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71.
Since 1999, dozens of organizations and hundreds of initiatives have emerged to improve the quality and safety of patient care, yet insufficient progress has been made. Attention has turned toward improving senior leadership team effectiveness. The authors describe a national project that examined the role of the senior leadership team in 8 hospitals in promoting quality and safety, with particular focus on the role of the chief nurse officer in this process.  相似文献   
72.
Bolus tracking magnetic resonance imaging (MRI) is a powerful technique for assessing cerebral perfusion, but its capability to measure absolute cerebral blood flow (CBF) and volume (CBV) values is still debated. To validate the MRI technique, absolute CBF and CBV values in healthy humans obtained by echo planar gradient echo MRI were compared to H(2)(15)O and (11)CO positron emission tomography (PET) before and after acetazolamide (ACZ) (n = 8) or saline (n = 4) administration. The repeatability of CBF and CBV measurements was moderate with both methods, and slightly lower with MRI than with PET. At rest, the mean CBF values were similar with both techniques except in the cortex where they were moderately higher with MRI. CBV was higher with MRI than with PET in all areas, which may reflect an underestimation of the arterial input function (AIF). After ACZ, a significant CBF increase was observed in gray matter with both MRI and PET, suggesting that MRI might be used to assess the cerebrovascular reserve. In individual subjects, the correlation between MRI and PET measurements was good for both CBF and CBV (R(2) between 0.70 and 0.84). However, when all results were considered as a group, R(2) was lower (0.40 to 0.65), and the limits of agreement between the two methods (SD of the difference) were large. Our data suggest that physiologic CBF values and systematically overestimated CBV values may be obtained with MRI in healthy humans, but that an individual scale factor should be applied to MRI measurements to improve the agreement with PET.  相似文献   
73.
Combinations of tests comprising alpha2-macroglobulin, haptoglobin, apolipoprotein Al, gamma-glutamyltransferase, total bilirubin (Fibrotest) and alanine aminotransferase (Actitest) are being developed as alternatives to liver biopsy in patients with chronic hepatitis C. The aim of this study was to assess in the same laboratory the impact of parameter assay variations on Fibrotest and Actitest results and intra-patient reproducibility of the two tests. The stability of the samples for each test was studied after storage at -80 degrees C and -20 degrees C. Within-run, between-run and total imprecision for each parameter assay, and for Fibrotest and Actitest results, were determined. Transferability of assay results between different analyzers was studied. Intra-patient reproducibility was assessed in 55 hospitalized patients. Fibrotest and Actitest reference ranges were determined in 300 blood donors (reference group). The stability of the parameters was affected by serum storage at -20 degrees C only. The impact of parameter analytical variability on Fibrotest and Actitest results was less than 10% and intra-patient reproducibility was acceptable (p > 0.05). The transferability between different analyzers of results of assays performed under the same standardized and calibration conditions was excellent. Fibrotest and Actitest reference ranges in blood donors were (mean+/-SE) 0.075+/-0.004 and 0.068+/-0.004, respectively. The low intra-laboratory and intra-patient variability in Fibrotest and Actitest results confirm Fibrotest and Actitest reliability.  相似文献   
74.
Fatigue is very common in patients with cancer. Current guidelines suggest that psychostimulants are "reasonable to consider for severe fatigue." This randomized, double-blind, placebo-controlled trial investigated the hypothesis that dexamphetamine in fatigued patients with advanced cancer would produce a clinically significant improvement with minimal side effects. Fifty patients with advanced cancer, who were receiving palliative care, were randomized to dexamphetamine 10mg twice daily or placebo for eight days. Effectiveness was assessed using the Brief Fatigue Inventory and the McGill Quality-of-Life Questionnaire. The side effects were recorded. The results were analyzed on an intention-to-treat basis. The baseline demographics, fatigue levels, and quality-of-life scores were similar between the two arms. Patients were elderly, had impaired performance status (Eastern Cooperative Oncology Group score=3), and were taking a range of neurologically active medications. Thirty-nine patients completed the trial. There was a transient improvement in the fatigue levels on day 2, but no significant difference in fatigue (P=0.267) or quality of life (P=0.579) by the end of the study. Statistical modeling did not reveal any significant predictors of response to dexamphetamine. These results suggest that dexamphetamine 20mg daily, although well tolerated, does not significantly improve fatigue or quality of life in patients with advanced cancer, as measured by the selected instruments.  相似文献   
75.
