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101.
Gross PA Patriaco D McGuire K Skurnick J Teichholz LE 《The Joint Commission journal on quality improvement》2002,28(10):566-573
BACKGROUND: Telemetry monitoring is widely used in hospitals; the importance of being able to monitor and examine dysrhythmias has been universally accepted. Yet it is often used for patients who do not actually require this technology. A model to improve the efficiency of telemetry use entailed the use of an advanced practice nurse (APN; identical to a nurse practitioner) to provide concurrent review and intervention of floating telemetry, which is available for patients independently of the floor location and who do not need an intensive care unit bed. ADDRESSING OVERUSE: The demand for floating telemetry at Hackensack University Medical Center had equaled or exceeded the telemetry availability virtually 100% of the time, even after local guidelines had been disseminated in 1998. The APN carried out concurrent monitoring and intervened with the attending physician when patients were on telemetry for longer than 48 hours and did not meet the local telemetry guidelines. RESULTS: The mean number (standard error [SE]) of hours per patient declined from 65.2 +/- 0.7 hours (95% confidence interval, 63.8 to 66.6 hours) for the 11 months before the intervention to a mean of 49.6 +/- 0.4 hours (95% confidence interval, 48.7 to 50.2 hours) for the 29 months after intervention--representing a decrease of 34% (p < 0.0001). This decrease led to an increase in the number of patients per month put on telemetry. DISCUSSION: The APN model, an aggressive approach that induced change almost immediately, was then applied to other quality improvement projects. 相似文献
102.
Gross PA 《The Joint Commission journal on quality improvement》2000,26(9):547-553
BACKGROUND: A roundtable held October 5-6 1999, in Maidstone, Kent, United Kingdom, was convened to identify current strategies and ongoing challenges in implementing evidence-based practice guidelines in health care. Despite numerous new medical research findings for improving health care and despite the dissemination of many practice guidelines, the recommendations from these efforts are not being uniformly adopted. Overuse, underuse, and misuse plague the practice of medicine today. IMPLEMENTING GUIDELINES: Multiple implementation strategies are more likely to succeed that a single implementation method; local selection and adaptation of guidelines are critical; and reminders, educational outreach (for prescribing), and interactive educational workshops are generally effective. EXPERIENCE IN EUROPE: In most countries, guideline development has progressed from consensus conference, to evidence-based statements, and finally to evidence-based guidelines that also consider cost-effectiveness. Guideline development is the most advanced in The Netherlands, where physicians have coordinated their efforts with the government to achieve more uniformity than is found elsewhere. EXPERIENCE IN THE UNITED STATES: Designing systems that will facilitate change--not changing physician behavior--should be the focus. The concern for effecting improvement in health care is now more acute because of the increased attention being given to medical errors and patient safety. SUMMARY STATEMENT: Multifaceted approaches are clearly the most important method for improving care. Such approaches may include many improvement methods, none of which work well alone most of the time or any of the time. 相似文献
103.
Increased prevalence of Alzheimer's disease-like beta-amyloid deposits in the neuropil and within neurons occurs in the brains of non-demented individuals with heart disease. Heart disease is a prevalent finding in Alzheimer's disease, and may be a forerunner to the dementing disorder. In the cholesterol-fed rabbit model of human coronary heart disease there is production and accumulation of beta-amyloid in the brain. This accumulation of beta-amyloid can be reversed by removing cholesterol from the rabbits' diet. In culture cells, a cholesterol challenge has been shown to increase production of beta-amyloid, and dramatic reductions of cholesterol produced by HMG Co-A reductase inhibitors decrease production of beta-amyloid. Increased beta-amyloid production is also produced by dietary cholesterol in a number of transgenic mouse models of Alzheimer's disease. Administration of HMG Co-A reductase inhibitors may block beta-amyloid production caused by dietary cholesterol in rabbits. Clinical trials testing the benefit of HMG Co-A reductase inhibitors in the treatment of Alzheimer's disease are underway. 相似文献
104.
D. Bruns B. Büchner R. Gross T. Lorenz S. Uchida 《Journal of Low Temperature Physics》1999,117(5-6):1453-1457
We present thermal expansion measurements on a La1.85Sr0.15CuO4
single crystal in external magnetic fields. Clear anomalies of the thermal expansion are observed at the superconducting transition. We have studied in detail the anisotropic influence of external fields on the anomalies. As expected, the field dependence is maximum for B c and minimum for B c. The measured angular dependence corresponds to that of an anisotropic 3d superconductor with an anisotropy parameter 18. 相似文献
105.
