不同浓度6-BA及KT对马铃薯无菌苗诱导的影响

以‘高原7 号’马铃薯茎尖为外植体,用0.1%升汞和75%酒精消毒,经组织培养获得脱毒马铃薯茎段,在增殖培养中,研究不同浓度6-BA 及KT 对马铃薯茎段诱导增殖效果的影响。结果表明：用0.1%升汞对茎尖消毒8 min 效果最好,灭菌率达96.67%。细胞分裂素对马铃薯茎段增殖的促进作用为6-BA>KT,以1.5 mg/L 6-BA 诱导不定芽及其生长势效果最佳。     

红枫杜鹃的组培快繁与规模化生产

1植物名称 红枫杜鹃（Rhododenron molle×Rhododendron schlippenbachii）。 2材料类别 茎段、茎尖。 3培养条件 基本培养基为MS。（1）诱导愈伤组织培养基：1／4MS＋ZT4．0mg·L^-1（单位下同）＋NAA0．1＋2,4．D0．03;（2）继代培养基：1／4MS＋ZT1．0＋NAA0．1;（3）壮苗培养基：1／4MS＋ZT0．5＋NAA0．05;     

细胞生长因子对冠状动脉内皮细胞增殖与迁移的影响

目的 :观察肝细胞生长因子 (HGF)和血管内皮细胞生长因子 (VEGF)对体外培养牛冠状动脉内皮细胞(BCAEC)增殖、迁移的影响。方法 :分离和培养BCAEC ,设对照组、VEGF组、HGF组。采用四甲基偶氮唑蓝法(MTT)观察细胞增殖 ;倒置显微镜观察培养的血管内皮细胞的迁移。结果 :对照组、VEGF组、HGF组的OD值分别为 0 .2 2± 0 .0 1、0 .40± 0 .1 4、0 .44± 0 .1 5 ;VEGF组、HGF组BCAEC的增殖率分别为 81 .8%± 1 6 .9%、1 0 0 %±2 1 .1 % ;对照组BCAEC迁移不明显 ,而VEGF组和HGF组BCAEC迁移明显。结论 :VEGF、HGF能促进BCAEC增殖、迁移 ,HGF作用强度不亚于VEGF。     

中药M对兔内皮细胞增殖影响的初步研究

目的　旨在探讨中药M对兔内皮细胞增殖的影响 ,试图阐明单味中草药品种M的活性成分促进血管生成的生物学机制。方法　建立兔胸主动脉内皮细胞体外培养模型 ,制备不同浓度的兔中药血清加入 96孔内皮细胞培养板 ,以MTT比色法测定内皮细胞增殖情况。结果　生脉素能够促进内皮细胞的增殖 (P <0 0 5 )。结论　中药M可能通过促进内皮细胞的增殖和分裂而达到其促进血管生成的作用     

白藜芦醇对乳腺癌细胞MCF-7 增殖的影响

目的:研究白藜芦醇体外活性,确定它的植物雌激素作用。方法:采用MTT法观察不同浓度白藜芦醇对MCF-7细胞增殖作用的影响。采用DNA ladder法和荧光显微镜观察高浓度白藜芦醇对细胞的影响。免疫组化法观察低浓度白藜芦醇对核增殖抗原PCNA表达的影响。结果:MTT结果显示白藜芦醇高浓度抑制MCF-7细胞增殖,IC50为8.70×10-5mol/L;低浓度(10-7~10-6mol/L)则对细胞有促增殖作用,最高促增殖浓度为1.0×10-7mol/L。DNA ladder和荧光显微镜可观察到高浓度白藜芦醇作用后细胞典型的凋亡形态。免疫组化结果显示低浓度白藜芦醇作用后,细胞核内PCNA表达明显增加(P<0.05)。结论:高、低浓度的白藜芦醇对MCF-7细胞分别表现为诱导凋亡和促增殖作用,呈现出植物雌激素对MCF-7细胞典型的双向调节作用。     

