Study objectives: To examine whether or not the presence of mist or fog affects respiratory conditions in asthmatic children.Design: A retrospective study.Preparation and methods: There were 754 visits by children with asthma to the emergency room at night (between 18:00 p.m. and 9:00 a.m.) during a two-year period. Meteorological data were checked at a local fire station and regional meteorological observatory. We evaluated the relation between meteorological data and the number of emergency room visits of asthmatic children. Results: The mean number of asthmatic children who visited the emergency room was higher on misty or foggy nights than on clear nights (1.2±1.2 people/ night vs. 0.8±0.9 people/night, p<0.0001). Mist and fog had an increased odds ratio (OR) of emergency room visits of asthmatic children (1.74, p<0.001). In addition, increased OR was found for high atmospheric temperature (4.39, p<0.0001). Multivariate analysis showed mist and fog (p<0.0001), average atmospheric temperature (p<0.0001), and day-to-day change of temperature (p<0.05) were related to the number of asthmatic children (n=731, r=0.428, p<0.0001). Conclusions: Our results suggest that the presence of mist and fog causes the exacerbation of asthma in children. It is not clear which is related to the high frequency of emergency room visits of asthmatic children, airborne water droplets or the meteorological condition that causes mist or fog, but the prophylaxis for exacerbation may decrease the frequency of emergency room visits. 相似文献
Disability glare, affecting e.g. road safety at night, may result either from intraocular light scattering or from external conditions such as fog. Measurements were made of light scattering in fog and compared with intraocular straylight data for normal eyes and eyes with simulated cataract. All measurements were made with a direct compensation flicker method. To estimate light scattering levels in fog, straylight measurements were carried in a fog chamber for different densities of fog. Density was characterized by the meteorological term visibility V and ranged from 7 to 25. Test distance for measurements in the fog was constant at 5 m. Cataract eye conditions were simulated by placing a light scattering polymer dispersed liquid crystal (PDLC) filter with scatterers of submicron size in front of the normal eye. All measurements were made using each of three broad-band color stimuli – red, green and blue (produced either with LEDs or a color CRT monitor). Differences were found in both the level and the spectral characteristics of scattering under the different conditions. The measured values of the straylight parameter, s , in artificial fog showed no noticeable spectral dependence at any visibility range. Increasing the visibility range caused an exponential decrease in the straylight. Intraocular straylight measured with the clear eye showed an increase at the red and blue ends of the spectrum as compared to the green. Straylight measured using PDLC plates with different transparency levels showed a spectral dependence which decreased with wavelength. The scattering introduced by the PDLC plate therefore failed to give a valid simulation of cataract and fog conditions for polychromatic stimuli, due to its erroneous spectral dependence. 相似文献
This study examined the possibility of using biological monitoring to assess deltamethrin exposure among greenhouse workers.
The synthetic pyrethroid deltamethrin was sprayed in five greenhouses by cold fog generators, and the exposure was biologically
monitored by analysing the concentration of its metabolite, 3-phenoxybenzoic acid, by a gas chromatographic method after derivatization
with pentafluorobenzyl bromide. 3-Phenoxybenzoic acid was found in the urine of two of the ten workers studied. The urine
concentration of the metabolite varied from 2.4 to 51.7 μg/l. These results show that 3-phenoxybenzoic acid is suitable for
biological monitoring for the assessment of exposure to deltamethrin. 相似文献
Introduction: Patients with coeliac disease commonly report symptoms of ‘brain fog’. The aim of this study was to assess self-reported symptoms of impaired concentration in coeliac disease before and after treatment with gluten-free diet, compared with healthy controls and patient controls.
Methods: Patients with newly diagnosed coeliac disease were included consecutively from two out-patient clinics. The patients completed the questionnaires Adult ADHD Self-Report Scale v1.1 Symptoms Checklist (ASRS), Hospital Anxiety and Depression Scale (HADS) and Gastrointestinal Symptom Rating Scale (GSRS) prior to start of a gluten-free diet and after at least 12 months on the diet. Patients with an established diagnosis of inflammatory bowel disease served as patient controls (n?=?36). Health care personnel at Oslo University Hospital served as healthy controls (n?=?60) and filled out ASRS and HADS.
Results: A total of 31 newly diagnosed coeliac patients were included in the study. Of these, 26 patients met for follow-up and repeated the questionnaires. Prior to treatment, patients with coeliac disease had significantly higher scores than healthy controls on both the ASRS (p?=?.0014) and HADS (p=.0004). After a gluten-free diet, their scores improved and were not significantly different from healthy controls. There were no significant differences between patients with coeliac disease prior to treatment and patient controls with inflammatory bowel disease.
Conclusion: Prior to treatment, coeliac disease patients reported significantly more symptoms than healthy controls on ASRS and HADS. The differences disappeared after a minimum of 12 months on a gluten-free diet. 相似文献