共查询到20条相似文献,搜索用时 15 毫秒
1.
1997年Asahara等在人外周血中发现内皮祖细胞(endothelial progenitorcell.EPC),随后有文献报道,从骨髓中分离出EPC.异体骨髓移植研究显示成体外周血EPC来源于骨髓。许多作者报告EPC参与生理性和病理性血管新生.具有潜在的临床应用前景。目前关于EPC的不少基本生物学问题尚不完全清楚,其生理和病理意义也有争议。 相似文献
2.
3.
人骨髓CD34^+造血细胞体外扩增形成HPP—CFC造血祖细胞的能力 总被引:1,自引:0,他引:1
目的和方法:高增殖潜能集落形成细胞(HPPCFC)是表达CD34+DRLin-的最早期造血祖细胞之一,它在体外的增殖分化能力可反映造血干细胞的某些特征。结果:本文研究了人正常骨髓CD34+造血细胞在体外扩增和形成HPPCFC的能力。利用CIMS100免疫磁性分离术首先获得>90%的CD34+造血细胞以富集HPPCFC。在含有Epo+GMCSF+IL3+IL6+SCF(简EGIIS)的无基质液培条件下,CD34+造血细胞在四周内可持续产生单个核细胞和HPPCFC,并使其总量最高可达1770倍和8倍,以第2和3周为最佳时期,但不同个体CD34+造血细胞的这种能力差别较大。结论:高度纯化的人骨髓CD34+造血细胞能够在含有最佳组合造血生长因子的无基质液培条件下持续扩增,为临床应用提供了重要依据。 相似文献
4.
A double layer agar technique was used to investigate the proliferative state of granulocytic progenitor cells (Colony Forming Units in Culture; CFUc) in human peripheral blood and bone marrow. The sensitivity of the progenitor cells to the S-phase specific agent, hydroxyurea, was used as an index of the proportion of cells engaged in DNA synthesis. In the presence of low concentrations of colony stimulating factor (CSF) the CFUc were found to be virtually insensitive to the drug. However, when cultured in the presence of increasing concentrations of CSF the proportion of CFUc apparently killed by hydroxyurea increased to a maximum of 23% for those cells in the blood and 39% for those in the marrow. The results indicate that CFUc which are slowly proliferating are sensitive to low concentrations of CSF. In contrast, those CFUc which are proliferating more rapidly require high concentrations of CSF before they will form colonies in culture. A model has been devised which suggests that as CFUc mature, their cell cycle time shortens and their sensitivity to CSF decreases. 相似文献
5.
6.
目的观察小鼠心肌梗死后骨髓造血干细胞在心脏内的分化及细胞因子的影响。方法C57/BL6小鼠60只分为骨髓动员组和对照组,先后行脾切除、骨髓移植(骨髓供体为增强绿色荧光蛋白转基因小鼠)、骨髓动员及建立心肌梗死模型。心肌梗死后3周将小鼠心脏取出并切片行组织学及激光共聚焦显微镜免疫荧光检查。结果骨髓动员可以增加EGFP阳性细胞在心脏中梗死区和边缘区的定植,但绝大多数EGFP阳性细胞都同时表达CD45。仅发现有极少数骨髓来源的心肌细胞、成纤维细胞及血管内皮细胞,且与骨髓动员无相关性。结论骨髓动员能够明显促进骨髓来源细胞定植入小鼠心脏的梗死区;极少数骨髓造血干细胞可以分化为心肌细胞,其数量远不足以修复梗死心肌及改善心功能;骨髓造血干细胞不参与梗死区疤痕形成的病理过程。 相似文献
7.
本实验用液体静置法体外培养小鼠骨髓基质细胞。用细胞化学法观察处于不同分化阶段基质细胞中的尿嘧啶核苷二磷酸半乳糖--4-表异构酶(Uridinediphosphogalactose-4-epimerase,UDPGal,EC5.1.3.a)活性。结果在各类骨髓基质细胞中均可见到很强的酶反应。在由原始网状细胞向成熟星状细胞分化过程中,酶活性逐渐增强。随着培养时间和延长(培养5、7、10天),星状细胞和成纤维细胞中酶反应的阳性率和阳性度逐渐增高。这证明在体外培养骨髓基质细胞中由UDPGal催化的代谢非常活跃 相似文献
8.
骨髓基质细胞与交联明胶-聚羟基丁酸酯膜的生物相容性研究 总被引:2,自引:0,他引:2
目的研究生物材料交联明胶-聚羟基丁酸酯膜与骨髓基质细胞的生物相容性,探讨新型材料在骨组织工程中的应用前景。方法体外培养兔骨髓基质细胞,分别接种于G-PHB(交联明胶-聚羟基丁酸酯)、PHB(聚羟基丁酸酯)和G(交联明胶)材料膜片。采用MTT法检测细胞增殖活性,体视学方法检测细胞粘附能力,荧光双染法检测细胞完整性,扫描电镜观察细胞-材料界面。结果MTT检测发现G-PHB组增殖活性最强,而且表现为最佳的细胞粘附特性,与对照组比较差异有显著性意义。各组细胞完整性分析没有发现显著性差异。扫描电镜观察显示,G-PHB组细胞粘附及铺展良好,优于其他各组。结论交联后的生物降解膜材料G-PHB与BMSCs细胞的体外相容性明显优于单纯膜材料PHB和明胶,在骨组织工程学领域具有良好的研究价值和应用潜力。 相似文献
9.
