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The inhibitory effect of parvovirus H-1 on the colonyforming ability.in vitro of QGY-7703,a cultured human hepatoma cell line,and on the formation and growth of its tumors in nude mice was studied.With higher multiplicity of infection(MOI) of H-1 given,survival of the QGY-7703 cells was found to be decreased.H-1 DNA amplification level at 30h postinfection(p.i.) was detected to be 7.4 times higher than that at 2h by dispersed cells assay,while the cells were delayed to enter into S phase.Plaques were formed in the indicator cells(new-born human kidney cell line,NBK) by progeny H-1 virus particles released from the infected QGY-7703 cells by infectious cell center assay.The formation of tumors in nude mice by QGY-7703 cells which were injected s c at 2h postinfection was observed to by prevented in 2 proups with given MOI 25 and 50.The tumor growth of MOI 10 group occurred at a lower exponential rate than that of control,after a 20d latent period.It was evident that parvovirus H-1 exhibited a direct inhibitory effect on the formation and growth of human hepatoma cells in vivo as well as in vitro.  相似文献   

3.
Selective proliferation of human γδ T cells in vitro   总被引:1,自引:0,他引:1  
The effect of monoethylphosphate (MEP,commercial available or synthesized) together with IL-2 on the selective proliferation of human γδT cells in vitro from peripheral blood mononuclear cells (PBMC) of healthy donors and of cancer patients was investigated.The γδT cells were stimulated by MEP to proliferate in a dose-dependent manner.The effect of synthesized MEP was 10 times greater than that of commercial MEP.When the PBMCs of healthy donors were cultured for 25 d in the medium containing different concentrations of MEP,the total cell number increased about 1000-3000 fold;and the ratio of γδT cells reached to 70-80%.The selective expansion of γδT cells depended on the synergic action of MEP and IL-2.The bulk cultured γδT cells exhibited obvious cytotoxic activities against allogenic tumor cell lines (SQ-5,K562 and Daudi) and autologous tumor cells.The culture system described here not only offers a simple method for obtaining a large number of γδT cells which may become a new effector in the adoptive immunotherapy,but also provides a useful model for the further studies of the structure and function of γδT cells in vitro.  相似文献   

4.
To develop a rabbit corneal endothelial (RCE) cell line, in vitro culture of RCE cells was initiated from Oryctolagus curiculus corneas and a novel RCE cell line was established in this study. To initiate the primary culture of RCE cells, corneas from rabbit eyes were sliced and attached into glutin-coated wells with endothelial cell surface down. After being cultured at a time-gradient interval from 48 to 6 h, the corneal slices were detached and reattached into new wells, respectively. Cells in the wells containing only a pure population of RCE cells were collected and cultured in 20% FBS-DMEM/F12 medium con- taining chondroitin sulfate, ocular extract, epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), carboxymethyl-chitosan, N-acetylglucosamine hydrochloride, glucosamine hydrochloride, culture medium of rabbit corneal stromal cells and oxidation-degradation products of chondroitin sul- fate at 37℃, 5% CO2. The cultured RCE cells, in quadrangle and polygonal shapes, proliferated to con- fluence 3 weeks later. During the subsequent subculture, the shape of RCE cells changed gradually from polygonal to more fibroblastic. A novel RCE cell line, growing at a steady rate, with a population doubling time of 53.8 h, has been established and subcultured to passage 67. Chromosome analysis showed that the RCE cells exhibited chromosomal aneuploidy with the modal chromosome number of 44. The results of immuno-cytochemical staining with neuron specific enolase (NSE) confirmed that the RCE cells were in neuroectodermal origin. Combined with the results of vascular endothelial growth factor (VEGF) treatment and endothelial cell morphology recovery, it can be concluded that the cell line established here is an RCE cell line. This RCE cell line may serve as a useful tool in theoretical re- searches of mammalian corneal endothelial cells, and may also have potential application in artificial corneal endothelium development.  相似文献   

5.
Summary We have developed a serum-free system to culture postembryonic growth plate chondrocytes while maintaining some important phenotypic characteristics of their tissue of origin. This serum-free medium was as effective as medium containing 10% newborn bovine serum (NBS) for recovering the cells from enzymatic isolation. Surface secretory activity of chondrocytes cultured in monolayer, assessed through scanning electron microscopy, was also comparable to cells grown in medium containing serum. The effects of growth hormone (GH) and insulinlike growth factor-I (IGF-I) were also studied using the serum-free medium. GH had no effect on cell density and morphology of the cells compared to the control without the hormone. In contrast, chondrocytes grown in medium containing IGF-I had a marked increase in cell density after 3 days and presented similar morphologic characteristics to cells grown in the presence of NBS. The growth factors required for proliferation of chondrocytes cultured in the serum-free medium are IGF-I and fibroblast growth factor (100 ng/ml, respectively). Addition of ascorbic acid to the serum-free medium (0 to 50 μg/ml) produced a dose-dependant decrease in cell proliferation. This medium should provide a useful tool for studying the effects of different growth factors/hormones in the regulation of longitudinal bone growth and their interactions.  相似文献   

