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1.
分支系统学简评   总被引:1,自引:0,他引:1  
冷琴  周巍 《古生物学报》1997,36(1):122-131
分支系统学简评冷琴(中国科学院南京地质古生物研究所,南京210008)周巍(南京市玄武区花园路,南京210037)1前言分支(支序)系统学(Cladistics,Cladisticsystematics),又称系统发育分类学(phylogenetic...  相似文献   

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盐生隐杆藻胞外多糖含量的影响因子   总被引:1,自引:0,他引:1  
盐生隐杆藻胞外多糖含量的影响因子欧瑜刘志礼(南京农业大学理学院生化室,南京210095)(南京大学生物科学与技术系,南京210093)SeveralfactorsinfluencingexopolysaccharidecontentsofAphano...  相似文献   

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棒毛荠属属名的考证及其属模式学名的订正陆莲立(江苏省植物研究所,南京210014)(中国科学院植物研究所,南京210014)TheidcntificationandrevisiononthegenusCochleariopsisY.H.Zhangan...  相似文献   

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杨树护田林带疏透度模型及应用   总被引:3,自引:0,他引:3  
杨树护田林带疏透度模型及应用张纪林,吕祥生(江苏省林业科学研究所,南京211153)(江苏省农林厅林业局,南京211153)PorosityModelofPoplarFarmlandShelterbeltandItsApplication¥ZhangJilin(Forestryscienceandtech-nologyresearchInstituteofJiangsu),LuXiangsheng(ForestryBureau“ofJiangsuProvince).ChineseJournalofEcology,1993,12(5):56-60。Inthisarticle,theauthorsatfirstmadethree-principledselection,partialcorrelation,bestmulti-prin-cipleregressionselectloninsequence,Secondlyonthebasisofresidualanalysis,theauthorsmadetestofhighleveragecase,influencecaseandoutlieronsample  相似文献   

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作物对太阳紫外线辐射增加的生物效应及其评估   总被引:43,自引:3,他引:43  
作物对太阳紫外线辐射增加的生物效应及其评估郑有飞,杨志敏,颜景义,万长建(南京气象学院,南京210044)Biologicalresponseofcropsonenhancedsolarultravioletradiationanditsestima...  相似文献   

6.
心叶留兰香的挥发油成分   总被引:2,自引:0,他引:2  
心叶留兰香的挥发油成分周自新, 桂新(南京市卫生防疫站,南京210003)(安徽中医学院中药系,合肥230038)Thechemicalcomponentsintheessentialoilsfrommenthacordifolia¥ZhouZi-X?..  相似文献   

7.
杂种鹅掌楸叶解剖结构特征的识别   总被引:5,自引:0,他引:5  
杂种鹅掌楸叶解剖结构特征的识别叶金山周守标王章荣(南京林业大学森林资源与环境学院,南京210037)DiscriminationofleafanatomicstructureoftheChinesetuliptreehybridsYeJinSha...  相似文献   

8.
工业固体废弃物的急性生物毒性研究   总被引:7,自引:0,他引:7  
工业固体废弃物的急性生物毒性研究谢思琴,顾宗濂,周德智(中国科学院南京土壤研究所,南京210008)Acutebiotoxicityofindustrialsolidwastes¥.XieSiqin;GuZonglianandZhouDezhi(In...  相似文献   

9.
射干和鸢尾的挥发性成分   总被引:6,自引:0,他引:6  
射干和鸢尾的挥发性成分秦民坚王强徐珞珊徐国钧(中国药科大学,南京210038)田中俊弘(岐阜药科大学,日本国岐阜市502)VolatileconstituentsofBelamcandachinensisandIristectorumQinMinJ...  相似文献   

10.
一种非基因效应的遗传机制   总被引:1,自引:0,他引:1  
祝其昌ZHU  Qi-Chang 《遗传》1997,19(1):37-40
一种非基因效应的遗传机制祝其昌(江苏省农业科学院经济作物研究所,南京210014)ANongenicHereditaryMechanismZhuQichang(InstituteofEconomicCrops,JiangsuAcademyofAgri...  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   

18.
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   

19.
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   

20.
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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