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Julius HC  Beck K 《Hospital formulary》1992,27(6):638-40, 643
At a university teaching hospital, a study was undertaken to assess the frequency and appropriateness of restricted antibiotic use using a special drug request (SDR) form to collect the data. The usefulness of the SDR form itself was also assessed for its ability to provide valuable information about patient care and cost effectiveness. The results of this study are presented below.  相似文献   
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AIMS: The objectives of this study were to compare the efficacy of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in assessing the response of primary breast carcinoma to neoadjuvant chemotherapy compared to conventional imaging modalities, and to see how surgical outcome was influenced as a result of these findings. METHODS: Thirty-four patients with locally advanced primary breast cancer underwent conventional imaging and DCE-MRI following six cycles of neoadjuvant chemotherapy prior to surgery. Changes in surgical management based on the post-chemotherapy DCE-MRI findings were recorded. RESULTS: Prior to neoadjuvant chemotherapy, 22 of the 34 patients were assessed as requiring mastectomy and the remaining 12 were considered inoperable. Following chemotherapy two patients were still considered inoperable. In 11 of the 34 patients, the final decision to proceed to either mastectomy or non-surgical management was based primarily on pre-treatment disease status or patient choice. DCE-MRI findings, therefore, contributed to the operative decision in 21 of 34 patients. Two of these 21 patients were spared surgery as DCE-MRI demonstrated complete response to chemotherapy and one declined surgery. The remaining 18 were able to undergo wide local excision, with only two patients subsequently requiring mastectomy for involved margins. CONCLUSIONS: DCE-MRI is able to accurately predict those patients suitable for breast conserving surgery following neoadjuvant chemotherapy and should be the imaging modality of choice in assessing the response of patients with primary breast carcinoma to neoadjuvant chemotherapy.  相似文献   
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PurposeTo compare the cost-effectiveness of using doxorubicin-loaded drug-eluting embolic (DEE) transarterial chemoembolization versus that of using conventional transarterial chemoembolization for patients with unresectable hepatocellular carcinoma (HCC).Materials and MethodsA decision-analysis model was constructed over the lifespan of a payer’s perspective. The model simulated the clinical course, including periprocedural complications, additional transarterial chemoembolization or other treatments (ablation, radioembolization, or systemic treatment), palliative care, and death, of patients with unresectable HCC. All clinical parameters were derived from the literature. Base case calculations, probabilistic sensitivity analyses, and multiple two-way sensitivity analyses were performed.ResultsIn the base case calculations for patients with a median age of 67 years (range for conventional transarterial chemoembolization: 28–88 years, range for DEE-transarterial chemoembolization: 16–93 years), conventional transarterial chemoembolization yielded a health benefit of 2.11 quality-adjusted life years (QALY) at a cost of $125,324, whereas DEE-transarterial chemoembolization yielded 1.71 QALY for $144,816. In 10,000 Monte Carlo simulations, conventional transarterial chemoembolization continued to be a more cost-effective strategy. conventional transarterial chemoembolization was cost-effective when the complication risks for both the procedures were simultaneously varied from 0% to 30%. DEE-transarterial chemoembolization became cost-effective if the conventional transarterial chemoembolization mortality exceeded that of DEE-transarterial chemoembolization by 17% in absolute values. The two-way sensitivity analyses demonstrated that conventional transarterial chemoembolization was cost-effective until the risk of disease progression was >0.4% of that for DEE-transarterial chemoembolization in absolute values. Our analysis showed that DEE-transarterial chemoembolization would be more cost-effective if it offered >2.5% higher overall survival benefit than conventional transarterial chemoembolization in absolute values.ConclusionsCompared with DEE-transarterial chemoembolization, conventional transarterial chemoembolization yielded a higher number of QALY at a lower cost, making it the more cost-effective of the 2 modalities.  相似文献   
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Structural reorganization in white matter (WM) after stroke is a potential contributor to substitute or to newly establish the functional field on the injured brain in nature. Diffusion tensor imaging (DTI) is an imaging modality that can be used to evaluate damage and recovery within the brain. This method of imaging allows for in vivo assessment of the restricted movements of water molecules in WM and provides a detailed look at structural connectivity in the brain. For longitudinal DTI studies after a stroke, the conventional region of interest method and voxel‐based analysis are highly dependent on the user‐hypothesis and parameter settings for implementation. In contrast, tract‐based spatial statistics (TBSS) allows for reliable voxel‐wise analysis via the projection of diffusion‐derived parameters onto an alignment‐invariant WM skeleton. In this study, spatiotemporal WM changes were examined with DTI‐derived parameters (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, DA; radial diffusivity, RD) using TBSS 2 h to 6 weeks after experimental focal ischemic stroke in rats (N = 6). FA values remained unchanged 2–4 h after the stroke, followed by a continuous decrease in the ipsilesional hemisphere from 24 h to 2 weeks post‐stroke and gradual recovery from the ipsilesional corpus callosum to the external capsule until 6 weeks post‐stroke. In particular, the fibers in these areas were extended toward the striatum of the ischemic boundary region at 6 weeks on tractography. The alterations of the other parameters in the ipsilesional hemisphere showed patterns of a decrease at the early stage, a subsequent pseudo‐normalization of MD and DA, a rapid reduction of RD, and a progressive increase in MD, DA and RD with a decreased extent in the injured area at later stages. The findings of this study may reflect the ongoing processes on tissue damage and spontaneous recovery after stroke.  相似文献   
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Background: Previous research using functional MRI (fMRI) suggests changes in cortical activation as a function of increased task difficulty. This relationship has not been explored in persons with aphasia even though it may have significant implications for pre- and post-treatment interpretation of fMRI data.Aims: The purpose of this exploratory study was to investigate the relationship between changes in language task difficulty and cortical activation in persons with aphasia.Methods & Procedures: Four persons with chronic anomic or Broca's aphasia and four matched control participants underwent fMRI while performing a picture–word matching task.Outcomes & Results: Compared to the more difficult task condition, all participants performed with greater accuracy on the easier condition. Moreover, greater mean blood oxygenated level dependent (BOLD) signal intensity and area recruitment were noted during the more difficult condition for three out of four persons with aphasia as well as three of the four controls. The increase in cortical activity was mainly noted in the superior temporal and posterior inferior frontal lobes.Conclusions: The present findings mirror those found in previous studies of normal subjects in that cortical activation increased in parallel to task difficulty for most of our participants. It is unclear what mechanism accounts for this effect; this phenomenon might need to be considered in future fMRI studies of neural plasticity associated with aphasia treatment.  相似文献   
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