity has been spread very thinly.
Many of the institutional arrangements for MEAs have effectively become independent of UNEP resulting in a very loosely and
sometimes poorly coordinated network. Two case studies are used to illustrate the current institutional arrangements: UNEP’s
Regional Seas Conventions and Protocols, and the Convention for Biological Diversity. These illustrate the fragmentation of
current institutions, the need for strengthened technical and scientific support, the importance of addressing problems at
their root causes and the need to increase the devolution of global governance to the regional level. Satisfying the identified
needs requires actions within the remit of both UNEP and UNDP. It is argued that current institutional arrangements have not
kept pace with the requirements of evolving policy. As part of a reform process, one option may be to merge the two programmes
into a single structure that conserves and strengthens vital technical functions but enables a balanced and integrated approach
to sustainable development. 相似文献
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