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61.
目的摸索人脐血间充质干细胞(mesenchymal stem cell,MSC)的培养条件。方法根据不同采血量、首次换液时间、胎龄、不同培养基对样本分组,比较不同培养条件对脐血中的间充质干细胞原代生长的影响,以流式细胞仪对培养出的间充质干细胞进行细胞表面标志检测。结果在相同条件下,取10ml的脐血能较大程度培养出间充质干细胞;观察首次换液时间在培养后96h较为合适,延长换液时间有利于数量不占优势的单核细胞充分贴壁:早产胎儿的脐血培养出的间充质干细胞成功率较高;胎牛血清的质和量决定了培养成功与否。培养出的间充质干细胞不表达造血细胞系的标志(CD34、CD45、CD14)及内皮细胞的标志(CD106),强表达CD29、CD44、CD13。结论样本量、首次换液时间、胎龄、培养基的质和量对MSCs的成活、生长有关键作用。  相似文献   
62.
Smooth muscle cells have been isolated from human umbilical cord veins, characterized and cultured for the development of an endothelialsmooth muscle cell co-culture system. After harvesting endothelial cells, the umbilical cords were trimmed of amnion, connective tissue and arteries, split into pieces, cut open longitudinally and placed with the luminal surface of the explant down onto a culture plate, without the use of proteolytic enzymes. Adherent primary cells were sequentially passaged and various cytological/biochemical characterizations were performed between passages 2 and 10. Cells stained positive for antibodies against smooth muscle actin, negative for antibodies against factor VIII and displayed typical hill and valley morphology when confluent. Cell proliferation was stimulated and supported in a concentration-dependent manner by both human serum and fetal bovine serum over the range 1%–20%. The use of human serum at concentrations >10% decreased the population doubling time during exponential growth by circa 50%. The cells were also characterized by high seeding efficiencies (>70%) and retained their diploid karyotype for up to 3 months in culture. Endothelial cells and smooth muscle cells prepared from umbilical veins were then seeded at varying densities onto either side of porous tissue culture inserts coated with fibronectin. Utilising the measurement of electrical resistance, the optimal seeding density of 5×104 cells/cm2 for each cell type gave maximal resistance across the cell bi-layer already after 24 hours, which remaining essentially unaltered for up to 4 days of culture and which was always substantially higher than the resistance of filters seeded only with endothelial cells on one side. This was not substantially affected either by increasing passage of the HUVSM cells cultured with a fixed passage of endothelial cells, or by varying the donor origin of the endothelial cells. In terms of functionality of the selective permeability of the model, the calcium ionophore ionomycin (25 M), added to the endothelial side of the bi-layer, caused a 30% reduction in the electrical resistance across the co-culture within 60 minutes, with control resistance being re-established within 1 hour of removal of the ionophore by washing. These results clearly indicate that smooth muscle cells and endothelial cells prepared from the same human blood vessel can be reconstituted into a functional vascular model suitable for the study of biochemical, physiological and toxicological phenomena in the human vascular wall.Abbreviations BCA bicinchoninic acid - BSA bovine serum albumin - DMEM DMEM medium supplemented with 4.5 g/l glucose, 100 IU/ml penicillin, 100 g/ml streptomycin and 1.25 g/ml fungizone - DMEM-1 DMEM supplemented with 20% FBS, 300 IU/ml penicillin, 300 g/ml streptomycin and 3.75 mg/ml fungizone - DMEM-2 DMEM supplemented with 20% FBS, 100 IU/ml of penicillin, 100 g/ml of streptomycin and 1.25 g/ml of fungizone - DMSO dimethyl sulfoxide - FBS fetal bovine serum - HPF human pulmonary fibroblasts - HS human serum - HUVE human umbilical vein endothelial - HUVSM human umbilical vein smooth muscle - M199 M199 medium supplemented with 20% HS, 100 IU/ml penicillin, 100 g/ml streptomycin, 1.25 g/ml fungizone and 2 mM L-glutamine - P passage number - PBS phosphate buffered saline - TCA trichloroacetic acid - vwF von Willebrand factor (factor VIII)  相似文献   
63.
目的:利用体外培养人脐静脉内皮细胞,观察中药红景天对细胞生长的影响,初步探讨急、慢性高原病患者服用中药红景天防治高原病及改善症状等的作用机制。方法:培养人脐静脉内皮细胞EVC-304,设对照组与加药组,加药组分别加入不同浓度的红景天,培养3d后计数。加药组及对照组细胞用瑞氏染料染色并拍照。收集细胞以流式细胞术检测细胞周期。结果:对照组细胞形态正常,成梭形,排列紧密,分散均匀。加药组细胞数量明显减少,细胞皱缩,聚集成团,形态各异。流式细胞术检测显示加药组G1期细胞含量增多,S期细胞减少。结论:红景天具有抑制血管内皮细胞生长的作用,可能是通过抑制细胞的增殖来抑制内皮细胞生长。抑制血管内皮细胞生长对于阻止血管内膜增生,防止形成肺动脉高压,降低慢性高原病发病率具有实际应用意义。  相似文献   
64.
Regulation of nuclear factor of activated T cells-c2 (NFATc2) gene expression is not clearly defined. We previously reported reduced NFATc2 protein expression in cord blood T lymphocytes. Here we show that NFATc2 expression in T cells is dependent in part on the presence of IFN-gamma during primary stimulation, as blocking of IFN-gamma blunted NFATc2 protein and mRNA upregulation. Conversely, addition of exogenous IFN-gamma during stimulation resulted in increased expression of NFATc2 in cord blood T lymphocytes. This correlated with rescue of deficient IFN-gamma expression by cord blood T cells. Rescue of IFN-gamma expression in cord blood T cells was dependent on the presence of antigen-presenting cells, as addition of IFN-gamma during stimulation of purified cord blood T cells did not result in an increase of IFN-gamma expression, and depletion of monocytes ablated the rescue of IFN-gamma expression. Our results point to impaired function in the antigen-presenting cell population of cord blood, playing a role in the hyporesponsiveness of T cells.  相似文献   
65.
