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1.
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   

2.
目的:本文研究低能量氦氖激光照射荷瘤小鼠,观察对荷瘤T淋巴细胞增殖反应的影响。结果:BALB/C雄性小鼠腹腔接种S180接种后,进行激光照射小鼠内眼角,测定正常对照组、肿瘤对照组和7.33、11.00、14.67、22.00J/cm^2和29.33J/cm^2五个剂量激光照射组小鼠的T淋巴细胞增殖反应,结果表明11.00J/cm^2、14.67J/cm^2、22.00J/cm^2剂量的氦氖激光照射  相似文献   

3.
目的:He-Ne激光照射治疗的机理不明,激光照射引起细胞内Ca^2+水平变化,为治疗机理提供理论依据。方法:He-Ne激光照射引起鼠成纤维细胞L929内[Ca^2+]i的变化,用HO342对细胞DNA活性染色,Fluo-3AM对细胞内Ca^2+染色,利用FCM同时定量分析细胞DNA和细胞内Ca^2+的变化。结果:激光照射15min(光剂量11.81J/cm^2后,FCM分析可见DNA分布直方图右移  相似文献   

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目的:观察应用Nd:YAG激光,消除人工晶体植入术后,影响视力的后囊膜皱褶之效果。方法:国产JYZ-1A型YAG激光眼科治疗机。用单脉冲能量0.35mJ-1.5mJ,治疗总能量11.2mJ64.5mJ击射晶体后囊膜皱褶深处,形成34mm孔径管亮区。  相似文献   

5.
本文通过低强度He-Ne激光以能量密度分别为14.31J/cm^2(辐照5’)、28.62J/cm^2(辐照10)、57.24J/cm^2(辐照20)114.52J/cm^2(辐照40)燠夫体外周血后,检测其淋染色畸变率(CA),激光照射血样(能量密度由低到高)未照射血样CA分别平均为4.29‰、3.96‰、3.81‰、3.590‰、4.19‰、X^检测无显著差异,说明低强度的He-Ne激光辐照人  相似文献   

6.
He-Ne和CO2激光对茶树花药培养的药裂率和出愈率的影响,既有促进作用,也有抑制作用。按出愈率和愈伤组织生长状况的序列:He-Ne:20J/cm^2〉CK〉He-Ne:30J/cm^2〉CO2:35.4J/cm^2。对He-Ne激光照射花药及其愈伤组织的过氧化物酶同工酶分析,主要表现在弱酶带的变化上,无规律差异。  相似文献   

7.
CuBr激光对造血细胞增殖的影响   总被引:4,自引:1,他引:3  
本文介绍了CuBr激光的功率和照射时间对造血细胞增殖作用的影响,有利于对激光刺激造血细胞增殖机制的认识。造血细胞由BALB/c鼠的骨髓和胎肝制备而成。在低功率(20mW/cm2)578.2nm激光照射100秒时,使胎肝造血细胞增殖6.5倍,随照射时间增长,增殖效率将趋向饱和,并略有下降;在定时120秒照射时,随510.6nm的激光照射功率增大,激光对骨髓造血细胞的增殖作用变为抑制作用。  相似文献   

8.
不同波长激光辐照花生种子的生物学效应   总被引:9,自引:0,他引:9  
本实验考察了K+r、Ar+、Nd:YAG、HeNe和LD等不同波长的激光辐照对花生种子产生的生物学效应。结果显示,适当剂量不同波长的激光辐照都能促进花生种子生长。在辐照剂量为0.128w/cm2×180s的条件下,较短波长激光对花生幼苗的促进作用比长波长激光显著;在辐照剂量为1.28w/cm2×18s的条件下,短波长激光对花生种子的萌发及胚的生长有抑制作用,而长波长激光有促进效应。在相同辐照剂量条件下,不同功率密度与时间的组合其辐照效果不同。1.28w/cm2功率密度的Nd:YAG(532nm)激光脉冲输出辐照对花生种子的生长产生显著的抑制作用。实验结果提示,要得到相同的辐照效果,长波长激光与短波长激光相比,必须提高辐照功率密度或加大辐照输出剂量。  相似文献   

9.
目的:研究He-Ne激光照射鼠巨噬细胞对线粒体跨膜电势的影响,及其与激光剂量的关系。方法:用亲脂性阳离子荧光染料Rhodamine123对鼠巨噬细胞线粒体作荧光标记,以不同的激光剂量照射,采用图像分析系统(IAS)和荧光显微镜观察线粒体跨膜电势荧光强度的变化。结果:低功率He-Ne激光照射5,10,15min,激光剂量分别为0.649,1.388和2.082J/cm^2,巨噬细胞线粒体跨膜电势荧光  相似文献   

10.
在共培养体系中单克隆抗体AH6对小鼠胚泡着床的影响   总被引:6,自引:0,他引:6  
王晓琦  朱正美 《动物学报》1998,44(4):443-449
以单克隆抗体AH6「特异结合Le^Y寡糖,Fuca1-2Galβ1-4(F痉-3)GlcNAc-」以及其它3种与Le^Y寡糖结构近似的寡糖特异结构的单克隆抗体aLe^a、aLe^b和FE-A5为工具,采用小鼠体外着床模型。研究细胞表面Le^Y寡糖抗原与着床的关系及其在着床过程中具体作用环节。  相似文献   

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14.
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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16.
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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