As coronary artery disease (CAD) remains a leading cause of death in the world, the development of anti-coagulants to prevent CAD progressing to myocardial infarction and death is a high priority. A number of direct Factor Xa (FXa) inhibitors are being developed for use in CAD. Despite being developed to the stage of Phase II clinical trials, DX-9065a is no longer a priority with its developing company for further development, possibly because the Phase II trials did not show any major benefit of DX-9065a over heparin in subjects undergoing percutaneous coronary interventions (PCI) or with non-ST-elevation acute coronary syndromes (ACS). ZK-807834, otamixaban, apixaban, and rivaroxaban are all direct FXa inhibitors that have undergone preclinical and some clinical testing for use in CAD. In a large Phase II clinical trial of subjects with ACS, some doses of otamixaban had a better benefit/risk profile than the unfractionated heparin/eptifibatide combination. However, neither ZK-807834 nor otamixaban appear to be undergoing further clinical development at present. In ACS, placebo-controlled large Phase II clinical trials with apixaban and rivaroxaban have not shown clear cut benefits. Nevertheless, apixaban and rivaroxaban are presently in placebo-controlled Phase III clinical trials for ACS. Presently, there is no compelling evidence to support the use of direct FXa inhibitors in ACS.  相似文献   
76.
BACKGROUND: Various devices are now available to measure glycated haemoglobin (HbA1c) outside of the laboratory. The aim of this study was to assess the performance of these point-of-care instruments in the hands of non-laboratory trained personnel. METHODS: Two nursing staff tested samples from patients attending a diabetes research clinic using the following point-of-care devices for HbA1c-Metrica A1C Now, Bayer DCA 2000, Cholestech GDX and Axis-Shield Nycocard HbA1c. In addition they performed regular analysis of quality control samples. The effects on analytical performance of multiple operators as well as laboratory-trained staff, were also assessed. All measurements were compared to a boronate-affinity HPLC method in the central laboratory. RESULTS: The mean HbA1c difference of the point-of-care devices compared to the laboratory reference method ranged from -0.31% to +0.39%. Only the DCA device had a between batch imprecision of less than 5%. The analytical performance obtained by laboratory staff was similar to nursing staff for 3 devices and better for the Nycocard device. CONCLUSIONS: On the basis of the results obtained by nursing staff, only the DCA of the devices tested, can be recommended for measurement of HbA1c outside of the laboratory.  相似文献   
77.
78.
Respiratory compromise after rattlesnake envenomation (RSE) is an uncommon yet potentially lethal complication. We were interested in determining the frequency of respiratory compromise in patients treated for RSE. The incidence and indications for intubation were also determined. A retrospective chart review was conducted of all patients treated by medical toxicologists at a tertiary referral hospital between July, 1994 and November, 2000. Out of 294 total patients, 289 charts were reviewed. Of all 289 patients, 214 (74%) received Crotalidae Polyvalent Antivenin (Wyeth-Ayerst) and 23 (8%) had clinical evidence of respiratory compromise. Thirteen of 289 patients (4.4%) were intubated following RSE. No one was intubated for antivenin-induced complications. There were no deaths among studied patients during acute hospitalization. Respiratory compromise following RSE is rare, occurring in only 8% of studied patients. Only 2 patients (0.7%) required intubation as a direct consequence of RSE. No one required intubation for antivenin-induced hypersensitivity reactions.  相似文献   
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