多发性骨髓瘤的骨髓细胞置于Dexter长期培养体系中,浆细胞可以长期生长。非贴壁层细胞形成CFU-GM的能力达6周以上,但随着培养时间的延长,CFU-GM的形成活性明显下降。浆细胞产生兔疫球蛋白单克隆特异性在Dexter长期培养体系中仍维持不变,但Ki-67阳性的浆细胞随着培养时间的延长而减少,以上结果说明浆细胞虽然可以在Dexter培养体系中生长并保持单克隆特异性,但此种培养体系不是浆细胞最佳的生长条件。本研究还表明Dexter长期培养不宜作为骨髓净化的手段用于多发性骨髓瘤的自体骨髓移植。 相似文献
10.
P. K. Lala 《Cell proliferation》1972,5(1):79-85
DNA-synthesis (S) times of myelocytes and nucleated erythroid cells in the bone marrow of healthy mice as well as mice bearing advanced Ehrlich ascites tumors were measured with the aid of a combined in vivo-in vitro double isotope labeling technique. Neither the S-period nor the rate of proliferation of these cells were influenced by the presence of the tumor in these hosts. This finding discounts the possibility that the marked retardation of DNA-synthesis and proliferation rate observed in the tumor cells themselves with advancing tumor-age is a nonspecific effect of the nutritional deterioration in the host. 相似文献
11.
Both murine and human bone marrow cells were cultured in plasma clots which were formed inside diffusion chambers implanted into cyclophosphamide- and saline-treated mice. After an initial fall, the number of mouse bone marrow cells and numbers of mouse myeloid stem cells (CFU-C) and agar cluster-forming units rose faster in the cyclophosphamide-treated animals. These hosts also favored formation of myeloid (CFU-D-G) and erythroid (CFU-D-E) colonies and myeloid clusters in the plasma clot. The number and growth rate of mouse CFU-D-G were higher than those of CFU-C from the same marrow population. These observations suggest the existence of humoral factors stimulating granulocyte progenitor cell replication and differentiation. At its best the increment of CFU-D-E number was equivalent to that caused by a single 0·1 unit erythropoietin dose. Culture of normal human marrow cells resulted in colonies in the plasma clot containing only granulocytes and macrophages. Cyclophosphamide-treated host animals were essential for human CFU-D-G development. Plating efficiency for human marrow myeloid colonies was better in the conventional in vitro agar cultures than in diffusion chambers. 相似文献
12.
射线诱导在体造血细胞凋亡的量时效关系的研究 总被引:1,自引:0,他引:1
以4—10Gy射线在体损伤的小鼠为模型,应用DNA电泳和流式细胞术等方法证实细胞凋亡是射线损伤在体骨髓造血细胞的途径之一,发现射线诱导的造血细胞凋亡有明显的量效和时效关系。4、6、8和10Gy照射后,细胞凋亡发生率均表现为升高-降低过程,各剂量诱导的凋亡发生率峰值分别出现在照后12、8、4和4h,6和8Gy诱导的凋亡发生率已达最高水平,约为30%,10Gy诱导的凋亡反而要低。上述结果表明,诱导细胞凋亡是射线损伤骨髓造血细胞的一个重要途径,而且凋亡的发生率受照射剂量和照后时间的影响。因此,深入研究射线诱导的细胞凋亡,将有助于揭示射线损伤造血功能的机理。 相似文献
13.
The survival of mouse bone marrow after freezing and thawing was assessed using two methods: the spleen-colony technique; and a cell-culture method. The results of these experiments indicate that both methods yield similar estimates of marrow cell viability. It is suggested that the cell-culture method be used as an assay of marrow-cell viability in situations where the spleen-colony technique is not applicable. 相似文献
14.
目的检测P27kip1与EGFR在星形胶质瘤中的表达,探讨其对增殖活性的影响,为治疗提供一定的依据.方法采用免疫组化S-P法检测星形胶质瘤EGFR、P27kip1的表达,每一例肿瘤用ki-67LI表示其增殖活性,应用SAS8.0统计软件进行结果分析.结果 1.P27kip1表达水平与星形胶质瘤病理分级负相关(rs=-0.487,P<0.0001).2.对EGFR、P27kip1及Ki-67LI联合分析显示:P27kip1( )EGFR(-)组的ki-67LI(5.0%)明显低于P27kip1( )EGFR( )、P27kip1(-)EGFR( )、P27kip1(-)EGFR(-)组(10.4%、10.4%、10.8%)(P<0.05).结论 1.P27kip1在星形胶质瘤的发生、发展过程中可能起抑制作用.2.P27kip1、EGFR对星形胶质瘤增殖活性起相互拮抗的作用. 相似文献
15.
