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81.
Activation mechanisms of B-1 (Ly-1 B) cells have been suggested to be different from those of conventional B cells. To assess the role of various interleukins (IL) in the activation of B-1 cells, we injected IL-4, IL-5 or IL-10 into nonanemic anti-red blood cells (RBC) autoantibody-transgenic mice, in which conventional B cells are clonally deleted but peritoneal B-1 cells persist without secreting Ig. Intraperitoneal or intramuscular injection of IL-5 or IL-10, but not IL-4, increased the number of antibody-producing peritoneal B-1 cells by four- to five-fold, resulting in increased anti-RBC serum autoantibody and induction of hemolytic anemia. These results suggest that IL-5 or IL-10 may play an important role in the terminal differentiation of B-1 cells into antibody-producing cells in vivo.  相似文献   
82.
Tenosynovial thickening within the confined space of the carpal tunnel is thought to be the cause of the carpal tunnel syndrome (CTS). However, little is known about the pathological mechanism of tenosynovial thickening. In this study, the role of prostaglandin E(2) (PGE(2)) and vascular endothelial growth factor (VEGF) (two representative molecules that can induce oedema by increasing vascular permeability) was analysed in CTS by using immunohistochemistry and enzyme-linked immunosorptive assay (ELISA). Expression of these molecules was compared with the patients' clinical histories and a temporary increase in production of these molecules was found in cells within the vessels and synovial lining during the intermediate phase of the syndrome when the histology of the tenosynovium changes from oedematous to fibrotic. Statistical analysis clearly demonstrated that there is a close correlation between the expression of PGE(2) and VEGF. Furthermore, immunohistochemical analysis with anti-proliferating cell nuclear antigen (PCNA) revealed that the area with distinct VEGF expression closely matched the area where endothelial cells, vascular smooth muscle cells, and synovial lining cells proliferate. In contrast, despite marked alteration in the extracellular matrix (ECM) component of the tenosynovium, the fibroblasts responsible for most ECM framework production do not proliferate during any phase of CTS. Histological analysis demonstrated that angiogenesis takes place only during the intermediate phase. Since clusters of capillaries and arterioles are often surrounded by type III collagen-rich, disorganized, degenerate connective tissue, which contains fewer fibroblasts than normal, angiogenesis appears to take place as a part of a regenerative reaction that results in fibrosis. These findings strongly indicate that both PGE(2) and VEGF are expressed in the tenosynovium in CTS during the intermediate phase and induce the histological changes seen in the tenosynovium.  相似文献   
83.
A high incidence of renal lesions (120 of 164) was confirmed in Mastomys. As high as 86.4% of the tumor-bearing cases developed renal lesions, while 50.8% of animals without tumors were involved by such lesions. Glomerulonephritis was the most frequent with an incidence of 88.3% of the cases. An increase of the mesangial matrix was the initial form. Almost one-third of glomerulonephritis cases were complicated by pyelonephritis and hydronephrosis. Tumor-bearing cases had more advanced lesions in an average severity, although a half of them had only mild changes. Immunohistochemical studies revealed localization of globulins and beta 1C along the walls of the glomerular tufts suggesting deposition of immune complexes. Nodular homogenous deposits in close contact to the basement membrane were ultrastructurally evidenced in the glomeruli. A tiny adenoma was found in a male case with stomach tumor. ACTA PATH. JAP. 20: 311 - 325, 1970.  相似文献   
84.
In freely moving rats, effects of unilateral haloperidol injection into the substantia nigra were monitored with in vivo voltammetry in the bilateral striata. The electrochemical responses at 120 mV versus Ag-AgCl, reflecting mainly a level of 3,4-dihydroxyphenylacetic acid (DOPAC), increased both in the striata within 1.5 h after 5 μg of haloperidol treatment. In the experiments of high-performance liquid chromatography with electrochemical detection, the ratio of DOPAC to dopamine in the striata significantly increased at 2.75 h after drug treatment. These data support the idea that unilateral injection of haloperidol into the substantia nigra in freely moving rats increases dopamine turnover in the bilateral striata.  相似文献   
85.
A case of adrenal pheochromocytoma Is reported characterized by polygonal basophilic granular cells of benign type, plump eosinophilic granular cells of transitional type, and spindle-shaped cells of malignant type. In the primary tumor the neoplastic cells of each type revealed a distinctive topographical distribution. All gradations between the latter two varieties of cells were found, especially in the vicinity of the transitional cell area. Multiple metastases were present in the liver and lungs, where only anaplastic spindle-shaped cells could be found. Ultrastructurally, the benign cells contained predominantly large, rather light, secretory granules with a coarsely granulated core. In the malignant cells, the number, size, and intensity of granules varied considerably from cell to cell or even within a single cell. In general, the malignant cells had a higher frequency of smaller granules with electron-dense homogeneous cores. Moderate amounts of noradrenalin but not significant dopamine or adrenalin could be demonstrated from a metastatic nodule In liver. We postulate that this adrenal medullary pheochromocytoma was benign originally and underwent malignant transformation shortly before the patient's death. This is based upon the patient's clinical features and the peculiar structures of the primary tumor.  相似文献   
86.
