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Two cases of small-cell carcinoma of the ovary in the ascitic fluid and peritoneal/pelvic washings of a 30- and 28-yr-old woman, respectively, are presented and discussed. Smear preparations from the ascitic fluid showed loose clusters and single malignant cells with scant cytoplasm and nuclei with smooth to irregular nuclear membranes, granular chromatin, and small nucleoli. In the second case peritoneal/pelvic washing specimens contained clusters and single malignant cells with a moderate amount of cytoplasm and nuclei with smooth nuclear membranes, granular, clumped chromatin, and prominent nucleoli. Histology confirmed the diagnosis of small-cell carcinoma of the ovary. These are the first reported cases of this rare ovarian neoplasm present on fluid cytology. Its differentiation from other small-cell neoplasms on peritoneal fluid cytology from young women is discussed. Diagn Cytopathol 1994; 11:266–270. © 1994 Wiley-Liss, Inc.  相似文献   
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RB1 is the gene responsible for retinoblastoma, the most common malignant intraocular tumor of infancy and early childhood. There are no reports about this gene in Ecuadorian populations, and only a few studies have been published in Latin America about this subject. There is a spectrum of more than 370 mutations described in the RB1 gene mutation database (http://www.d-lohmann.de/Rb/mutations.html), and alterations have been found in 25 of the 27 exons. During the exon-by-exon analysis of 31 tumor and blood samples from Ecuadorian patients, we found two new mutations and three novel polymorphisms. One of the polymorphisms is located in intron 26 where no alterations of the gene have been described previously. The polymorphisms were found in all of the patients tumor samples, but not in normal population, suggesting there might be a relationship between these polymorphisms and the development of retinoblastoma in the Ecuadorian population.The nucleotide sequence data reported are available in the GenBank database under the accession numbers: AY243567, AY260472, AY260473, AY273783  相似文献   
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Lymph-borne immunoblasts were fixed in dilute glutaraldehyde and then treated with saponin. This treatment made most parts of the cells permeable to ferritin, so that anti-immunoglobulin (Ig) antibodies which had been conjugated to horse radish peroxidase (HRP) had no difficulty in gaining access to Ig which thus could be demonstrated at an ultrastructural level. Best results were obtained by fixing the cells in 0.1% glutaraldehyde for 7 min and then treating them with a 1% solution of saponin for 100 min at 55 degrees C before exposing them to the Ig-HRP conjugate. The method yielded reproducible results and although it causes a small amount of ultrastructural damage, it may be of value in detecting a variety of intracellular antigens.  相似文献   
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Introduction and importanceSolid organ transplantation has evolved along with dramatic advancements in definitive treatment for irreversible and uncompensated organ failure. Transplanted organ survival has improved as a result of reduced allograft rejection. However, negative long-term outcomes which were largely due to the adverse effects of rapidly evolving immunosuppressive regimens are still evident. The emergence of malignancies following prolonged exposure to immunosuppression treatment has affected the quality of life in transplant recipients. They are approximately one hundred times more likely to develop squamous cell carcinoma (SCC) compared to the general population and the incidence of malignant melanomas, basal cell carcinomas, and Kaposi’s sarcomas are also on the rise. The incidence of de novo malignancies ranges from 9 to 21% and is commonly seen in the skin and the lymphoreticular system in these patients.Case presentationA 78-year-old male presented with a lump in the right axilla, which had grown in size over a 4-week period. Patient had received a cardiac transplant 9 years prior and was on a regimen of Tacrolimus and Mycophenolate Mofetil since then.Clinical discussionFollowing 4 years of immunosuppression therapy, the patient developed a non-healing ulcer on his right forearm and the biopsy confirmed SCC. The recent biopsy performed on the new axillary lump also confirmed SCC. Iatrogenic immune suppressive treatment is associated with the occurrence of de novo, non-melanoma skin cancers in the solid organ transplant recipients and this necessitates early and comprehensive cancer surveillance models to be included in the pre and post-transplant assessment.ConclusionAdvances in immunology suggest that peripheral blood mononuclear cell sequencing and immune profiling to identify immune phenotypes associated with keratinocyte cancers allow us to recognize patients who are more susceptible for SCC following organ transplantation and immunosuppression.  相似文献   
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