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排序方式: 共有2293条查询结果,搜索用时 15 毫秒
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B.J. Lipworth R. A. Clark D. G. McDevitt 《Journal of clinical pharmacy and therapeutics》1991,16(3):187-191
The purpose of the present study was to evaluate the responsiveness of normal human airways to beta-adrenoceptor stimulation using a forced oscillation technique. Seven normal volunteers (aged 25 +/- 2 year) were studied on three occasions, separated by weekly intervals, using a single-blind randomized design. On day 1, subjects were given cumulative doses of inhaled salbutamol (100, 200, 500, 1000 micrograms); and identical placebo was given on the other two visits. Respiratory oscillation impedance (Ros) was measured at baseline and 15 min after each dose increment. The coefficients of variation (CV) for short-term intra-individual variability on each placebo day were 7.5 and 9.5, and 9.6% for long-term variability (measured over all three visits). The 95% confidence values (2SD) for the change in Ros required to exclude natural variability were 0.39, 0.50 and 0.53 cmH2O l-1 s, respectively. There was a small fall in Ros in response to salbutamol although the mean maximum change (0.46 cmH2O l-1 s) was not significant (by ANOVA). Thus, the change in Ros (sensitivity) was no greater than the 95% confidence value for natural variability (reproducibility). Regression analysis also showed no evidence of a dose-response relationship for Ros. 相似文献
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Catherine Jackson Brian Lipworth 《Annals of allergy, asthma & immunology》2003,90(6):674; author reply 674-674; author reply 675
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A. M. Wilson K. Haggart E. J. Sims B. J. Lipworth 《Clinical and experimental allergy》2002,32(10):1504-1509
BACKGROUND: In vitro studies have shown much higher H1-receptor antagonist potency with desloratadine (DL) compared to fexofenadine (FEX), although it is unclear whether this has any clinical relevance on disease control parameters in seasonal allergic rhinitis (SAR), especially for nasal congestion. OBJECTIVE: To compare the relative efficacy between presently recommended doses of DL and FEX on daily measurements of peak nasal inspiratory flow (PNIF) and nasal symptoms in SAR. METHODS: Forty-nine patients with SAR were randomized into a double-blind, placebo-controlled cross-over study during the grass pollen season, comparing 2 weeks of once daily treatment with (a) 180 mg FEX or (b) 5 mg DL, taken in the morning. There was a 7-10 day placebo run-in and washout prior to each randomized treatment. Measurements were made in the morning (AM) and in the evening (PM) for PNIF (the primary outcome variable), nasal and eye symptoms. The average of AM/PM values were used for analysis. RESULTS: There were significant (P < 0.05) improvements, compared to placebo, with FEX and DL, for PNIF, nasal blockage, nasal irritation, and total nasal symptoms, but not nasal discharge or eye symptoms. There were no significant differences between active treatments. Values for PNIF (L/min) for mean placebo baseline, mean difference from baseline (95% CI for difference) were 126, 10 (4-16) for FEX; and 122, 11 (4-17) for DL. The mean difference (95% CI) between FEX vs. DL was 1 L/min (-7-8). Values for total nasal symptoms (out of 12) were: 3.2, 0.7 (0.2-1.2) for FEX; and 3.4, 0.9 (0.3-1.5) for DL, and for nasal blockage (out of 3) were: 1.1, 0.2 (0.1-0.4) for FEX; and 1.2, 0.3 (0.1-0.5) for DL. The mean difference (95% CI) in total nasal symptoms and nasal blockage between FEX vs. DL was 0.1 (-0.6-0.8) and 0.1 (-0.2-0.3), respectively. CONCLUSIONS: Recommended once daily doses of fexofenadine and desloratadine were equally effective in improving nasal peak flow and nasal symptoms in SAR. 相似文献
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Stephanie Stouder Loren Jones Scott Brietzke Eric A Mair 《Otolaryngology--head and neck surgery》2007,136(5):827-831
