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1.
    
The effects of low energy nitrogen ion implantation on Ca2+ concentration and membrane potential of lily (lilium davidii Duch) pollen cell have been studied. The results showed that the Ca2+ concentration was increased when pollen grain was implanted by nitrogen ion with energy 100 keV and dose 1013 ions/cm2. However, the increase of Ca2+ concentration was partly inhibited by the addition of Ca2+ channel inhibitor depending on dose. And nitrogen ion implantation caused depolarization of pollen cell membrane potential. In other words, membrane potential was increased, but the effect decreased by adding Ca2+ channel inhibitor. However, it was still significantly higher than the membrane potential of control cells. It was indicated that the depolarization of cell membrane potential opened the calcium channel on the membrane that caused the increasing of intracellular calcium concentration. This might be an earlier step of the effect of low energy nitrogen ion implantation on pollen germination.  相似文献   

2.
The elongation of pollen tube is an important process of sexual reproduction in higher plant. Cytoskeleton plays a major regulatory role in the elongation of pollen tubes. But whether membrane skeleton is involved in the pollen tube elongation is not clear. In this study, immunochemical detection of spectrin-like protein has been carried out in pollen tubes. By use of 2-dimensional electrophoresis(2DE) and western blotting, two spectrin-like proteins are found, one is 150 kD, and the other is 105 kD, with pl being 4.54 and 4.39, respectively. 150 kD spectrin-like protein is located in plasma membrane of pollen tube and 105 kD spectrin-like protein is located in cytoplasm, probably functioning as a subunit to form a dimmer (210 kD) in vivo. The elongation of pollen tubes is inhibited after spectrin antibody was injected into a growing pollen tube. These results suggest that spectrin-like proteins exist in pollen tube and play an important regulating role in the elongation process of pollen tubes from lily.  相似文献   

3.
  总被引:1,自引:0,他引:1  
Actin and myosin from pollen tubes of Lilium davidii were studied by using immunoblotting, Dot_Blot and myosin Ca 2+_ATPase analysis. On immunoblotting of the total soluble pollen tube proteins, anti_α_actin antibody labelled a polypeptide approximately 43 ku, which is considered to be the actin of lily. The mRNA encoding actin in ungerminated pollen and germinated pollen were both undetectable in our experiments. A myosin exhibited Ca 2+_ATPase activity, with a native molecular weight of 460 ku has been identified by using immunoblotting. A polypeptide of about 205 ku and a polypeptide of about 20 ku were the heavy chain and a set of light chain of the myosin, which can crossreact with anti_skeletal muscle myosin heavy chain monoclonal antibody and anti_skeletal muscle myosin light chain (20 ku) monoclonal antibody, respectively. The Ca 2+_ATPase activities of myosin in crude extracts of germinated pollen were positively related to the growth rates of pollen tubes.  相似文献   

4.
    
Liliaceous pollen cells were implanted by 4.0 MeV C2+ ion beam or by 25.0 keV N+ ion beam. Laser confocal scanning microscopy (LCSM) of the implanted intact samples showed that parts of the implanted pollen cells could be stained by propidium iodide (PI). This indicated that energetic ion beam could directly act on cells beneath the pollen coats and made channels for entry of the molecules from outside of the cells. LCSM analysis of green fluorescent protein (GFP) showed that energetic ion beam could mediate transient expression of gfp in treated pollen cells. Compared with 25.0 keV N+ ion beam, implantation of 4.0 MeV C2+ ion beam greatly improved gene transfer efficiency in pollen cells.  相似文献   

5.
Anewtechniqueofgenetransfermediatedbyenergeticionbeamirradiationorimplantationwasde velopedinrecentyears .Stokeretal.[1] foundthatthesusceptibilityofcricetidaeembryocellstoaden ovirustransformationwassignificantlyimprovedbyX rayradiation .Stevensetal.[2 ] andZengetal.[3]foundthatpreliminarytransferrateofplasmidDNAcouldbeimprovedtoalargedegreebyionizingradia tion .UV[4 ] andenergeticheavyions[5] werefoundtohavesimilareffects ,whichindicatedthationizingra diationcouldmakeiteasyforextraneousDN…  相似文献   

6.
对低能氮离子注入甜菊种子引起的生长发育、细胞核和染色体形态结构的影响进行研究。结果表明,能量为75KeV,剂量为10^14/cm^4的氮离子束主甜菊种子后,种子萌发率下降;幼苗期生长迟缓;细胞分裂指数下降,异常细胞核和染色体畸变增加,细胞核膜凹凸不平,核仁解聚,部分核质凝集并被凹陷的核膜包被成颗粒化小区,进而形成 核,细胞核的形态建设和细胞分裂受到一定的干扰,推测这些现象与幼苗期处理种子的早期生长  相似文献   

7.
    
