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1.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。  相似文献   
2.
人癌干细胞集落形成测定常用双层琼脂平皿法。新法系采用园形玻璃毛细管法培养!可 以减少细胞用量及药物消耗。管内径为1.3mm,管长9.75cm,内盛15.000有核细胞/50μl,培养7~ 14天。50例肿瘤活检标本生长成功率为88%,并可供化疗药物敏感性试验用。这种微量化检测具有 独特的优点,便于推广应用。  相似文献   
3.
小檗胺对小鼠脾细胞毒性T淋巴细胞活性的抑制作用   总被引:2,自引:0,他引:2  
小檗胺对小鼠脾细胞毒性T淋巴细胞活性的抑制作用罗崇念,林新,王立为,赵扬,谢蜀生,肖培根(中国医学科学院药用植物研究所,北京100094;北京医科大学免疫学教研室,北京100083)小檗胺(berbamine)是小檗属植物中的一种双节基异喹啉类生物碱...  相似文献   
4.
在线考试系统设计   总被引:1,自引:0,他引:1  
作为评价网络学习效果的一个环节,网上考试越来越被人们接受和认同。文章介绍了在线考试系统的功能和结构,并对该考试系统中所用到的关键技术进行了详细的介绍,包括系统的通用性和安全性、题库的建设和管理、随机组卷算法等。  相似文献   
5.
在标记脐血造血祖细胞表面抗原(HPCA),CD34中,比较抗-HPCA-2-FITC和Tk3(纯抗体)标记的CD(34+)细胞在流式细胞仪分析中的荧光特征及两种单抗标记的CD(34+)细胞与体外培养的粒单细胞集落形成单位(CFU-GM),红系爆发形成单位(BFU-E),和混合集落形成单位(CFU-Mix)的相关性。结果发现脐血有核细胞中,抗HPCA-2阳性细胞占1.05±0.72%(n=13),Tk3阳性细胞占2.06±1.25%(n=8),差别显著(P<0.05)。每毫升脐血两种抗体标记的细胞分别为96.56±56.64和231.40±163.93(P<0.05)。尽管HPCA-2阳性细胞与Tk3阳性细胞数量呈显著正相关(r=0.875,P<0.01),前者与CFU-GM,BFUE,CFU-Mix及集落总数CFUs均呈正相关,而后者仅与CFU-GM,CFUs相关。研究提示在检测造血祖细胞时,用抗-HPCA-2-FITC代替Tk3可降低假阳性,获得较好的OD(34+)细胞与CFU间的线性关系。  相似文献   
6.
单独一种维生素缺乏对免疫功能的影响已有较多研究报道,但维生素缺乏一般不会单独发生,为此本实验研究了维生素A、E、B_2、B_6及叶酸供给不足(1/3生理需要量)、加倍补充(2倍和3倍生理需要量)后对小鼠抗体形成细胞的复合效应。动物喂养6周(不足纠正组喂8周),结果显示,不足组抗体形成细胞显著低于对照组,而2倍、3倍组则显著升高,不足组补充正常量维生素后,抗体形成细胞升高超过对照组,与2倍量组无显著差异;另外,该几种维生素对肝脏RNA、脾脏DNA、RNA及肝脏蛋白质均有明显影响,且抗体形成细胞的变化与核酸、蛋白质含量改变相平行,提示后者可能是维生素作用于体液免疫系统的生化机制。  相似文献   
7.
目的 通过对人胎盘CD133+细胞群中高增殖潜能集落形成细胞(HPP-CFC)检测与生物学特性的分析,证明人胎盘存在早期造血干/祖细胞(HSPC)。 方法 采用机械法制备人胎盘组织(PT)单细胞悬液,用Histopaque-1007分离出单个核细胞(MNC),经磁式分选(MACS)富集CD133+细胞,培养28 d后观察HPP-CFC集落形成能力,用流式细胞仪(FCM)对分选的细胞组份和HPP-CFC进行表型分析,实验全程用脐带血(UCB)作平行比较分析。 结果 培养28 d后,PT-CD133+与UCB-CD133+细胞组份分别扩增了266和362倍,前者低于后者(P<0.01);PT-CD133+与UCB-CD133+细胞中HPP-CFC分别为(32.4±11.2)/5×103、(17. 7±5.7)/5×103,前者形成的HPP-CFC数量明显高于后者(P<0.01);PT-CD133+、UCB-CD133+细胞培养至28 d时,除UCB-CD133+组的CD133+CD34-亚群比例无明显改变外,CD133+CD34+、CD133-CD34+和CD133+CD34-(PT-CD133+组)亚型均比培养前减少。 结论 人胎盘组织CD133+细胞中存在HPP-CFC,说明胎盘CD133+细胞群中存在早期HSPC。  相似文献   
8.
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis.  相似文献   
9.
The use of Percoll for isolation and subfractionation of PBMC and T-lymphocytes by discontinuous and continuous density gradient centrifugation is described: PBMC were isolated from human peripheral blood by discontinuous density gradient centrifugation on Percoll. The use of Percoll instead of Ficoll-Isopaque has the advantage that Percoll, in contrast to Ficoll-Isopaque, does not alter the density of monocytes. Therefore, a better separation of lymphocytes and monocytes was achieved after subsequent continuous density gradient centrifugation on Percoll. E-RFC were isolated by discontinuous density gradient centrifugation after a first low speed centrifugation step banding lymphocytes and SRBC on a Percoll-Ficoll cushion, and a subsequent high speed centrifugation step separating high density rosettes and SRBC from low density non-E-RFC. The advantage of this procedure is the short time of performance and that there is no need to resuspend the lymphocyte/SRBC pellet. PBMC, nph.PBMC T-lymphocytes were further subfractionated by continuous density gradient centrifugation on Percoll. The method described here resulted in a good separation of lymphocytes and monocytes. However, to obtain lymphocyte fractions with minute numbers of contaminating monocytes, a depletion of monocytes prior to further subfractionation of the lymphocytes by continuous density gradient centrifugation is recommended. A marker analysis of T-lymphocytes subfractionated by continuous density gradient centrifugation on Percoll shows that high density T-lymphocytes are enriched in ANAE positive lymphocytes of type 1 and depleted of ANAE positive lymphocytes of type 2. Low density T-lymphocytes are enriched in ANAE type 2 cells and depleted of ANAE type 1 cells. On the other hand, no considerable differences were found when analyzing the T-cells from different fractions for differentiation antigens by means of monoclonal antibodies (anti Lyt 3, OKT4, and OKT8). The results may indicate that subfractionation of T-lymphocytes by continuous density gradient centrifugation on Percoll provided T-cells in different functional states rather than T-cells of distinct subclasses.  相似文献   
10.
We have determined cutaneous DTH reactions to SK-SD and PPD and peripheral blood lymphocyte profiles in a group of asbestos workers in two consecutive surveys. It was found that asbestosis and, to a lesser extent, the presence of ANA are significantly correlated with the lack of response to the above antigens. 83% of asbestos workers when tested at a 4 year interval fell into the same two categories of responsiveness (lack of response or response at least to one antigen).The asbestosis cases had lower total lymphocyte count as well as proportions and absolute number of E-RFC as compared to asbestos workers without asbestosis and/or ANA. Furthermore, the latter group showed the lower percentages and absolute number of E-RFC than the matched controls. The presence of ANA is also correlated with lower proportions of E-RFC. However, this is related at least in part to asbestosis.  相似文献   
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