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51.
多发性脑梗塞痴呆动物模型评价 总被引:1,自引:0,他引:1
多发性脑梗塞痴呆模型大鼠可出现行为学、病理生理学、生化代谢、神经递质、血液流变学、基因表达等多方面改变,且病理形态学表现与临床上多发性脑梗塞痴呆相似,可以用作血管性痴呆的实验研究。但复习以往有关文献研究发现,该模型仍有待于进一步完善,以期更好地应用于基础研究,保证对药物抗血管性痴呆作用评价及作用机制诠释的准确性。 相似文献
52.
Granulocyte-macrophage colony stimulating factor (GM-CSF) modulates various functions of monocytes/ macrophages including antigen-presenting capacity. Recently it was found that astrocytes produce GM-CSF in the central nervous system (CNS) and that GM-CSF can induce proliferation and morphological changes of microglia. Here we show that GM-CSF can down regulate the interferon-γ-mediated induction of major histocompatibility complex (MHC) class II antigens in microglia, but not in astrocytes. GM-CSF pretreatment completely prevents myelin basic protein-specific T cell proliferation induced by microglia but not astrocytes. GM-CSF did not affect the cell surface expression on microglia of either MHC class I or cell adhesion molecules. The inhibition of microglial MHC class II expression and antigen-presenting function is specific for GM-CSF, as treatment with a different CSF (interleukin-3) did not modulate microglial phenotype or functional capacity. These data suggest that GM-CSF might be involved in the regulation of immune responses within the central nervous system. 相似文献
53.
H. Konno T. Yamamoto Y. Iwasaki T. Saitoh H. Suzuki H. Terunuma 《Acta neuropathologica》1989,77(5):472-479
Summary Monoclonal antibodies (MRC OX-6 and OX-17) recognized three types of cells expressing Ia antigen during the course of acute experimental allergic encephalomyelitis (EAE) in rats. In earlier stages of the disease, in animals with or without paralysis, Ia antigens were mostly localized to subarachnoidal and perivascular lymphocytic and histiocytic cell infiltrates, possibly serving as antigen-presenting cells. On the other hand, in convalescent rats, Ia antigens were expressed in a large number of cells with dendritic processes heavily populating the spinal gray matter. The appearance of these Ia-expressing cells in the convalescent stage coincided with the development of degenerating axon terminals in the spinal gray matter. These Ia-expressing cells possessed morphological features characteristic of microglia and were positive for ML-1 lectin but did not express glial fibrillary acidic protein. Immune electron microscopy disclosed the presence of Ia reaction products in the Golgi apparatus, endoplasmic reticulum and plasma membrane of these cells with dendritic processes, indicating active synthesis of Ia molecules in microglia. In addition, Ia antigens were localized to the cells with ultrastructural features of macrophages. Thus, Ia-expressing cells in EAE seems to play dual roles: the induction of immunological reactions during earlier stages and the participation in reparative processes during convalescence.Supported by Grants-in-aid from the Ministry of Health and Welfare for Intractable Neuroimmunological Diseases and from the Ministry of Education, Science and Culture (Project 61570380 to HK) 相似文献
54.
Hochegger K Siebenhaar F Vielhauer V Heininger D Mayadas TN Mayer G Maurer M Rosenkranz AR 《European journal of immunology》2005,35(10):3074-3082
Recently, divergent reports on the role of mast cells (MC) in different glomerular diseases have brought our attention to their role in an accelerated model of anti-glomerular basement membrane (GBM) glomerulonephritis (GN). Genetically MC-deficient Kit(W)/Kit(W-v) mice, MC-reconstituted Kit(W)/Kit(W-v) mice and Kit+/+ control mice were subjected to anti-GBM GN. Kit(+/+) mice developed moderate proteinuria and glomerular damage following the induction of anti-GBM nephritis. In contrast, proteinuria and glomerular damage were dramatically increased in MC-deficient Kit(W)/Kit(W-v) mice. MC-reconstituted Kit(W)/Kit(W-v) mice showed proteinuria and glomerular damage comparable to Kit+/+ mice. A significant increase in infiltrating T cells and macrophages was detected in MC-deficient Kit(W)/Kit(W-v) mice as compared to Kit+/+ control mice and MC-reconstituted Kit(W)/Kit(W-v) mice. Accordingly, we observed an increase of TGF-beta1 mRNA in kidneys from Kit(W)/Kit(W-v) mice. Interestingly, we did not detect MC in the kidney using either Giemsa staining or RT-real-time PCR, but MC were found in the regional lymph nodes. Finally, mortality of Kit(W)/Kit(W-v) mice was significantly increased after the induction of anti-GBM GN due to uremia. Our report provides the first direct evidence that MC are protective in anti-GBM GN, possibly by modulating the influx of effector T cells and macrophages to inflammatory sites in the kidney. 相似文献
55.
用于杀虫剂评价的水池中无脊椎动物的群落结构及其种群动态 总被引:3,自引:0,他引:3
实验水池是评价杀虫剂效应和安全生的重要场所,水池中无脊椎动物群落结构和种群动态是评价杀虫剂的基础资料和考核指标,本文报告1992年至1993年在美国佛罗里达中部地区对应用于杀虫剂评价的实验水池中昆虫与其它无脊椎动物群落结构及其优势种的种群动态研究结果,用羽化诱捕、勺舀、网拉及挖取底物法,从实验水池中共采到昆虫与其它无脊椎动物50余类,其中,羽化诱捕到的昆虫中摇蚊占93.9%,蜉蝣目昆虫占4.6%, 相似文献
56.
