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1.
Cutaneous carcinoma histopathologically resembling nasopharyngeal carcinoma has been termed lymphoepithelioma-like carcinoma of the skin. We present an additional example of this rare cutaneous neoplasm that was located on the left temple of an 83-year-old woman. Serology for Epstein-Barr virus was negative, and exploration of the nasopharyngeal region disclosed no abnormalities. Histopathologically, the neoplasm consisted of a relatively well-circumscribed, dermal-hypodermal nodule composed of irregular aggregates of epithelial cells with vesicular nuclei, some of them in mitosis, and scant cytoplasm. A dense lymphocytic infiltrate was present within the neoplastic aggregates, obscuring the epithelial component, and at scanning magnification, the lesion closely resembled cutaneous lymphoma or pseudolymphoma. There was local sebaceous differentiation. Immunohistochemistry showed positivity in the epithelial component for AE1/AE3 and AEB-903 cytokeratins and negativity for 8–18 cylokeratins. The inflammatory infiltrate was positive for leukocyte common antigen, UCHL-1, L-26, Leu-22, and OPD-4 in variable proportions. Scattered cells within this inflammatory infiltrate were also positive for S-100 protein, vimentin, HAM-56, and MAC-387. In situ hybridization investigations for the presence of Epstein-Barr virus genomic DNA yielded negative results. Lymphoepithelioma-like carcinoma of the skin is a distinct cutaneous neoplasm of unknown histogenesis, although some foci of adnexal differentiation have been found in some specimens. The possibility of cutaneous metastasis from occult nasopharyngeal carcinoma should be ruled out.
Requena L, Sánchez Yus E, Jiménez E, Roo E. Lymphoepithelioma-like carcinoma of the skin: A light-microscopic and immunohistochemical study.  相似文献   
2.
The characteristic ratios of three samples of poly(1-hexadecene) with different tacticities were evaluated from intrinsic viscosity and molecular weight data obtained with a size exclusion chromatograph with dual (concentration plus viscosity) detector. No significant differences were found for the characteristic ratio in the studied range of tacticities. Theoretical calculations for the unperturbed dimensions were also performed for these samples by using the rotational isomeric state model, and compared with the experimental results.  相似文献   
3.
Values of the dielectric loss tangent were obtained as a function of temperature for poly(pentamethylene sulfide) (P5MS) and poly(1,3-dithiocane) (PDTC). Both P5MS and PDTC exhibit a β absorption, located in the vicinity of their respective glass transition temperatures, ?105°C and ?73°C, which is believed to be associated with micro-Brownian motions in the amorphous phase of the crystalline polymers. The glass-rubber transitions of the polymers are discussed in terms of the flexibility of the chains, as expressed by their conformational partition functions and entropies.  相似文献   
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The Senegalese sole (Solea senegalensis) is a high value market flatfish, which aquaculture is compromised by severe reproductive problems; these are mostly found in soles hatched and raised in captivity (F1 generation). To gain knowledge on the reproductive dysfunctions observed in cultured (F1) Senegalese sole, this work aimed at developing a specific vitellogenin (VTG) ELISA, for the measurement of plasma VTG levels in this species. Profiles of VTG were correlated with those of sexual steroids and spawning performance of an F1 broodstock, during three consecutive years. The Senegalese sole VTG (ssVTG) was purified by precipitation with MgCl(2)-EDTA and anion-exchange chromatography and showed a molecular mass of 172 kDa, by SDS-PAGE. Specific antibodies were obtained and used to develop a competitive ELISA, which had a sensitivity of 3.6 ng ml(-1), and inter- and intra-assay coefficients of variation of 9.5% (n=29) and 6.7% (n=12), respectively. Annual profiles of plasma VTG showed a major peak at pre-spawning, and a second minor rise around autumn, which mirrored plasma profiles of both estradiol (E(2)) and testosterone (T) levels. Spontaneous spawning occurred every year in the spring season, but no fertilized eggs were obtained. In conclusion, this study described, for the first time, the purification and development of a sensitive and specific ELISA for Senegalese sole VTG. The endocrine and spawning data suggested that F1 female broodstock showed normal VTG and steroid releasing profiles in captivity with occurrence of spontaneous spawning, but no fertilization of the eggs was recorded.  相似文献   
7.
