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951.
线粒体Ca^2+转运与细胞代谢调节   总被引:4,自引:0,他引:4  
线粒体具有一套完整的Ca^2+转运系统,包括两条摄取途径和三条释放途径。生理条件下,它们在细胞胞质与线粒体钙稳态维持以及细胞能量代谢中起重要作用,线粒体从胞质摄取的Ca^2+可激活某些Ca^2+敏感的呼吸酶和代谢过程。病理条件下,线粒体Ca^2+转运发生紊乱,通过线粒体通透性转换导致细胞坏死或凋亡。  相似文献   
952.
重建端粒酶活性延长人成纤维细胞寿命的研究   总被引:9,自引:1,他引:8  
汪铮  易静 《实验生物学报》2000,33(2):129-140
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953.
胸腺细胞在胸腺外凋亡的形态学证据   总被引:1,自引:0,他引:1  
In vitro thymus explants culture designed in this paper can mimic the thymic microenvironment as it were in vivo. Theoretically, thymus explants are cut off free from blood stream. So if some developing or developed thymocytes had the inclination to migrate into the periphery, they would only be accumulated in the blood vessels within thymus explants. After 3-day's culture, under transmission electron microscope we observed the migrating thymocytes accumulated in the blood vessels of C57BL/6 mice thymus explants, and these thymocytes were occurring apoptosis at different stage. To our knowledge, this findings offers the first morphological evidence that thymocytes do not necessarily die inside the thymus in situ, and that having acquired the death signals thymocytes can migrate into the blood stream and die quickly outside the thymus. But this is not to say that we deny the intrathymic death hypothesis. On the contrary, we found the number of thymocytes occurring in situ apoptosis on the surfaces of stromal cells is far more than that of migrating into the blood vessels. So, our proposal is that there are two sites for thymocytes apoptosis, some die inside the thymus and the others die outside the thymus.  相似文献   
954.
鼠白细胞介素12(mIL—12)在昆虫细胞中的表达   总被引:1,自引:0,他引:1  
Since human IL-12 is species-specific in its functions and elicits little biological responses from mouse lymphocytes, it is necessary to express recombinant murine IL-12 for the usage in studying the effects of this cytokine in various rodent models. Thereby, we can investigate the role of IL-12 in immune response in vivo and evaluate its potential clinical utility. Thus, we firstly constructed two expression vectors, pVL1393-mp40 and pVL1393-mp35. They were used to co-transfect the insect cells(Sf9) separately with linearized polyhedrosis virus genomic DNA. Two kinds of recombinant viruses AcNPV-mp40 and AcNPV-mp35 were visually screened out, and mp40 and mp35 were co-expressed in the insect cells co-infected by AcNPV-mp40 and AcNPV-mp35. The results of real-time Biomolecular Interaction Analysis (BIA) and Northern blot demonstrated that the recombinant mIL-12 was expressed successfully in the insect cells. The molecular weights of recombinant mp40 and mp35 were 40 KDa and 22 KDa on SDS-PAGE under reducing conditions, respectively. The apparent molecular weight of recombinant mIL-12 is 80 KDa under non-reducing conditions of Western blot. Biological activity of the recombinant product was detected in conditional medium using antibody-capture bioassay. The expression level of recombinant mIL-12 was about 10-15 micrograms/10(6) cells, as compared with the calibration curve of mIL-12.  相似文献   
955.
天花粉收白诱发白血病细胞K562凋亡的研究   总被引:8,自引:1,他引:7  
Trichosanthin (TCS), an eukaryotic ribosome-inactivating protein isolated from the root tuber of Trichosanthes plant, has various biological activities including abortion induction, antitumor, and anti-HIV. In this study, cultured human leukemia K562 cells treated with trichosanthin were examined. Analysis of the cells by single laser flow cytometry showed the sub-G1 peak. DNA extracted from these cells formed a characteristic "ladder" on agarose gel electrophoresis. Under electromicroscope, typical morphological changes of apoptosis were also observed. From all of these findings, we concluded that trichosanthin was able to induce apoptosis in K562 cells.  相似文献   
956.
电融合方法建立抗结核杆菌单克隆抗体细胞株   总被引:1,自引:0,他引:1  
郭明霞 《微生物学报》1998,38(5):393-395
By using the electrofusion tecndque, the fusion of NSI myeloma cells with spleen cells of BALB / c mouse immunized with five species of mycobacteria was caaced cuL With the ophmal electrofUSion condihons, we obtained a high fuSion efficiency of l.75 hybrid cell clones per 105 spleen cells. ELISA was used for screening secrehng anhmycobacteria McAb hybrid cells. After cloning, 22 stable hybrid cells'lines were selected, and 8 of them had been studied.  相似文献   
957.
用酶标免疫检测法研究了根瘤菌4012a菌株细胞分裂素发酵的适宜培养基和培养条件。结果表明,其最佳培养基为(g/L):葡萄糖10.0,(NH4)2SO41.0,K2HPO4·3H2O0.6,MgSO4·7H2O0.1,CaCl2·2H2O0.4,FeCI3·6H2O0.04,Na2MoO4·2H2O0.1mg/L,泛酸钙100μg/L,腺漂吟200mg/L。该菌株在150r/min的旋转摇床上27℃振荡培养96h,发酵液中细胞分裂素产量可达908μg/L,生物活性(萝卜子叶扩大法)为1mg/L激动素当量。  相似文献   
958.
程控性细胞死亡(PCD)是细胞死亡的一种特殊形式。当细胞完成其功能使命,或遭受严重伤害,或发生异常时,由各种细胞内外信号分子激活细胞所固有的自杀程序而导致细胞死亡。PCD的调节控制是由于某种缺失所引起的,即细胞不能接受对细胞内在的自杀程序有抑制作用的...  相似文献   
959.
土壤水分胁迫加重,小麦旗叶、根系和籽粒中ABA含量迅速达到高峰,然后又快速降低;胁迫愈重,细胞分裂素(iPAs)峰值出现愈早,尔后下降,从而加速了植株衰老进程,导致产量降低。但在轻度水分胁迫上下上述性状与对照无显著差异。  相似文献   
960.
水分亏缺下细胞延伸生长与细胞膨压和细胞壁特性的关系   总被引:17,自引:1,他引:16  
在简要介绍植物细胞延伸生长的生物物理模型的基础上,综述了水分亏缺下植物细胞延伸生长与细胞膨压、细胞壁伸展性和细胞壁塑变阈值的关系,阐述了植物细胞壁调节在作物抗旱性中的作用。  相似文献   
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