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71.
To better understand the pathophysiological role of Src protein, a non-receptor protein tyrosine kinase of 60kDa, in the ischemic brain, we investigated the time course and regional distribution of active Src expression by using a specific antibody against Tyr416 phosphorylated Src (phospho-Src) in the rat hippocampus after transient forebrain ischemia. In the hippocampus of the control animals, active Src expression was too low to be detected by immunolabeling. Beginning 4h after reperfusion, active Src expression became evident and, after 1 day, had increased preferentially in the CA field of the hippocampus proper and the dentate gyrus. By day 3, active Src expression markedly increased in the pyramidal cell layer of CA1 and the dentate hilar region in temporal correlation with neuronal cell death occurring in these areas, where cells typical of phagocytic microglia showed phospho-Src immunoreactivity. Double-labeling experiments revealed that cells expressing active Src were microglia that stained for biotinylated lectin derived from Griffonia simplicifolia (GSI-B4). Active Src expression began to decline at day 7 and returned to the basal level by day 14 after reperfusion. These results demonstrate increased phosphorylation of Src in activated microglia of the post-ischemic hippocampus, indicating that Src signaling may be involved in the microglial reaction to an ischemic insult.  相似文献   
72.
慢性乙肝患者杀伤性免疫细胞功能的研究   总被引:8,自引:0,他引:8  
范淳  刘林 《免疫学杂志》1996,12(1):43-47
通过对44例病毒性肝炎患者T细胞亚群,NK细胞活性与LAK细胞活性的观察,探讨了在慢性乙型肝炎病毒复制与非复制状态下的杀伤性细胞活性。结果表明:在乙肝病毒的高复制状态下,CD8^+细胞数增加,CD4^+/CD8^+比例显著下降;NK细胞活性与LAK细胞活性也明显低下,且在HBeAg与HBVDNA阳性组中,NK活性与LAK活性的改变与HBeAg的P/N值变化呈显著负相关,而NK活性与LAK活性变化则  相似文献   
73.
The formation of holes during the late stage of the isothermal crystallization in thin films of isotactic poly(propylene) between two cover glasses was observed by light microscopy and atomic force microscopy. This behavior can be described consistently by the well-known negative pressure effect. Light microscopy reveals the simultaneous and sudden occurrence of a large number of small holes at the liquid-solid interface after the liquid in front of the spherulites is completely confined by other spherulites for a certain time interval. In exceptional cases only a few holes appear and finally large cavities are formed. Atomic force microscopy measurements carried out in the height mode are able to prove the hole formation in front of the spherulites. Furthermore, a substantial thinning of the two-dimensional spherulites in thin films can be observed prior to the hole formation.  相似文献   
74.
This study was designed to test the hypothesis that cigarette smoke-induced inflammation and emphysema are amplified by the presence of latent adenoviral (Ad) infection, and to determine whether this emphysematous process can be reversed by all-trans-retinoic acid (RA) treatment. The results confirm that in guinea pigs, chronic cigarette-smoke exposure caused lesions similar to human centrilobular emphysema. They also show that latent Ad infection combined with cigarette-smoke exposure caused an excess increase in lung volume (P < 0.001), air-space volume (P < 0.001), and lung weight (P < 0.01), and further decrease in surface-to-volume ratio (P < 0.001) compared with smoke exposure alone. RA treatment failed to reverse these emphysematous changes. Analysis of inflammatory response in parenchymal and airway tissue showed that smoking caused an increase of polymorphonuclear leukocytes (PMNs) (P < 0.0002), macrophages (P < 0.001), and CD4 cells (P < 0.0009), and that latent Ad infection independently increased PMNs (P < 0.001), macrophages (P = 0.003), and CD8 cells (P < 0.001). We conclude that latent Ad infection amplifies the emphysematous lung destruction and increases the inflammatory response produced by cigarette-smoke exposure. In this study, the increase in CD4 was associated with cigarette smoke and the increase in CD8 cells with latent Ad infection.  相似文献   
75.
八珍汤对血虚模型小鼠造血调控因子影响的实验研究   总被引:7,自引:0,他引:7  
探讨八珍汤对由环磷酰胺引起的小鼠骨髓造血功能抑制的调控作用。采用环磷酰胺致小鼠血虚模型 ,测定八珍汤对骨髓抑制小鼠外周血象及其细胞因子产生的影响。结果表明 ,八珍汤对环磷酰胺所致血虚模型小鼠骨髓细胞有促进增殖作用 ;经八珍汤诱导制备的巨噬细胞、脾细胞、肺条件培养液和骨骼肌条件培养液能促进血虚模型小鼠骨髓细胞增殖 ,促进血虚模型小鼠骨髓基质细胞分泌肿瘤坏死因子 (TNF)。八珍汤对环磷酰胺所致化疗损伤的造血调控作用可能与直接或间接刺激造血微环境的基质细胞分泌正性和负性造血生长因子有关。  相似文献   
76.