6.
Summary Past studies using micropatterned substrates coated with adhesive islands of extracellular matrix revealed that capillary endothelial cells can be geometrically switched between growth and apoptosis. Endothelial cells cultured on single islands larger than 1500 μm2 spread and progressed through the cell cycle, whereas cells restricted to areas less than 500 μm2 failed to extend and underwent apoptosis. The present study addressed whether island geometries that constrained cell spreading to intermediate degrees, neither supporting cell growth nor inducing apoptosis, cause cells to differentiate. Endothelial cells cultured on substrates micropatterned with 10-μm-wide lines of fibronectin formed extensive cell-cell contacts and spread to approximately 1000 μm2. Within 72 h, cells shut off both growth and apoptosis programs and underwent differentiation, resulting in the formation of capillary tube-like structures containing a central lumen. Accumulation of extracellular matrix tendrils containing fibronectin and laminin beneath cells and reorganization of platelet endothelial cell adhesion molecule-positive cell-cell junctions along the lengths of the tubes preceded the formation of these structures. Cells cultured on wider (30-μm) lines also formed cell-cell contacts and aligned their actin cytoskeleton, but these cells spread to larger areas (2200 μm2), proliferated, and did not form tubes. Use of micropatterned substrates revealed that altering the geometry of cell spreading can switch endothelial cells among the three major genetic programs that govern angiogenesis—growth, apoptosis and differentiation. The system presented here provides a well-defined adhesive environment in which to further investigate the steps involved in angiogenesis.  相似文献   

7.
By using environmental scanning electron microscopy, the morphological changes of Vero cells attached to and grown on the microcarrier Cytodex-3 were observed, and their behavior of adhesion, spreading and proliferation was analyzed. The effect of exogenous fibronectin/ laminin on adhesion and spreading of MCC/Vero cell was studied. The images of ESEM showed that expansion of cell growth was directed toward vacancy space. The growth curve and cell concentration change during the whole culture process were obtained from the statistical counting method based on ESEM images and the crystal violet method. The growth rate of Vero cells increases with increasing the concentration of cell inoculation, that is, the specific growth rate increases quickly with increasing the concentration of cell inoculation. When serum concentration in medium #199 ranged from 5% to 10%, experimental results indicated that serum concentration is one of the important factors influencing cell growth, particularly in the cell adhesio  相似文献   

8.
To study the cytotoxic effects and antitumour mechanism of norcantharidin(NCTD) on human breast cancer cell, MCF-7 cells were exposed to culture medium with NCTD in different doses and hours. The cell growth inhibition curves of NCTD on MCF-7 cells were acquired by detecting the growth ratio of MCF-7 cells with MTT methods. The results indicated that NCTD had inhibition effects on growth of MCF-7 cells depending on the doses and times of treatment. When the concentrations of NCTD used was lower than 5 μg/ml, the cells grew as same as the control cells. With increasing doses and times of treatment, the inhibition effects of NCTD on the cells' growth increased, for example, when exposed to 10 μg/ml NCTD  相似文献   

9.
Feng RQ  Du LY  Guo ZQ 《Cell research》2005,15(5):401-405
During embryonic development, pluripotent endoderm tissue in the developing foregut may adopt pancreatic fate or hepatic fate depending on the activation of key developmental regulators. Transdifferentiation occurs between hepatocytes and pancreatic cells under specific conditions. Hepatocytes and pancreatic cells have the common endodermal progenitor cells. In this study we isolated hepatic stem/progenitor cells from embryonic day (ED) 12-14 Kun-Ming mice with fluorescence-activated cell sorting (FACS). The cells were cultured under specific conditions. The cultured cells deploy dithizone staining and immunocytochemical staining at the 15th, 30th and 40th day after isolation. The results indicated the presence of insulin-producing cells. When the insulin-producing cells were transplanted into alloxaninduced diabetic mice, the nonfasting blood glucose level was reduced. These results suggested that fetal liver stem/progenitor cells could be converted into insulin-producing cells under specific culture conditions. Fetal liver stem/progenitor cells could become the potential source of insulin-producing cells for successful cell transplantation therapy strategies of diabetes.  相似文献   

