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1.
青蒿毛状根合成青蒿素的培养条件研究   总被引:14,自引:0,他引:14  
对影响青蒿(ArtemisiaannuaL.)毛状根生长及青蒿素合成的培养条件进行了研究,确定最适的培养条件为:初始pH5.8~6.0,摇瓶转速130~150r/min,摇瓶装液量体积分数为25%,光照周期为16h/d,温度为30℃。在此条件下,经过25d培养获得青蒿素产量为223.3mg/L。  相似文献   

2.
发根土壤杆菌对葛属药用植物的遗传转化   总被引:10,自引:0,他引:10  
葛根是传统中药。利用发根土壤杆菌(Agrobacterium rhizogenes (Riker et al.)Conn)R1601转化野葛(Pueraria lobata(Willd.)Ohwi)、山葛(P.lobata var.montana)和三裂叶野葛(P.phaseoloides(Roxb.)Benth.)离体叶片,在叶片表面直接形成毛状根。毛状根的诱导频率分别为16.6%、16.2%和  相似文献   

3.
海马神经元乙酰胆碱激活通道在不同培养期的功能特性   总被引:1,自引:0,他引:1  
邹飞  陈培熹 《生理学报》1994,46(6):521-528
用膜片箝技术对不同培养期的新生大鼠海马神经元上乙酰胆碱受体单通道特性进行了研究,结果表明不同培养期ACh激活通道的电学特性不同。培养早期(1-2d),20ps通道占优势,开放以单个短开放事件为主,平均开放时间小于2ms.培养后期(18-21d)31,pS通道为主,开放随膜片的不同可分成两类,即单个短开放(时间常数为0.35ms和1.29ms)和簇状开放(时间常数为1.15ms和9.6ms),同时也  相似文献   

4.
将两株1型犬腺病毒(Canine adenovirus type 1,CAdl)DNA片段(29 ̄40m.u.)和两株2型犬腺病毒(CAd2)DNA片段(28 ̄44m.u.),分别克隆到质粒pBluescript SK中。经核苷酸序列测定和计算机分析表明,在上述克隆片段内,两株CAdl(CLL和Glaxo)的序列相同,两株CAd2(Toronto和China)的序列也相同;CAd1与CAd2具有9  相似文献   

5.
高活力纤维素酶菌株康氏木霉B—7的选育与产酶条件的研究   总被引:14,自引:0,他引:14  
王景林  尹清强 《生物技术》1996,6(6):14-17,20
野生型康氏木霉854-B_2分别经物理化学诱变因子,TDP辐射器和空间微重力辐射等因素的多级处理,得到1株形态发生明显改变的变异株B—7,其固体培养物的纤维素酶各组分酶活力,如滤纸糖酶活力(FPA)为34u/g,羧甲基纤维素酶活力(CMC—ase)为29.0u/g,β-葡萄糖苷酶活力(β-Glase)为29.0u/g,与854-β2相比,分别提高5.9倍,7.6倍和4.2倍。其固体培养的最佳条件是:pH6.0,28~30℃,96小时,最适培养基成分为:青草粉:麸皮=7:3,1.5~2.0倍水和(NH4)2SO41.5~2.0%(均以固体料计)。  相似文献   

6.
三裂叶野葛毛状根的诱导及其固体培养和液体培养   总被引:5,自引:1,他引:5  
发根农杆菌(Agrobacterium rhizogenes)ATCC15834感染三裂叶野葛(Pueraria phaseoloides)叶片外植体20 d后产生毛状根,毛状根可直接从叶片外植体叶脉处或从叶脉处产生的愈伤组织上产生。感染35d后,约85%的叶片外植体产生毛状根。毛状根能在无外源生长调节剂的 MS固体和液体培养基上自主生长。PCR扩增结果表明,发根农杆菌Ri质粒的rolBrolC基因已在三裂叶野葛毛状根基因组中整合并得到表达。与固体培养的毛状根相比,在液体培养基中培养的毛状根不仅生长迅速,也不会形成愈伤组织。在无外源生长调节剂的液体MS培养基中培养15d的三裂叶野葛毛状根的鲜重、干重、可溶性总糖含量及细胞内活性氧(ROS)含量分别为固体培养毛状根的1.59倍、1.18倍、5.25倍和1.16倍。  相似文献   

