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11.
观察7例慢性哮喘病人胸导管引流治疗前后外周血淋巴细胞内 cAMp/cGMP 值的变化。结果发现,慢性哮喘病人外周血淋巴细胞内 cAMP/cGMP 的值较正常人低(P<0.001);胸导管引流治疗后,哮喘病人外周血淋巴细胞内 cAMP/cGMP 值较治疗前升高(P<0.01)。提示,慢性哮喘病人外周血淋巴细胞功能异常、活性增强,这可能是哮喘发病的重要原因之一。胸导管引流引起的免疫抑制作用,一个重要的机理就是影响淋巴细胞内环核苷酸的代谢,而使淋巴细胞的活性降低,这可能也是胸导管引流治疗慢性哮喘的机理之一。 相似文献
12.
Masanobu Satake Manabu Inuzuka Katsuya Shigesada Tsuneyuki Oikawa Yoshiaki Ito 《Cancer science》1992,83(7):714-722
The core sequence of the enhancer of murine leukemia virus (MuLV) long terminal repeat is highly conserved in a large number of MuLV strains and appears to play an essential role when SL3-3 or Moloney strains induce T cell lymphoma in mice. We found by using the electrophoretic mobility shift assay that a polyomavirus enhancer core-binding protein, PEBP2, bound to this core motif of MuLV. We also noted that PEBP2 in several hematopoietic cell lines derived from B lymphocyte, macrophage and myelocyte lineages migrated significantly faster than the authentic PEBP2 detected in NIH3T3 (ibroblasts. Interestingly, PEBP2 detected in the cell lines of T lymphocyte lineage appeared to contain both types, which were indistinguishable in electrophoretic mobility from those of NIH3T3 and of B lymphocyte, macrophage and myelocyte lineages. The treatment of the nuclear extract containing PEBP2 with phosphatase generated PEBP3, which is a subcomponent of PEBP2 and retained the same DNA-binding specificity as PEBP2. The altered mobility of hematopoietic cell-derived or T lymphocyte-derived PEBP2 was found to be due to the alteration of the mobility of PEBP3. Based on the distinct mobility of PEBP2/3 of T lymphocytes from those of other hematopoietic cells, we discuss the implication of PEBP2 in MuLV-induced T cell leukemia and T cell-specific gene expression. 相似文献
13.
M. R. Angi F. Forattini M. Chilosi A. Cipriani G. De Caro G. Semenzato 《International ophthalmology》1990,14(1):1-11
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata. 相似文献
14.
A. V. Filatov S. A. Prokof'ev V. V. Shcherbukhin 《Bulletin of experimental biology and medicine》1992,114(5):1656-1659
Institute of Immunology, Ministry of Health of Russian. (Presented by Academician of the Russian Academy of Medical Sciences R. V. Petrov.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 11, pp. 506–508, November, 1992. 相似文献
15.
I. V. Smirnov A. A. Khachatur'yan 《Bulletin of experimental biology and medicine》1991,112(5):1601-1603
All-Union Hematology Research Center, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. I. Vorob'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 11, pp. 500–501, November, 1991. 相似文献
16.
脱细胞牛心包构建引导骨再生膜的初步研究 总被引:2,自引:1,他引:1
目的制备具有良好生物相容性和适宜降解吸收时间的引导骨组织再生(guided bone regeneration,GBR)膜材料。方法采用0.25%Trypsin+0.5%Triton X-100酶联脱细胞法对新鲜牛心包进行脱细胞处理,将脱细胞牛心包(A组)、甘油保存脱细胞牛心包(B组)、碳化二亚胺[1-ethyl-3-(3-dimethylamino propyl)carbodiimide hydrochloride,EDAC]交联脱细胞牛心包(C组)、甘油保存EDAC交联脱细胞牛心包(D组)4种膜材料分别植入38只SD大鼠背部皮下,不植人材料为E组。于2、4、8和16周分别处死大鼠7、12、12和7只,观察周围组织反应及材料的降解吸收情况。结果4种材料植入动物体内均有不同程度的炎性反应和纤维囊膜形成。术后4周,A组和C组的炎性反应轻微,纤维包膜变薄。A组膜材料吸收替代时间为8周左右,C组吸收替代时间为16周左右;16周时B组和D组材料仍有纤维包膜。结论EDAC交联脱细胞牛心包具有良好的生物相容性和理想的降解性能,在动物体内能顺利被自体组织替代。 相似文献
17.
