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1.
FEN—1基因反义阻断细胞株(FL—FEN—1^—)的建立   总被引:2,自引:0,他引:2  
FEN-1是一咱结构特异性核酸酶,它在DNA复制和修复过程中都起着重要的作用。将FEN-1基因的NcoI-BamHI片段反向克隆到哺乳动物细胞重组表达质粒pMAMneoAmp^-中,得到FEN-1反义表达质粒pMAMneoAmp^-FNB^-,并转染FL细胞,经G418筛选后,获得FEN-1基因表达被阻断的哺乳动物细胞FL-FEN-1^-。对细胞生长曲线的测定发现,FL-FEN-1^-在地塞米松的  相似文献   

2.
大鼠左心房α1受体及其亚型对β受体正性变力效应的影响   总被引:5,自引:0,他引:5  
张幼怡  禹更生 《生理学报》1994,46(5):473-479
本文用放射配体结合实验研究了α1-肾上腺素受体(α1-AR)及亚型在大鼠左心房的分布。结果表明,大鼠左心房α1-AR有α1A与α1B两种亚型,α1A亚型约占1/3,α1B亚型占2/3。离体灌流左心房功能实验结果表明,α1-AR不同亚型对β肾上腺素受体(β-AR)所介导的正性变力反应具有不同性质的协同作用。当酚妥拉明10μmol/L同时阻断α1A与α1B亚型时,NE(同时激动α1-与β-AR)的剂量-收缩效应曲线显著左移,当用CEC20μmol/L预处理以阻断α1B亚型时,NE的剂量-收缩效应曲线则显著右移,而用WB41011nmol/L阻断α1A亚型后,NE的剂量-收缩效应曲线出现左移;此外,当用苯肾上腺素激动α1-AR时,异丙肾上腺素的剂量-收缩效应曲线亦显著右移。提示α1A亚型可抑制β-AR介导的正性变力效应,而α1B亚型则可增强β-AR所介导的反应,但当α1-AR的上述两种亚型同时激动时,则以α1A亚型的调节作用为主。  相似文献   

3.
HCV核心蛋白免疫优势肽AA32—45抗原化抗体的构建   总被引:1,自引:0,他引:1  
经定点突变,在抗HBsAg单克隆抗体重链V区产生一个XhoI位点并插入编码HCV核心蛋白免疫优势肽AA32 ̄45的互补寡核苷酸片段,构成抗原化VH基因。抗原化VH与人γ3恒区cDNA拼接成嵌合重链基因并与嵌合轻链基因共同构建成杆状病毒表达系统转移载体,经共转染筛选到重组病毒BacHL-E1和BacHL-E2,感染Sf9细胞分别表达Ig-E1和Ig-E2。Ig-E1与正常免疫球蛋白分子一样能形成四聚  相似文献   

4.
用戊肝病毒(HEV)基因组编码氨基酸序列1-901-914/2-515-530、3-91-123、2-613-654相应的三段合成多肽为抗原、研制出一种检测抗-HEVIgG的ELISA试剂。以该试剂检测中国、缅甸、印度和前苏联肠道传播非乙型肝炎(ET-NANBH)病人血清105份,仅3份中国病人血清阴性,阳性率为97.1%;检查实验感染HEVL赤猩猩血清,感染前阴性,感染后阳性;检查正常人血清99  相似文献   

5.
将含有α1肾上腺素受体三种亚型的全长cDNA质粒分别转染到人胚肾脏细胞(HEK293),α1A-,α1B-和α1D-AR在HEK293细胞株上得到高水平稳定表达,用^3H-inositol标记和柱层析法测定细胞磷酸肌醇积。观察在去甲肾上腺素长期作用下α1三种受体亚型介导磷酸肌醇蓄积敏感性降低的差别。  相似文献   

6.
本实验用人重组r-干扰素(rhu-IFN)作用HEP-2细胞后HLA-DR抗原和增殖细胞核抗原(PCNA)表达的检测来探讨r-干扰素对HEP-2细胞HLA-DR抗原表达诱导作用及体外抗增殖活性。用单克隆抗体CR3/43(抗HLA-DR)和Ki-67(抗PCNA)。以链霉素一生物素技术(LSAB)检测HEP-2细胞HLA-DR抗原和PCNA表达,结果显示:r-IEN诱导HLA-DR抗原和抑制PCNA表达其强弱与r-IFN剂量有关。资料提示:r-IFN不仅对HEP-2细胞有细胞毒作用,同时能调节其细胞膜特性,因而在喉癌的治疗中是有效的。  相似文献   