10.
Stem cells possess the remarkable ability of extensive self-renewal and differentiation into specific celllineages,and they play essential roles in development and adult tissue homeostasis.Due to their criticalimportance in normal physiology and the promise for use in regenerative medicine to treat a variety ofdiseases,stem cells have attracted extensive research interest in recent years.As China's premium in-ternational journal with a broad scope in cell and molecular biology,Cell Research has witnessed moreand more submissions on stem cell research.Indeed,along with the traditional strengths of the journal inmolecular immunology,cancer biology,and plant molecular physiology,stem cell research has graduallyand naturally evolved into a new growth point of Cell Research.Reflecting the growing interest of bothour readers and authors in this exciting and expanding field,we are pleased to present this Special Issueon Stem Cell Research.  相似文献   

11.
音乐治疗效应的动物实验研究   总被引:1,自引:0,他引:1  
李靖  王旭东 《四川动物》2007,26(1):196-197,200
近年来国内外关于音乐治疗效应的动物实验研究认为:音乐能影响动物的情绪;音乐还对动物的免疫功能、学习及记忆能力、以及动物的神经系统结构和功能等均有一定影响。该领域的研究有利于深入探索音乐疗法的作用机理。  相似文献   

12.
以自制的壳聚糖作为载体,用戊二醛作交联剂,优化了固定化条件,研制成壳聚糖固定化木瓜蛋白酶。其活性回收率达到42—53%,操作半衰期达到一个月以上,对热、乙醇以及尿素的稳定性有很大的提高,Km值为0.67×10~2mg/mL,最适温度65—70℃,最适pH8.0,能使啤酒中的蛋白质浓度从56.5mg/L减少到2.7mg/L,可以消除啤酒的低温混浊现象。  相似文献   

13.
蚕丝固定化脂肪酶的研究   总被引:22,自引:0,他引:22  
研究了蚕丝固定化脂肪酶的工艺条件,并考察了固定化脂肪酶的稳定性。试验结果表明:蚕丝与对-β-硫酸酯乙砜基苯胺(SESA)进行反应的最适条件是PH=10.8,SESA:2.0g/g蚕丝,反应生成的对氨基苯磺酰乙基蚕丝(ABSE-蚕丝)经重氮化后与脂肪酶偶联的最适条件是:pH=7.5,偶联时间>10h。加酶量为168~308u/g蚕丝时,所得固定化脂肪酶活力为106~160u√g蚕丝.此时固定化冀的活力回收率较高(>52%)。固定化脂肪酶稳定性较高.其操作半衰期约为250h。  相似文献   

14.
红树林在防风消浪、促淤保滩、固岸护堤等方面发挥重要的作用,是抵御台风、风暴潮、海岸侵蚀等自然灾害的重要天然屏障。热带气旋是红树林面临的最主要自然威胁之一,削弱了红树林对自然灾害的抵御及生物多性维持等功能发挥。然而,尽管热带气旋对红树林的影响日益受到全球的广泛关注,但缺乏对该领域研究进展的系统分析和总结。以Web of science核心集数据库为数据源,利用CiteSpace软件对1995—2021年间热带气旋对红树林影响研究进行文献计量分析和可视化图谱绘制,以厘清该领域研究的现状、趋势和热点,并揭示未来的发展方向。研究表明:(1)该领域研究年发文量随时间处于波动上升的趋势,尤其2013年后迅速增加,表明该领域的研究日益受到重视;(2)美国、澳大利亚和印度等国家在该领域的研究走在前列,美国的中介中心性最高,其次是德国,美国广泛地与德国、法国、日本等许多国家有密切合作;(3)美国佛罗里达、加勒比地区、澳大利亚北部和印度南部等是当前研究的热点区域;(4)研究热点随时间推移而不断发展,从红树林植被的干扰损害逐渐发展到固碳储碳、海岸防护等功能的影响。全球变化背景下热带气旋对红树林的影响、红树林对热带气旋干扰的弹性、基于遥感和大数据处理的模型模拟等日益受到关注,量化热带气旋对红树林功能的影响、探明热带气旋与海平面上升的关系及对红树林影响、构建完善的观测体系数据集等将是未来研究的重要方向。研究对长期关于热带气旋对红树林影响的研究进展进行定量和可视化分析,可为预测热带气旋对红树林的影响和风险、及减缓和应对其风险等研究提供借鉴参考。  相似文献   

