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1.
目前一般认为长时程增强效应(long-termpotentiation,LTP)和哺乳动物大脑学习记忆的机制有关。本文简述了视皮层中LTP的诱导,产生的关键期以及LTP在脑皮层功能柱的不同层中的差异。讨论了N-甲基-D-氨基丁酸(N-methyl-D-aspartate,NMDA)受体、低阈值Ga2+通道(low-thresholdCa2+channels,LTCs)在LTP诱导过程中的作用,以及视皮层LTP和海马LTP的差异。  相似文献   

2.
应用生态学报第5卷(1994)关键词索引CHINESEJOURNALOFAPPLIEDECOLOGYVol.5(1994)KEYWORDINDEXAAcanthopanaxsenlicosusigloo5(3):237Agroecosystem¥k4...  相似文献   

3.
以我国栗疫菌[Cryphonectria(=Endothia)parasitica]低毒力菌株EpC140(广西)的[γ─ ̄32P]ATP末端标记dsRNA作探针,与5种真菌病毒dsRNA进行分子杂交。探针可与紫孢侧耳病毒(Pleurotussepidusvius)和小麦全蚀菌病毒(Gaeuman─nomycesgraminis·virus)的dsRNA杂交,但不能与黑曲霉病毒(Aspergillusnigervirus)、产黄青霉病毒(Penicilliumchrysogenumvirus)和稻瘟菌病毒(Pyriculariaoryzaevirus)的dsRNA杂交。当以低毒力菌株EpC32(云南)作探针时,结果相同。  相似文献   

4.
应用生态学报第6卷(1995)关键词索引KEYWORDINDEXCHINESEJOURNALOFAPPLIEDECOLOGYVol.6(1995),、A*——你小叽用橡树以’):‘”Accumulationanddes。dation积累与降解必(’)...  相似文献   

5.
梁平彦  全勇 《病毒学报》1995,11(1):72-77
以我国栗疫菌(Cryphonectria(=Endothia)parasitica)低毒力菌株EpC140(广西)的(γ-^32P)ATP末端标记dsRNA作探针,与5种真菌病毒dsRNA进行分子杂交。探针可与紫孢侧耳病毒(Pleurotus sapidus virus)和小麦全蚀菌病毒(Gaeuman-nomyces graminis.virus)的dsRNA杂交,但不能与黑曲霉病毒(Pyric  相似文献   

6.
视皮层LTP维持阶段的突触形态计量学研究   总被引:6,自引:0,他引:6  
Chen YC  Han TZ  Shen JX  Qiao JT 《生理学报》1999,51(1):73-79
本实验使用18~20d的幼年大鼠视皮层脑片标本,在LTP出现后3h取局部微脑片固定进行LTP维持阶段超微结构的研究。分别与孵育相同时间而未予任何刺激的脑片和仅给予测试刺激的脑片作比较。运用图像分析仪分别对三组电镜结果进行以下参数的测量:(1)突触间隙的宽度;(2)突触后致密物(PSD)的厚度;(3)活性区的长度;和(4)突触界面曲率。用双盲法对突触数目进行计量,并用立体计量学方法对各种突触类型进行定量,所得数据用方差分析进行统计学处理。结果显示:(1)LTP形成后15h左右,其反应达到峰值,然后维持在最高水平一直到3h仍无下降趋势;(2)突触间隙的宽度较两个对照组明显增宽;(3)PSD的厚度也明显增厚;(4)活性区的面密度及突触界面曲率明显增加;(5)总突触数目和棘突触数目的数密度较空白对照明显增高;(6)穿孔性突触的数密度与对照组相比明显增加。结果提示:活性区面密度的增加及突触界面曲率的增大可能是LTP维持的形态学基础。穿孔性突触的形成与LTP的维持密切相关。  相似文献   

7.
雷富民 《生态学报》1996,16(3):333-336
纵纹腹小(Athenenoctuaplumipes)的种群密度及生态分布格局研究雷富民(中国科学院动物研究所,北京,100080)ONPOPULATIONDENSITYANDECOLOGICALDISTRIBUTIONPATTERNSOFTHELI...  相似文献   

8.
一种优化的植物组织RNA原位杂交技术   总被引:8,自引:1,他引:7  
一种优化的植物组织RNA原位杂交技术①陈绍荣毕学知吕应堂杨弘远(武汉大学生命科学学院,武汉430072)AOptimizedinSituRNAHybridizationTechniqueinPlantTisuesCHENShaorongBIXuezh...  相似文献   

9.
水稻脂质转移蛋白基因的分离和分析   总被引:3,自引:0,他引:3  
用水稻脂质转移蛋白(lipidtransferprotein,LTP)的cDNA(pFDRSC110)为探针,从水稻(OryzasativaL.sp.indica)“广陆矮4号”基因文库中筛选出LTP基因,完成了1.8kb长片段的序列测定。该基因编码一个121个氨基酸组成的肽,编码区中间有一个90bp的内含子,基因的调控区除有2个TATAbox和polyA加工信号外,还存在多个回文序列和逆向重复序列。该基因编码的蛋白质N端是由28个氨基酸组成的信号肽,同源性比较表明它具有典型的植物LTP特征。  相似文献   

10.
本文使用15-20天龄幼年大鼠视皮层脑片的标本,在通氧状态下,用荧光探针AO染色,激光扫描共聚焦显微镜对全脑片不同层面进行共聚焦断层扫描,沿纵轴每20μm扫一次,共扫描16次。再利用总值方式的投影算法对其三维重建,分析幼年大鼠视皮层脑片长时程增强过程中核酸的变化。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

13.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

14.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

15.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

16.
The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.  相似文献   

17.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

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20.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

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