7.
含有Epstein-Barr病毒膜抗原的重组表达质粒及其基因免疫   总被引:1,自引:0,他引:1  
将Epstein-Bar(EB)病毒主要的膜抗原(MA)BLLF1基因片段插入pHD101-3质粒的CMV启动子下游,构建了真核表达质粒pHD-gp350,并转染293细胞进行瞬间表达。用免疫荧光法从细胞膜检测到表达的抗原能与其单克隆抗体发生特异性结合,Western-blot法证实,表达的抗原分子量为350kD.用能在真核细胞表达的重组质粒pHD-gp350的DNA,经Sepharose2B柱纯化后,注射经普鲁卡因预处理的Balb/C小鼠的四头肌,观察到EBV-IgA/MA抗体水平比EBV-IgG/MA低,而EBV-IgA/MA的持续时间比EBV-IgG/MA长。采用表达EBVMA的质粒DNA与CHO细胞表达的MA蛋白免疫小鼠,均获得抗EBVMA的抗体。  相似文献   

8.
利用EB病毒转化可产生较高水平人IgG和特异性抗2型登革病毒人抗体的Hu-TLC-SCID小鼠脾细胞,通过免疫组化、免疫荧光和PCR法检测转化细胞的人B细胞表面标志、EB病毒抗原和EB病毒基因。结果表明,被转化的Hu-TLC-SCID小鼠脾细胞能继续产生抗2型登革病毒的特异性人抗体,并具有人B细胞的、SmIgG标志及EB病毒潜伏膜蛋白-1(LMP-1)基因,可表达LMP-1和EB病毒核抗原(EBNA)。  相似文献   

9.
将含有鸡传染性支气管炎病毒 S1 基因c D N A 的重组转移质粒p S X I V V I+ X3 S1 . Holte 和p S X I V V I+ X3/4 S1 . Holte 分别与粉纹夜蛾核型多角体病毒 Tn N P V S V I- G D N A( O C C- ,gal+ ) 共转染草地夜蛾( Sf9) 细胞,经空斑纯化得到重组病毒 Tn N P V( X3) S1 . Holte O C C+ 和 Tn N P V( X3/4) S1 . Holte O C C+ 。将重组毒株分别感染 Tn5 B1 细胞,并进行 S D S P A G E 与 Westernblot 检测。结果表明, Tn N P V( X3/4) S1 . Holte O C C+ 在感染的细胞中高效表达了 S1 蛋白, S D S P A G E 凝胶薄层色谱分析结果显示,感染病毒后72 h S1 蛋白的表达量占细胞内总蛋白量的35 .8 % ,而 Tn N P V( X3) S1 . Holte O C C+ 感染的细胞内检测不出 S1 蛋白。经分析认为这一差异主要来自 S1 基因翻译起始位点及其附近的周围环境。  相似文献   

10.
神经肽Y可减轻大鼠血管α1肾上腺素受体亚型的脱敏作用   总被引:2,自引:0,他引:2  
董尔丹  陈明哲 《生理学报》1994,46(4):355-360
以离体大鼠主动脉与肾动脉对去甲肾上腺素(NE)的收缩反应分别代表α1B与α1A亚型肾上腺素受体(AR)激动时的生物学效应。血管经NE10μmol/L温育2h后,α1-AR介导收缩效应的敏感性显著降低,其中α1B亚型AR的脱敏程度显著大于α1A亚型AR。上述经NE温育的血管,在神经肽Y(NPY)0.5μmol/L存在时,α1B亚型AR的脱敏程度显著减轻。NE收缩主动脉的两时相分析表明,脱敏时主要表现为相性收缩时间延长,收缩幅度降低,而紧张性收缩并无显著改变;在NPY存在时上述相性收缩改变消失。提示α1B亚型AR脱敏的机制主要与细胞内Ca2+动员减慢减少有关。  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.
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.
16.
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   

17.
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   

18.
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   

19.
目的 针对医疗机构的合理用药水平进行评价研究。方法 根据医疗机构合理用药的具体要求,构建医疗机构合理用药评价指标体系,采用基于模糊群决策的方法和多指标评价分析法构建医疗机构合理用药评价模型。结果 构建了基于模糊群决策的医疗机构合理用药评价模型,并通过实例分析证明了评价模型的可行性。结论 建立的基于模糊群决策的医疗机构合理用药评价模型能够对医疗机构的合理用药水平进行科学评价,为提高医疗机构合理用药水平奠定基础。  相似文献   

20.
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   

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