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Early and late prognosis after percutaneous balloon aortic valvuloplasty (PBAV) was assessed in 38 consecutive elderly patients (mean age, 78.5 +/- 6.1 years). Significant valve opening was achieved in 35 patients. The hospital mortality was 8% (three patients); two other patients died within the first month and three underwent aortic valve replacement. At 2 years follow-up, there were 10 additional deaths (seven cardiac deaths) and five patients had symptom recurrence managed by aortic valve replacement (3) or repeat PBAV (2). Overall, six patients underwent surgery without untoward events and six had repeat PBAV. Only two out of six patients with repeat PBAV had sustained improvement; one was referred to surgery and the remaining three died soon after the second PBAV. One- and 2-year survival were respectively 72 and 62% and percentage of survivors with persistent improvement 68 and 41%. Although aortic valve area after PBAV was associated with outcome, predictors of poor long-term prognosis were primarily related to the pre-operative haemodynamic status. Patients with pulmonary resistances greater than 400 dynes cm-1 s-5 had the poorest outcome (chi 2 = 18.4-P less than 0.0001). Overall, signs of heart failure were predictors of poor long term follow-up. These data indicate that long-term success of PBAV is mainly related to the left ventricular dysfunction noted prior to intervention.  相似文献   
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We report the case of a child presenting with abdominal Burkitt's lymphoma in whom a relapse presented as orbital and muscle involvement. This clinical feature is extremely rare. Two muscle and one orbital biopsies were necessary to obtain proper diagnosis. A new extension check-up showed bone marrow invasion and normal cerebrospinal fluid. This relapse was successfully treated by conventional chemotherapy and consolidated with high-dose chemotherapy, total body irradiation and autologous bone marrow transplantation. Eighteen months after transplantation, the child may be considered as definitively cured.  相似文献   
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In 1998, the New York City Department of Health and the Mayor’s Office of Emergency Management began monitoring the volume of ambulance dispatch calls as a surveillance tool for biologic terrorism. We adapted statistical techniques designed to measure excess influenza mortality and applied them to outbreak detection using ambulance dispatch data. Since 1999, we have been performing serial daily regressions to determine the alarm threshold for the current day. In this article, we evaluate this approach by simulating a series of 2,200 daily regressions. In the influenza detection implementation of this model, there were 71 (3.2%) alarms at the 99% level. Of these alarms, 64 (90%) occurred shortly before or during a period of peak influenza in each of six influenza seasons. In the bioterrorism detection implementation of this methodology, after accounting for current influenza activity, there were 24 (1.1%) alarms at the 99% level. Two occurred during a large snowstorm, 1 is unexplained, and 21 occurred shortly before or during a period of peak influenza activity in each of six influenza seasons. Our findings suggest that this surveillance system is sensitive to communitywide respiratory outbreaks with relatively few false alarms. More work needs to be done to evaluate the sensitivity of this approach for detecting nonrespiratory illness and more localized outbreaks.  相似文献   
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The major cause of death from carotid artery surgery (1.2% in 1984 in this series) is still coronary disease and myocardial infarct. A series of 50 patients were randomly selected for detailed study of post-operative cardiologic complications and the following sequelae were noted: mortality = 1 myocardial infarct; morbidity = 1 myocardial infarct, 3 documented anginal pains, 8 repolarization disorders, 4 benign ventricular arrhythmias. Analysis of these complications and a literature review demonstrated: the high frequency of combined carotid artery and coronary artery stenosis even in asymptomatic patients (25 to 40% of cases); the elevated percentage of complications in patients with symptomatic coronary disease (mortality risk multiplied by ten), hypertension or arterial disease; the low effect of age taken alone as risk factor. Pre-operative explorations to detect angina, particularly when latent and asymptomatic, should include a questionnaire, strict patient clinical examination and detailed reading of electrocardiogram tracings. An effort test should be performed as a function of results and patients' medical history and when positive should lead to coronarography in patients under 70 in good general condition, and when doubt persists after the effort tests. The indication for surgical treatment is dependent on results of these explorations: Carotid artery surgery (stenosis with high cerebral risk) should be performed under pre- and post-operative myocardial protection in patients with coronary artery disease who are too old or inoperable for cardiac reasons. Simultaneous myocardial and cerebral revascularization in the presence of severe lesions and at equivalent risk of progression. First intention carotid artery surgery for bilateral stable lesions with subsequent simultaneous myocardial and cerebral revascularization. First intention carotid artery surgery in case of cerebral ischemia with coronary artery shunt surgery at a later stage. Improved exploration of patients and close cooperation between cardiologists, anaesthetists and surgeons should allow patients at high risk to be operated upon under improved conditions of safety.  相似文献   
6.
Idiopathic Parkinson's disease (PD) may possibly be caused by one or more unidentified neurotoxins present in the environment, or formed endogenously, which progressively damage dopaminergic nigrostriatal neurons. N-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is an experimental neurotoxin which produces biochemical and neuropathological changes in humans, lower primates and mice that closely resemble those found in PD. Because the mechanisms of neuronal damage in both idiopathic PD and in the MPTP model of PD may involve free radical formation in the substantia nigra, antioxidants might protect dopaminergic neurons. Previously, we found that both alpha-tocopherol and beta-carotene partially protected mice against MPTP. However, in the experiments described in this paper, neither alpha-tocopherol nor beta-carotene, each administered in massive doses, had any demonstrable protective effect for dopaminergic nigrostriatal neurons in marmosets injected with low doses of MPTP. Without more knowledge about the identity of the neurotoxin(s) causing idiopathic PD, and their mechanism of action, it is not possible at this time to predict whether these 2 antioxidants might be clinically useful in preventing or ameliorating PD.  相似文献   
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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   
10.
BACKGROUND: Observation and repeated examination may lead to favourable clinical outcomes in the ever-challenging diagnosis of appendicitis. The goal of this study was to evaluate clinical performance in the diagnosis of suspected appendicitis in a centre with limited access to medical imaging technologies and to identify factors associated with complicated cases. METHODS: A retrospective review of the medical records of 211 consecutive surgical cases of suspected appendicitis, spanning an 11-year period, was performed. The delays before treatment and the subsequent patient outcomes were evaluated. RESULTS: There were 8.1% of cases with negative findings on appendectomy, 75.8% with uncomplicated appendicitis, 12.3% with complicated appendicitis and 3.8% with other surgical conditions. The delay before the first medical consultation was significantly longer in patients with complicated appendicitis. The various delays after the first medical consultation did not differ significantly between the groups. CONCLUSIONS: In the context of limited available medical imaging modalities, clinical observation was not associated with an increased incidence of complicated appendicitis. The presence of complicated appendicitis was associated with the delay before the patient's first medical consultation. Clinical judgment can be prioritized and can lead to good clinical performance in the management of patients with suspected appendicitis, with no significant increase in rates of complicated appendicitis and negative findings on appendectomy.  相似文献   
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