ABSTRACT
Objective: To establish the determination method for meropenem in urine by fluorescence resonance energy transfer spectroscopy. Methods:An LS-55 fluorescence spectrophotometer was used. The solution of meropenem, fluorescein, eosin Y, BR buffer and cetyl trimethyl ammonium bromide was respectively added into a 10 ml colorimetric tube. At λex of 455 nm and λem of 547 nm, the fluorescence intensity F and F0 of the system and the reagent blank sample was detected. Using ΔF = F-F0 as signal re-sponse value for meropenem, the content was calculated. Results: The linear regression equation of meropenem in urine was as fol-lows:ΔF=33. 8C+53. 4 (r=0. 991 7), the linear range was 0. 5-10 μg·ml-1 with the detection limit of 0. 13 μg·ml-1, the re-covery of 98. 9%-103. 0% and RSD of 0. 3%-0. 4%. Conclusion:The method is rapid and accurate, which can be used in the phar-macokinetic study of meropenem.
ABSTRACT
<p><b>OBJECTIVE</b>To construct a three-dimensional finite element model of the upper airway and adjacent structure of an obstructive sleep apnea hypopnea syndrome (OSAHS) patient for biomechanical analysis. And to study the influence of glossopharyngeum of an OSAHS patient with three-dimensional finite element model during titrated mandible advancement.</p><p><b>METHODS</b>DICOM format image information of an OSAHS patient's upper airway was obtained by thin-section CT scanning and digital image processing were utilized to construct a three-dimensional finite element model by Mimics 10.0, Imageware 10.0 and Ansys software. The changes and the law of glossopharyngeum were observed by biomechanics and morphology after loading with titrated mandible advancement.</p><p><b>RESULTS</b>A three-dimensional finite element model of the adjacent upper airway structure of OSAHS was established successfully. After loading, the transverse diameter of epiglottis tip of glossopharyngeum increased significantly, although the sagittal diameter decreased correspondingly. The principal stress was mainly distributed in anterior wall of the upper airway. The location of principal stress concentration did not change significantly with the increasing of distance. The stress of glossopharyngeum increased during titrated mandible advancement.</p><p><b>CONCLUSION</b>A more precise three-dimensional finite model of upper airway and adjacent structure of an OSAHS patient is established and improved efficiency by Mimics, Imageware and Ansys software. The glossopharyngeum of finite element model of OSAHS is analyzed by titrated mandible advancement and can effectively show the relationship between mandible advancement and the glossopharyngeum.</p>