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Background  

Few studies have investigated the independent effects of occupational exposures and smoking on chronic bronchitis and airflow obstruction. We assessed the association between lifetime occupational exposures and airflow obstruction in a cross-sectional survey in an urban-industrial area of Catalonia, Spain.  相似文献   
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Hepatoblastoma (HB) is the most frequent pediatric primary liver tumor. When the tumoral lesions can be resected, prognosis is generally favorable. However, the...  相似文献   
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BACKGROUND: The renal reabsorption of natural nucleosides and a variety of nucleoside-derived drugs relies on the function of the apically located, Na(+)-dependent, concentrative nucleoside transporters CNT1, CNT2, and CNT3 (SLC28A1, SLC28A2, and SLC28A3). The aims of this study were to determine the segmental localization of the three SLC28 family members and to establish whether streptozotocin-induced diabetes alters their expression. METHODS: SLC28 expression was measured by real-time polymerase chain reaction (PCR) on microdissected sections of rat nephrons. Diabetes was induced by streptozotocin treatment and the biochemical profiles of control, diabetic, and insulin-treated rats were established. The effect of diabetes on SLC28 expression was assessed in those segments that significantly express SLC28 genes. RESULTS: CNT1-3 mRNAs were expressed in the proximal tubule and glomerulus. In addition, CNT2 and CNT3 mRNAs were expressed in the outer medullary and cortical collecting duct, respectively. Diabetes reduced expression of the three CNTs in almost all nephron segments, and this effect was not prevented by an insulin treatment that normalized all blood and urine parameters. Diabetes increased CNT1 and CNT3 expression in the glomerulus and insulin treatment decreased it. CONCLUSION: The relative distribution of SLC28 gene expression suggests a role for the proximal tubule in renal nucleoside clearance and an accessory role for CNT2 and CNT3, in adenosine-mediated regulation of collecting duct functions. Diabetes probably may impair nucleoside clearance independently of insulin.  相似文献   
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ObjectiveTo determine how many dispensary drugs should be in the safety stock in a tertiary hospital in accordance with the risk level and the number of days that the hospital is able to withstand a stockout.MethodsWe statistically analysed the infliximab order recorded over a period of 120 days. This drug is relevant for this study as it is costly and is immediately supplied to the clinic. Using the data records for purchasing and dispensing in our department, we created a table to compare the level of risk assumed with the number of units in stock and the number of days that the safety stock should last. In addition, we calculated how much stock there should be in accordance with different heuristic rules used by pharmacy departments.ResultsIn the period being studied, the daily order was 11.4 ± 14.8 units of infliximab. Using the methodology proposed, we discovered that there should be 79 units in the safety stock. Other hospital rules determine values of 47 and 119 units.ConclusionsThe method proposed allows us to discover the risk level that is assumed when selecting the safety stock. Therefore, we are able to design a safety stock policy consistent with the risk level adopted. Under certain assumptions the safety stock quota provided by this method could be reduced. Lastly, there is a notable difference between the safety stock values suggested by different rules, as it has been shown in this article.  相似文献   
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Aim of the review To study the prevalence of drug interactions in hospital healthcare by reviewing literature. Method A review was carried out of studies written in Spanish and English on the prevalence of drug interactions in hospital care published in Pubmed between January 1990 and September 2008. The search strategy combined free text and MeSH terms, using the following keywords: ??Drug interaction??, ??prevalence?? and ??hospital??. For each article, we classified independent variables (pathology, age of population, whether patients were hospitalized or not, geographical location, etc.) and dependent variables (number of interactions per 100 patients studied, prevalence of patients with interactions, most common drug interactions, and others). Results The search generated 436 articles. Finally, 47 articles were selected for the study, 3 provided results about drug interactions with real clinical consequences, 42 about potential interactions, and 2 described both. The prevalence of patients with interactions was between 15 and 45?% and the number of interactions per 100 patients was between 37 and 106, depending on the group of studies analyzed. There was a considerable increase in these rates in patients with heart diseases and elderly persons. Conclusion There is a large number of studies on the prevalence of drug interactions in hospitals but they report widely varying results. The prevalence is higher in patients with heart diseases and elderly people.  相似文献   
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For drugs such as anticancer agents every effort should be made to minimize inter-patient variability in drug exposure in order to maximize the benefit while maintaining an acceptable risk level of serious adverse effects. Anticancer drugs generally have a preferential route of elimination, either in urine or in bile and feces. In consequence, dose individualization to renal and liver function permits excessive toxicity to be avoided and expected therapeutic benefit to be achieved. However, less is known about the most appropriate starting doses of antineoplastic agents in these individuals. In this review, we discuss trials that have specifically assessed new targeted agents dosing strategies (mainly monoclonal antibodies and tyrosine kinase inhibitors) in the setting of overt biochemical renal and liver dysfunction and we proportionate recommendations and practical guidelines for dose individualization.  相似文献   
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