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41.
Background:  Sample sizes in studies of childhood chronic fatigue remain small and there is a need to integrate research findings and establish common criteria.
Method:  This is a detailed report of 20 children with medically unexplained fatigue, referred to as Chronic Fatigue Syndrome (CFS). It includes an uncontrolled outcome study of treatment based on a pragmatic cognitive-behavioural model adapted for children at Great Ormond Street Hospital for Children.
Results:  The data revealed psychological distress at 30 times the prevalence found in the normal child population, with specific high-ranking symptoms, including headache, social withdrawal and decreased appetite. Onset tended to occur at 11 years of age with some earlier problems at school age, suggesting it might be possible to identify those most at risk. Follow-up demonstrated improvement in 87% of the sample (parental report), a significant increase in school attendance and a significant decrease in symptom severity. Factors associated with good outcome were short duration of fatigue (less than a year) and behaviours that tended to combat the cycle of avoidance, such as carefully planned home-tuition.
Conclusions:  Recording a comprehensive range of symptoms and factors facilitates comparisons within and between child studies. It is proposed that symptom severity is a particularly relevant measure for Chronic Fatigue Syndrome which is characterised by persisting symptoms.  相似文献   
42.
AIMS: To present an age-stratified approach to the diagnosis of obstructive lung disease based on asthma and COPD guidelines and epidemiology. METHODS: Asthma guidelines emphasize the role of the history and physical examination, with pulmonary function used primarily to confirm the diagnosis. COPD guidelines begin with symptoms and risk exposure, presenting spirometry as the primary diagnostic maneuver. Data from the National Health Interview Survey and the Third National Health and Nutrition Examination Survey illustrate relationships in prevalence of asthma and COPD in nationally representative samples. RESULTS: Asthma prevalence in adults declines with age from 5-10% at age 20-40 to 4-8% above age 60. COPD is uncommon in adults under age 40 but increases with age, surpassing asthma in older adults. CONCLUSIONS: These trends suggest that asthma screening is most useful in adults up to age 40, after which COPD screening and differential diagnosis are of comparable or greater utility.  相似文献   
43.
Necrotizing fasciitis (NF) is a potentially fatal infection of the skin and soft tissue. The early presentation may first appear as cellulitis. The skin stays intact in the early stages of NF; this leads to a deceptive benign appearance. The skin typically appears red, hot and exquisitely tender. Blisters may or may not be present. Severe local pain, which is out of proportion to the size and type of wound, is a hallmark sign seen in NF. Recognition of the signs and symptoms, as well as timely diagnosis and treatment of this condition is imperative. This is necessary in order to assist in preventing widespread tissue destruction, and enhance favorable patient outcomes. The purpose of this paper is to increase the knowledge and understanding of NF and to discuss the nurses' role in minimizing unfavorable outcomes.  相似文献   
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The 11C-labelled benzodiazepine antagonist Ro 15–1788 (flumazenil) and positron emission tomography (PET) were used to determine quantitative characteristics of benzodiazepine receptor binding in the neocortex of healthy young men. Saturating doses of unlabelled flumazenil administered i.v., before or together with the ligand-reduced 11C-flumazenil accumulation in the neocortex by about 90 per cent. Saturating doses of unlabelled flumazenil had little effect on the accumulation of radioactivity in the benzodiazepine receptor-poor regions such as pons or white matter. By giving graded doses of unlabelled flumazenil together with the tracer, saturation isotherms were obtained allowing the calculation of receptor density (Bmax) and equilibrium dissociation constant (Kd) values on the basis of certain assumptions Bmax values were in the order of 90 pmol/g and Kd values in the order of 10 nM in the neocortex. Scatchard and Hill plots of the radioactivity data indicated that 11C-flumazenil binds to saturable sites of a homogeneous population. The data indicate that intravenous doses of 1 or 2 mg flumazenil result in a benzodiazepine receptor occupancy of about 50 per cent. The method described should be useful for studying regional differences in benzodiazepine receptor characteristics in the living human brain in healthy subjects and neuropsychiatric disorders, and also in relation to treatment with drugs interacting with benzodiazepine receptors.  相似文献   
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The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc.  相似文献   
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Most patients who survive a stroke experience some degree of physical recovery. Selecting the appropriate outcome measure to assess physical recovery is a difficult task, given the heterogeneity of stroke etiology, symptoms, severity, and even recovery itself. Despite these complexities, a number of strategies can facilitate the selection of functional outcome measures in stroke clinical trial research and practice. Clinical relevance in stroke outcome measures can be optimized by incorporating a framework of health and disability, such as the International Classification of Functioning, Disability, and Health (ICF). The ICF provides the conceptual basis for measurement and policy formulations for disability and health assessment. All outcome measures selected should also have sound psychometric properties. The essential psychometric properties are reliability, validity, responsiveness, sensibility, and established minimal clinically important difference. It is also important to establish the purpose of the measurement (discriminative, predictive, or evaluative) and to determine whether the purpose of the study is to evaluate the efficacy or effectiveness of an intervention. In addition, when selecting outcome measures and time of assessment, the natural history of stroke and stroke severity must be regarded. Finally, methods for acquiring data must also be considered. We present a comprehensive overview of the issues in selecting stroke outcome measures and characterize existing measures relative to these issues.  相似文献   
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