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31.
An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm3, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H+], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d3-THC + H+]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r2 = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette® collection, 26 of the 40 cases had an undetectable THC.  相似文献   
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In April 1986, one-month-old Lance Tyler Steinhaus sustained serious injuries, attributed to abuse by his father, that left him comatose. His mother and his physicians agreed that he should not be treated aggressively. The Redwood County (Minnesota) Welfare Department obtained a temporary order restraining withdrawal of Lance's antibiotic therapy. Lance's mother and Dr. David Steinhorn, a pediatrician, appealed to the County Court to dissolve the temporary injunction. Judge George I. Harrelson in this decision denied their request on the grounds that both state and federal law establish that infants with life-threatening conditions have a right to medically-indicated treatment and that Lance Steinhaus had such a right because he was in a "vegetative state" rather than technically "comatose." [Editor's note: After conducting another hearing on Lance's neurological status, the court ruled on 18 October that Lance was irreversibly comatose and ordered only "comfort care."]  相似文献   
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International Journal of Politics, Culture, and Society - On the basis of empirical material from a city bordering Syria and Turkey, this article aims to situate the city’s emerging landscape...  相似文献   
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