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1.
植物胚胎学实验方法(七)同时显示胚中贮藏的淀粉、蛋白质和脂类的永久制片法胡适宜(北京大学生物系,北京100871)METHODOFPREPARATIONOFSLIDESFORSIMULANEOUSDEMONSTRATIONSOFSTARCHGRAIN...  相似文献   

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用毛细管电泳技术检测DNA点突变   总被引:1,自引:0,他引:1  
毛细管电泳(CE)是90年代初发展起来的新技术,具有分辨率高、重现性好、灵敏度高、快速和易于实现自动化的特点。后来又发展了激光诱导荧光检测器(LIF),大大提高了分析灵敏度,对微量样品如单细胞分析等,具有很大的优势。通常,利用CE技术可以在20min内分析完成几千个碱基的DNA片段。CE可以应用于DNA点突变的检测,目前在PCR基础上利用CE技术对DNA已知点突变及未知点突变的检测发展十分迅速。1.已知点突变的检测1.1 扩增抗拒突变系统PCR(ARMSPCR)和短串联重复PCR(STRPCR)  ARMSPCR和S…  相似文献   

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1992年南宁地区应用抗寒剂CR-4进行水稻育秧的效果蓝蔚(南宁地区农业技术推广站,530001)EFFECTSOFUSINGTHECILD-RESISTERCR-4FORRICESEEDLINGCULTUREINNANNINGAREAIN1992¥...  相似文献   

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PCR扩增葡萄球菌肠毒素A全长基因方法的建立及意义   总被引:1,自引:1,他引:0  
为了分析和克隆葡萄球菌肠毒素(SE)A全长基因,设计了一对针对SEA全长基因的特异性引物,成功地用PCR反应从标准产SEA的葡萄球菌基因组中扩增出了一条约770bp的条带,为进一步用PCR法克隆SEA基因,并把它用于抗肿瘤研究奠定了实验基础  相似文献   

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通过对菜粉蝶颗粒体病毒粒子(样品)遥表面增强拉曼散射(SERS)光谱的分析,得出样品分子在SERS中与银表面相互作用的一些特征。样品分子主要通过闳基和氨基与银表面键联。相应谱带的拉曼增强效果与分子基因处于银表面的几何状态有关。分子与银表面产生化学吸附芳香族氨基酸侧链的π-电子得合物和分子基因的α-复合物的存在,使增强具有短程特性,其增强机制主要为分子增强。  相似文献   

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本文报道了胆红素和胆绿素,以及氧化胆红素的SERS谱图。通过对其谱图的分析发现,氧化胆红素SERS谱与胆绿素SEES谱极其相近。表明胆红素在碱性环境中可被氧化成胆绿素。另外,通过对比胆红素和胆绿素的SERSS谱,发现在银胶界面它们的吸附构象不同。  相似文献   

7.
马氏钳蝎毒素中多肽BmK4112的分离纯化和一级结?…   总被引:2,自引:0,他引:2  
对马氏钳蝎粗毒中多肽进行分离纯人级鉴定。应用凝胶过滤、离子交换和HPLC的反相色谱方法分离纯化样品。应用二疏基苏醇(DTT)还原,碘乙酸保护法对纯化样品进行修饰,修饰样品经酶解后应用Edrnan降解法,并结合ESI-MS法和串联质谱法(MS-MS)分析肽的序列。比较修饰前后的质谱,测定分子中的二硫链数目。分离纯化工获得多肽BmK4112,其一级结构为TPYPV NCKTD RDCVM CGLGI  相似文献   

8.
云南发现中华秋沙鸭和黑嘴鸥   总被引:1,自引:0,他引:1  
云南发现中华秋沙鸭和黑嘴鸥@杨岚@杨晓君¥中国科学院昆明动物研究所云南发现中华秋沙鸭和黑嘴鸥CHINESEMERGANSERANDSAUNDER′SGULLWATCHEDINYUNNAN,CHINA1997年1—3月在进行云南省高原湖泊的水禽调查过程中,于...  相似文献   

9.
不同光质所育稻苗对高温胁迫的反应   总被引:3,自引:0,他引:3  
不同光质所育稻苗对高温胁迫的反应毛金水,杨大旗(西南农业大学生物学基础部,重庆630716)THERESPONSESOFRICESEEDLINGSTOHIGHTEMPERATURESTRESSUNDERDIFFERENTLIGHTQUALITIES¥...  相似文献   

10.
为进一步研究HFRS免疫损伤机制,用ELISA法同步测定了108例不同临床型、不同病日、病期HFRS患者血清中特异性IgA、IgE抗体以及HFRS病毒特异性IgA、IgE型CIC的水平及检出率。发现HFRSIgA型抗体在轻型病例高于中、重型病例;HFRSIgE型抗体及IgE型CIC在重型病例高于中、轻型病例。上述差异在病程早期(发热、休克少尿期,或是3~8病日)尤为突出。IgA型CIC则未见到上述差异。  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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