7.
露水草毛状根的诱导和培养   总被引:6,自引:0,他引:6  
发根农杆菌(Agrobacteriumrhizog6nes)pRi15834菌株感染露水草(Cyanotisarachnoidea)的茎和根的外植体及小苗,均诱导出毛状根。毛状很能在不含激素的MS培养基上生长。用纸电泳和高效薄层层析法,在毛状根中检测到甘露碱。用Southern印迹杂交,在植物DNA中检测到role基因。表明Ri质粒的T—DNA部分已转移到毛状根细胞的DNA中。该毛状根能产生β-蜕皮激素。露水草毛状根的诱导培养在单子叶植物中是一个成功的先例。  相似文献   

8.
抗寒锻炼对冬小麦幼苗质膜Ca^2+—ATPase的稳定作用   总被引:14,自引:0,他引:14  
王红  卢存福 《Acta Botanica Sinica》1998,40(12):1098-1101
通过氯化铈(CeCl3)沉淀的电镜细胞化学方法,观察了抗寒锻炼对冬小麦(TriticumaestivumL.)幼苗质膜Ca2+ATPase的稳定作用,主要结果是:(1)正常温度(20℃)下生长的冬小麦幼苗(未经抗寒锻炼),其质膜上有很强的Ca2+ATPase活性反应;当经过-9℃3h的低温处理后,质膜的Ca2+ATPase活性明显降低;在处理12h后,质膜的Ca2+ATPase活性进一步降低;当处理时间延长到24h,质膜的Ca2+ATPase完全失活,同时细胞的超微结构受到破坏。(2)冬小麦幼苗在2℃低温下锻炼15d后,其质膜的Ca2+ATPase活性高于未经抗寒锻炼的小麦幼苗。抗寒锻炼后的小麦幼苗在-9℃处理3h后,质膜的Ca2+ATPase活性与低温处理前相比无明显降低;经低温处理12h,质膜仍保持较高的Ca2+ATPase活性,较同样低温处理(-9℃,12h)但未经抗寒锻炼的幼苗高;当-9℃低温处理24h后,质膜上仍可观察到Ca2+ATPase的活性反应,而且细胞的超微结构也未受到破坏。结果表明,抗寒锻炼可提高冬小麦幼苗质膜Ca2+ATPase在低温下的稳定性  相似文献   

9.
绿僵菌在土壤中的延续及控制桃小食心虫的潜力   总被引:15,自引:3,他引:15  
研究了金龟子绿僵茵(Metarhiziumanisopliae)在土壤中的发育过程、数量消长及控制桃小食心虫的潜力.结果表明,接种62~82d后所有处理的CFU均降低80%以上,121~234d后降低99%以上.在灭菌和不灭菌土壤中,分生孢子初始接种量的半衰期分别为28.5d和23.8d,干菌丝粉分别为26.9d和19.6d.在土壤接种后100d,将桃小食心虫冬茧接入土壤,冬茧被侵染产孢后补偿了带菌量的下降,278dCFU比不接冬茧土壤第271d的带菌量大1000倍.在土壤接种后,不同时间接入土壤的冬茧死亡率直到第131d还保持在90%以上,但到第237d降至9.3%.未用绿僵菌处理的土壤中接入的桃小食心虫冬茧无死亡发生.小区试验中,在15、22.5、30和37.5kg·hm(-2)分生抱孢制剂剂量下死亡率达97.0~100%,而蛀果率仅为2.7~5.0%.在陕北进行了大田试验面积达670hm2,剂量为22.5kg·hm(-2)分生孢子制剂.蛀果率降至2.4%,未处理果园则高达30%.  相似文献   

10.
红豆杉细胞培养的研究   总被引:28,自引:1,他引:27  
从红豆杉(Taxuschinensis(Pilg)Rehd)的嫩茎及针叶诱导的出愈伤组织,对愈伤组织培养及细胞悬浮培养进行了研究,利用HPLC方法测定它们合成紫杉醇的能力,发现了能够提高培养细胞生长速率及紫杉醇含量的一些因子,红豆杉愈伤组织及悬浮培养细胞的生长速率已分别达到0.25g/L.d和0.28g/L.d。而他们的紫杉醇含量分别是0.0026%和0.012%。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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