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1.
Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively.  相似文献   
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本文采用超凝胶柱层析法分离纯化日本血吸虫成虫31/32KD抗原。分离的抗原经银染色及免疫印迹法分析证明已达免疫纯及生化纯级。该抗原PAS染色呈阴性,经过碘酸钠处理后不失去活性,在琼脂糖凝胶电泳中趋向阳极。鉴于血吸虫成虫31/32KD组分是一种主要血清学抗原,它的分离纯化为改进和标化血吸虫病的诊断提供了条件。  相似文献   
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Anaplastic large cell lymphoma (ALCL) comprises 10-15% of childhood non-Hodgkin lymphomas (NHL). Systemic ALCL is highly associated with anaplastic lymphoma kinase (ALK) gene translocations with over-expression of ALK protein. We studied ALK rearrangements using fluorescence in situ hybridisation (FISH) and ALK immunohistochemical staining in 43 paediatric systemic ALCLs. FISH (performed on 35 cases) identified a translocation in 29 cases (83%). Immunohistochemistry identified ALK over-expression in 42/43 cases (97%) with the single ALK-negative case demonstrating an ALK rearrangement by FISH, indicating 100% incidence of ALK translocations.  相似文献   
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AIMS: To determine the prevalence of isolated tumour cells (ITC) in lymph nodes of patients with pathological node-negative (pN0) tumours and to assess their impact on disease-free and overall survival. METHODS: Paraffin embedded lymph nodes from oesophagogastrectomy specimens were examined immunohistochemically using monoclonal anti-cytokeratin antibody (MNF118). Clinical and pathological features were summarised and overall and relapse-free survival were estimated. RESULTS: Isolated tumour cells were detected in 12 of 146 patients (8%), and 24 of 1694 (1%) lymph nodes. With a median follow-up time of 28 months (range 0-160 months), both relapse-free and overall survival were significantly (p<0.05) associated with the presence of ITC in pN0 lymph nodes. There was no significant difference in the prevalence of ITC between patients who underwent multimodal therapy and those treated with surgery alone. CONCLUSIONS: ITC in pN0 lymph nodes may be less frequent than previously considered, but their presence is associated with poorer outcomes compared with true node negative disease.  相似文献   
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Solitary fibrous tumor (SFT) is rare mesenchymal neoplasm that has been originally and most often documented in the pleura. Recently, the ubiquitous nature of the SFT has been recognized with reports of involvement of numerous sites all over the body such as: upper respiratory tract, somatic tissue, mediastinum, head, and neck. Less than 10 cases SFT of breast have been reported. Herein, we presented a 52-year-old Asian female with SFT of breast, this tumor showed predominant malignant features. To our knowledge, SFT of breast with such malignant evidence is extremely rare.  相似文献   
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The formation of protease-resistant prion protein (PrPsc) is considered to be an early event in the pathogenesis of Creutzfeldt-Jakob disease (CJD) and hence its demonstration in brain biopsies by immunohistochemistry is considered diagnostic. We analysed eight brain biopsies from the frontal cortex collected from different parts of India from cases diagnosed as CJD on clinical and pathological grounds for the expression of prion protein (PrP). The duration of illness in these cases varied from 2 months to 1 year. Immunohistochemistry was carried out on paraffin sections using two different clones (KG9 and 3F4) of monoclonal antibodies to PrP. Although all eight cases showed classical features of spongiform encephalopathy of varying severity, only five of the eight cases revealed PrP(sc) in the brain tissue. The immunolabelling was focal and all areas with spongiform change were not labelled. A temporal evolution in the staining pattern was evident - particulate diffuse labelling (synaptic type) in early stages (2 months), perivacuolar deposits in intermediate stages (5-6 months), and dense plaques in late stages (12 months).  相似文献   
9.
The projection from the rat's superior colliculus (SC) to the lateral posterior nucleus of the thalamus (LP) has previously been described as arising from a morphologically homogeneous population of neurons in the stratum opticum (SO). The present study combined immunocytochemistry with retrograde tracing and lesion techniques to determine whether or not the SC → LP projection arose from neurons that were also neurochemically homogeneous. The combination of retrograde tracing and immunocytochemistry with an antibody directed against calbindin-D 28K (CBD) showed that 64.4% of the neurons that project from SC to LP contain this calcium-binding protein. Retrograde tracing and immunocytochemistry for adenosine deaminase (ADA) showed that a smaller number of tecto-LP cells (15.7%) were immunoreactive (IR) for this enzyme. Moreover, nearly all (93.0%) of the ADA-IR tecto-LP cells also contained CBD-IR. Adenosine deaminase-IR axons in LP were restricted to the dorsomedial portion of the nucleus and their density was substantially reduced after ablation of the ipsilateral superficial SC laminae. The lateral posterior nucleus contained numerous CBD-IR cells and fibers throughout its extent and it was thus difficult to determine the extent to which the extra-perikaryal CBD-IR in this nucleus was dependent upon the tecto-LP pathway. Nevertheless, destruction of the ipsilateral SC did reduce the density of CBD-IR in LP. These results suggest that the SC → LP projection in rat arises from at least four neurochemically distinct cell groups: (1) those that contain CBD, (2) those that contain both CBD and ADA, (3) a very small population that contains only ADA, and (4) a group that is not recognized by either of these markers. Our results further suggest that ADA containing fibers may have a more restricted terminal distribution in LP than axons that contain only CBD. © 1993 Wiley-Liss, Inc.  相似文献   
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