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Postoperative pain control is a clinical imperative, for which morphine is a preferred opioid. However, interpatient variability and drug accumulation with repeated doses, as well as medication errors, may result in respiratory arrest with this medication. Early detection of respiratory depression is essential for safe use of morphine, following both initial and repeated doses. A multidisciplinary team contributed to development of an intravenous (IV) bolus morphine monitoring guideline that reflects current knowledge of morphine pharmacokinetics. Monitoring over a 22-week period in a postsurgical unit was then assessed via record review. A total of 270 postsurgical patients received a first dose of IV bolus morphine, with 784 subsequent doses also administered. Complete monitoring (heart rate, respiratory rate, blood pressure, sedation score, oxygen saturation, and pain score) after the morphine bolus was documented at baseline and 10 and 20 minutes for 34%, 30%, and 23%, respectively, of the patients; partial monitoring (respiratory rate and oxygen saturation) was documented for an additional 22%, 15%, and 9% of patients; 43% of subsequent morphine doses were followed with complete monitoring, and an additional 30% with at least partial monitoring. Adherence to the monitoring procedure fluctuated over the study period with no consistent upward or downward trend. A small number of children exhibited a reduced respiratory rate potentially indicating respiratory depression, but no child required antidote or respiratory support. Despite suboptimal guideline adherence, potential signs of respiratory depression were detected that might otherwise have gone unnoticed. This validates the improved guideline and suggests that some incidents may have remained undetected. Front-line staff must be involved to optimize change, champion the initiative, and promote patient safety.  相似文献   
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We evaluated the diagnostic performance of 18F‐FDG PET/CT and MRI for the assessment of head and neck squamous cell carcinoma (HNSCC) relapse. Since early treatment might prevent inoperable relapse, we also evaluated THE performance of early unenhanced 18F‐FDG PET/CT in residual tumor detection. The study was prospectively performed on 32 patients who underwent 18F‐FDG PET/CT and MRI before treatment and at 4 and 12 months after treatment. 18F‐FDG PET/CT was also performed 2 weeks after the end of radiotherapy. Histopathology or a minimum of 18 months follow‐up were used as gold standard. Before treatment 18F‐FDG PET/CT and MRI detected all primary tumors except for two limited vocal fold lesions (sensitivity 94%). MRI was more sensitive than 18F‐FDG PET/CT for the detection of local extension sites (sensitivity 75 vs 58%), but at the cost of a higher rate of false positive results (positive predictive value 74 vs 86%). For relapse detection at 4 months, sensitivity was significantly higher for 18F‐FDG PET/CT (92%) than for MRI (70%), but the diagnostic performances were not significantly different at 12 months. For the detection of residual malignant tissue 2 weeks post‐radiotherapy, sensitivity and specificity of 18F‐FDG PET/CT were respectively 86 and 85% (SUV cut‐off value 5.8). 18F‐FDG PET/CT is effective in the differentiation between residual tumor and radiation‐induced changes, as early as 2 weeks after treatment of a primary HNSCC. For follow‐up, performance of 18F‐FDG PET/CT and MRI are similar except for a higher sensitivity of 18F‐FDG PET/CT at 4 months. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Superparamagnetic iron oxide nanoparticles (SPION) are very promising contrast media, especially for molecular imaging, due to their superior NMR efficacy. They even have wider biomedical applications such as in drug and gene delivery, tissue engineering and bioseparation, or as sensitive biological nanosensors. By coupling them to affinity ligands, SPION can bind to drugs, proteins, enzymes, antibodies or nucleotides. For in vitro biomedical applications, the detection of molecular interaction is possible by using a diversity of systems capable of sensing the magnetic properties of these materials. The goal of the present work was to develop and validate various in vitro biomedical applications of ultrasmall superparamagnetic particles of iron oxide (USPIO), including some that are not related to their magnetic properties. USPIO coated with dextran, starch or bisphosphonate exposing carboxylate groups were synthesized and some of them were functionalized by conjugating various biomolecules, such as biotin, streptavidin and apoptosis, or VCAM‐1 specific peptides. The in vitro biomedical applications assessed in the present work included: (1) the relaxometric measurement of antibody concentration, cell receptor expression, molecular interaction, and enzymatic activity in aqueous suspensions; (2) MRI visualization of cells and detection of molecular interaction in an ELISA system; (3) ELISA applications of USPIO derivatives; and (4) detection of specific biomolecules by histochemistry. Our results confirm that rapid and simple in vitro detection of a diversity of functionalized SPION with relevance in medicine is possible by the existing NMR techniques and by chemical staining reactions. The protocols can be applied to minimally prepared biological samples (e.g. whole blood, blood plasma or serum, cell suspensions, biopsies, histological preparations, etc.), and often do not need complicated systems of signal amplification. The use of SPION labeled compounds could furthermore contribute to cost reductions in the diagnosis and in patient care. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Background  

This study aimed to describe the differences in the management of symptomatic gallstone disease within different elderly groups and to evaluate the association between older age and surgical treatment.  相似文献   
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Journal of Neurology - Symptomatic isolated carotid artery occlusions (ICAO) can lead to disability, recurrent stroke, and mortality, but natural history and best therapeutic management remain...  相似文献   
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