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51.
Unfractionated cytokines have been shown to induce in vitro proliferation of neonatal rat Schwann cells but the nature of the mitogen(s) is not known. A mixture of rabbit antibodies specific for recombinant interleukin-1α (IL-1α) and interleukin-1β (IL-1β) inhibited Schwann cell proliferation induced by unfractionated human cytokines whereas antibodies to interleukin-2 (IL-2) and control IgG did not. However, purified human IL-1 and recombinant human IL-1α or β did not induce Schwann cell proliferation on their own. 相似文献
52.
目的总结胸腺切除术治疗老年及老年前期重症肌无力的临床效果。方法对1981年~2001年在我院行胸腺切除治疗的23例老年及老年前期重症肌无力患者的手术疗效进行回顾分析。结果在所有重症肌无力患者中老年及老年前期患者所占比例小,男性为多见;全身型为主,合并胸腺瘤及危象者多;手术总有效率43.5%。结论老年及老年前期重症肌无力的手术疗效较青壮年为差,但仍是可选择的一种重要方法。 相似文献
53.
This report describes a model for identifying sets of teaching abilities considered to be effective for medical school teaching staff, based on roles teachers assume and functions they are expected to perform as instructors. The specification of these teaching abilities was the first step in the development of a comprehensive course on Medical Instruction at the Basic Institute of Medical and Agricultural Biology of the State University of Sao Paulo, Botucatu, Brazil, where the senior author is employed. The work was based on the assumption that medical school teachers are expected to assume a variety of teaching roles and that identification and specification of the abilities that define their roles can result in more effective and efficient teaching. 相似文献
54.
二肽基肽酶Ⅳ抑制剂P32/98 总被引:1,自引:0,他引:1
王林 《国际药学研究杂志》2002,29(3):173-174
二肽基肽酶Ⅳ(DPPⅣ)涉及2型糖尿病病理过程中的信号传导过程,其抑制剂能够增强胰岛素样多肽(GIP)和胰高血糖素样肽片段(GLP)的活性,并能提高葡萄糖耐受水平.动物实验研究表明,糖尿病模型大鼠口服DPPⅣ抑制剂P32/98,能降低DPPⅣ的活性,改善糖耐受性以及增加胰岛素的敏感性.临床试验进一步揭示,P32/98的安全性和耐受性良好,能明显改善受试者糖耐受性和胰岛素应答水平. 相似文献
55.
The distribution in renal tumours of 3-fucosyl-N-acetyl lactosamine has been studied by using the monoclonal antibodies AGF 4.36 and AGF 4.48 and immunoperoxidase methods on tissue sections. Seven of 19 nephroblastomas and 12 of 30 renal cell carcinomas contained the epitope. In nephroblastomas the epitope was found on the terminals of type B tubules in six cases and in one case on the type A or neoplastic tubules. In renal carcinoma the antigen was found on the surface of tumour cells. The results suggest that in kidneys bearing nephroblastomas ureteric bud elements may grow into the tumour from the adjacent kidney. 相似文献
56.
目的 探讨种植受体血管内皮细胞在抗异种血管移植超急排斥反应 (HAR)方面的意义。方法 选用豚鼠→大鼠移植模型 ,先将分离、培养的大鼠动脉内皮细胞种植于去内皮的豚鼠动脉内壁 ,再将此豚鼠动脉植入大鼠体内 ,观察动脉血栓形成时间 ,并采用免疫组化技术检测了 Ig M、C3在移植后豚鼠动脉壁上沉积的情况。结果 已种植大鼠内皮细胞的豚鼠动脉血栓形成时间 (2 0 .3± 4.42 h)较植入大鼠体内的正常豚鼠动脉 (0 .35± 0 .2 84h)以及单纯去内皮豚鼠动脉血栓形成时间 (0 .16 5± 0 .0 77h)显著延长 (P<0 .0 0 1)。免疫组化结果显示 ,植入大鼠体内的正常豚鼠内皮细胞表面有 Ig M和 C3沉积 ,而预先种植大鼠内皮细胞的豚鼠动脉内壁无 Ig M和 C3沉积。结论 在异种供体血管壁上预先种植受者血管内皮细胞 ,可延长移植的异种供体血管通畅时间 ,该技术可能在抗异种血管移植 HAR方面具有重要意义 相似文献
57.