Following Colcemid administration, mitoses accumulate preferentially in the subendosteal region of the bone marrow of the mouse. This finding suggests that the most rapidly proliferating cells are localized to the subendosteal region, and complements previous radioautographic studies which have demonstrated a corresponding labelling gradient in the marrow. Quantitative estimates of cell cycle time by the stathmokinetic method were precluded by the presence of significant Colcemid induced interphase cell loss. Colcemid also affected cell differentiation in the marrow. Following Colcemid administration there was a fall in mature granulocytes in the marrow, and a concommitant rise in marrow megakaryocytes. 相似文献
16.
朱鹮分布与栖息地内农民的关系 总被引:7,自引:0,他引:7
1998到 2 0 0 0年间 ,我们在陕西省洋县应用样方法调查了朱 (Nipponianippon)活动区 (面积约10 0 0平方公里 )内所有正在使用的巢和部分往年的旧巢 ,以及主要夜宿地和觅食地 ,并将当地的地形、水系和居民区数字化 ,建立了地理信息系统数据库。通过对其空间位置的统计分析 ,发现朱显著倾向于在村庄附近栖息。朱的活动区与湿地的分布密切相关 ,而村庄都分布在湿地附近。朱与人类保持一定的预警距离 ,同时也对农民的日常活动表现出一定的适应性。我们分析了朱二十年来的繁殖成功率 ,发现它与巢址到农户的距离无关。而且 ,朱营巢的海拔逐年降低 ,其主要活动区正向人口更密的低海拔农村转移。因此 ,我们认为朱对以人类为主导的山村生态系统有良好的适应性。 相似文献
17.
本文对42例克汀病人进行了全面检查,结果表明:克汀病患者发育滞后,瞳距增大,性发育滞后,多数病人出现聋哑;锥体和锥体外系受损出现生理反射亢进,病理反射阳性征。眼外肌麻痹等体征,主要见于神经型;脑CT显示:颅内钙化率增高、脑沟池增宽、脑室扩大。神经系统损伤部位有较强的选择性,脑发育不良导致精神发育迟滞。严重的骨骼发育障碍,呈多关节畸形,如膝关节,呈X型或O型腿 相似文献
18.
The eosinophil reserve capacity of the post-mitotic granulocyte compartment in the bone marrow and the effective eosinopoiesis in three haematologically normal men have been quantified by means of kinetic parameters of [3H]thymidine flash-labelled peripheral blood eosinophils. From (a) the time of the appearance in the blood of labelled eosinophils after the tracer injection, (b) the inflow characteristics of the labelled eosinophils in the blood and (c) the magnitude of the eosinophil granulocyte pool in the venous blood, the effective eosinopoiesis (i.e. the eosinophil turnover) was calculated to range between 0.014 and 0.031 × 109 cells/kg body weight per day (mean 0.22 × 109 cell/kg per day). The post-mitotic eosinophil reserve capacity of the bone marrow ranged from 0.09 to 0.20 × 109 cells/kg body weight (mean 0.14 × 109 cells/kg). The large reserve pool and the high turnover rate may contribute to sudden rises of the peripheral blood oesinophil counts in some cases of eosinophilia. 相似文献
19.
叶绿体结构状态与光化学活性的关系 总被引:20,自引:0,他引:20
叶绿体被膜阻碍以Fecy为受体的电子传递,而对以DCIP为受体的电子传递无妨。被膜完整度越高则P/O值也越高。类囊体膜结构的完整度高,则电子传递速率和P/O值也比膜结构受到破损时高。类囊体膜结构的完整度对保持PS Ⅱ活性是必要的,随着完整度的降低,PS Ⅱ在电子传递中所占比重相应减少。 相似文献
20.
A double isotope DNA labelling method has been used to determine the duration of DNA synthesis (S) in bone marrow lymphoid cells classified by their nuclear diameters in smears. Incorporation of 3 H-thymidine was confined almost entirely to marrow lymphoid cells of 8·0-15·0 μm nuclear diameter (large lymphoid cells). After exposure to 3 H-thymidine in vivo and 14 C-thymidine 40-104 min later in vitro , the proportion of cells labelled with 3 H alone to those labelled with 14 C(±3 H) in radioautographic smears, plotted against time indicated the efflux from S per hour. Collectively, 28·3 ± 1·1% of all large lymphoid cells were in S and the efflux from S was 15·1% per hour. With decreasing cell size (nuclear diameter) the efflux fell progressively from 28·3% per hour (11·0 μm) to 9·2% per hour (8·0-8·9 μm) and the proportion of cells in S declined from 54·9 ± 2·3% to 14·8 ± 1·6%. Influx into S, measured in vitro by reversing the sequence of isotopes, closely resembled the corresponding efflux values in vivo relative to cell size. Most DNA synthesizing marrow large lymphoid cells belonged to a subgroup with deeply basophilic cytoplasm. The results demonstrate that basophilic large lymphoid cells in the marrow are actively proliferating and have a mean S phase duration of 6·6 hr. The largest marrow lymphoid cells (11·0 μm) proliferate most rapidly (S phase, 3·5 hr; maximum cell cycle time, 6·4 hr) while S duration is prolonged progressively to 10·9 hr for the smaller cells (8·0-8·9 μm). 相似文献