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1.
粘附分子P选择素与疾病关系研究   总被引:2,自引:0,他引:2  
周同  李晓 《生命科学》1996,8(5):43-43,42
粘附分子P选择素与疾病关系研究周同,李晓,楼鼎秀,董德长(上海第二医科大学附属瑞金医院上海 200025)选择素(selectins)是新近被发现属细胞粘附分子一个家族。包括P选择素(P-selectin)、E选择素(E-selectin)和L选择素...  相似文献   

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IPEP索引资料库(6)QingLi,JunLing,andWang-yiLiu,Partialrestorationofinactivatedribosomeswithsodiumborohydrideoraminoacids,FEBSLett.(...  相似文献   

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从紫果西番莲(Pasifloraedulis)、杂交种西番莲(P.edulisXP.edulisvar.flavicarpa)、黄果西番莲(P.edulisvar.flavicarpa)、转心莲(P.caerulea)及龙珠果(P.foetida)分离到的5个黄瓜花叶病毒(CMV)分离物(PE、PE2、PEf、PC、PF)所作的生物学性质、理化特性和血清学关系的比较研究结果表明,5个分离物在寄主反应及血清学性质上存在不同,而在病毒粒体形态、体外抗性、蚜虫传毒和病毒外壳蛋白分子量方面无明显差异。根据5个分离物的寄主反应和血清学关系,可将其区分为CMV的两个亚组,其中PE、PE2、PC和PF属CMV亚组I,PEf属CMV亚组I。  相似文献   

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信号肽疏水性的提高促进青霉素G酰化酶分泌   总被引:9,自引:0,他引:9  
设计和合成了一段具有连续10仆亮氨酸强疏水核心的信号肽(artificial signal peptide,ASP),由EcoRI-KpnI位点融合到青霉素G酰化酶(penicillin Gacylase,PAC)信号肽(wild typesignal peptide,WTSP)的-4Pro位点,分别构建了PAC表达质粒:pKKpac△SP,pKKpacWTSP,pKKpacASP,pETpac  相似文献   

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PEG-mediatedGeneTransferintoOrychophragmusViolaceusCotyledonProtoplastandRegenerationofTransgenicPlantsZHOUJi-ming(周冀明),WEIZh...  相似文献   

6.
点状产气单胞菌脯氨酰内肽酶基因克隆与序列测定   总被引:2,自引:0,他引:2  
点状产气单胞菌点状亚种(Aeromonas puncata subsp.punctata)具有脯氨酰内肽酶(prolyl endopeptidase PEP)活性。将其染色体DNA有Eco RⅠ部分酶切后回收8-16kb的DNA片段,与EcoRⅠ消化载体pUC18连接后转化E.coil DH5α,用该酶的专一性底物Benzyloxycarbonyl-Gly-β-naphthylamide从质粒库中  相似文献   

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点状产气单胞菌脯氨酰内肽酶在大肠杆菌中的高效表达   总被引:1,自引:0,他引:1  
采用PCR分段克隆法将点状产气单胞菌点状亚种(Aeromonas puctata subsp.jpuctata)脯氨酰内肽酶(prolyl endopeptidase,apPEP)的编码区基因分成3段扩增并拼接成编码690个氨基酸的完整基因apPEP,将其克隆在表达载体pBL和pKKH上,构建成温度和IPTG诱导型高效表达apPEP的重组大肠杆菌BL21/pBL-PEP和BL21/pKKH-PEP  相似文献   

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本文报道了采自云南省地表枯枝落叶层的目 6新种,隶属6科6属,分别是褐带单烟Caeciliiusspadlcitaensis(单科Caeciliidae),褐痣塔 Tagalopsocus phaeostigmus(双科Amphipsocidae),双钩外 Ectopsocusbiunncialis(外科Ectopsocidae),中斑围 Peripsocusmedimacularis(围 科Peripsocidae),小头触 Psococerastiscapitulatis( 科Psocidae)及单钩苔鼠 Lichenomimahamata(鼠 科Myopsocidae)。模式标本保存于北京农业大学昆虫标本馆。文中量度单位为mm。  相似文献   

9.
水稻内生联合固氮细菌的筛选,鉴定及其分布特性   总被引:14,自引:0,他引:14  
利用乙炔还原法和固定15N2 活性测定法对分离自水稻( Oryza sativa L.)“越富”种子、根、茎和叶的内生细菌进行了筛选,获得29 株具有体外固氮能力的水稻内生联合固氮细菌。鉴定结果表明它们分属于根癌土壤杆菌( Agrobacterium tumefaciens (Smith et Townsend) Conn) ,放射土壤杆菌( A. radiobacter (Beijerinck et van Delden) Conn) ;阴沟肠杆菌( Enterobacter cloacae (Jordan) Hormaeche et Edwards) ,成团肠杆菌( E. agglomerans (Beijerinck) Ewing et Fife) ,坂崎肠杆菌( E. sakazakii Famer et al.) ;皮氏产碱菌( Alcaligenes piechaudii Kiredjian et al.) ,反硝化产碱菌( A. denitrificans (Leifson et Hugh) Ruger et Tan) ;类产碱假单胞菌( Pseudomonas pseudoalcaligenes Stanier) ,产碱假单胞菌( P. alcal  相似文献   

10.
细胞周期蛋白(cyclin)D在鼻咽癌中的表达及功能初?…   总被引:1,自引:0,他引:1  
探讨了细胞周期蛋白(cyclin)D在EB病毒(Epstein-Barr virus)潜伏膜蛋白1(latent membrane protein,LMP1)阳性和阴性表达的鼻咽癌细胞5系中的表达特征,利用流式细胞仪同时从DNA及蛋白质水平初步分析了cyclin D1在鼻咽癌细胞系中的功能。Western印迹的结果发现cyclinh D1在CNE-LMP1中过表达,在HNE1中表达较弱;Cycli  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   

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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