'Gliosarcomas' have long been considered to be mixed gliomas and sarcomas. The present study failed to define criteria which clearly delineate 'gliosarcomas' from glioblastoma multiforme and suggests that 'gliosarcomas' should be considered as spindle cell glioblastomas. A total of six cases originally diagnosed as 'gliosarcomas' were compared with four cases of glioblastoma multiforme. No clinical or prognostic features were defined which would clearly separate 'gliosarcomas' from glioblastoma multiforme. Macroscopically, biopsies from 'gliosarcomas' ranged from firm, apparently well-circumscribed tumours to poorly circumscribed lesions with a soft consistency resembling glioblastoma multiforme. Histology revealed a continuous spectrum in which 'gliosarcomas' with large reticulin-rich areas of spindle cells merged with typical glioblastomas containing only small islands of spindle cells and reticulin staining. Immunocytochemistry for glial fibrillary acidic protein (GFAP); S100 protein and alpha-smooth muscle actin (ASMA) showed that the majority of cells in reticulin-poor areas of 'gliosarcoma' and glioblastomas expressed S100 protein and GFAP; many expressed ASMA and some expressed both GFAP and ASMA. Spindle cells in reticulin-rich areas of 'gliosarcomas' and glioblastomas most frequently expressed ASMA but many cells also expressed S100 protein and GFAP; some cells expressed both GFAP and ASMA. The results of this study and a review of the literature suggests that there is a clinical, radiological and pathological continuum with glioblastoma and 'gliosarcoma' at different ends of the spectrum. It is suggested, therefore, that most, if not all, 'gliosarcomas' be redesignated as spindle cell glioblastomas and not be considered as a mixture of glioma and sarcoma. 相似文献
58.
Xiaoguang Chen Yi Li Lei Wang Mark Katakowski Lijie Zhang Jieli Chen Yongxian Xu Subhash C. Gautam Michael Chopp 《Neuropathology》2002,22(4):275-279
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain. 相似文献
59.
KENICHI TATSUMI TSUNEATSU MORI ETSUKO MORI HIDEHARU KANZAKI TAKAHIDE MORI 《American journal of reproductive immunology (New York, N.Y. : 1989)》1987,13(3):87-92
ABSTRACT: The culture supernatant of the TTK-1 cell line, established from human decidual tissue, was found to contain a factor that strongly suppressed the mixed lymphocyte reaction (MLR). The mechanism of the MLR-suppressive activity as well as the biochemical characterization of this factor was analyzed. The TTK-1 supernatant suppressed the MLR much more strongly than the culture supernatants of the three other malignant cell lines examined. The molecular weight of this factor was estimated to be between 43 kilodaltons (kd) and 67 kd by gel filtration chromatography. The TTK-1 supernatant also suppressed the proliferation of the interleukin 2 (IL-2)-dependent T cell lines, but did not suppress that of the IL-2-independent T cell lines, suggesting that the TTK-1 supernatant inhibited the action of IL-2 and subsequently suppressed the MLR. The fact that the TTK-1 cell line originated from human decidual tissue might imply the important role of this factor in immunological fetomaternal balance. 相似文献
60.
二乙酰二脱水卫矛醇对小鼠白血病L1210细胞增殖的影响 总被引:5,自引:0,他引:5
目的 研究二乙酰二脱水卫矛醇 (1 ,2 :5 ,6 dianhydro 3 ,4 diacetylgalactitol,DADAG)的抗脑白血病作用及机制。方法 用小鼠脑内移植瘤模型、MTT法、DNA掺入法、流式细胞仪和Westernblot法 ,观察DADAG对小鼠脑内移植瘤和体外白血病L1 2 1 0 细胞的作用 ,并探讨作用机制。结果 DADAG对DBA/ 2小鼠脑内移植白血病L1 2 1 0 有明显的抑制作用 ;对体外白血病L1 2 1 0 细胞同样有很强的抗增殖作用 ,其IC50 值为 2 4 6mg·L- 1 。DADAG不可逆地抑制L1 2 1 0 细胞内DNA的生物合成。DADAG 2 4mg·L- 1 处理L1 2 1 0 细胞 6h后 ,细胞发生G2 /M周期阻滞 ,2 4h后达最高峰。细胞周期素B1 蛋白水平在DADAG处理 2 4h后开始下降 ,而磷酸化的细胞周期依赖性激酶CDK1在DADAG处理 6h后开始上调 ,并呈时间依赖性。结论 DADAG的抗脑白血病作用与其抑制白血病细胞的增殖密切相关 相似文献