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111.
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
115.
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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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
119.
Gilchrist E Jongekrijg F Harvey L Smith N Barron L 《Forensic science international》2012,219(1-3):50-56
Gunshot residue (GSR) is commonly analysed in forensic casework using either scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) or gas chromatography-mass spectrometry (GC-MS). Relatively little work has been reported on the post-discharge GSR content of non-metallic inorganic or low molecular weight organic anions to distinguish between different ammunition types. The development of an analytical method using suppressed micro-bore anion exchange chromatography (IC) is presented for the analysis of GSR. A hydroxide gradient was optimised for the separation of 19 forensically relevant organic and inorganic anions in <23min and sensitivities of the order of 0.12-3.52ng of anion detected for all species were achieved. Along with an optimised extraction procedure, this method was applied to the analysis of post-ignition residues from three selected ammunition types. By profiling and comparing the anionic content in each ammunition residue, the possibility to distinguish between each type using their anionic profiles and absolute weight is presented. The potential for interference is also discussed with respect to sample types which are typically problematic in the analysis of GSR using SEM-EDX and GC-MS. To the best of our knowledge this represents the first study on the analysis of inorganic anions in GSR using suppressed ion chromatography. 相似文献
120.
Based on ethnographic data, this essay analyzes the social order properties of a poor urban street, in a small city in the
northeast United States, on which drug dealing is the principle occupation. Rather than treating drug dealing as an agent
of disorder, we focus on the order properties of drug dealing and the ordered character of the local code of conduct that
develops around it. Like Sudhir Venkatesh (American Journal of Sociology 103:82–111, 1997) we examine the interface between drug dealing and the neighborhood. However, in this small urban space the drug dealers
are not outsiders, rather, they are long term residents: established insiders who are well integrated into community life.
As such their work practices and the requirements they place on behavior in public spaces impact the neighborhood in comprehensive
ways. We detail the phenomenon Elijah Anderson called the “code of the street” (Anderson 1999) as a set of practices and social markers, a local Interaction Order (Goffman, American Sociological Review 48:1–17, 1983; Rawls, Sociological Theory 2:136–149, 1987), that furnishes basic day to day sensemaking tools for residents (Rawls 2009). We propose that this order has a constitutive character that furnishes stable expectations (Garfinkel 1963, 1967) for meaningful social action and identity in the neighborhood. In a context of industrial decline and urban poverty, drug
dealing careers constitute a major socialization factor, that touches everyone here—especially children. 相似文献