Abdolamir Allameh Nargess Maleklou Mehryar Zargari Mohammad Hossein Sanati 《Neuroscience letters》2008
Recently we reported that antioxidant system in brain and spinal cord in experimental autoimmune encephalomyelitis (EAE) mice is mainly affected at early stages of the disease [M. Zargari, A. Allameh, M.H. Sanati, T. Tiraihi, S.H. Lavasani, O. Emadyan, Relationship between the clinical scoring and demyelination in central nervous system with total antioxidant capacity of plasma during experimental autoimmune encephalomyelitis development in mice, Neurosci. Lett. 412 (2007), 24–28]. The aim of the present study was to investigate the role of uric acid (UA) on antioxidant system in liver and plasma of EAE mice. EAE was induced in C57/BL6 mice (n = 60), followed by i.p. administration of UA (10 mg/kg BW) in 30 mice at three distinct clinical stages (A: prior to onset, B: after onset, C: after development of EAE). Livers were removed and processed for measurement of lipid peroxidation products, reduced glutathione (GSH), and glutathione S-transferase (GST) and total antioxidant capacity of plasma (FRAP). The results showed that lipid peroxidation products in liver of EAE mice was increased significantly (∼85%) as compared to normal. UA administration to EAE mice caused a significant suppression of liver lipid peroxidation products (∼45%) at early stages (A and B). There was an inverse relationship between lipid peroxidation and cellular GSH in liver. GSH was significantly depleted in mice liver during the EAE progression, but it was recovered (∼29%) when UA was injected before the onset of the disease (groups A and B). Plasma total antioxidant capacity was significantly decreased during the development of EAE, however it was subsided in mice treated with UA as compared to the corresponding controls (21%) in groups A and B. Elevated liver GST as a result of EAE induction was reversed in mice treated with UA particularly in groups A and B. These results indicate that hepatic glutathione system, particularly GST plays a major role in modulation of oxidative damages to central nervous system (CNS) during EAE induction. The positive response of antioxidant system to UA administration in EAE mice was corroborated with improvement of clinical manifestation of the animals. 相似文献
57.
Teodoro WR Velosa AP Witzel SS Garippo AL Farhat C Parra ER Sonohara S Capelozzi VL Yoshinari NH 《Pathology, research and practice》2004,200(10):681-691
The pathogenesis of diffuse connective tissue diseases (DCTD) is still unknown and has been extensively studied regarding its autoimmunity aspects related to extracellular matrix (ECM) remodelling, with an emphasis on the collagens at the inflammatory site. The present paper describes the pulmonary architectural and repair/remodelling responses to injury after immunization of rabbits with human type V collagen. The animal model consisted of rabbits immunized with collagen mixed with Freund's adjuvant and sacrificed 7, 15, 30, 75, and 120 days after the first of four doses of antigen. Pulmonary architecture remodelling response was evaluated by histology, morphometry, and the immunofluorescence method, according to compartments of reference (parenchyma and interstitium) and injury: 1 inflammation (polymorphonuclear and mononuclear cells); 2-repair (fibrosis) and 3-ECM remodelling (collagen system). The results showed an intense inflammatory involvement of the pulmonary vascular and bronchiolar parenchyma, characterized by increased wall thickness in small arteries, infiltrations by pseudoeosinophils, and mononuclear cells. Progressive remodelling of the pulmonary ECM was characterized by collagen deposition in the septal and bronchovascular interstitium, especially in rabbits sacrifices at 75 and 120 days. The ECM remodelling process was not reproduced when rabbits were inoculated with collagen types I and III. We conclude that the model reproduces morphologic changes similar to those observed in many DCTD, encouraging realization of other experiments to gain a better understanding of the pathogenesis of these diseases. 相似文献
58.
Gy. Kovacs 《Cancer Genetics and Cytogenetics》1981,3(2):125-129
The cytogenetic findings by G- and C-banding in a primary breast carcinoma are reported. The tumor is characterized by a high modal number of chromosomes (79) and 14 markers of ten different origins. Chromosome #1 is more frequently involved in structural and numerical aberrations than is any other chromosome; nine copies of 1q were present in each cell examined. This observation supports the hypothesis that duplication of chromosome 1q may play an important role in the progression of malignant tumors. 相似文献
59.
缺血性脑血管疾病是一个非常复杂的病理生理过程 ,是多种机制共同作用的结果。本文从针刺对实验性脑缺血在脑组织形态学改变、血液流变学、脑微循环等方面的研究进展作一综述。 相似文献
60.
Refractoriness to Gal N toxicity occurs especially in fetal rats, newborn rats, and in rats after partial hepatectomy. An injury however (laparotomy, incision on the back or ip BaSO4 suspension), prior to Gal N administration, also inhibits Gal N toxicity. In all these circumstances high levels of rat α2-macrofetoprotein (αMFP) occur. This protein is an acute phase reactant and is identical to rat α2-macroglobulin. αMFP isolated from the serum of injured rats and then administered to normal rats strongly inhibits Gal N toxicity. When time interval between the preceding injury, provoking αMFP production and Gal N administration shortens, the inhibiting effects are less and αMFP production remains low.During resistance to Gal N, the primary and secondary biochemical lesions of Gal N persist and the protecting effect of αMFP must be due to another mechanism, operating in later phases of cell injury. Very probably this is attributable to the stabilizing effect on membranes of hepatocytic organelles and the plasma membranes. As αMFP is an acute phase reactant the importance of these proteins to the course of hepatitis must be considered. 相似文献