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The aim of this multicenter, double-masked study was to compare the efficacy and safety of two different doses of inhaled fluticasone propionate dry powder--50 micrograms and 100 micrograms--administered BID via a multidose powder inhaler with those of placebo in the treatment of children with persistent asthma. After a 2-week run-in period, 263 patients were randomized to treatment with twice-daily placebo (n = 92), fluticasone 50 micrograms (n = 85), or fluticasone 100 micrograms (n = 86) for 12 weeks. One hundred sixty-six (63%) patients were male, and 224 (85%) were white, with a mean age of 8 years. Two hundred twenty-one (84%) patients were atopic, and 167 (63%) had been asthmatic for 1 to 5 years. Baseline mean morning peak expiratory flow (PEF) values were 207 L/min, 199 L/min, and 194 L/min, and baseline percentages of predicted normal values were 86%, 80%, and 81% for the groups receiving placebo, fluticasone 50 micrograms, and fluticasone 100 micrograms, respectively. At the end of the first week of treatment, patients in both fluticasone groups had significantly greater improvements in morning PEF than did those receiving placebo. Patients experienced mean increases of 4 L/min, 22 L/min, and 26 L/min with placebo, fluticasone 50 micrograms, and fluticasone 100 micrograms, respectively. At the end point (the last evaluable visit), patients in both fluticasone groups continued to have significantly greater improvements in morning PEF than did patients receiving placebo. Patients experienced mean increases of 17 L/min, 50 L/min, and 57 L/min with placebo, fluticasone 50 micrograms, and fluticasone 100 micrograms, respectively. Changes in the percentage of predicted values by end point were 8%, 20%, and 26% with placebo, fluticasone 50 micrograms, and fluticasone 100 micrograms, respectively. The probability of remaining in the study, according to predefined withdrawal criteria, indicated a significant treatment difference in favor of fluticasone. Withdrawal criteria were met by 63%, 42%, and 29% of patients receiving placebo, fluticasone 50 micrograms, and fluticasone 100 micrograms, respectively. This study clearly demonstrates the superiority of fluticasone 50 and 100 micrograms BID over placebo in the treatment of persistent asthma in children.  相似文献   
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BACKGROUND: Mental disorders impose a multi-billion dollar burden on the economy each year; translating the burden into economic terms is important to facilitate formulating policies about the use of resources. METHODS: For direct costs, data were obtained from national household interview and provider surveys; for morbidity costs, a timing model was used that measures the lifetime effect on current income of individuals with mental disorders, taking into account the timing of onset and the duration of these disorders, based on regression analysis of Epidemiologic Catchment Area study data. RESULTS: The total economic costs of mental disorders amounted to US$147.8 billion in 1990. Anxiety disorders are the most costly, amounting to $46.6 billion, or 31.5% of the total; schizophrenic disorders accounted for $32.5 billion, affective disorders for $30.4 billion, and other mental disorders for $38.4 billion. CONCLUSIONS: Mental illnesses, especially anxiety disorders, are costly to society. Although anxiety disorders have a higher prevalence than affective disorders and schizophrenia, use of medical care services is lowest for anxiety disorders. Anxiety disorders appear to be under-recognised and untreated even though treatment interventions have been shown to be effective and can be delivered in a cost-efficient manner.  相似文献   
134.
Selenomethionine, an amino acid occurring in proteins in place of methionine, reacts efficiently with oxidants, e.g., peroxynitrite, a biological oxidant generated in inflammatory states, to produce the oxidation product, methionine selenoxide. The present work describes the rapid and efficient reduction of the selenoxide to selenomethionine by glutathione in a stoichiometric reaction utilizing two equivalents of thiol. This nonenzymatic reaction establishes a defense line against peroxynitrite or other oxidants by selenomethionine residues in proteins, maintained by the ubiquitous thiol, glutathione.  相似文献   
135.
Seven patients conducted assessments in an outpatient clinic using a prescribed hierarchy of antecedent and consequence treatment components for their children's problem behavior. Brief assessment of potential treatment components was conducted to identify variables that controlled the children's appropriate behavior. Experimental control via a brief reversal was achieved for 6 of the 7 children, (1 child continued to behave appropriately following initial improvement in behavior). For these 6 children, improved behavior occurred with changes in treatment components. Our results extend previous studies of direct assessment procedures conducted in outpatient clinic settings.  相似文献   
136.