15.
目的 探究芦笋对高脂饮食小鼠体质量的影响。方法 将实验动物随机分为正常组、高脂饮食组、高脂饮食低剂量芦笋组、高脂饮食中剂量芦笋组、高脂饮食高剂量芦笋组、高脂饮食阳性对照组。其中正常组喂食正常饲料,其余组喂食高脂饲料。分别灌胃蒸馏水(正常组、高脂饮食组)、芦笋1.05 g/(kg•d)(高脂饮食低剂量芦笋组)、芦笋2.10 g/(kg•d)(高脂饮食中剂量芦笋组)、芦笋4.20 g/(kg•d)(高脂饮食高剂量芦笋组)、降脂理肝汤1.19 g/(kg•d)(高脂饮食阳性对照组),每天2次,每次0.35 mL。比较分析各组小鼠的体质量变化,同时对各组之间的雌性小鼠和雄性小鼠体质量变化进行对比。结果 随饲养时间的增加,服用芦笋后的三组小鼠体质量均低于高脂饮食组,但与高脂饮食组相比差异无统计学意义(P>0.05)。高脂饮食低剂量芦笋组、高脂饮食中剂量芦笋组、高脂饮食高剂量芦笋组小鼠的体质量变化率低于高脂饮食组,差异无统计学意义(P>0.05)。对各组之间的雌性小鼠和雄性小鼠体质量变化进行对比可以发现雄性小鼠的体质量变化大于雌性小鼠的,差异有统计学意义(P<0.05)。结论 芦笋能降低高脂饮食小鼠的体质量,雄性小鼠和雌性小鼠的体质量变化存在差异。  相似文献   

16.
Planktivory by fingerling kokanee Oncorhynchus nerka feeding on Daphnia became more size-selective with increased illumination (0·1 v . 15 lux). The average difference in length of Daphnia ( D. pulex and D. galeata ) in trial arenas before and after kokanee feeding was 0·107 mm ( P  = 0·0007) at 0·1 lux and 0·371 mm ( P  < 0·0001) at 15 lux.  相似文献   

17.
本文阐述了心理对生理的能动作用。在一定的条件下,人的心理可影响其生理功能,两者互为因果、相互影响。生理是心理活动的物质基础,心理是其生理的驱动力和标志。本文论述了精神、情绪、意念、信念、暗示等心理活动对生理的影响和作用及中医论心理对生理的作用,中医利用情志疗法的理论达到心理对生理趋向健康的作用。同时论证了肠道菌群通过心理间接影响生理功能,通过微生态制剂调节肠道菌群的微生态平衡,可改善患者的神经症状,使之心理活动达到最佳状态,进而使人的生理趋向健康。  相似文献   

18.
若羌红枣多糖提取方法的研究   总被引:1,自引:0,他引:1  
目的:比较研究几种提取若羌红枣多糖的方法.方法:通过正交实验设计研究影响若羌红枣多糖提取的诸因素如提取料液比、温度、提取时间、提取次数等,确定条件范围,优化提取条件,得到提取若羌红枣多糖的最佳工艺条件.结果:热水法提取红枣糖的最佳条件:提取温度100℃、料液比1:16、提取时间4h,提取1次;酶法提取红枣多糖提取的最佳条件:pH4.5,温度60℃、时间1h,酶用世0.03%;碱法提取红枣多糖的对佳条件:Na2 CO3,温度80℃、时间3h,料液比1:20.结论:三种提取方法以酶提取法的效率最高,碱提取法次之,热水提取法的效率最低.  相似文献   

19.
放牧对草场植被动态的影响   总被引:7,自引:1,他引:6  
放牧对草场植被动态的影响吴德东,周景荣,朱德华,刘淑玲(辽宁省固沙造林研究所,章古台123203)王志海,马占信,赵建平(阜新市阿尔乡畜牧场,123204)InfluenceofGrazingonVegetationDynamicsonPasture...  相似文献   

20.
探讨丹皮酚(Pae)拮抗过氧亚硝基阴离子(ONOO^-)对体外培养大鼠成骨细胞分化的影响。用改良的组织块法分离培养新生大鼠颅骨成骨细胞,采用淬灭流动反应方法体外制备ONOO^-,以不同终浓度加入成骨细胞培养体系,在作用不同时间后,用对硝基苯二钠动力学(PNPP)法检测细胞内碱性磷酸酶(ALP)的活性,用Lowry法测定蛋白含量,并以不同终浓度Pae消除ONOO^-(1000μmoL/L)对成骨细胞分化的影响。结果显示,不同浓度的ONOO^-(50-1000μmoL/L)均能抑制碱性磷酸酶的活性,影响分化;高浓度的丹皮酚(10^-3-10^-6mol/L)能消除ONOO^-(1000μmoL/L)对碱性磷酸酶活性的抑制,拮抗ONOO^-抑制成骨细胞分化的作用。  相似文献   

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