Search results for "Concentration Response"
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Differences in sensitivity, maximal response and position of the concentration-response curve to methacholine between asthmatics, patients with aller…
1998
The aim of this study was to detect differences in maximal response and position of the concentration-response curves to methacholine between asthmatics and subjects with allergic rhinitis. A total of 228 adults (107 mild asthmatics, 96 allergic rhinitics and 25 healthy control subjects) were challenged with methacholine. The test was interrupted when FEV1 dropped by more than 40% or when the highest concentration of methacholine (200 mg ml-1) had been administered. Concentration-response curves were characterized by their PC20 (concentration of methacholine that produced 20% fall in FEV1 = airway sensitivity), and if possible, by their EC50 (concentration of methacholine that produced 50% …
Relationship between airway sensitivity to adenosine 5' monophosphate and the shape of the concentration-response curve to methacholine in subjects w…
2001
Abstract The objective of this study was to determine differences in airway sensitivity to adenosine 5′-monophosphate (AMP) between allergic rhinitis subjects with plateau and those without evidence of plateau on the concentration–response curves to methacholine. A total of 51 adults (38 subjects with allergic rhinitis and 13 healthy controls) were challenged with increasing concentrations of methacholine and AMP. The methacholine challenge was terminated when there was a 40% or more decrease in forced expiratory volume in 1 sec (FEV 1 ), whereas the AMP challenge was stopped when FEV 1 had fallen by more than 20%. A plateau for methacholine was detected in all 13 healthy controls and in 27…