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1.
脱落酸高产菌的激光诱变效应研究   总被引:8,自引:1,他引:7  
本实验对比紫外、 He Ne 激光、 Nd: Y A G 倍频脉冲激光对脱落酸产生菌的诱变效果。紫外诱变正变率为 384% ,负变率 769% ; He Ne 激光诱变正变率为 56% ; Nd: Y A G 倍频脉冲激光诱变正变率为196% 。 Nd: Y A G 倍频脉冲激光诱变辐照次数在 400 次时效果较好,所得高产株效价提高率可达 60% 以上  相似文献   

2.
倍频Nd:YAG激光对钝项螺旋藻的诱变效应   总被引:3,自引:0,他引:3  
利用倍频Nd:YAG激光(波长532nm,功率500mW,功率密度160mW/cm^2)诱变钝项螺旋藻,辐照时间为15min、10min、5min通过测定藻丝形态参数、叶绿素α、β-胡萝卜素、生长速度,比较倍频Nd:YAG激光对钝项螺旋藻生长的影响。实验结果表明:与出发株相比,经倍频Nd:YAG激光辐照后,藻丝形态发生变化,藻丝长、螺旋数、螺旋长变小;15min,10min辐照组出现螺旋变松驰;1  相似文献   

3.
激光微束与光钳系统周志康(重庆京渝激光生物研究所重庆400039)本文报导了由我所设计的激光微束与光钳系统的结构和特点。本系统由脉冲调Q倍频YAG激光和连续YAG倍频激光器组成,前者用于微束,后者用于光钳。微束的主要参数激光波长1.06um、0.53...  相似文献   

4.
我们对18例顽固性宫颈糜烂伴肥大病人采用YAG激光作锥形切除治疗,经1~10年随访,未见复发,效果满意,激光治疗顽固性宫颈糜烂行锥切优于传统手术切除。  相似文献   

5.
梁志芳  莫伟 《蛇志》1996,8(2):30-33
本组48例鼻腔及鼻窦血管瘤的治疗,其中用单纯硬化疗法3例,单用Nd;YAG激光治疗8例,冷冻治疗5例,手术加激光或冷冻加手术,手术切除后高频电或硝酸银烧灼残根32例进行分析,各具优点,讨论了各种鼻窦血管瘤的最佳疗法的选择。  相似文献   

6.
本文采用CO2激光和Nd:YAG激光对13例宫颈及宫颈粘膜下肌瘤进行了切除治疗,疗效满意。其中瘤体最大4cm,最小1cm均位于宫颈间质组织内和宫颈管内。术中除1例少许出血外,余例几乎无出血。术后无1例感染,伤口愈合好。经过临床观察,认为采用激光治疗,方法简便,不需缝合,不住院,宫颈无粘连狭窄,值得采用。  相似文献   

7.
QS激光治疗面部雀斑临床疗效观察   总被引:2,自引:0,他引:2  
用QSND YAG倍频532nm及QS翠绿宝石755nm波长激光一次治疗面部雀斑。研究:观察哪些波长组合及用何方法在临床应用既能达到美容效果、又能缩短疗程、节约费用。在将近选患者面部色素密度均匀部位分左、中、右区域进行治疗观察后,发现:(1)QS532nm治疗组6个月疗效达40.5%(P〈0.05),(2)QS755nm治疗组6个月疗效达12%(P〈0.05),(3)QS532nm+QS75nm治疗组疗效达72%(P〈0.01)。说明采用两种波长激光同时复合治疗疗效好,而且起到了美容效果,临床值得推广。  相似文献   

8.
通过DNA序列测定在一名46,XY女性反转患SRY基因启动子区发现了一个新的突变:nt-81G-A。该突变不见于正常男性,因此不是DNA多态性。为了检测这一点突变对SRY基因表达功能的影响,构建了分别由正常或突变的人SRY基因启动子区片段调控氯霉素乙酰转移酶报告基因表达的两个质粒,寡核苷酸探针杂交证实该启动子片段正常或携带有G-A突变。  相似文献   

9.
核因子Y(nuclearfactorY ,NF Y)也称作CBF(CCAATboxbindingfactor)、CP1 ,是结合CCAAT盒的转录因子。它能识别真核基因启动子区域的 5′ CTGATTGGYYRR 3′或 5′ YYRRCCAATCAG 3′共有序列。有功能的NF Y是一个异源三聚体蛋白 ,它包含三个不同的亚单位A、B、C。细胞衰老是由细胞分裂的次数决定的。控制细胞分裂的机制之一是调控G1 /S期的基因表达。当细胞衰老时 ,由于G1 /S基因调控的转变 ,细胞不能进入S期而只停留在G1期。NF Y正是通过与G1 /S…  相似文献   

10.
评《植物进化生物学》一书李林初(复旦大学生物系上海200433)AREVIEWABOUT“PLANTEVOLUTIONARYBIOLOGY”EDITEDBYCHENGJIAKUANANDYANGJI¥LiLinchu(DepartmentofBiol...  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.
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   

14.
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.
18.
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   

19.
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   

20.
Fluid collected from hatching eggs of Haemonchus contortus contained a lipase which hydrolysed 2-naphthyl laurate (about 0·7 μmol naphthol freed /h/106 eggs). The fluid also hydrolysed l-leucinamide (about 2·3 μmol leucine freed/h/106 eggs). The fluid when added to normal or heated eggs caused ‘hatching’. ‘Hatching’ also occurred in exsheathing fluid from infective juveniles and in a preparation of pancreatic lipase containing leucine aminopeptidase. A purified mammalian leucine aminopeptidase in combination with several different lipases did not attack egg shells.The ‘spontaneous’ hatching of eggs of H. contortus was strongly inhibited by 1,10-phenanthroline, 10?3M, and this inhibition was reversed by Zn2+. However, the inhibition of ‘hatching’ of eggs in externally applied hatching fluid, or the hydrolysis of leucinamide in hatching fluid was generally less marked.  相似文献   

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