We investigated the contribution of the liver and gut to systemic diphenhydramine (DPHM) clearance in adult nonpregnant sheep in two separate studies. In the first study, a simultaneous 50-mg bolus each of DPHM and its deuterium-labeled analog ([2H10]DPHM) was administered to five sheep via the femoral (i.v.) and the portal venous (p.v.) routes in a randomized manner. Arterial plasma concentrations of DPHM, [2H10]DPHM, and their deaminated metabolites, DPMA (diphenylmethoxyacetic acid) and [2H10]DPMA, were measured using gas chromatography-mass spectrometry. The hepatic first-pass extraction of DPHM after p.v. administration was 94.2 +/- 3.7%. However, the area under the plasma concentration versus time profile of the metabolite after i.v. dosing was only 32.5 +/- 14.0% relative to that after p.v. administration. Thus, only approximately 32.5% of the i.v. dose is metabolized in the liver and a significant extrahepatic systemic clearance component is evident. Using the calculated total hepatic blood flow values, it was found that 98.6 +/- 9.2% of the i.v. dose eventually was delivered to the "hepatoportal" system. Because the drug delivered to the hepatoportal system is almost completely eliminated in a single pass (hepatic extraction approximately 94%), this indicates a lack of any significant pulmonary drug uptake. Also, because only approximately 32.5% of the i.v. dose is metabolized in liver, the gut is most likely responsible for the clearance of the remainder. This gut contribution to systemic DPHM clearance was confirmed in a separate direct study in four sheep where the steady-state DPHM gut extraction ratio was 49.0 +/- 3.0%. Thus, gut accounts for a significant proportion (>/=50%) of DPHM systemic clearance in sheep in spite of a very high hepatic drug extraction efficiency. 相似文献
106.
In vivo local determination of tissue optical properties: applications to human brain 总被引:10,自引:0,他引:10
Bevilacqua F Piguet D Marquet P Gross JD Tromberg BJ Depeursinge C 《Applied optics》1999,38(22):4939-4950
Local and superficial near-infrared (NIR) optical-property characterization of turbid biological tissues can be achieved by measurement of spatially resolved diffuse reflectance at small source-detector separations (<1.4 mm). However, in these conditions the inverse problem, i.e., calculation of localized absorption and the reduced scattering coefficients, is necessarily sensitive to the scattering phase function. This effect can be minimized if a new parameter of the phase function gamma, which depends on the first and the second moments of the phase function, is known. If gamma is unknown, an estimation of this parameter can be obtained by the measurement, but the uncertainty of the absorption coefficient is increased. A spatially resolved reflectance probe employing multiple detector fibers (0.3-1.4 mm from the source) is described. Monte Carlo simulations are used to determine gamma, the reduced scattering and absorption coefficients from reflectance data. Probe performance is assessed by measurements on phantoms, the optical properties of which were measured by other techniques [frequency domain photon migration (FDPM) and spatially resolved transmittance]. Our results show that changes in the absorption coefficient, the reduced scattering coefficient, and gamma can be measured to within +/-0.005 mm(-1), +/-0.05 mm(-1), and +/-0.2, respectively. In vivo measurements performed intraoperatively on a human skull and brain are reported for four NIR wavelengths (674, 811, 849, 956 nm) when the spatially resolved probe and FDPM are used. The spatially resolved probe shows optimum measurement sensitivity in the measurement volume immediately beneath the probe (typically 1 mm(3) in tissues), whereas FDPM typically samples larger regions of tissues. Optical-property values for human skull, white matter, scar tissue, optic nerve, and tumors are reported that show distinct absorption and scattering differences between structures and a dependence on the phase-function parameter gamma. 相似文献
107.
108.
D Antonelli T Rosenfeld NA Freedberg E Palma JN Gross S Furman 《Canadian Metallurgical Quarterly》1998,21(2):418-421
Gag gene mutants of human immunodeficiency virus type 1 (HIV-1) were analyzed for their potentials of inhibiting the replication of wild-type (wt) HIV-2, the second AIDS virus, in a single-round of viral replication. Of twenty-two HIV-1 gag mutants examined, seven were found to efficiently interfere with the replication of wt HIV-2. Some mutants, which can suppress the replication of wt HIV-1, did not show this inhibitory effect. These mutants were defective at the late phase of viral replication. A mutant designated NL-C1a was demonstrated to be very effective against the replication of HIV-1 and HIV-2 in monocytic cells as well as in lymphocytic cells. 相似文献
109.
110.
PURPOSE: The aim of this study was to classify the human IgG autoantibody repertoire of sera from patients suffering from endocrine ophthalmopathy (EOP) and healthy subjects (CTRL) for diagnostic purposes using the recently developed Megablot technique. This technique allows for the simultaneous and quantitative screening of a large set of antigens and uses multivariate statistical techniques and an artificial neural network. METHODS: Sera were tested against Western blots (WBs) of SDS-PAGE preparations of proteins from human extraorbital eye muscle (EOP: n = 16; CTRL: n = 11). Digital image analysis was performed. The blots were subsequently analyzed by multivariate statistical techniques (analysis of discriminance) and an artificial neural network (probalistic neural network). RESULTS: The sera of both the EOP and CTRL groups showed a complex staining pattern against WBs of SDS-PAGEs from human eye muscle. Using the multivariate statistical technique for classification, all of the known samples and 85% of the unknown samples (not presented during calculation) were assigned to their correct clinical group. Using the artificial neural network as classifier, all of the samples presented during training and 96.3% of the unknown samples (not trained) were assigned correctly. CONCLUSIONS: The artificial neural network exceeds the ability of multivariate statistical techniques such as analysis of discriminance to assign unknown samples to their correct predefined group. Thus, the neural network exceeds other methods in generalizing some similarities of blots used for classification. This study reveals that our new technique and its evaluation using a neural network can be used as a helpful diagnostic tool in autoimmune diseases such as endocrine ophthalmopathy. 相似文献