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Hypertension is a growing medical concern in the United States. With the number of Americans suffering from hypertension increasing, the use of antihypertensives such as beta-blockers is increasing as well. In fact, three beta-blockers - atenolol, metoprolol and propranolol - were among the 200 most prescribed medications in the United States in 2003. Pilots that successfully manage their hypertension can remain certified to fly. The Federal Aviation Administration currently designates approximately 8% of active pilots as "hypertensive with medication". The Civil Aerospace Medical Institute (CAMI) performs toxicological evaluation on victims of fatal aviation accidents. At CAMI beta-blockers are analyzed using gas chromatography with mass spectrometric detection. We have, however, recently developed a liquid chromatography with mass spectrometric detection (LC/MS) method for the simultaneous quantitation of three commonly prescribed beta-blockers, atenolol, metoprolol and propranolol. One advantage of our LC/MS method is the specificity provided by an ion trap MS. Utilizing an ion trap MS, we were able to conduct MS/MS and MS/MS/MS on each analyte. This method also eliminates the time-consuming and costly derivitization step necessary during GC/MS analysis. Additionally, by utilizing this novel method, any concerns about beta-blocker metabolite and/or sample matrix interference are eliminated. The limits of detection for this method ranged from 0.39 to 0.78 ng/mL and the linear dynamic range was generally 1.6-3200 ng/mL. The extraction efficiencies for each analyte ranged from 58% to 82%. This method was successfully applied to postmortem fluid and tissue specimens obtained from victims of three separate aviation accidents. 相似文献
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This study explored the similarities and differences of the perceptions held by chief legal and chief student affairs officers with regard to student legal issues. The study follows an earlier project published by Education and the Law (9(1), pp. 41‐49) which solely examined the perceptions of chief legal affairs officers. In the present study, there was a significant difference in the perceptions of chief student affairs and chief legal affairs officers with regard to which student legal issues will be litigated in the next 10 years. Chief student affairs and chief legal affairs officers prepare for student legal issues in a very similar fashion. Both officers make use of legal conferences, student affairs conferences, continuing education, and professional literature. There appears to be many chief student affairs officers who attend legal conferences and chief legal affairs officers who attend student affairs conferences in order to better prepare for future student legal issues. 相似文献
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