白藜芦醇对乳腺癌细胞MCF-7增殖的影响

目的：研究白藜芦醇体外活性,确定它的植物雌激素作用。方法：采用MTT法观察不同浓度白藜芦醇对MCF-7细胞增殖作用的影响。采用DNA ladder法和荧光显微镜观察高浓度白藜芦醇对细胞的影响。免疫组化法观察低浓度白藜芦醇对核增殖抗原PCNA表达的影响。结果：MTT结果显示白藜芦醇高浓度抑制MCF-7细胞增殖,IC50为8.70×10-5mol/L;低浓度（10-7~10-6mol/L）则对细胞有促增殖作用,最高促增殖浓度为1.0×10-7mol/L。DNA ladder和荧光显微镜可观察到高浓度白藜芦醇作用后细胞典型的凋亡形态。免疫组化结果显示低浓度白藜芦醇作用后,细胞核内PCNA表达明显增加（P〈0.05）。结论：高、低浓度的白藜芦醇对MCF-7细胞分别表现为诱导凋亡和促增殖作用,呈现出植物雌激素对MCF-7细胞典型的双向调节作用。     

6-BA、IBA、2,4-D对杖藤组培增殖的影响

研究了6 BA、IBA和2,4 D对杖藤组培物增殖的影响。结果表明,6 BA对增殖芽数、丛芽率和母芽高均有显著的作用,IBA和2,4 D仅对增殖芽数有显著影响。适宜于增殖培养的激素浓度分别为6 BA4.0mg/L,IBA0.25mg/L,2,4 D0.25mg/L。以此激素浓度组合,连续增殖培养6～7代后,平均的增殖芽数可稳定在10个左右。     

姜黄素对胃癌细胞系HGC-27增殖及侵袭力的影响

目的:探讨姜黄素(curcumin,Cur)对胃癌细胞系HGC-27细胞增殖及侵袭力的影响以阐明Cur的抗瘤机制。方法:采用MTT法检测不同剂量(0、10、20、30、40?mol/L)及不同处理时间(24、48、72h)的姜黄素对HGC-27细胞增殖活性的影响;Transwell侵袭实验检测姜黄素对HGC-27细胞侵袭力的抑制作用。结果:1.MTT法显示姜黄素显著抑制HGC-27细胞增殖,20μmol/L,30μmol/L,40μmol/L姜黄素处理72小时其生长抑制率分别为24.63%,32.42%,76.43%,有明显的剂量及时间依赖性,不同剂量组之间及不同处理时间组之间比较有差异显著性(P<0.05)。2.Transwell侵袭实验显示姜黄素显著抑制HGC-27细胞的侵袭力,呈剂量和时间依赖性,各剂量组与对照组比较差异有显著性(P<0.05)。结论:姜黄素通过抑制HGC-27细胞增殖和侵袭行为起到抗肿瘤作用。     

低氧对大鼠肺动脉平滑肌细胞pHi及细胞增殖、凋亡的影响

目的: 探讨低氧肺血管结构重建时是否伴有PASMCs凋亡.方法: 体外低氧培养大鼠PASMCs,BCECF法测定细胞内pH值、光镜及电镜观察细胞形态、流式细胞仪测细胞周期、原位细胞凋亡(TUNEL法)观察细胞凋亡.结果: PASMCs在低氧早期即出现细胞内碱化,低氧6 h即出现G0/G1期细胞比例减少,G2/M期细胞比例增加,至24 h丝裂活动最强,但细胞凋亡率无显著变化.结论: 低氧PASMCs在细胞内碱化、细胞增殖的过程中不伴有细胞凋亡的改变.     