Thermal rate of polymerization of 4-vinylpyridine (4-VP) was found to increase greatly in the presence of zinc acetate. The occurrence of radical polymerization was confirmed by studying the effects of additives (2.2-diphenyl-1-picrylhydrazyI (DPPH), air and water). Using zinc acetate as catalyst in THF, the order of thermal rate was 4-VP > MVP > 2-VP (no polymerization). It was concluded that the enhancement of the rate of thermal polymerization was not only due to the increase of propagation rate but also due to the thermal production of radicals by the interaction between monomer and metal salts. The influence of zinc salts on the electronic state of vinylpyridines was studied by electronic spectroscopy. The π→π* transition band of 4-VP was observed to shift towards lower energy by complexing the monomer. The amounts of shift of 2-metlyl-5-vinylpyridine (MVP) and 2-vinylpyridine (2VP) were much smaller than those of the 4-VP-complexes. These spectral data were discussed on the basis of the electornic interction of metal ion with ligand as well as the steric effect in complex formation, and were correlated to the thermal polymerizabilities of complexed vinylpyridines.  相似文献   
87.
The effectiveness of the clinical pathway for laparoscopic cholecystectomy was evaluated, and the efficiency of medical care was analyzed. The duration of hospitalization and the number of National Health Insurance (NHI) points for medical service fees were compared between 86 patients treated after introduction of the clinical pathway (pathway group) and 56 patients treated before introduction of the clinical pathway (pre-pathway group). In the pathway group, variance from the pathway occurred in 24 patients (27.9%) due to postponement of discharge in 7 patients, to earlier discharge in 5 patients, and to insertion of a bile duct catheter in 5 patients. Total and postoperative hospitalization times were significantly shorter in the pathway group than in the pre-pathway group (8.0 +/- 1.6 vs 13.7 +/- 9.0 days, p<0.0001, 5.4 +/- 1.1 vs 6.5 +/- 2.2 days, p<0.0001, respectively). In the pathway group, the total number of NHI points was lower and the number of points per day was higher. By simulation, the total number of NHI points for the 5-day pathway (discharge on postoperative day 3 or earlier) was significantly lower than that for the current 7-day pathway. Moreover, the weekly profit per bed with the 3-day pathway (discharge on postoperative day 1) was more than twice that with the current pathway. The results suggest that the clinical pathway for laparoscopic cholecystectomy is beneficial for patients and useful for the introduction of diagnosis procedure combination in our hospital.  相似文献   
88.
A rare case of high-grade surface osteosarcoma of the left ilum is reported. Trephine biopsy performed on a 31-year-old woman suffering from a huge tumor of the left buttock revealed high-grade osteosarcoma, and hemipel-vectomy was undertaken. The surgical specimen showed that the tumor was present on the surface of the left ilium. Ten months after the operation, the patient died of brain metastasis. From these results, we considered this case to be one of high-grade surface osteosarcoma. ACTA PATHOL JPN 38: 235 -240, 1988.  相似文献   
89.
In bone marrow, hematopoiesis is thought to depend on special microenvironments known as niches that maintain blood cells. However, the identity of niches and interaction of blood cells with niches remain poorly understood. Here we identify stage-specific cellular niches for B lymphopoiesis. The earliest precursors, pre-pro-B cells and end-stage B cells, plasma cells require CXC chemokine ligand (CXCL)12. CXCL12-expressing cells are a small population of stromal cells, scattered throughout bone marrow and located some distance from the cells expressing interleukin (IL)-7. Multipotent hematopoietic progenitors are attached to the processes of CXCL12-expressing cells and pre-pro-B cells adjoin their cell bodies. Maturer pro-B cells that require IL-7 have moved away and adjoin the IL-7-expressing cells. Plasma cells again seed CXCL12-expressing cells. We demonstrate the B lymphocyte characteristic location and movement between specific niches within bone marrow during development and suggest that CXCL12 maintains the cells in the niche.  相似文献   
90.
To investigate the immunological mechanisms of acquired resistance to tick infestation, interferon gamma (IFN-gamma) deficient mice (IFN-gamma mice) were used to assess interleukin-4 (IL-4) and antibody production levels against tick salivary gland antigen on three successive infestations with Haemoaphysalis longicornis Neumann nymphs. The engorged body weight of the ticks decreased during the second and third infestations. Similar observations were noted in IFN-gamma+/+ mice. However, the engorged body weight of the ticks from IFN-gamma +/+ mice were considerably lower than those from IFN-gamma-/- mice. A marked increase in antibody production during the second and third infestations was observed indicating that IFN-gamma-/- mice could acquire immunological resistance against H. longicornis nymphs. Moreover, IL-4 levels were higher during the first and third infestations but decreased during the second infestation. IL-4 levels were significantly higher in IFN-gamma-/- mice than in IFN-gamma+/+ mice. We have shown here that the statistically significant high IL-4 levels observed in IFN-gamma-/- mice may be a result of type 2 helper cell (Th2) polarization. However, the apparently higher IL-4 levels during the first and third infestations and the notable decline during the second infestation suggest that other cytokines or factors in the host immune system may play a part in regulating IL-4 levels.  相似文献   
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