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1.
To elucidate the effect of fibroblast growth factor on the phenotypical conversion of fibroblasts to mesothelial cells, both immunohistochemical and ultrastructural examinations were carried out on cultured spheroids that were composed of fibroblasts obtained from the parietal pleura of rats with and without addition of antifibroblast growth factor receptor antibody. In the present study, antifibroblast growth factor receptor antibody was employed to block the effect of the autocrine component of fibroblast growth factor in the culture medium. Phenotypical conversion from fibroblast to mesothelial cells was clearly blocked in the experimental group, to which culture medium had been added with antifibroblast growth factor receptor antibody, whereas the control group, cultured without addition of antifibroblast growth factor receptor antibody, showed phenotypical conversion of fibroblasts that was confirmed by the development of macula adherens, microvilli, and positive expression of cytokeratin. These results indicate the possibility that fibroblast growth factor plays a key role in the process of phenotypic conversion of fibroblasts to regenerated mesothelial cells.  相似文献   
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A diagnosis of sarcoidosis should be substantiated by pathological means in order to thoroughly exclude other diseases. The role of real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of sarcoidosis has not been reported. The purpose of the present study is to evaluate the diagnostic yield of EBUS-TBNA in demonstrating the pathological features of sarcoidosis. In total, 65 patients with suspected sarcoidosis, with enlarged hilar or mediastinal lymph nodes on computed tomography, were included in the study. Patients with a suspected or known malignancy or previously established diagnosis of sarcoidosis were excluded. Convex probe endobronchial ultrasonography integrated with a separate working channel was used for EBUS-TBNA. Surgical methods were performed in those in whom no granulomas were detected by EBUS-TBNA. Patients were followed up clinically. EBUS-TBNA was performed on a total of 77 lymph node stations in 65 patients. A final diagnosis of sarcoidosis was made for 61 (93.8%) of the patients. The remaining four patients were diagnosed as having Wegener's granulomatosis (n=1) or indefinite (n=3). In patients with a final diagnosis of sarcoidosis, EBUS-TBNA demonstrated noncaseating epithelioid cell granulomas in 56 (91.8%) of the patients. No complications were reported. Endobronchial ultrasound-guided transbronchial needle aspiration proved to be a safe procedure with a high yield for the diagnoses of sarcoidosis.  相似文献   
4.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
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The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.  相似文献   
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Staging of esophageal carcinoma in vitro with 4.7-T MR imaging   总被引:4,自引:0,他引:4  
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A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993.  相似文献   
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Changes in the distribution of hyaluronic acid in the developing human retina were investigated histochemically with alcian blue staining and theStreptomyces hyaluronidase digestion method using 56 human embryos and fetuses ranging from 5 to 41 weeks of gestational age. Hyaluronic acid was first detected in the inner layer of the retina at 12 weeks. The site of accumulation extended towards the outer layer by 20 weeks. At the neonatal stage, longitudinal fibers, possibly the processes of Müller cells, were proved to contain hyaluronic acid. These findings suggest that Müller cells produce hyaluronic acid transiently from 12 weeks’ gestation to the neonatal stage.  相似文献   
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