The selectins are a three-member family of leukocyte, platelet, and endothelial cell adhesion proteins that mediate leukocyte traffic into normal and inflamed tissues. P-selectin is expressed by endothelial cells and platelets, E-selectin by endothelial cells, and L-selectin by circulating leukocytes. To determine if selectin-mediated leukocyte adhesion influences the development of lung reperfusion injury, we studied hemodynamics and respiratory and inert gas exchange in sheep subjected to 3-hour in situ left lung ischemia followed by 6-hour left lung reperfusion with the right lung excluded. Ten minutes before reperfusion, eight animals received EL-246 (1 mg/kg intravenously), a novel antihuman selectin antibody that recognizes and blocks both L- and E-selectin and cross-reacts in sheep. Eight control animals with ischemia received no treatment, whereas three received an isotype-matched antihuman L-selectin antibody that does not cross-react in sheep (DREG-56, 1 mg/kg intravenously). Eight sham control sheep underwent an identical operative procedure but were never subjected to ischemia. Volume-cycled, pressure-limited (20 cm H2O) mechanical ventilation was consistent in all animals throughout the experiment. Six-hour survival in EL-246 recipients (100%) was significantly higher than in either ischemic control sheep (37.5%) or DREG-56 recipients (33.3%), but gravimetric lung water was equivalent in EL-246 recipients (5.9 +/- 1.7 ml/kg), ischemic control sheep (8.3 +/- 3.0 ml/kg), and DREG-56 recipients (9.1 +/- 2.6 ml/kg).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The efficacy and safety of oral sildenafil, a potent inhibitor of phosphodiesterase type 5, were evaluated in men with diabetes mellitus and erectile dysfunction (ED). Twenty-one men (aged 42-65 years) were enrolled in a double-blind, placebo-controlled, three-way crossover study conducted in two parts. In part I, the effect of a single dose (25 mg or 50 mg) of sildenafil or placebo on penile rigidity was assessed by penile plethysmography during visual sexual stimulation. In part II, daily diary records of erectile activity and a global efficacy question were used to evaluate once-daily dosing with 25 mg or 50 mg of sildenafil or placebo for 10 days. After a single 50 mg dose of sildenafil, the adjusted geometric mean duration (min) of penile rigidity >60% at the base of the penis during visual sexual stimulation was significantly increased (10.1 min) compared with placebo (2.8 min; p = 0.0053). In part II, sildenafil significantly increased the number of erections considered sufficiently hard for vaginal penetration compared with placebo (p = 0.0005). Improved erections were reported by 50% and 52% of patients treated with 25 mg and 50 mg of sildenafil, respectively, compared with 10% of those receiving placebo (p values < 0.05). Adverse events were mostly mild or moderate in nature and included muscular pains, headache, and dyspepsia. Sildenafil is a well-tolerated and potentially efficacious oral treatment for ED in men with diabetes mellitus.  相似文献   
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140.
An Onchocerca volvulus expression library was differentially screened to identify a molecular marker distinguishing sowda (lichenified onchodermatitis) from other onchocerciasis forms. One clone, PG3, was recognized by pooled sera from patients with sowda, but not by pooled sera from patients with generalized onchocerciasis; it was not recognized by sera from patients with lymphatic filariasis or other helminth infections. The DNA of PG3 hybridized strongly with O. volvulus Eco RI-digested DNA, but not with DNA from Brugia spp., Trichinella spp., and humans. A weak reaction was observed with DNA from O. gibsoni and Acanthocheilonema viteae. The PG3 DNA sequence showed a high homology with both human and nematode collagens. Confirmation of the collagen-like nature of the sowda-specific PG3 product was obtained by amino terminal sequencing of the PG3 expression product, as well as by demonstrating its susceptibility to collagenase digestion. The characteristic recognition of the O. volvulus collagen specified by clone PG3 was confirmed by measuring antibody levels to the expressed product in individual sowda and generalized onchocerciasis sera, respectively. Identification of a nematode collagen antigen mainly recognized in sowda patients raises the possibility that this extreme form of dermatitis might arise through cross-reactivity between anti-O. volvulus collagen antibodies and human collagen. However, a relationship between the PG3 recognition by antibodies and the sowda pathogenesis could not be demonstrated.  相似文献   
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