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81.
《Inhalation toxicology》2013,25(6):500-521
This paper provides a review of the relevant literature on refractory ceramic fibers (RCFs), summarizing relevant data and information on the manufacture, processing, applications, potential occupational exposure, toxicology, epidemiology, risk analysis, and risk management. RCFs are amorphous fibers used for high-temperature insulation applications. RCFs are less durable/biopersistent than amphibole asbestos, but more durable/biopersistent than many other synthetic vitreous fibers (SVFs). Moreover, as produced/used, some RCFs are respirable. Toxicology studies with rodents using various exposure methods have shown that RCFs can cause fibrosis, lung cancer, and mesothelioma. Interpretation of these animal studies is difficult for various reasons (e.g., overload in chronic inhalation bioassays). Epidemiological studies of occupationally exposed cohorts in Europe and the United States have demonstrated measurable effects (e.g., mild respiratory symptoms and pleural plaques) but no disease (i.e., no interstitial fibrosis, no excess lung cancer, and no mesothelioma) to date. The RCF industry, working cooperatively with various government agencies in the United States, has developed a comprehensive product stewardship program (PSP) to identify and control risks associated with occupational exposure. One provision of the PSP is the adoption of a voluntary recommended exposure guideline (REG) of 0.5 fibers/milliliter (f/ml). Selected on the basis of prudence and demonstrated feasibility, compliance with the REG should reduce risks to levels between 0.073/1000 and 1.2/1000, based on extrapolations from chronic animal inhalation studies.  相似文献   
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Malignant mesothelioma is a rare malignancy with a poor prognosis whose development is related to asbestos fiber exposure. An increasing role of genetic predisposition has been recognized recently. Pleural biopsy is the gold standard for diagnosis, in which the identification of pleural invasion by atypical mesothelial cell is a major criterion. Pleural effusion is usually the first sign of disease; therefore, a cytological specimen is often the initial or the only specimen available for diagnosis. Given that reactive mesothelial cells may show marked atypia, the diagnosis of mesothelioma on cytomorphology alone is challenging. Accordingly, cell block preparation is encouraged, as it permits immunohistochemical staining. Traditional markers of mesothelioma such as glucose transporter 1 (GLUT1) and insulin-like growth factor 2 mRNA-binding protein 3 (IMP3) are informative, but difficult to interpret when reactive proliferations aberrantly stain positive. BRCA1-associated protein 1 (BAP1) nuclear staining loss is highly specific for mesothelioma, but sensitivity is low in sarcomatoid tumors. Cyclin-dependent kinase inhibitor 2A (CDKN2A)/p16 homozygous deletion, assessed by fluorescence in situ hybridization, is more specific for mesothelioma with better sensitivity, even in the sarcomatoid variant. The surrogate marker methylthioadenosine phosphorylase (MTAP) has been found to demonstrate excellent diagnostic correlation with p16. The purpose of this review is to provide an essential appraisal of the literature regarding the diagnostic value of many of these emerging biomarkers for malignant mesothelioma in effusion cytology.  相似文献   
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IntroductionHigher target conformity and better sparing of organs at risk with modern radiotherapy (RT) may result in higher tumor control and less toxicity. In this study, we compare our institutional multimodality therapy experience of adjuvant chemotherapy and hemithoracic intensity-modulated pleural RT (IMPRINT) with previously used adjuvant conventional RT (CONV) in patients with malignant pleural mesothelioma (MPM) treated with lung-sparing pleurectomy/decortication (P/D).MethodsWe analyzed 209 patients who underwent P/D and adjuvant RT (131 who received CONV and 78 who received IMPRINT) for MPM between 1974 and 2015. The primary end point was overall survival (OS). The Kaplan-Meier method and Cox proportional hazards model were used to calculate OS; competing risks analysis was performed for local failure-free survival and progression-free survival. Univariate analysis and multivariate analysis were performed with relevant clinical and treatment factors.ResultsThe median age was 64 years, and 80% of the patients were male. Patients receiving IMPRINT had significantly higher rates of the epithelial histological type, advanced pathological stage, and chemotherapy treatment. OS was significantly higher after IMPRINT (median 20.2 versus 12.3 months, p = 0.001). Higher Karnofsky performance score, epithelioid histological type, macroscopically complete resection, and use of chemotherapy/IMPRINT were found to be significant factors for longer OS in multivariate analysis. No significant predictive factors were identified for local failure or progression. Grade 2 or higher esophagitis developed in fewer patients after IMPRINT than after CONV (23% versus 47%).ConclusionsTrimodality therapy including adjuvant hemithoracic IMPRINT, chemotherapy, and P/D is associated with promising OS rates and decreased toxicity in patients with MPM. Dose constraints should be applied vigilantly to minimize serious adverse events.  相似文献   
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<正>1病历资料男性患者,25岁,以"腹胀1个月,发热半个月,加重2 d"为主诉,于2011年10月14日至本科住院治疗。患者10余年前体检发现HBsAg阳性,自述当时肝功能正常,未予重视及系统诊治。1个月前自觉腹胀,体检发现"少量腹水",仍未重视及进一步诊治,近半个月出现发热,最高体温38.7℃,无恶寒,无鼻塞流涕,无咳嗽咳痰,在当地诊所予对症治疗后体温下降,未行进一步诊治。2 d前自觉腹胀加重,遂至本院肝病门诊就  相似文献   
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Community-acquired pneumonia (CAP) is a prevalent disease among children and is frequently associated with both diagnostic and therapeutic uncertainties. Consensus has been reached between SEPAR, SENP and SEIP, and their conclusions are as follows:Etiology depends mainly on age and other factors and no single analytical marker offers absolute diagnostic reliability.In the event of clinical suspicion of pneumonia in a healthy child, chest X-ray is not necessary. Chest ultrasound is increasingly implemented as a follow-up method, and even as a diagnostic method.The empirical antibiotic treatment of choice In typical forms of the disease is oral amoxicillin at a dose of 80 mg/kg/day for 7 days, while in atypical presentations in children older than 5 years, macrolides should be selected. In severe typical forms, the combination of 3rd generation cephalosporins and cloxacillin (or clindamycin or vancomycin) administered intravenously is recommended.If pleural drainage is required, ultrasound-guided insertion of a small catheter is recommended. Intrapleural administration of fibrinolytics (urokinase) reduces hospital stay compared to simple pleural drainage.In parapneumonic pleural effusion (PPE), antibiotic treatment combined with pleural drainage and fibrinolytics is associated with a similar hospital stay and complication rate as antibiotic treatment plus video-assisted thoracoscopy (VATS).Systematic pneumococcal conjugate vaccination is recommended in children under 5 years of age, as it reduces the incidence of CAP and hospitalization for this disease.  相似文献   
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