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991.
The vast majority of birth parents and foster parents for children with special needs do the best they can in challenging circumstances. Many describe the frustrating circumstance of knowing more than their physicians about their child's unusual medical conditions. In general, physicians are well-advised to listen carefully to the reports of observant, caring parents and foster parents, and to give these observations at least as much weight as their own. However, in the work of our traveling clinic we have observed a number of situations of abuse and neglect which were perpetrated by parents or foster parents, and where the actual acts of abuse and/or neglect were wholly or in part endorsed, in writing, by the treating physician.  相似文献   
992.
The relationship between anthracosis, which is the deposition of black dust matter in the lung parenchyma, and the development of pulmonary adenocarcinoma has not been fully characterized. In order to clarify whether background black dust matter deposition could be implicated in the development of pulmonary adenocarcinoma, we measured the level of anthracosis at autopsy in 47 patients who had died of pulmonary adenocarcinoma. Both lungs of all 47 cadavers were examined. Twenty-micrometer sections were cut from formalin-fixed, paraffin-embedded blocks of the largest cut surface of each lung. Black dust matter was extracted from the sections and blotted onto a nitrocellulose membrane. The density of the blotted black dust matter was then analyzed using an imaging densitometer. There were no significant differences in the density of black dust matter deposition between lungs affected by pulmonary adenocarcinoma and control lungs. However, well differentiated adenocarcinomas tended to develop more frequently than poorly differentiated ones in lungs showing less deposition. We found a very strong correlation between the degree of black dust matter deposition and smoking history. Patients with severe anthracosis tended to have a poorer prognosis than those with mild anthracosis.  相似文献   
993.
994.
BACKGROUND: Healthy volunteers exposed for 3 hr during weighing of pigs develop an airway inflammation characterized by a massive influx of neutrophilic granulocytes in the upper and lower airways and increased bronchial responsiveness to methacholine. The purpose of the present study was to investigate health effects from exposure during cleaning of the swine confinement building and to evaluate the effect of a respiratory protection device. METHODS: Sixteen subjects were exposed for 3 hr during cleaning of a swine confinement room with a high-pressure cleaner. Seven out of sixteen subjects were equipped with a mask during exposure. RESULTS: The bronchial responsiveness increased in all subjects following exposure, significantly more in the group exposed without a mask (P < 0.05). The cell concentration (mainly neutrophilic granulocytes) in nasal lavage fluid as well as the concentration of interleukin-8, increased significantly only in those subjects exposed without a respiratory protection device. In peripheral blood, an increase of neutrophilic granulocytes was observed in both groups, although it was significantly higher in the group without mask (P < 0.05). The inhalable dust level was 0.94 (0.74 - 1.55) mg/m(3) and respirable dust 0.56 (0.51-0.63) mg/m(3). CONCLUSION: Exposure to dust aerosols during the cleaning of the interior of a swine confinement building induces increased bronchial responsiveness and an acute inflammatory reaction in the upper airways. The use of a mask attenuated but did not abolish the inflammatory response. This suggests that gases and/or ultrafine particles in this environment could be important factors in the development of increased bronchial responsiveness.  相似文献   
995.
Several studies have demonstrated that early intervention may modulate the natural course of atopic disease. Our objective was to prevent sensitization to house-dust mite and food allergens, as well as the development of atopic symptoms during infancy, by the combination of an educational package and the use of mite allergen-impermeable mattress encasings. A multicentre European, population-based, randomized, controlled study of children at increased atopic risk [Study on the Prevention of Allergy in Children in Europe (SPACE)] was performed in five countries (Austria, Germany, Greece, the UK, and Lithuania), and included three cohorts – schoolchildren, toddlers, and newborns. We report on the newborn cohort. A total of 696 newborns were included from Austria, the UK, and Germany. Inclusion criteria were: a positive history of parental allergy; and a positive skin-prick test or specific immunoglobulin E (IgE) (IgE ≥ 1.43 kU/L) against at least one out of a panel of common aeroallergens in one or both parents. At 1 year of age, the overall sensitization rate against the tested allergens [dust-mite allergens: Dermatophagoides pteronyssinus and Dermatophagoides farinae ( Der  p and Der  f)] and food allergens (egg, milk) in the prophylactic group was 6.21% vs. 10.67% in the control group. The prevalence of sensitization against Der  p was 1.86% in the prophylactic group vs. 5% in the control group. In conclusion, we were able to demonstrate, in a group of newborns at risk for atopic diseases, that the sensitization rate to a panel of aero- and food allergens could be effectively decreased through the use of impermeable mattress encasings and the implementation of easy-to-perform preventive measures.  相似文献   
996.
