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991.
Tetrabenazine (TBZ), a presynaptic dopamine depletor and postsynaptic dopamine receptor blocker, is widely used for the treatment of hyperkinetic movement disorders in adults. However, reports of its use in children are limited. We review the efficacy and tolerability of TBZ therapy in 31 children with hyperkinetic movement disorders refractory to other medications. TBZ was effective in reducing the severity of movement disorders resistant to treatment with other medicines. When compared to adult patients, pediatric patients required higher doses. Side effects were similar to the adult population; however, children had a lower incidence of drug-induced Parkinsonism.  相似文献   
992.
993.
994.
Acute respiratory distress syndrome (ARDS) is characterized by perfusion in favor of non-ventilated areas of the lungs as the main cause of intrapulmonary right-to-left shunt and hypoxemia. Therapeutic interventions to selectively influence pulmonary perfusion in ARDS became possible with the introduction of inhaled nitric oxide (iNO), which provided a way not only to reduce pulmonary hypertension, but also to acutely improve ventilation-perfusion mismatch, and thus to treat severe hypoxemia. Clinical studies in ARDS demonstrated that the combination of iNO with other interventions, such as positive end-expiratory pressure (PEEP) and prone positioning, yielded beneficial and additive effects on arterial oxygenation. Although randomized controlled trials of this concept have up to now failed to show an improved outcome, iNO is a valuable option for the treatment of severe refractory hypoxemia in ARDS patients.  相似文献   
995.
Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV1) to decide when to initiate combination treatment with a long-acting β2-agonist and an inhaled corticosteroid. Assessment of baseline FEV1 as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV1 <50% and FEV1 ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV1; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV1 <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV1; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV1, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials.  相似文献   
996.
We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors.  相似文献   
997.
998.
Anthracycline cardiotoxicity.   总被引:3,自引:0,他引:3  
Anthracycline drugs have been widely used as chemotherapeuticagents against a range of cancers, including sarcomas, carcinomas,leukaemias, and lymphomas. However, cardiotoxic effects, inparticular the development of cardiomyopathy, have limited theirclinical use. The observation of dose-dependent cardiotoxicityhas resulted in a recommended empirical dose limit of 450 mg/m2of body surface area. Age, gender, pre-existing heart disease,hypertension, and mediastinal irradiation have also been implicatedas factors contributing to the development of doxorubicin-associatedcardiomyopathy. However, cardiotoxicity may still occur at relativelylow levels of drug administration, even in individuals withno additional risk factors, and the onset may be delayed bymany years.1 More recently, the use of trastuzumab, a monoclonalantibody directed against the HER2 receptor, has been  相似文献   
999.
The purpose of this study was to enhance our understanding of the influence of the SARS crisis on the work and personal lives of community nurses.A total of 941 community nurses employed in a range of health-care settings in the province of Ontario, Canada, provided qualitative information about their perceptions of the impact of SARS in their workplace and in their personal lives. Themes and subthemes from the data were organized into 2 categories: The Experience (operational, organizational, and personal narratives), and Learning from the Experience (opportunities for personal learning, professional and policy development, and insight into policy and administrative implications). The findings are discussed within a framework of the learning opportunity presented by the crisis at the local, national, and international levels. The roles of effective communication, emergency response coordination, and education are considered with respect to policy development and administrative responses to infectious disease protocol. The findings are particularly relevant at this time of heightened fear of global epidemics.  相似文献   
1000.
PURPOSE: To evaluate rates, predictors, and barriers to use of the Internet to obtain cancer information among a cohort of cancer patients at an urban county hospital. PATIENTS AND METHODS: Of 208 cancer patients approached, 200 patients completed a structured interview study examining Internet use, perceptions of the accuracy of Internet information, and barriers to use. RESULTS: Only 10% of participants reported using the Internet themselves to obtain cancer information. Another 21% reported exposure to Internet information through proxies. The most common barrier to Internet use cited was lack of Internet access, with 44% reporting that they would use the Internet to obtain cancer information if they had Internet access. Younger age and more years of formal education were significantly associated with Internet use, although race and income were not. Less education, African American race, and female sex were associated with lower estimates of the accuracy of Internet information. Fewer years of formal education was associated with increased likelihood of reporting confusion after reading Internet information. CONCLUSION: Very few cancer patients in this study of a cohort of generally disadvantaged individuals used the Internet themselves to obtain cancer information, although many more desired to do so. Significant opportunities for Web-based interventions aimed at improving cancer care outcomes in this population of cancer patients exist. However, further study will be needed to determine how to make such intervention accessible, trustworthy, and understandable to the disadvantaged.  相似文献   
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