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51.
In order to clarify the appearance of monocytoid B lymphocytes (MBLs) in abscess-forming granulomatous lymphadenitis (AGL) and the relation between AGL and cat-scratch disease (CSD), 48 cases of AGL were studied histologically. MBLs were present in about 50% of AGL cases. Warthin-Starry (WS) silver stain-positive bacteria, which are the causative agent of CSD, were present in 52.4% of AGL cases with MBLs and 59.2% of AGL cases without MBLs. The appearance of MBLs in AGL was not related to various clinical features, including disease interval from initial lymphadenopathy to lymph node biopsy. Histologically, epithelioid cell clusters appeared in about 70% of MBL-positive AGL cases, but were not observed in MBL-negative AGL. Therefore, a close interaction between MBLs and epithelioid cells in AGL is suggested, and we emphasize that the histological features of some AGL cases resemble those of toxoplasmic lymphadenitis.  相似文献   
52.
An ultrastructural study was undertaken concerning morphological changes within the autografted patellar tendon (PT) after being transplanted to the anterior cruciate ligament (ACL) in mongrel dogs. After 4 weeks, the arrangements of both large and small collagen fibrils in the PT graft became disordered, and the number of inflammatory cells increased. However, the same PT grafts revealed postsurgical signs of newly-produced collagen fibrils around activated fibroblasts at 12 to 24 weeks. At 52 weeks after the transplantation, small collagen fibrils increased in both number and density, showing a remarkable morphological similarity to the collagen fibrils of normal ACL. These data indicate that the characteristics of the PT graft eventually resemble those of a normal ACL. This paper was presented in part at the Combined Meeting of the Orthopedic Research Societies of the USA, Japan and Canada in Banff, Alberta, Canada, October, 1991.  相似文献   
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Benastatins have been isolated as part of a program designed to find microorganism-produced inhibitors of glutathione S-transferase from Streptomyces sp. MI384-DF12. They were purified by chromatography of reversed-phase silica gel, silica gel and Capcell Pak C18 (HPLC) followed by solvent extraction and then isolated as yellow powders. Benastatins A and B have the molecular formulae, C30H28O7 and C30H30O7, respectively. They were competitive with 3,4-dichloronitrobenzene as the substrate, and the inhibition constants (Ki) of benastatins A and B were 5.0 x 10(-6) and 3.7 x 10(-6), respectively.  相似文献   
55.
A 36 year old woman was admitted to our department because of a chest X-ray which showed multiple developing shadows. She underwent bilateral exploratory thoracotomies and a total 5 tumors were resected and pathologically diagnosed as benign metastasizing leiomyoma, the largest of which was positive for the progesterone receptor and negative for the estrogen receptor. A histogram of this tumor using a flow cytometer showed a diploid pattern and 4.6 percent of the S phase which was not more than that of a leiomyoma of the uterus from another patient. Two months later, she underwent a hysterectomy and bilateral salpingo-oophorectomy for treatment of the positive progesterone receptor in the pulmonary lesions. The resected uterine myoma and normal myometrium showed positive estrogen and progesterone receptors. For the subsequent 28 months she has been free of any further symptoms. Benign metastasizing leiomyoma of the uterus is a rare disease and very interesting because of its histological benignity and hormonal dependency. However, according to the literature, it is often confused in entity due to the fact that normal lung tissue also possesses hormone receptors. Considering our data on hormone receptors, it is rational to think that multiple leiomyomatous lesions in the lung should only be diagnosed as benign metastasizing leiomyomas when they possess positive estrogen and progesterone receptors.  相似文献   
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A 72-year-old male was admitted because of right lower quadrant pain, Barium enema and total colonoscopy disclosed multiple colon cancers and sequentially, a subtotal colectomy was performed. The resected specimen demonstrated 3 advanced carcinomas and an adenomatous cancer with additional multiple polyps. Investigation of his family history revealed that his mother and his elder sister had died of uterine cancer, and that his elder brother, his nephew, and his niece had been operated on for colorectal cancer. We thus supposed a case of "Cancer Family Syndrome" presenting multiple neoplasms of the colon.  相似文献   
58.
Electron microscopic and immunohistochemical studies were carried out on materials obtained from three patients of gamma heavy chain disease ( λ -HCD). Electron microscopically, proliferating cells showed various stages of maturation from immunoblast to plasma cell, and the majority of proliferating cells were proplasmacytes and plasma cells. From the intracytoplasmic immunoglobulin studies by immunoperoxidase method (PAP method) and electron microscopical enzyme-labeled antibody technique, proliferating cells, such as the immunoblast, plasmablast, proplasmacyte, and plasma cell, showed positive reaction to anti- λ -heavy chain serum and anti-Fc fragment (IgG) serum, and also in a third case with Bence Jones protein, proliferating cells showed positive reaction to anti-K light chain serum. We would conclude that proliferating cells in λ -HCD might be a single clone proliferation of B-cell synthesizing λ -HCD protein, and the predominant proliferation cells are proplasmacytes and plasma cells situated near mature plasma cells in the B-cell line.  相似文献   
59.
A novel, proinflammatory cytokine, interleukin (IL)-18 production was detected in the medium of human monocytes treated with 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase inhibitors, pravastatin, and fluvastatin (0.1 and 1 muM) but not with the statin-derived lymphocyte function-associated antigen-1 (LFA-1) inhibitor LFA703, which did not inhibit HMG-CoA reductase. Pravastatin and fluvastatin also induced the production of IL-18, tumor necrosis factor alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in human peripheral blood mononuclear cells (PBMC) in contrast to LFA703. IL-18 production by PBMC is located upstream of the cytokine cascade activated by these statins. The IL-18-induced cytokine production was demonstrated to be dependent on adhesion molecule expression on monocytes. In the absence and presence of lower concentrations (0.1 and 1 ng/ml) of IL-18, pravastatin and fluvastatin inhibited the expression of intercellular adhesion molecule (ICAM)-1 and induced the expression of CD40, whereas LFA703 had no effect. In the presence of higher concentrations (5, 10, and 100 ng/ml) of IL-18, pravastatin, fluvastatin, and LFA703 similarly inhibited the expression of ICAM-1 and CD40 as well as the production of IL-12, TNF-alpha, and IFN-gamma in PBMC. The effects of pravastatin and fluvastatin but not LFA703 were abolished by the addition of mevalonate, indicating the involvement of HMG-CoA reductase in the action of pravastatin and fluvastatin. Thus, the effects of LFA703 were distinct from those of pravastatin and fluvastatin in the presence of lower concentrations of IL-18. It was concluded that LFA703 has the inhibitory effect on an IL-18-initiated immune response without any activation on monocytes.  相似文献   
60.
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