The assembly of microtubules is essential for physiological functions of microtubules. Addition of microtubule-stabilizing reagents or microtubule \"seeds\" is usually necessary for plant tubulin assembly in vitro, which hinders the investigation of plant microtubule dynamics. In the present note, highly purified plant tubulins have been obtained from lily pollen, a non-microtubule-stabilizing reagent or microtubule \"seed\" system for plant tubulin assembly has been established and the analysis of plant tubulin assembly performed. Experiment results showed that purified tubulin polymerized in vitro, and a typical microtubule structure was observed with electron microscopy. The kinetics curve of tubulin assembly exhibited typical \"parabola\". The presence of taxol significantly altered the character of plant tubulin assembly, including that abnormal microtubules were assembled and the critical concentration for plant tubulin assembly was decreased exceedingly from 3 mg/mL in the absence of taxol to 0.043 mg/mL in the presence of taxol.  相似文献   

8.
The assembly of microtubules is essential for physiological functions of microtubules. Addition of microtubule-stabilizing reagents or microtubule “seeds” is usually necessary for plant tubulin assemblyin vitro, which hinders the investigation of plant microtubule dynamics. In the present note, highly purified plant tubulins have been obtained from lily pollen, a non-microtubule-stabilizing reagent or microtubule “seed” system for plant tubulin assembly has been established and the analysis of plant tubulin assembly performed. Experiment results showed that purified tubulin polymerizedin vitro, and a typical microtubule structure was observed with electron microscopy. The kinetics curve of tubulin assembly exhibited typical “parabola”. The presence of taxol significantly altered the character of plant tubulin assembly, including that abnormal microtubules were assembled and the critical concentration for plant tubulin assembly was decreased exceedingly from 3 mg/mL in the absence of taxol to 0.043 mg/mL in ihe presence of taxol.  相似文献   

9.
用C语言编制程序对钛离子注入芸豆子叶的离子浓度随注入深度变化的实验曲线进行数学拟合,找到描述该实验曲线的数学函数,并调试出函数的有关参数值,由该函数可以计算出注入到子叶某一深度层面上单位体积内的离子数平均值。  相似文献   

10.
陶瓷材料的表面性能在很大程度上取决于其表面条件.例如:陶瓷的表面微裂纹影响着机械强度,而磁学及电学性能则对其表面结构及化学成份非常敏感.近年来离子注入法已经开辟了研制现代材料的新途径,并被广泛应用于金属、半导体及部分聚合物材料中.对于陶瓷材料,目前大多数有关这方面的研究集中于改善陶瓷表面的机械性能,很少有论文涉及其表面电性能的改善.本文介绍了一种改善ZrO2陶瓷表面导电性能的新方法.ZrO2陶瓷是绝缘体,常温下其电阻率大于1012Ωcm.通过不同剂量的离子注入可以使得样品表层产生不同程度的电性能变化.试验表明,当采用2×1017Fe/cm2注入,并在950℃下真空退火30分钟,ZrO2的表面电阻率将下降十余个数量级,从而大幅度提高了样品的导电性.文中还通过应 用X射线衍射及光电子能谱技术,分别对注入元素的化学结合状态及表面注入层的结晶相进行了较为详细的讨论.从XPS测试发现,注入离子在ZrO2表层中以Fe2+、Fe3+及Fe0三种形式的状态存在;X射线衍射数据表明,注入层中除ZrO2主晶相外,还存在少量的FeZrO3等晶相.文章的最后部分讨论了离子注入样品的导电机制.  相似文献   

11.
本文研究了硅中离子注入层的卤钨灯辐照快速退火,对注B 和注P 样品分别测量了经1100℃、15秒和1050℃、12秒退火后注入层的载流子浓度分布,并与950℃、30分钟常规热退火样品作了比较;结果表明,卤钨灯辐照快速退火具有电激活率高、注入杂质再分布小及易于推广使用等优点.对于100keV、1×10~(15)cm~(-2)P 注入样品,经1050、10秒卤钨灯辐照退火后,表面薄层电阻为74.8Ω/□;对通过920(?)SiO_2膜,25keV、1×10~(15)cm~(-2)B 注入样品,经1100℃、15秒卤钨灯辐照快速退火后表面薄层电阻为238.0Ω/□;而经过950℃、30分钟常规热退火后,以上两种样品的表面薄层电阻分别为72.0Ω/□和245.8Ω/□.采用这种退火方法制作出了结深为0.10μm 的近突变P~ N 结,并测量了结深与退火时间的关系.  相似文献   