Pheochromocytoma is a catecholamine-producing tumor and a rare cause of hypertension. Most cases are intra-adrenal and intrapericardial pheochromocytomas are extremely uncommon. We report the case of a 46-year-old woman with a 1-year history of hypertension, in which a right atrial pheochromocytoma was detected after a hypertensive crisis. 131I-metaiodobenzylguanidine scintigraphy and magnetic resonance imaging established the diagnosis. The tumor was successfully resected using cardiopulmonary bypass and the right atrium was reconstructed using bovine pericardium.  相似文献   
8.
Sweet's syndrome, or febrile neutrophilic dermatosis, is a process characterized by fever, red tender plaques, neutrophilia and neutrophilic dermal infiltrate with papilar edema in the absence of vasculitis. The association with intestinal inflammatory disease is inusual, a new case associated with ulcerative colitis is reported, and we perform a literature review of Sweet's associated intestinal inflammatory disease.  相似文献   
9.
INTRODUCTION AND OBJECTIVES: Five percent of the patients with hypertrophic obstructive cardiomyopathy (HOCM) have symptoms unresponsive to medical treatment and are candidates for invasive therapy. The objective of this study was to analyze our results with surgical treatment of HOCM during the last 10 years. PATIENTS AND METHOD: Between July 1993 and January 2004 26 patients with HOCM refractory to drug therapy were operated on. An extended septal myectomy was performed, in combination with anterior mitral leaflet plication in 19 cases (73%) and with mitral valve replacement in 5 (19%). Evolution of the grade of dyspnea, left ventricle outflow tract gradient (LVOTG), mitral regurgitation, and systolic anterior motion after surgery was analyzed. RESULTS: Mean follow-up was 63 (37) months. After surgery, a significant reduction in LVOTG (from 96.5 to 19.5 mmHg; P<.001), grade of mitral regurgitation (from 2.54 to 0.69; P<.001) and systolic anterior motion (from 2.92 to 0.23; P<.001) was achieved, which led to improvement in functional class. Hospital mortality and need for pacemaker implantation due to complete heart block after surgery was 3.8% (n=1). There were no cases of iatrogenic ventricular septal defect or mitro-aortic valve injury. Actuarial survival at 5 years was 96% (4%). CONCLUSIONS: Surgery in patients with HOCM yields great clinical improvements with low morbidity and mortality. Simultaneous intervention for both myocardial and valvular components of the disease allows not only reduction in the LVOTG but also correction of mitral regurgitation and abolition of systolic anterior motion.  相似文献   
10.
Retrospective population-based studies showed that in cancer patients venous thromboembolism (VTE) is associated with reduced survival. Master Oncology is a multicenter study in patients with solid advanced cancer aimed at assessing (1) risk factors for VTE using a case–control design, and (2) survival in cases (patients with VTE) and controls (patients without VTE). Survival data were prospectively collected for at least 10 months. Overall, 237 cases and 339 controls were included in the analysis. The following factors were found to be associated with an increased risk of VTE: body mass index (BMI; OR 2.02; 95 % CI 1.31–3.12 for ≥26 vs. <23 kg/m2), ECOG score (OR 2.14; 95 % CI 1.47–3.11 for grade 1, and 3.32; 95 % CI 1.64–6.00 for grade 2–3, compared to grade 0) and recent diagnosis of cancer (OR 1.90; 95 % CI 1.33–2.71 for <12 vs. ≥12 months). After an average prospective observation of 8.3 months, 136 cases (57.4 %) and 127 controls (37.5 %) died with a median survival of 8.7 (95 % CI 7.5–10.9) and 14.3 months (95 % CI 12.2–18.7), respectively, (Wilcoxon = 27.72, p < 0.001; multivariate hazard ratio 1.55; 95 % CI 1.21–2.00). Median survival time was reduced for both patients with symptomatic (Wilcoxon = 35.22, p < 0.001) and asymptomatic VTE (Wilcoxon = 4.63, p = 0.031). Patients with advanced solid cancer, high BMI, high ECOG score, and recent diagnosis of cancer are associated with an increased risk for VTE. Patients with both symptomatic and asymptomatic VTE have a reduced survival compared to those without VTE.  相似文献   
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