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81.
82.
目的:体外分离培养人脐静脉内皮及内皮下间充质干细胞,观察采用不同的换液频度与细胞增殖和生长的关系。方法:实验于2006-03/11在辽宁医学院解剖学实验室完成。①选取正常健康产妇顺产或剖宫产的新生儿脐带,由辽宁医学院附属第一医院提供,产妇及其家属均知情同意。②根据更换细胞培养液时间的不同,分为接种后每24h,48h,72h更换培养液组。③无菌条件下将脐带用预热的磷酸盐缓冲液充分洗涤去血渍,从脐静脉一端插入留置针,用预热的磷酸盐缓冲液冲净静脉腔血,止血钳夹闭另一端,采用胶原酶消化法分离人脐静脉内皮及内皮下细胞,取消化30min的细胞悬液进行贴壁培养,以1×108L-1密度接种于24孔培养板中,每孔的细胞数和培养液量相同,按实验设计分组的时间方法更换培养液。④各组自培养24h开始,每天分别取各组细胞4孔,以噻唑蓝比色法测定生长曲线。并采用免疫细胞化学方法对分离的细胞进行表面抗原鉴定。结果:①间充质干细胞的形态学观察:原代培养1周,细胞以梭形细胞为主。传代培养2h细胞开始贴壁变形,24h基本完成贴壁,48h可见部分已贴壁的细胞开始分裂增殖,细胞形态多样,呈椭圆形、梭形、三角形等。5~7d贴壁细胞可见多核的成纤维细胞样。在细胞生长增生过程中,接种后每24h更换培养液组细胞增殖明显,生长状态均最好;接种后每48h更换培养液组次之;接种后每72h更换培养液组细胞增殖较慢,细胞生长状态也较差。②生长曲线:接种后每24h更换培养液组的细胞生长增殖较快,比接种后每48h及72h更换培养液组达到的同样细胞数平均提前2~3d(P<0.05);接种后每48h及72h更换培养液组之间差异无显著性意义(P>0.05)。③间充质干细胞表面抗原特性:免疫细胞化学分析显示CD166呈阳性,vWF呈阴性。结论:胶原酶消化法体外分离获得的人脐静脉内皮及内皮下细胞数量高、活性佳。更换培养液的频度不同,细胞的增殖生长过程和形态变化时间不同,接种后每24h更换培养液更有利于间充质干细胞的增殖生长和纯化。  相似文献   
83.
84.
中药复方治疗黄体功能不全致不孕症170例   总被引:8,自引:0,他引:8  
彭宝珍  顺惠芳 《医学争鸣》2005,26(22):2078-2078
0 引言黄体功能不全(LPD)是造成不孕的重要原因之一,约有10%~40%不孕症和反复流产与之有关[1]. 1993/2003我们在临床上以中药复方治疗LPD所致不孕症,疗效满意.  相似文献   
85.
吴惠芳  关福玉  罗毅 《药学学报》1997,32(5):377-383
建立了高效毛细管电泳系统分析法,分析体液样品中29种CNS药物,作为CNS药物中毒的快速的初筛方法。血、尿样品用有机溶剂萃取,胃液直接进样。用酸、弱碱和中性3组缓冲液体系进行电泳分离。以组分与电渗流迁移时间之比的相对迁移时间和紫外吸收光谱为定性指标。最低检测浓度0.5~5μg·mL-1。在此法基础上可增加分析品种。通用的提取方法可避免漏检,广谱分离条件便于分类,专一分离条件便于定性。本法用于实际中毒样品分析,证实所建方法操作简便、分析时间短、杂质干扰小。  相似文献   
86.
87.
OBJECTIVES: The main aim of this study was to reach consensus between students, faculty and general practice teachers on the educational objectives and requirements of the clerkship in general practice. METHOD: The consensus procedure consisted of four steps and all active general practice teachers (n = 116) were asked to participate in the study. RESULTS: We identified 189 educational objectives: 127 complaints (problems, symptoms, syndromes), 29 clinical skills and 37 objectives concerning the theoretical dimensions of general practice. Educational requirements crystallized to 16 essential preconditions of a teaching practice and 35 didactic activities to be performed by the general practice teachers. CONCLUSIONS: These consensus results will be used to structure the medical curriculum and as guidelines for the educational process during the clerkship.   相似文献   
88.
To study the cellular infiltrate that occurs within the airways of infants with respiratory syncytial virus bronchiolitis, samples of airways secretions were obtained by bronchial lavage from the lower respiratory tract of infants ventilated for this condition and from the upper airway of non-intubated infants with this disorder using nasopharyngeal aspirates. Cytospin samples were prepared so that differential cell counts could be performed on the cells obtained and alkaline phosphatase-antialkaline phosphatase immunocytochemical analysis of lymphocyte subsets was carried out using a panel of monoclonal antibodies, which included anti-CD3, anti-CD4, anti-CD8, anti-CD19, and anti-TcR gamma delta. Results from the lower and upper airways were similar. Large numbers of inflammatory cells were obtained, of which neutrophils accounted for a median of 93% in the upper airway and 76% in the lower airway. The numbers of CD8 positive cells detected were small and consistently less than CD4 positive cells, median CD4:CD8 ratios being 22.5:1 and 15:1 for the lower and upper airways. CD19 positive cells were rarely observed and no gamma delta positive lymphocytes were detected. These results indicate that neutrophils probably play a major part in causing symptoms in these infants. They do not support the concept that excessive lymphocyte mediated cytotoxic activity is principally responsible for the pathology in respiratory syncytial virus bronchiolitis.  相似文献   
89.
90.
Tsai  S; Patel  V; Beaumont  E; Lodish  HF; Nathan  DG; Sieff  CA 《Blood》1987,69(6):1587-1594
Using a novel coverslip-transfer culture technique, we recently demonstrated that primitive erythroid burst-forming units (BFU-E) can migrate, proliferate, and differentiate in intimate association with stromal fibroblastoid cells in the presence of serum proteins and erythropoietin. No other exogenous hemopoietic growth factors are required. Most of the colonies that develop in this system are very large erythroid bursts, and very few granulocyte-macrophage (GM) colonies are observed. In this report, we present data indicating that the predominance of erythroid burst colonies in this culture system is due to preferential binding of primitive erythroid progenitors to the stromal fibroblastoid cells and not to differential stimulation of these erythroid progenitors by these cells. We next show that the binding of BFU-E to stromal cells is blocked by anti-fibronectin antibodies. Finally, we demonstrate the preferential binding of BFU-E to fibronectin by using glass coverslips or Petri dishes coated with purified human plasma fibronectin. The binding is blocked by a monoclonal antibody specific for the cell-binding domain of fibronectin. We conclude that: primitive erythroid progenitors bind strongly whereas G and/or M progenitors (CFU-G/M) bind only weakly to fibronectin; primitive erythroid progenitors bind to the cell-binding domain on the fibronectin molecule; and erythroid progenitors and precursors remain bound to fibronectin throughout differentiation.  相似文献   
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