12.
本文应用剥层椭偏光法对硅中大剂量P~ 注入形成的非晶层在CWOO_2激光退火时的固相外延模型进行静态实验证明.获得CWCO_2激光退火的固相外延生长平均速率达到4.2×10~3(?)/sec.本文并应用隐式差分方法计算了退火样品的体内温度的径向分布T(r,t)及离子注入非晶层外延再结晶厚度的径向分布ξ(r,t)的离散值,得到选择退火条件的一些依据.  相似文献   

13.
研究了高剂量(7.5×10~(15))氩离子注入硅片背面的吸杂效应;吸杂效果由npn晶体管的漏电流,Iceo的降低得到证实;分别用SIMS及DLTS法测量吸杂前后杂质分布的变化。结果表明,Fe、Cr及Au等重金属杂质经吸杂处理后有效地从硅片正面的有源区转移到背面的损伤区,揭示了吸杂的实际过程。  相似文献   

14.
在顶非晶化硅衬底上淀积Ti金属膜,经600℃及850℃.60分钟退火形成硅化钛.在Ti硅化过程中释放的空位能消除硅衬底上的射程端缺陷.而没有淀积Ti膜的预非晶化硅样品,即使退火温度高达1000℃,射程端缺陷也不能完全被消除.  相似文献   

15.
本文应用扫瞄电镜观察低能铜离子注入绿豆(PhaseolusaureusRoxb.)种胚后子叶细胞结构的变化情况,并对注入前后种胚内部淀粉和蛋白质的含量进行了测试.试验证明离子注入后种胚内部淀粉含量和蛋白质的成份都发生了变化.  相似文献   

16.
粤北食用百合的N,P,K配比施肥研究   总被引:2,自引:0,他引:2  
针对粤北种植百合的土壤pH值普遍偏酸性,通过在大田中试验发现,有机质含量缺乏,缺钾严重,氮素含量中等,磷素含量充足,采用NPK 3因子3水平正交设计,经多重比较,以处理3(N∶P∶K为1∶3∶3)的效果最佳。N,P,K配比施肥结果表明重施钾肥增产效果显著。  相似文献   

17.
采用锗材料研制出了工作在 1.55μm波长的全离子注入光电晶体管 .选用 (12 0 keV ,2 .5× 10 12 cm- 2 ) +(2 6 0keV ,5× 10 12 cm- 2 )的硼注入和 16 0keV ,5× 10 14 cm- 2 磷注入 ,6 50℃ 15s快速退火 ;采用聚酰亚胺作为钝化膜以及台面结构 .NPNGe光电三极管的hFE=4 0~ 180 .在波长为 1.55μm、功率为 0 .7μW的光照下得到了 4 0 A·W- 1的响应度  相似文献   

18.
采用加热靶和少量氮离子注入制成了 SOI 材料,在1180℃、氮气保护下进行了2小时的退火。离子沟道背散射测量和电子通道花样观测结果表明:加热靶和少量氮离子注入能有效地改善顶部硅层的单晶质量.  相似文献   

19.
离子注入对玻璃材料的改性   总被引:1,自引:0,他引:1  
简要地评述了离子注入对玻璃风化、化学稳定性、晶化和非线性光学性质的影响。指出采用离子注入法,在不影响磷酸盐玻璃重要性质的前提下,提高其化学稳定性;锂硅酸盐玻璃在注入Nd^+后,可提高玻璃的耐水性。强调指出离子注入在玻璃改性上有着广泛的应用前景。  相似文献   

20.
(Si,Er)双注入单晶硅近红外光发射   总被引:1,自引:0,他引:1  
利用金属蒸气真空弧离子源,将硅和铒离子先后注入到单晶硅中,经快速退火制备出(Si,Er)双注入单晶硅发光薄膜,RBS分析表明铒原子分接受10%,即原子浓度约10^21cm^-3,XRD分析发现,随着Er注量增加,退火态样品中ErSi2相增多,显微结构分析表明,注量条件影响辐照损伤程度、物相变化和表面显微形貌,而这些结构变化将直接决定(Si,Er)双注入单晶硅发光薄膜近红外区光致发光。  相似文献   

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