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Objectives To identify independent predictors of outcome in patients with adenoid cystic carcinoma (ACC) of the paranasal sinuses and skull base.Design Meta-analysis of the literature and data from the International ACC Study Group.Setting University-affiliated medical center.Participants The study group consisted of 520 patients, 99 of them from the international cohort. The median follow-up period was 60 months (range, 32 to 100 months).Main Outcome Measures Overall survival (OS) and disease-specific survival (DSS).Results The 5-year OS and DSS of the entire cohort were 62% and 67%, respectively. The local recurrence rate was 36.6%, and the regional recurrence rate was 7%. Distant metastasis, most commonly present in the lung, was recorded in 106 patients (29.1%). In the international cohort, positive margins and ACC of the sphenoid or ethmoidal sinuses were significant predictors of outcome (p < 0.001). Perineural invasion and adjuvant treatment (radiotherapy or chemoradiation) were not associated with prognosis.Conclusion Tumor margin status and tumor site are associated with prognosis in ACC of the paranasal sinuses, whereas perineural invasion is not. Adjuvant treatment apparently has no impact on outcome.  相似文献   
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Objective Chordoma is a locally aggressive tumor. The aim of this study was to assess the efficacy of different surgical approaches and adjuvant radiation modalities used to treat these patients. Design Meta-analysis. Main Outcome Measures Overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS). Results The 5-year OS and PFS rates of the whole cohort (n = 467) were 86% and 65.7%, respectively. The 5-year DSS for patients who underwent open surgery and endoscopic surgery was 45% and 49%, respectively (p = 0.8); PFS was 94% and 79%, respectively (p = 0.11). The 5-year OS of patients treated with surgery followed by adjuvant radiotherapy was 90% compared with 70% of those treated by surgery alone (p = 0.24). Patients undergoing partial resection without adjuvant radiotherapy had a 5-year OS of 41% and a DSS of 45%, significantly lower than in the total-resection group (p = 0.0002 and p = 0.01, respectively). The complication rates were similar in the open and endoscopic groups. Conclusions Patients undergoing total resection have the best outcome; adjuvant radiation therapy improves the survival of patients undergoing partial resection. In view of the advantages of minimally invasive techniques, endoscopic surgery appears an appropriate surgical approach for this disease.  相似文献   
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Ricin, a plant-derived exotoxin, inhibits protein synthesis by ribosomal inactivation. Due to its wide availability and ease of preparation, ricin is considered a biothreat, foremost by respiratory exposure. We examined the in vivo interactions between ricin and cells of the lungs in mice intranasally exposed to the toxin and revealed multi-phasic cell-type-dependent binding profiles. While macrophages (MΦs) and dendritic cells (DCs) displayed biphasic binding to ricin, monophasic binding patterns were observed for other cell types; epithelial cells displayed early binding, while B cells and endothelial cells bound toxin late after intoxication. Neutrophils, which were massively recruited to the intoxicated lung, were refractive to toxin binding. Although epithelial cells bound ricin as early as MΦs and DCs, their rates of elimination differed considerably; a reduction in epithelial cell counts occurred late after intoxication and was restricted to alveolar type II cells only. The differential binding and cell-elimination patterns observed may stem from dissimilar accessibility of the toxin to different cells in the lung and may also reflect unequal interactions of the toxin with different cell-surface receptors. The multifaceted interactions observed in this study between ricin and the various cells of the target organ should be considered in the future development of efficient post-exposure countermeasures against ricin intoxication.  相似文献   
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The phenomenon of acute cholecystitis complicating an unrelated operation has been reported with increasing frequency, and may be preceded by a variety of operative procedures and a lack of previous biliary tract symptoms. Among eight such patients treated by us, seven developed acute cholecystitis postoperatively, and in one it was discovered during operation for bleeding duodenal ulcer. Two patients had undergone wide excision of the breast; two, highly selective vagotomy; one, nephrolithotomy; one, truncal vagotomy and gastroenterostomy; and one, left hemicolectomy and colostomy. In three patients, urgent cholecystectomy was performed, and four were treated conservatively with subsequent elective cholecystectomy. Histopathological studies revealed acute and chronic cholecystitis in all eight patients and cholelithiasis in four. One patient died in septic shock. Numerous contributing factors have been suggested, including hypovolemia and biliary stasis, as well as the presence of stones. It would appear that chronic cholecystitis or other biliary pathology, as found in our eight patients, is a major factor in the development of this manifestation.  相似文献   
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