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21.
The ultrastructural patterns of neuroendocrine (NE) differentiated breast carcinomas are analyzed and discussed. Reports in the literature describe wide variations in the size of observed dense-core membrane-bound granules and discrepancies in their interpretation. In the present study 24 cases of breast carcinoma with recognized morphologic, histochemical, and immunocytochemical features of NE tumors were investigated. Five different types of dense-core granules of neurosecretory (NS) type (confirmed by the ultrastructural localization of chromogranin A) and five different cell types were recognized. Some amphicrine cells were found to contain both mucin and NS granules. Another notable ultrastructural feature of breast NE carcinomas was the presence of clear vesicles of presynaptic type, which correlated with expression of synaptophysin.  相似文献   
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Information on genetic changes involved in the progression of gastroenteropancreatic (GEP) endocrine tumours is scanty. On the other hand, the identification of molecular markers of malignancy could be crucial for the prognostic evaluation of these neoplasms, which is hardly predictable on the basis of conventional histological criteria. An association of X-chromosome deletions with malignancy has already been found in gastric endocrine tumours. To investigate this further, a comparative loss of heterozygosity (LOH) analysis was performed on 17 pancreatic endocrine tumours (PETs) and 17 intestinal (ten ileal, six appendiceal, and one rectal) carcinoids from female patients. The relationship of X-chromosome LOH with the ploidy status of the neoplasms was also investigated. LOH was found in six of eight malignant PETs (60% of the informative markers), but was infrequent in the nine benign ones (4.5%). In contrast, although retention of heterozygosity was consistently observed in benign midgut tumours, LOH was infrequent in malignant carcinoids (15%). No correlation was found between LOH and the ploidy status. These results indicate an association between X-chromosome LOH and malignancy in foregut endocrine tumours. The lack of such an association in midgut carcinoids suggests that different molecular mechanisms are involved in the progression of these two categories of endocrine neoplasms, which are otherwise considered to be closely related. These findings emphasize the need for further molecular studies on GEP endocrine tumours, carefully subdivided according to their anatomical site of origin.  相似文献   
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We have identified a novel missense transition (362G→A) in exon 3 of the COL4A5 gene in a male patient with late-onset Alport syndrome. We used non-isotopic single strand conformation polymorphism, heteroduplex analysis, and automated DNA sequencing. The mutation changes a conserved glycine at codon 54 for an aspartic acid (Gly54Asp), which abolishes a BstNI site. Using restriction analysis, we identified the heterozygous carrier status in the two daughters of the proband. Our findings are in keeping with the hypothesis that slower progressive forms of Alport syndrome are more often associated with missense mutations rather than large deletions or frameshifts. This is the first mutation described in the N-terminus triple helical 7S domain of the COL4A5 gene in an Alport syndrome patient.  相似文献   
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Summary 26 patients with astrocytoma grade 11–111, and 36 with malignant glioma (astrocytoma grade IV or glioblastoma) were submitted three days after surgery to a cycle of combination chemotherapy, including BCNU, VCR, PCZ (BVP). Eighteen days after surgery, patients received 40 Gy (astrocytoma grade 11–111) or 45 Gy (malignant glioma) of megavoltage whole-brain irradiation, with an additional boost to the tumor bed of 20 Gy, delivered in 6 weeks. Vincristine was injected weekly during radiotherapy. At the end of radiotherapy, patients received BVP every 6 weeks for at least 8 cycles or until a recurrence or progressive disease. Performance status of grade 1 or 2 was achieved in 15 (60%) and in 5 (20%), respectively, of patients with astrocytoma grade 11–111 after 6 months, and in 6 ps. (29%) and in 9 ps. (42%) after 12 months of follow-up. Only 2 (5.5%) and 18 (64%) patients with malignant glioma achieved a performance status of grade 1 or 2 after 6 months, and these proportions are 6% and 35%, respectively, after 12 months. After a 5-year follow-up, 59% of patients with astrocytoma are still alive, with a median survival time of 60+ months, whereas only 4% of patients with malignant glioma are alive, with a median of 11.2 months.  相似文献   
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The sensitivity of preoperative imaging was evaluated for the localization of insulinomas in 2 series of 54 and 17 patients, respectively. In the first series, diagnosis was obtained with ultrasonography (US) in 14.8%, with computed tomographic (CT) scan in 60%, and with arteriography and/or angio CT scan in 75% of patients. In the second series, US, CT scan, and arteriography were performed preoperatively showing a sensitivity of 53% of one or more of the imaging techniques. The last 17 patients all underwent intraoperative pancreatosonography, and the insulinoma was localized in each. Considering the high reliability of intraoperative ultrasonography, and the high costs and low benefits of other current diagnostic techniques, a new management plan is suggested for patients with a definite laboratory diagnosis of insulinoma.
