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131.
This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds.  相似文献   
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This report assesses the effects on peripheral oxygen saturation and heart rate that positional restraint induces when a person is prone, handcuffed, and "hog-tied." Peripheral oxygen saturation and heart rate were monitored at rest, during exercise, and during recovery from exercise for 10 adult subjects. The effects of positional restraint produced a mean recovery time that was significantly prolonged. Consequently, the physiological effects produced by positional restraint should be recognized in deaths where such measures are used.  相似文献   
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Pittenger  John C. 《Publius》1992,22(1):1-19
In Garcia v. San Antonio Metropolitan Transit Authority (1985),Justice Harry Blackmun held that the Tenth Amendment does notprevent the Congress from subjecting state and local governmentsto the provisions of the Fair Labor Standards Act, concludingthat the "political safeguards offederalism" are generally adequateto protect state interests on the national scene. This articleexamines the intellectual foundations of the "political safeguardsof federalism" and finds them inadequate. It then surveys thepost-Garcia scholarship to ascertain whether an alternativetheory of the Tenth Amendment has emerged. Concluding that ithas not, the author suggests the need for afresh approach inview of the hints contained in Justice Sandra Day O'Connor'sopinion in Gregory v. Ashcroft (1991) that five justices maybe ready to reexamine the central thesis of Garcia.  相似文献   
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Many phenomena of interest to political scientists involve what may be termed impersonal influence; that is, influence that derives from individuals' perceptions of others' attitudes, beliefs, or experiences. Others in this case refers not to the close friends and acquaintances that concerned the authors of classics such asThe People's Choice andPersonal Influence, but rather to the anonymous others outside an individual's realm of personal contacts. Modern mass media facilitate the influence of anonymous others by devoting considerable time and attention to portraying trends in mass opinion. This study explores the rationale for theories of impersonal influence, synthesizing existing research findings falling under this general theoretical framework, and investigating its psychological underpinnings using experiments embedded in representative surveys.  相似文献   
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