Human umbilical cord blood, which in the past was discarded with the placental tissue, provides a convenient source of fetal hemopoietic cells for scientific analysis and clinical use. Cord blood cells are immature compared to analogous populations in adult peripheral blood. Cord blood B lymphocytes display unique phenotypic and functional characteristics. The antigens CD1C, CD38, CD5, and CD23, although normally expressed on only a small percentage of circulating B cells in adults, are highly expressed on cord blood B cells. Recent studies have demonstrated that whereas cord blood B cells are functionally naive, their potential is similar to that of adult B cells if optimal T-cell help is available. Thus, the failure of B-cell responses in cord blood is due to the T cells. The functional abnormalities of T cells from newborns can be summarized as a dominance of the effects of TH0 cells. Thus, the cytokines produced are immunosuppressive rather than mediating helper activity for B cells. NK activity in cord blood is also depressed compared to that in adults. Cord blood is a very rich source of hemopoietic progenitor cells. The spectrum of progenitors shows a predominance of early progenitor cells when compared with bone marrow. These cells provide an alternative source to adult bone marrow for stem cells to use for hemopoietic reconstitution and as targets in the treatment of hereditary deficiencies by gene therapy. These features make cord blood a unique research tool to investigate hemopoietic ontogeny and a unique clinical tool for transplantation.  相似文献   
66.
目的:研究表达载体介导的反义RNA对人巨噬细胞移动抑制因子(MIF)表达的抑制作用。 方法:用亚克隆技术构建可转录MIF反义RNA的真核表达载体pcDNA3-antiMIF。用lipofectamine2000分别将pcDNA3、pcDNA3-antiMIF转染可表达MIF的HEK293(293-MIF)细胞,用Real-time定量PCR鉴定MIF mRNA表达水平。将pcDNA3-antiMIF转化人脐静脉血管内皮细胞(HUVECs),建立可表达MIF反义RNA的HUVECs(HUVECs-antiMIF)细胞。将MIF的真核表达载体pSecTag-MIF转染HUVECs-antiMIF,用Real-time定量PCR鉴定MIF mRNA的表达水平。 结果:正确构建了MIF反义RNA的表达载体pcDNA3-antiMIF。MIF 反义RNA对293-MIF细胞中MIF表达的抑制水平达32%(P<0.05)。建立稳定表达MIF反义RNA的HUVECs-antiMIF细胞株。HUVECs-antiMIF中MIF的表达受到抑制,表达水平降低40%(P<0.05)。 结论:表达载体介导的反义RNA能有效地抑制MIF的表达,建立了稳定表达MIF反义RNA的HUVECs。  相似文献   
67.
The effect of reduced umbilical blood flow rate on fetal core temperature was investigated in five chronically instrumented fetal sheep (gestational age 124 days). On average, fetal-maternal temperature difference increased 0.13±0.02 °C when blood flow rate was decreased to about 1/3 of normal (248±69 ml min–1) for 30 min. The small temperature rise is the consequence of predominant heat dissipation through the placenta, and of diminished oxygen consumption.  相似文献   
68.
目的 分析胎龄<34周早产儿不同断脐方式下血红蛋白、胆红素及相关并发症差异,为早产分娩行挤压脐带断脐法(UCM)提供临床依据。方法 回顾性分析115例经阴道分娩的胎龄<34周的早产儿,根据断脐方式分为UCM组(n=59)和立即断脐(ICC)组(n=56),比较两组早产儿娩出后血红蛋白变化趋势和输血量、住院期间经皮胆红素值及光疗时间以及颅内出血、早产儿视网膜病变、支气管肺发育不良和坏死性小肠结肠炎的发生率。结果 UCM组出生后1 h内、出生后1周左右和出院前血红蛋白显著高于ICC组(t=2.246、2.123、1.886,P<0.05),住院期间ICC组早产儿输血次数及每人次输血量显著多于UCM组(χ2=2.145,t=2.160,P<0.05)。两组经皮胆红素达峰时间均为3~6 d,UCM组经皮胆红素值显著高于ICC组(t=2.231、2.654、2.686、2.038,P<0.05),两组光疗时长差异无统计学意义(P>0.05)。早产儿住院期间发生颅内出血、视网膜病变、支气管肺发育不良及坏死性小肠结肠炎等并发症两组间差异无统计学意义(P>0.05)。结论 与正常断脐相比,挤压脐带可增加胎龄<34周早产儿的血容量和血红蛋白量,减少住院期间输血次数及输血量,且不增加患儿病理性黄疸和并发症的风险,可作为胎龄<34周早产儿首选的断脐方法。  相似文献   
69.
针药并治椎动脉型颈椎病35例   总被引:2,自引:0,他引:2  
采纳用针药并治、配合牵引治疗椎动脉型颈椎病35例,结果治愈16例,好转18例,无效1例,总有效率97.1%。说明针刺配合强筋汤及牵引治疗椎动脉型颈椎病,起到协同的作用。提高了临床疗效。  相似文献   
70.
针灸治疗原发性痛经68例临床观察   总被引:6,自引:0,他引:6  
采用针刺配隔姜灸治疗原发性痛经 6 8例 ,总有效率 97.0 6 % ,与药物对照组相比 ,P<0 .0 1 ,说明针灸治疗组疗效明显优于药物对照组  相似文献   
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