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991.
The zeitgeist of the new radiology workforce can best be described by a Bob Dylan song title: “The Times They Are A-Changin’.” The new generation of physicians, although embracing the same foundations of medical practice as previous generations, places greater emphasis on personal satisfaction than its predecessors. Gone are the days when physicians operated as sole practitioners; today’s workforce member is content to function in the role of “employee” in a trade-off for more lifestyle flexibility. This change has occurred not because of one specific factor but because of a change in the profession of medicine coupled with a combination of factors; familial responsibilities, avocational activities, and personal satisfaction have surfaced as motivating factors in choosing a profession. Today’s workforce has a personal perception of success that may not be fulfilled solely by the contemporary practice of medicine. With the radiologist shortages that are now occurring and anticipated increased demand for staff radiologists, today’s radiology workforce has helped shape the specialty into one that is altering its structure to attract and retain its workforce. 相似文献
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Siberian ginseng (Eleutheroccus senticosus) effects on CYP2D6 and CYP3A4 activity in normal volunteers. 总被引:3,自引:0,他引:3
Jennifer L Donovan C Lindsay DeVane Kenneth D Chavin Robin M Taylor John S Markowitz 《Drug metabolism and disposition》2003,31(5):519-522
Siberian ginseng ([SG]; Eleutherococcus senticosus) is a commonly used herbal preparation. The objective of this study was to assess in normal volunteers (n = 12) the influence of a standardized SG extract on the activity of cytochrome P450 CYP2D6 and 3A4. Probe substrates dextromethorphan (CYP2D6 activity) and alprazolam (CYP3A4 activity) were administered orally at baseline and again following treatment with SG (1 x 485 mg twice daily) for 14 days. Urinary concentrations of dextromethorphan and dextorphan were quantified, and dextromethorphan metabolic ratios (DMRs) were determined at baseline and after SG treatment. Likewise, plasma samples were collected (0-60 h) for alprazolam pharmacokinetics at baseline and after SG treatment to assess effects on CYP3A4 activity. Validated high performance liquid chromatography methods were used to quantify all compounds and relevant metabolites. There were no statistically significant differences between pre- and post-SG treatment DMRs indicating a lack of effect on CYP2D6 (P > 0.05). For alprazolam there also were no significant differences in the pharmacokinetic parameters determined by noncompartmental modeling (C(max), T(max), area under the curve, half-life of elimination) indicating that SG does not significantly induce or inhibit CYP3A4 (P > 0.05). Our results indicate that standardized extracts of SG at generally recommended doses for over-the-counter use are unlikely to alter the disposition of coadministered medications primarily dependent on the CYP2D6 or CYP3A4 pathways for elimination. 相似文献
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John N Burry 《British medical journal》2003,327(7425):1228