18.
Emília P. Duarte Graça Baltazar Arsélio P. Carvalho 《The European journal of neuroscience》1994,6(7):1128-1135
We compared the effectiveness of Ca2+ entering by Na+/Ca2+ exchange with that of Ca2+ entering by channels produced by membrane depolarization with K+ in inducing catecholamine release from bovine adrenal chromaffin cells. The Ca2+ influx through the Na+/Ca2+ exchanger was promoted by reversing the normal inward gradient of Na+ by preincubating the cells with ouabain to increase the intracellular Na+ and then removing Na+ from the external medium. In this way we were able to increase the cytosolic free Ca2+ concentration ([Ca2+]c) by Na+/Ca2+ exchange to 325 ± 14 nM, which was similar to the rise in [Ca2+]c observed upon depolarization with 35 mM K+ of cells not treated with ouabain. After incubating the cells with ouabain, K+ depolarization raised the [Ca2+]c to 398 ± 31 nM, and the recovery of [Ca2+]c to resting levels was significantly slower. Reversal of the Na+ gradient caused an −6-fold increase in the release of noradrenaline or adrenaline, whereas K+ depolarization induced a 12-fold increase in noradrenaline release but only a 9-fold increase in adrenaline release. The ratio of noradrenaline to adrenaline release was 1.24 ± 0.23 upon reversal of the Na+/Ca2+ exchange, whereas it was 1.83 ± 0.19 for K+ depolarization. Reversal of the Na+/Ca2+ exchange appeared to be as efficient as membrane depolarization in inducing adrenaline release, in that the relation of [Ca2+]c to adrenaline release was the same in both cases. In contrast, we found that for the same average [Ca2+]c, the Ca2+ influx through voltage-gated channels was much more efficient than the Ca2+ entering through the Na+/Ca2+ exchanger in inducing noradrenaline release from chromaffin ceils. This greater effectiveness of membrane depolarization in stimulating noradrenaline release suggests that there is a pool of noradrenaline vesicles which is more accessible to Ca2+ entering through voltage-gated Ca2+ channels than to Ca2+ entering through the Na+/Ca2+ exchanger, whereas the adrenaline vesicles do not distinguish between the source of Ca2+. 相似文献
19.
20.
Effects of zymosan-activated plasma and phorbol myristate acetate on isolated, perfused rabbit lungs
The effects of complement activation on pulmonary vascular permeability are disputed. In rabbit lungs perfused with autologous blood, zymosan activated plasma (ZAP) induced a moderate increase in pulmonary vascular resistance (PVR), but did not detectably change the vascular permeability within 2 h. The stronger neutrophil granulocyte (PMN) activator, phorbol myristate acetate (PMA), usually gave larger PVR increases and also increased pulmonary vascular permeability. Lungs from neutropenic animals, similarly perfused and given PMA, showed unchanged PVR reactions but had no apparent increase in vascular permeability. Lungs perfused with cell-free medium and given PMA displayed modest PVR increases, and no measurable permeability change. The lung preparatory procedure itself markedly influenced leukocyte circulation. Exsanguination of lung donors decreased the concentration of circulating PMN significantly, and they virtually disappeared from the perfusate within minutes after start of lung perfusion. PMN-mediated effects must therefore have been caused by cells already sequestered in the lungs. We conclude that ZAP does not induce an increased pulmonary vascular permeability in isolated, perfused rabbit lungs, in contrast to PMA. The permeability effects of PMA appear to be PMN dependent. 相似文献