过表达Nogo-C对PC12细胞存活及增殖的影响

以PC12细胞为神经元细胞模型,研究Nogo-C对神经元细胞存活及增殖的作用。在PC12细胞中转染过表达Nogo-C,使用G418药物筛选以获得稳定表达的细胞克隆,利用Hoechst33342染色、细胞计数、MTT以及流式细胞仪等技术检测Nogo-C对细胞增殖以及细胞周期的影响。结果表明:(1)Hoechst33342染色未观察到表达Nogo-C的细胞发生明显凋亡;(2)细胞计数及MTT实验观察到转染Nogo-C后的PC12细胞生长增殖活性明显降低;(3)流式细胞仪检测细胞生长周期,正常PC12细胞G1期的百分数为(37.8±7.9)%,S期为(50.4±8.5)%,而转染Nogo-C的PC12细胞G1期为(76.8±4.1)%,S期为(14.7±1.7)%,提示转染Nogo-C的PC12细胞的细胞周期被阻滞在G1期;(4)没有获得稳定表达Nogo-C的PC12细胞模型。实验证明,过表达Nogo-C通过使PC12细胞周期被阻滞在G1期而明显抑制细胞的增殖,但是并不引起细胞的凋亡。     

Developmental control of cell division patterns in the shoot apex

The shoot apical meristem is a group of rapidly dividing cells that generate all aerial parts of the plant. It is a highly organised structure, which can be divided into functionally distinct domains, characterised by specific proliferation rates of the individual cells. Genetic studies have enabled the identification of regulators of meristem function. These factors are involved in the formation and maintenance of the meristem, as well as in the formation of the primordia. Somehow, they must also govern cell proliferation rates within the shoot apex. Possible links between meristem regulators and the cell cycle machinery will be discussed. In order to analyse the role of cell proliferation in development, cell cycle gene expression has been perturbed using transgenic approaches and mutation. The effect of these alterations on growth and development at the shoot apex will be presented. Together, these studies give a first insight into the regulatory networks controlling the cell cycle and into the significance of cell proliferation in plant development.     

Plant stem cells and their regulations in shoot apical meristems

Stem cells in plants, established during embryogenesis, are located in the centers of the shoot apical meristem (SAM) and the root apical meristem (RAM). Stem cells in SAM have a capacity to renew themselves and to produce new organs and tissues indefinitely. Although fully differentiated organs such as leaves do not contain stem cells, cells in such organs do have the capacity to re-establish new stem cells, especially under the induction of phytohormones in vitro. Cytokinin and auxin are critical in creating position signals in the SAM to maintain the stem cell organizing center and to position the new organ primordia, respectively. This review addresses the distinct features of plant stem cells and focuses on how stem cell renewal and differentiation are regulated in SAMs.     

Cell Differentiation and Organ Initiation at the Shoot Apical Meristem

Plants continuously generate organs at the flanks of their shoot apical meristems (SAMs). The patterns in which these organs are initiated, also called patterns of phyllotaxis, are highly stereotypic and characteristic for a particular species or developmental stage. This stable, predictable behaviour of the meristem has led to the idea that organ initiation must be based on simple and robust mechanisms. This conclusion is less evident, however, if we consider the very dynamic behaviour of the individual cells. How dynamic cellular events are coordinated and how they are linked to the regular patterns of organ initiation is a major issue in plant developmental biology.     

Is the extent of the proliferation of component cell lineages critical during organ morphogenesis?

Shoot meristems of higher plants are composed of several clonally distinct cell lineages. Periclinal chimeras have been used to determine the fate of derivatives of these lineages in mature leaves and other organs of the plant. Fates of individual meristem cells are not rigidly fixed and the distribution of tissue derived from each meristem lineage in different regions of an organ is variable. The amount of proliferation from an individual lineage can be altered without affecting the overall morphology of organs. Mechanisms exist by which cells from several lineages coordinate their relative amounts of proliferation. The conclusion from these studies is that cell proliferation and organ morphogenesis are developmental events that can be uncoupled.     

CENTRORADIALIS maintains shoot meristem indeterminacy by antagonizing THORN IDENTITY1 in Citrus

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植物干细胞培养研究进展

植物干细胞位于分生组织,是处于未分化状态的细胞,液泡化程度低,具有较高的线粒体活性,遗传稳定,具有很强的自我更新和再生能力。植物干细胞培养在下游制药和功能性食品以及化妆品行业具有广泛的应用潜质。文中综述了植物干细胞的基本培养技术、鉴别技术,为该领域的深入研究提供参考。