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A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.  相似文献   
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Allele frequencies for the 15 autosomic STR loci included in the PowerPlex 16 System kit (Promega Corp.) were estimated from a sample of 143 unrelated individuals living in Capital Federal and in Buenos Aires Metropolitan Area, Argentina. Population showed to be in HWE.  相似文献   
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This paper examines the procedural culture that shaped ethnic and national identities in late nineteenth‐century western Guatemala. Rooted in face‐to‐face encounters between departmental jefes políticos (departmental governors) and local Maya communities, this procedural culture emerged from routines of governance such as annual municipal inspections, ethnic struggles for municipal control, and local efforts to title community lands that led Maya and state officials to develop contrasting understandings of each other and their relations. Far from precipitating a national identity of mutual belonging, state formation here intensified the racism and political violence that would rend Guatemala during the century to come.  相似文献   
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Economic Change and Restructuring - Corruption is often a source of contentious debate, covering different areas of knowledge, such as philosophy and sociology. In this paper we assess the effects...  相似文献   
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A 35-year-old multipara died suddenly of a pulmonary embolism about 12 h after delivery. The morphological features and the entry site of the emboli into the circulation suggested that they were decidual cells. Intact decidual cells accounted for only a minority of the emboli: the great majority were cells that had lost their nuclei and/or had been fragmented. The presence of embolized areas, accompanied by fibroblasts and newly formed capillaries, suggested that the embolization process had started before the beginning of labor. However, no symptoms suggesting embolism had been recorded on the clinical chart.  相似文献   
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Free‐market reforms in the last quarter of the twentieth century weakened the point of production—labor unions—as the source of effective nonparty political countermovement to liberal capitalism. Has another significant source of societal resistance arisen in association with the resurgence of market economics? Building on the work of Karl Polanyi, this article argues that circuits of exchange—the commodification of labor, land, and money—can be powerful sources of movement against contemporary forms of free‐market capitalism. It draws on the cases of Argentina, Bolivia, and Ecuador to explore how Polanyi's exchange‐based approach helps to elucidate three phenomena: the great variety of identities behind the myriad movements against free‐market capitalism, the emergence of community as a powerful locus for organizing, and the proliferation of new forms of transgressive and highly disruptive direct action to reinforce the debilitated effectiveness of the strike.  相似文献   
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Given the general expectation that forest loss can alter biodiversity patterns, we hypothesize that blow fly species abundances differ in a gradient of native vegetation cover. This study was conducted in 17 fragments across different landscapes in central Brazil. Different land cover type proportions were used to represent landscape structure. In total, 2334 specimens of nine species of Calliphoridae were collected. We used principal component analysis (PCA) to reduce dimensionality and multicollinearity of the landscape data. The first component explained 70%, and it represented a gradient of forest‐pasture land uses. Alien species showed a wide distribution in different fragments with no clear relationship between the abundance values and the scores of PCA axes, whereas native species occurred only in areas with a predominance of forest cover. Our study revealed that certain native species may be sensitive to forest loss at the landscape scale, and they represent a bioindicator in forensic entomology.  相似文献   
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