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991.

Background

Biological monitoring of healthy workers exposed to hazardous dusts lack validated screening tools. Induced sputum (IS) cellular profile was compared with bronchoalveolar lavage fluid (BALF) profile in asbestos exposed workers in order to assess its usefulness in monitoring workers exposed to asbestos for a long period of time.

Methods

IS and BALF analysis was performed in 39 workers of a car brakes and clutches factory that uses chrysotile asbestos. Selection criteria were an employment history of > 15 years and the absence of a diagnosis of pneumonoconiosis. The type of cells, the existence of dust cells, of iron laden macrophages and of asbestos bodies were assessed and compared between IS and BALF samples.

Results

35 IS samples (90%) had dust cells, 34 (87%) iron laden macrophages and in 8 samples (21%) asbestos bodies were found. In most samples neutrophils were dominated. Samples with asbestos bodies (ABs) had significantly higher lymphocytes and lower neutrophils count compared with the samples without ABs. Macrophages and neutrophils in IS and BALF exhibited significant inter-relations (Spearman's rho: 0.26-0.29, p < 0.05) while IS lymphocytes count showed an inverse relation with BALF neutrophils (Spearman's rho: -0.36). Neutrophils and dust cells were highly correlated between the samples (Spearman's rho: 0.35, p < 0.05) while IS dust cells and lymphocytes were inversely related (Spearman's rho: -0.36, p < 0.05). More years of employment in the company was related with more neutrophils (Spearman's rho: 0.26) and less lymphocytes (Spearman's rho: -0.33) count. In multivariate analysis the presence of AB in IS samples was strongly related to the presence of asbestos bodies and lymphocytes count in BALF samples.

Conclusions

IS and BALF analysis showed a similar cellular profile indicating that IS sampling in exposed workers to asbestos as a less invasive and expensive method may be useful in providing an insight both for inhalation of dusts and inflammatory processes in the lung.  相似文献   
992.
993.
994.

Background  

We previously identified eight known and novel genes differentially expressed in the small intestines of wild type and W/W V mice, which have greatly reduced populations of the interstitial cells of Cajal, that are responsible for the generation of electrical slow waves, by using a differential gene display method.  相似文献   
995.
996.
Cutaneous melanoma represents the main cause of death among skin cancers. Early diagnosis gives, for the time being, the only possibility for high rate of curative treatment. Diagnosis is based on pathological findings, and at primary tumor stage, Breslow thickness of the lesion is the best prognostic index. At local stage of the disease, treatment is precisely codified by international recommendations and consensus conferences. Follow-up after surgical treatment is also well codified. Treatment of lymph node invasion or metastatic disease is, on the other hand, less codified. Despite recent advances, especially in immunotherapy, treatment of advanced stages of melanoma remains difficult.  相似文献   
997.
Until the early 1970s the traditional sleeping position for Dutch infants was not prone. After a much publicised lecture in October 1987 on the possible relation between sleeping prone and cot death, the fairly new habit of placing infants prone is being replaced by more traditional positions. The decrease in the prevalence of the prone sleeping position has been documented in six studies. Since 1987 the incidence of registered cot deaths has decreased from 1.04/1000 live births in 1986 to 0.44 in 1991; the real decrease of sudden unexpected death in infancy, however, is greater.  相似文献   
998.
In a longitudinal, population based study, overnight temperature recordings were made in the bedrooms of 152 babies aged 3-18 weeks and the insulation provided by their bedclothing was assessed. Outdoor temperatures for the study nights were also available. Parents applied more insulation on colder nights with lower bedroom temperatures than on warmer nights (mean 8.5 tog at 15 degrees C minimum bedroom temperature falling to 4.0 tog at 25 degrees C). For a particular temperature they also applied 2 tog more insulation in winter than in summer. The amounts of bedclothing used in the home were compared with insulation levels predicted to achieve thermo-neutrality over a similar range of environmental temperature from heat balance studies in young infants. They corresponded closely. The average amount of bedclothing chosen for babies in Avon allows them to remain in thermoneutral conditions throughout the night. These values are proposed as broad guidelines for the thermal care of young babies at night.  相似文献   
999.
The reported association of cot death and sleeping prone could be due to rebreathing of expired gases. A mechanical model simulating the respiratory system of an infant, exhaling warm humidified air with an end tidal carbon dioxide of 5%, has been used to investigate this. Some commonly used bedding materials caused an accumulation of carbon dioxide of 7% to over 10% with the model lying face down. This phenomenon persisted even with the head inclined at 45 degrees, but only on very soft materials, and could be a cause of cot death in a baby unresponsive to asphyxial blood gas changes. A coir fibre mattress allowed complete dispersal of exhalate as did a rubber sheet between any mattress and the covering sheet.  相似文献   
1000.
Recombinant interferon gamma has been used prophylactically in children with chronic granulomatous disease, but its role in the treatment of acute infective episodes has not been defined. A 3 year old boy presented with multiple candidal liver abscesses and was given intravenous antifungal treatment and he showed initial improvement. After six weeks his erythrocyte sedimentation rate and C reactive protein remained raised, and a computed tomogram showed a single abscess in the left lobe of the liver from which pus was drained and Staphylococcus aureus isolated. During the next eight months the abscess persisted despite appropriate intravenous antibiotics and percutaneous drainage. Subphrenic extension precluded definitive surgery. Nine months after initial presentation recombinant interferon gamma 0.05 mg/m2 intravenously was commenced three times a week. Complete resolution occurred within two months. It is concluded that interferon gamma is useful in treating infective episodes, and further study of the use of prophylactic antimicrobial treatment and intermittent interferon gamma during acute episodes is now required.  相似文献   
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