Isometric and isokinetic torque curves at the knee joint   总被引:1,自引:0,他引:1  
Isometric and isokinetic torques of bilateral quadriceps and hamstrings were measured with Isokinetic Rehabilitation and Testing System (Model No. Cybex 340) on 40 normal untrained subjects, 20 males and 20 females, ranging between the ages of 23 and 35 years. The mean peak isometric and isokinetic torque values of both muscle groups showed no significant differences between dominant (right) and nondominant (left) limbs in both sexes; however there were significant differences between the male and the female. As the angular velocity increased, the peak torque significantly decreased, and the point of peak torque output occurred significantly later in the range of motion for quadriceps and hamstrings (p less than 0.01). There were no significant changes in the hamstrings to quadriceps (H/Q) ratios as the angular velocity increased. However, there were significant differences of mean H/Q ratio between male and female (p less than 0.01). Height had significant positive correlation with peak isometric and isokinetic torques for both quadriceps and hamstrings (p less than 0.01). Weight was found to correlate significantly with peak isometric and isokinetic torques (p less than 0.01). The mean isometric torques were significantly higher than the mean isokinetic torques for any joint angles in both sexes (p less than .01).  相似文献   
77.
We report on the antileukemia effect of interleukin 2 (IL2) on different immune cells from 22 patients with chronic myeloid leukemia (CML). Bone marrow cells from these patients were first cultured in modified long-term bone marrow culture medium for several days, then separately cultured with lymphokine activated killer cells (LAK), cytokine-induced killer cells (CIK), and dendritic cell cocultured CIK (DC-CIK) for another 1-2 days. They were then detected for presence of the Philadelphia chromosome (Ph) by cytogenetic analysis and fluorescence in situ hybridization (FISH). The percentage of Ph-chromosome-positive cells in the bone marrow mononuclear cells after culturing with CIK and DC-CIK was significantly lower than that after culturing with IL2 or LAK. Our results demonstrate that cytogenetics and FISH are useful techniques for the evaluation of the anti-CML effect of immune cells and that CIK or DC-CIK can be appropriate candidates for adoptive immune cell therapy in vivo or for leukemia cell purging ex vivo.  相似文献   
78.
79.
影像导航计算机辅助手术系统(ICAS)是一种为术者提供术野周围重要解剖结构信息的辅助工具,可提高手术安全性和成功率。合理的空间数据结构模型是确保ICAS实现导航功能的关键因素之一。本研究提出了组合邻接表线索化八叉树模型(MALTO),并就基本操作的可实现性和实时性,分析比较了MALTO与4种常用模型的性能。研究结果表明:MALTO不但可以实现数据查找、搜索和计算等基本操作,且具有时间效率优势。因此,MALTO是适合于ICAS的空间数据结构模型。  相似文献   
80.
凋亡肿瘤细胞负载的树突状细胞对抗原特异性CTL的激活   总被引:4,自引:0,他引:4  
为探讨凋亡Daudi细胞负载的树突状细胞 (DC )激发诱导肿瘤抗原特异性CTL及其生物学特性 ,采用常规方法从人外周血单个核细胞 (PBMC )诱导DC ,激发型CD40mAb联合 50Gyγ射线辐照诱导Daudi凋亡后负载DC ,然后与自体T细胞共育 ,并联合IL 2激发诱导肿瘤特异性CTL ;采用免疫荧光标记和流式细胞仪测定分析膜分子的表达 ;ELISA检测细胞因子的产生 ;Dextran FITC内吞实验分析DC的抗原摄取能力 ;3H掺入试验和51 Cr释放试验分别测定CTL的增殖和细胞毒效应。结果 :(1 )细胞因子序贯体外诱导 7d的DC ,对Dextran吞噬能力最强 ;(2 )CD40mAb诱导联合γ射线辐照 ,能有效介导Daudi细胞的凋亡 ;(3 )抗原负载联合CD40mAb激发可使DC上调表达CD1a、CD80、CD86和HLA DR ,并能促进IL 1 2的分泌 ;(4)凋亡Daudi负载后的DC在激发型CD40mAb作用下 ,能激发和扩增对Daudi细胞具有高效和特异杀伤作用的细胞毒性T细胞。因而认为凋亡肿瘤细胞负载联合CD40mAb刺激的DC可有效激活和扩增肿瘤特异性CTL。  相似文献   
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