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Sevoflurane concentrations in blood, brain, and lung were measured in an individual apparently dying from sevoflurane inhalation. Sevoflurane is a volatile nonflammable fluorinated methyl isopropyl ether inhaled anesthetic, chemically related to desflurane and isoflurane. The incidence of abuse of sevoflurane is lower than that of other drugs of abuse possibly due to its inaccessibility to the general public and less pleasurable and addicting effects. The dead subject was an anesthetist found prone in bed holding an empty bottle of sevoflurane (Ultane). Serum, urine, and liver were screened for numerous drugs and metabolites using enzyme immunoassays and gas chromatography-mass spectrometry. Analysis did not reveal presence of any drug, including ethanol, other than sevoflurane. Sevoflurane was determined by headspace gas chromatography and revealed concentrations of 15 microg/mL in blood and 130 mg/kg in brain and lung. Autopsy revealed pulmonary edema and frothing in the lung, pathological findings associated with death by sevoflurane or hypoxia. The cause of death was ruled as sevoflurane toxicity and the manner of death as accident.  相似文献   
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This article demonstrates that in recent years, patent settlements between branded and generic manufacturers involving "reverse payments" from branded manufacturers to generic manufacturers have received close antitrust scrutiny, driven by concerns that such settlements harm consumers by delaying the entry of lower-priced generic drugs. The authors note that such settlements will be a focus of the Obama Administration's antitrust enforcement policy, yet there is a growing consensus among the courts that such settlements are anticompetitive only under narrow sets of circumstances. In this article, the authors present an analytical framework for evaluating the competitive effects of patent settlements, including those involving reverse payments, and demonstrate that these settlements can benefit consumers. Thus, the authors conclude that while continued scrutiny of such settlements is important, broad brush treatments are inappropriate and only a more individualized evaluation can correctly determine the competitive effects of a particular settlement agreement.  相似文献   
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The ability to determine the age of fingerprints would be immeasurably beneficial in criminal investigations. We explore the possibility of determining the age of fingerprints by analyzing various compounds as they diffuse from the ridges to the valleys of fingerprints using matrix‐assisted laser desorption/ionization mass spectrometry imaging. The diffusion of two classes of endogenous fingerprint compounds, fatty acids and triacylglycerols (TGs), was studied in fresh and aged fingerprints on four surfaces. We expected higher molecular weight TGs would diffuse slower than fatty acids and allow us to determine the age of older fingerprints. However, we found interactions between endogenous compounds and the surface have a much stronger impact on diffusion than molecular weight. For example, diffusion of TGs is faster on hydrophilic plain glass or partially hydrophilic stainless steel surfaces, than on a hydrophobic Rain‐x treated surface. This result further complicates utilizing a diffusion model to age fingerprints.  相似文献   
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Abstract

Some of the poorest peasant households in one of China's inland provinces are being hurt by current government policies toward agriculture. This is the distinct impression obtained during two months of travel and research in Yunnan Province during mid-1988. As consultants to an international development project, we had an opportunity to explore the hill districts of northern Yunnan in a four-wheel drive, free to conduct interviews with grass-roots officials and peasant families. A total of thirteen villages were investigated, selected largely by ourselves.  相似文献   
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