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Summary Esthesioneuroblastoma (ESTH) is a neuroepithelial-cell-derived neoplasm of the olfactory mucosa composed of homogeneous small round cells which contain neurosecretory granules. Melanin has been detected in such tumours only occasionally. Here we describe a new case of ESTH with divergent differentiation. The primary neoplasm was found in a 67 year-old female, involving the left nasal and maxillary sinus; she died of cerebral metastasis ten months after diagnosis. Histologically only small round cells were seen, with S-100 and NSE positivity. Electron microscopy revealed neurosecretory granules and filaments, as well as the occasional presence of melanosomes. A nude mice xenograft line has been established, and is presently in its ninth transfer. Two cell types are present: small round-to-spindle shaped cells with neural features, and large epithelial-like ones. Both immunohistochemistry and electron microscopy confirm this dual differentiation, with the presence of membrane-bound dense-core neural secretion, as well as melanosomes of neuroectodermal origin. Additionally, an in vitro cell line has been established. Cytogenetic analysis confirmed the presence of both malignant human melanoma patterns; non-random abnormalities in chromosomes 1 and 6, extra copies of chromosome 7. Duplication of the long arm of chromosome 14, as seen in olfactory neuroblastoma, is also seen.This work has been supported, in part, with a grant (83/058) from the US-Spain Joint Committee for Scientific and Technological Cooperation (Madrid). This paper was presented, in abbreviated form, at the 72nd Tagung of the Deutsche Gesellschaft für Pathologie, Hannover (24–28 May, 1988)  相似文献   
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PURPOSE: To allow the longitudinal investigation of molecular events associated with the progression of human hepatocellular carcinoma (HCC), we sought to develop a murine model by orthotopic implantation of tumor fragments obtained from patients diagnosed at early stage. EXPERIMENTAL DESIGN: Tumor pieces (2 x 2 mm) were implanted on the liver surface of nu/nu mice. After xenograft growing, subsequent passages were performed to achieve long-term implant viability. Isolation of tumoral hepatocytes was done to establish new cell lines. HCC characteristics, proliferation rate, apoptotic index (terminal deoxynucleotidyl transferase-mediated nick end labeling), and expression of cell-cycle regulators (cyclins E and A, p21(Cip1), p27(Kip1), p16(INK4a), pRb, and p53) were assessed by Western Blot and immunohistochemistry, to correlate them with tumor progression. RESULTS: Five (50%) of the 10 primary HCCs resulted in small slow-growing liver implants. Three of them are viable after 48 months, whereas the remaining two survived for 15 and 13 months. Xenografts throughout passages exhibited a more aggressive phenotype with a poorer degree of differentiation, intense proliferation, moderate apoptosis, cell-cycle deregulation, p53 alterations, microvascular invasion, and dissemination. In one single passage, we observed critical growth delay, which was associated with significant p27(kip1) overexpression. We established the anchor-free growing BCLC-9 cell line from one xenograft. This has gains of chromosomes 7, 5p, 6q, and 9q, is hepatitis B virus-DNA positive, does not secrete alpha-fetoprotein, and has TP53 missense mutations in codons 192 and 242. CONCLUSIONS: The orthotopic implantation of early HCC fragments in nude mice provides a useful model to investigate the mechanisms of human HCC evolution and to establish new cell lines.  相似文献   
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Our objective was to identify individual- and school-level contextual factors related to adherence to the recommendations for physical activity in adolescents. The study used a representative sample of 15,902 students from 328 schools aged 11–18 years participating in the Spanish Health Behaviour in School-aged Children (HBSC) survey 2006. In addition to the student questionnaire, the school management board completed a questionnaire about school-based policies related to physical activity. Adherence to the recommendations was defined as “having carried out moderate and/or vigorous physical activity for at least 60 min a day on five or more days during the last week”. Analysis was undertaken using multilevel logistic regression models. Individual factors associated in a statistically significant way with a higher non-compliance were: being female; being older; immigrants; tobacco smoking; being overweight or obese; low consumption of fruit and vegetables; low level of satisfaction with life; not having a high level of academic achievement; and spending a lot of time studying. The family variables were: not undertaking sports activities with the family; low socioeconomic status; and a low level of satisfaction with family relationships. Compared with schools that have a low level of policies to promote physical activities, those with a high level of promotion had an odds ratio of 0.76 (CI 95 %, 0.61–0.94). In summary, irrespective of personal and family factors, students from schools with better policies of promotion of physical activity showed a higher compliance with the recommendations.  相似文献   
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OBJECTIVE: Almost 30% of gastroenteropancreatic neuroendocrine tumors (GEPET) escape preoperative identification using standard imaging techniques. The goal of this retrospective study is to present our cumulative experience in the assessment of GEPET by preoperative endoscopic ultrasonography (EUS), and to compare it with a literature review. PATIENTS AND METHODS: Thirty-seven patients with suspected specific hormonal syndromes were sequentially examined with US, CT, MRI, angiography, OctreoScan, and radial and sectorial EUS. Sixteen were males (43%) and 21 were females (57%), with a mean age of 61 years (interval: 40-84 a). Of all 37 patients, 27 had 19 endocrine tumors in the pancreas and 14 tumors in their gastrointestinal tract. No tumors were demonstrated in 10 patients, hence they were used as a control group. Of all 37 patients, 24 were operated on or had histological samples collected, with the presence of 26 GEPET (10 carcinoids) being confirmed in 22 patients. RESULTS: EUS sensitivity and diagnostic accuracy were 81% and 78%. Specificity was 80%. All these values were similar to the mean values obtained from the literature review. Three pancreatic rumors smaller than or equal to 1 cm (insulinomas) were detected, which had escaped diagnosis with previous US, CT, and MRI studies. An echoendoscopic examination of the pancreas could not be completed in two cases (5%), a pancreas carcinoid and an already gastrectomized double pancreatic gastrinoma. CONCLUSION: EUS is a good preoperative technique for GEPET detection, and may likely be superior to other imaging techniques in the assessment of small tumors. The usefulness of EUS as a primary exploration after US or HCT has been posited for tumor diagnosis and localization before surgery.  相似文献   
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To analyse if a four-drug combination including two protease inhibitors (PIs) accelerates viral decay and suppression as compared with standard triple therapy in heavily immunosuppressed HIV-1 infected patients, an open label clinical trial was designed. PIs naive patients receiving their first highly active antiretroviral therapy were included if their CD4 cell count was lower than 200/mm3 and their HIV viral load (VL) >100,000 RNA copies/mL. Every patient received two analogues and was randomized in two groups receiving either one PI (saquinavir soft gel capsule) or two PIs (saquinavir + nelfinavir). Viral efficacy (VL <50), time to reach VL <50, viral clearance rate constant and plasmatic elimination half-life were determined. In all, 30 patients were enrolled. No viral variable was significatively improved by the four-drug combination in the short term. No clinical benefit should be expected with a four-drug (two PIs) regimen in patients with low CD4+ cell count and high VL.  相似文献   
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