Resumen La sensibilidad de la imagenología preoperatoria para la localización de insulinomas fue evaluada en 2 series de 54 y 17 pacientes respectivamente. En la primera serie, el diagnóstico fue logrado con ultrasonografía en 14.8%, con escanografía computadorizada en 60%, y con arteriografía y/o angiografía con escanografía computadorizada en 75% de los casos. En la segunda serie, la ultrasonografía, la escanografía computadorizada, y la arteriografía fueron realizadas preoperatoriamente demostrando una sensibilidad de 53% en una o más de las técnicas de imagenología. En los últimos 17 pacientes se realizó pancreatosonografía, la cual permitió la localización del tumor en 100% de los casos.En consideración a la elevada confiabilidad de la ultrasonografía intraoperatoria, y los altos costos y bajo rendimiento de las técnicas corrientes de diagnóstico, se sugiere un nuevo plan de manejo para pacientes con un diagnóstico de laboratorio certero de insulinoma. Se fundamenta en la localización ultrasonográfica intraoperatoria del tumor, la cual puede ser aplicada en los más comprensivos centras médicos.

Résumé La sensibilité de l'imagerie pré-opératoire permettant la localisation des insulinomes a été étudiée dans 2 séries de 54 et 17 sujects. Dans la première série le diagnostic fut posé par l'échographie dans 14.8% des cas, par la tomodensitométrie dans 60% des cas, par l'artériographie et/ou l'angiotomodensitométrie dans 75% des cas. Dans la seconde série, l'échographie, la tomodensitométrie et l'artériographie furent pratiquées avant l'intervention avec une sensibilité de 53% pour l'une ou pour plusieurs techniques. Chez les 17 derniers malades l'échographie opératoire fut systématiquement pratiquée et permit la localisation de la tumeur dans 100% des cas.Considérant la haute fiabilité de l'échographie opératoire, le coût élevé et les faibles résultats des autres techniques de diagnostic, un nouveau plan d'investigation est proposé pour explorer les malades qui présentèrent certains signes biologiques d'insulinome. Il repose sur la localisation per-opératoire de la tumeur par l'échographie, méthode qui peut être pratiquée dans des centres spécialisés.
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BackgroundEndoscopy plays a pivotal role in the management of adverse events (AE) following bariatric surgery. Leaks, fistulae, and post-operative collection after sleeve gastrectomy (SG) may occur in up to 10% of cases.ObjectivesTo evaluate the efficacy and safety of endoscopic internal drainage (EID) for the management of leak, fistula, and collection following SG.SettingRetrospective, observational, single center study on patients referred from several bariatric surgery departments to an endoscopic referral center.MethodsEID was used as first-line treatment for the management of leaks, fistulae, and collections. Leaks and fistulae were treated with double pigtail stent (DPS) deployment in order to guarantee internal drainage and second intention cavity obliteration. Collections were treated with endoscropic ultrasound (EUS)–guided deployment of DPS or lumen apposing metal stents.ResultsA total of 617 patients (83.3% female; mean age, 43.1 yr) were enrolled in the study for leak (n = 300, 48.6%), fistula (n = 285, 46.2%), and collection (n = 32, 5.2%). Median follow-up was 19.5 months. Overall clinical success was 84.7% whereas 15.3% of cases required revisional surgery after EID failure. Clinical success according to type of AE was 89.5%, 78.5%, and 90% for leak, fistula, and collection, respectively. A total of 10 of 547 (1.8%) presented a recurrence during follow-up. A total of 28 (4.5%) AE related to the endoscopic treatment occurred. At univariate logistic regression predictors of failure were: fistula (OR 2.012), combined endoscopic approach (OR 2.319), need for emergency surgery (OR 1.755), and previous endoscopic treatment (OR 4.818).ConclusionEarly EID for the management of leak, fistula, and post-operative collection after SG seems a safe and effective first-line approach with good long-term results.  相似文献   
30.
Acute infectious diarrhea   总被引:1,自引:0,他引:1  
Marignani M  Angeletti S  Delle Fave G 《The New England journal of medicine》2004,350(15):1576-7; author reply 1576-7
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