OBJECTIVES: Oral appliances are designed to treat snoring and sleep apnea by advancing the mandible and tongue. We test the hypothesis that an oral appliance affects palatal snoring as well as tongue base obstruction. METHODS: Prospective observational cohort study. Sixty patients with a chief complaint of snoring with or without apnea were enrolled. Each patient underwent a home sleep test followed by 3 weeks sleeping with an oral appliance. Each patient then underwent a repeat home sleep test while using the device. RESULTS: There was a statistically significant improvement in the snores per hour (P = 0.0005), the maximum snoring loudness (P = 0.0001), average snoring loudness (P = 0.00001), and the percentage of palatal snoring (P = 0.0007). There was also a significant decrease in oxygen desaturation events (P = 0.003). CONCLUSIONS: This study suggests oral appliances may be effective treatment for both palatal and tongue base snoring. 相似文献
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Leanne Tamm Jeffery N. Epstein Richard E.A. Loren Stephen P. Becker Sarah B. Brenner Morgan E. Bamberger 《Journal of clinical child and adolescent psychology》2019,48(2):S131-S145
This goal of this study was to assess the initial feasibility and efficacy of a play-based intervention targeting executive functions (EF) and parent–child relationships in preschoolers compared with an active control group. Preschoolers with EF deficits (M age = 3.7 ± 0.47, predominantly White boys) and their parents were randomized to intervention (n = 36) or active control (n = 32) conditions. Child performance on EF tasks, parent and masked teacher ratings of EF and behavior, and masked clinician ratings of severity were collected at baseline and at 3 and 6 months postbaseline. Partial eta-squared effect sizes at .02 or higher comparing performance across the two groups was considered evidence of meaningful, albeit small, intervention effects. Intervention effects were observed for parent ratings of inattention, hyperactivity/impulsivity, and number/severity of problems experienced in various home situations, teacher ratings of severity of problems in various school situations, parent and teacher ratings of overall impairment, and clinician ratings of impairment. Intervention effects for functional improvements were maintained at the 6-month follow-up. No effect of the intervention was observed on the objective EF measures, although parent ratings of emotional control were improved for children in the intervention group. An intervention utilizing play-based activities targeting EF, when administered in a structured way by parents, is a promising approach for improving behavior in preschoolers with self-regulation deficits. More work is needed to investigate potential impact on EF and to disentangle mechanisms of action. It may be that the intervention’s focus on the structure and quality of parent–child interactions is a mediator of outcomes, rather than improved EFs. 相似文献
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Differential expression of CD22 (Lyb8) on murine B cells 总被引:2,自引:0,他引:2
Erickson Loren D.; Tygrett Lorraine T.; Bhatia Sudershan K.; Grabstein Kenneth H.; Waldschmidt Thomas J. 《International immunology》1996,8(7):1121-1129
Previous studies have established the distribution, biochemistryand functional attributes of human CD22, a B cell-restrictedglycoprotein. Recently, molecular cloning of the murine CD22equivalent revealed this molecule to be the same as the previouslydescribed Lyb8 alloantigen. Using the anti-Lyb8 mAb Cy34.1.2,the present report documents the expression patterns of CD22within the murine B cell compartment. The results demonstratethat in the bone marrow, murine CD22 is absent on the surfaceof pro-B cells, pre-B cells and newly emerging lgM+ B cells.CD22 is present at a low density on immature IgMhi B cells andfully expressed on mature recirculating B cells. In the periphery,murine CD22 is expressed at mature levels on all B cell subsetsincluding follicular, marginal zone, B1 and switched B cells.Further studies showed CD22 to be retained on activated murineB cells for extended periods. Finally, in combination with CD23and heat stable antigen, CD22 can be used to delineate the immaturesplenic B cells, and distinguish them from follicular and marginalzone cells. Together, the results demonstrate murine CD22 tobe a useful pan marker for all mature B cell subsets. 相似文献