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21.
A typical case of the D uchenne type of progressive muscular dystrophy with autopsy findings was presented. Changes in the myocardial and smooth muscle of many organs were found, and the skeletal muscles also revealed florid changes.
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation.  相似文献   
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 Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus (HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated with HCMV infection. Received: 24 November 1998 / Accepted: 24 April 1998  相似文献   
24.
A 51 -year-old woman with mixed growth hormone (GH) cell-prolactin (PRL) cell pituitary adenoma is presented. She had clinical signs due to hypersecretion of GH and PRL. Resected tissue was studied immunohistochemically and morphologically. The serial sections revealed that GH and α-subunit were co-localized in most cells, while GH and PRL were localized in different cells.  相似文献   
25.
A case of a rare renal tumor showing characteristic histo-logic features is presented. The patient was a 54 year old female, whose renal tumor was incidentally detected on abdominal ultrasound (US) examination. Ultrasound, computed tomography and angiography findings were consistent with a diagnosis of renal cell carcinoma of the hypovascular type. Left nephrectomy was performed. The tumor, which measured 2.6 times2.6 times 2.5 cm, was located in the left renal cortex, and had a uniformly whitish-yellow cut surface and well-defined margin. Histologically, the tumor was characterlzed by its monomorphous growth pattern and was composed of uniformly small cells arranged in a tubular or rosette-like pattern. The tumor cells had scant cytoplasm and the nuclei were small, round and regular. These histo-logic features resembled the epithelial elements of a metanephric hamartoma in the nephroblastomatosis complex in infants. However, there was no mitosis and cellular atypia was minimal, suggesting benignity. According to these his-tologic features, the diagnosis of metanephric adenoma was made. Its clinicopathologic features are discussed.  相似文献   
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The TGF-1(–/–) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-1(–/–) mice. Heart, lung, liver, and salivary gland from TGF-1(–/–) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-1(–/–) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity.  相似文献   
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29.
The benign epithelial neoplasm liver cell adenoma is rare, especially in childhood. We report 2 such cases, 1 of which was associated with Prader-Willi syndrome. Differential diagnosis of the liver cell adenomas on the basis of histopathologic findings proved difficult and was based on the absence of cellular and nuclear atypia, mitotic activity, and invasive growth. In both cases, immunohistochemical staining demonstrated the nuclear accumulation of beta-catenin, and in 1 case, the tumor cells carried a mutation of the beta-catenin gene. Recently, disregulation of the Wnt/beta-catenin pathway, attributable to abnormalities of the beta-catenin gene, has been reported to be a major event in the development of hepatocellular carcinomas and hepatoblastomas. Our report may be the first to describe the beta-catenin abnormalities in childhood liver cell adenoma. These findings imply that abnormalities of beta-catenin can be an early initiating event in human liver tumorigenesis.  相似文献   
30.
Severe inflammatory responses after major surgeries, trauma, and infection develop multiple organ dysfunction. In the mechanisms of the pathogenesis of these responses, activated neutrophils are thought to be important in terms of their ability to produce various kinds of proteinases, which can degrade various proteins constructing human tissues. Among their proteinases, neutrophil elastase is the strongest serine proteinase secreted from activated neutrophils. Thus, we examined in this study the inhibitory effect and therapeutic efficacy of newly produced recombinant human Kunitz-type proteinase inhibitor (R-020), which coded the second domain of human urinary trypsin inhibitor. R-020 was effective in significantly improving the survival rate after induction of the rat lethal peritonitis model (cecal ligation and punctureinduced septic shock model). We suggest that various serine proteinases are implicated in the pathogenesis of neutrophil-related multiple organ failure and that recombinant human Kunitz-type proteinase inhibitor might be effective in the treatment of these kinds of organ dysfunction.  相似文献   
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