用双核微量核法对三种煤尘亚硝化前后的致突变性进行检测,结果未经亚硝化时,三种煤尘均呈现致突变作用;而在酸性条件下被亚硝化后,二种烟煤表现出了致突变性能。试验提示,在检测煤尘致突变作用中,体外细胞双核微核法的灵敏度高于传统微核法。  相似文献   
997.
Endotoxin exposure and symptoms in asthmatic children   总被引:6,自引:0,他引:6  
Endotoxins (ET) are pro-innammatory substances present in hou.sc dust which may increase non-specific bronchial reactivity in asthmatic patients. Endotoxins (EU/g) and Der p I levels were compared in the homes often asthmatic and ten control children, aged 6-16 years, living in Sao Paulo, Brazil. The houses were visited once a month from February 1993 lo February 1994 and dust samples were collected from the bedding and floor of each subject's house. No significant differences were observed in ET and Derp 1 levels in the homes of asthmatics and controls. The highest ET levels were detected in January and November, whereas the lowest levels were detected in April and August (p < 0.05). demonstrating a distinct seasonal distribution. The highest Der p I levels in bedding were observed in July and the lowest in February (p < 0.05). while Derp I levels in floor did not show significant differences throughout the year. Symptom and medication scores were evaluated monthly in the group of asthmatic children. There was a significant correlation (p < 0.05. r = 0.63) between clinical symptom scores and ET exposure, however no significant correlation was found for mite exposure (p > 0.05. r = 0.19). The results suggest that ET exposure exacerbates asthmatic symptoms in mite allergic, asthmatic children.  相似文献   
998.
Several studies, in particular in adult groups, have evaluated the involvement of mites in the pathogenesis of atopic dermatitis (AD). This still remains controversial. The objective of this study was to determine the level of house dust mites (HDMs) in the beds of a group of children with AD and correlate these levels with their allergometric assessment. Forty-one children with AD underwent allergometric tests (prick test, patch test and radioallergosorbent test, RAST) and the concentration levels of HDMs in their homes were evaluated. Our data show that about half of the children (51%) with AD presented Dermatophagoides pteronyssinus positivity (prick test and/or RAST and/or patch test). Dust was collected in the period October-November from the children's beds, by the same two operators, using a dust-collection device. The dust mite level was tested by an enzyme-linked immunosorbent assay with antibody against Der p 1 allergen. Ten children (24%) presented a Der p 1 concentration > 2 microgram/g of dust (the value assumed to be a risk level for sensitization), 20 (49%) between 0.1 and 2 microgram/g and 11 (27%) < 0.1 microgram/g of dust. In the group with the highest Der p 1 concentration (> 2 microgram/g dust) nine children (90%) presented an allergometric D. pteronyssinus sensitivity, the difference with the other two groups being statistically significant at P < 0.018. The results of the present study show that the highest HDM concentrations were observed in the group with an allergometric D. pteronyssinus positivity (prick test and/or RAST and/or patch test). It is hypothesized that a higher HDM concentration may elicit D. pteronyssinus IgE sensitization and delayed hypersensitivity in children with AD.  相似文献   
999.
1000.
Summary The ventilatory function of 48 workers occupied on the average for six years in a plant producing diamond-cobalt circular saws was compared with that of 23 control subjects. The geometric mean airborne cobalt concentrations in the two main work areas amounted to 15.2 and 135.5 g/m3 respectively. The spirometric changes found in the exposed workers were compatible with a moderate restrictive syndrome and were correlated with duration of exposure.  相似文献   
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