BACKGROUND Peak expiratory flow rates (PEF) are often used to confirm the diagnosis of occupational asthma. The records are usually analysed qualitatively, and this may lead to interobserver disagreement. In this study the diagnostic value of a qualitative assessment of change in PEF was compared with objective measures of change in PEF and the results of a specific inhalation challenge test wi...

Gastro-oesophageal (GO) reflux is believed to be a possible cause of nocturnal asthma. The aim of this study was to see if there is any correlation between the incidence of GO-reflux at night and nocturnal asthma. Thirty-seven adult patients with a history of nocturnal asthma for more than one hundred days a year and of reflux disease were evaluated using 24 h pH-monitoring of the oesophagus an...

Airborne particles are associated with adverse health effects and contribute to excess mortality in epidemiological studies. A recent hypothesis proposes that the high numbers of ultrafine (<0.1 microm diameter) particles in ambient air might provoke alveolar inflammation and subsequently cause exacerbations in pre-existing cardiopulmonary diseases. To test the hypothesis adult asthmatics were ...

This study investigates the effects of pulsed electric fields (PEF) and freeze thawing (FT) pretreatments on juice yield quality from chicory by pressing (P). The four different modes (P, PEF-P, FT-P P-PEF-P) were compared. mode, PEF conditions, cossettes size yield, total soluble matter (°Bx), conductivity, pH, turbidity in expressed juices evaluated. kinetics for also investigated. For studie...

BACKGROUND The Oasys programme plots serial peak expiratory flow (PEF) measurements and produces scores of the likelihood that the recordings demonstrate occupational asthma. We have previously shown that the area between the mean workday and rest day PEF curves [the area between the curves (ABC) score] has a sensitivity of 69% and specificity of 100% when plotted from waking time using a cut-o...

BACKGROUND Serial peak expiratory flow (PEF) records have been recommended as a first-line investigation in workers suspected as having occupational asthma (OA). AIMS To determine which PEF variability index best differentiates workers with OA from non-occupational asthmatics and unaffected irritant-exposed workers. METHODS PEF was measured at least four times daily for at least 3 weeks in ...

v Zuskin, E., and Vali, F. (1971). Brit. J. industr. Med., 28, 159-163. Peak flow rate in relation to forced expiratory volume in hemp workers. Measurements of the forced expiratory volume in one second (FEV1.0) and the peak expiratory flow rate (PEF) were made in 99 non-smoking female hemp workers before and after the shift. A significant mean reduction of both FEV1.o and PEF (P < 0-01) over t...

Salmonella typhimurium cells were subjected to pulsed electric field (PEF) treatment at 25 kV/cm for 0-4 ms to investigate the effect of PEF on the cytoplasmic membrane lipids and oxidative injury of cells. Results indicated that PEF treatment induced a decrease of membrane fluidity of Salmonella typhimurium (S. typhimuriumi), possibly due to the alterations of fatty acid biosynthesis-associate...

Little is known about the response of variable orifice peak flow meters to high frequency flow input. The purpose of this study was to define and test dynamic requirements for such peak flow meters. In a population sample we measured peak expiratory flow (PEF), rise time (tr), from 10-90% PEF and the duration of the flow in excess of 97.5, 95 and 90% of PEF, by use of a carefully calibrated Fle...