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1.
山东假蹄盖蕨属两新种   总被引:1,自引:0,他引:1  
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湖南蹄盖蕨科二新种   总被引:1,自引:0,他引:1  
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湖南省假蹄盖蕨属一新种吴世福(上海技术师范学院生物系上海201418)关键词湖南省;假蹄盖蕨属;狭叶假蹄盖蕨ANEWSPECIESOFATHYRIOPSISFROMHUNAN¥WuShifu(DepartmentofBiology,ShanghaiT...  相似文献   

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对直立介蕨Dryoathyrium erectum (Z. R. Wang) W. M. Chu &; Z. R. Wang与介蕨属Dryoathyrium、假蹄盖蕨属Athyriopsis的叶、毛、孢子囊群和孢子的形态进行了比较研究。直立介蕨叶轴和羽轴上的沟槽不明显、具有单列细胞的节状毛、孢子囊群有双生一脉, 以及孢子的形态等特征与假蹄盖蕨属植物相似。结合叶绿体DNA trnL-F区序列分析结果, 所有形态及分子资料均表明该种植物应属于假蹄盖蕨属, 应恢复其原名直立假蹄盖蕨Athyriopsis erectum Z. R. Wang。  相似文献   

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山东假蹄盖蕨属植物孢子形态研究   总被引:3,自引:1,他引:2  
李建秀  丁作超 《植物研究》1989,9(3):105-112
本文采用了光学显微镜和扫描电子显微镜对山东分布的4种假蹄盖蕨(其中鲁山假蹄盖蕨Athyriopsis lushanensis J.X.Li,sp.nov.和山东假蹄盖蕨A.sh-andongensi,J.X.Li et Z.C.Ding,sp.nov.为新种[1],中日假蹄盖蕨A.kiusianum(Koidz.)Ching为我国新记录)孢子形态进行了系统的观察,其孢子周壁纹饰在种间有着显著的差异,为其种间分类提供了孢粉学的依据。  相似文献   

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中国蹄盖蕨属三新种   总被引:1,自引:0,他引:1  
碧江蹄盖蕨新种图1 Athyrium bijiangense Y. T. Hsieh et W. M. Chu, sp. nov. Species proxime affinis A. christensenii Tard. Blot, a quo differt lamina frondis oblongo-lanceolata, pinnulis ca. 1cm longis, ca. 4mm latis, apice obtusis et aristato-serratis non rotundo-truncatis et integris, soris costulae propioribus. Tota planta ca. 55cm alta; rhizoma erectum, cum basibus stipitis paleis atro-fuscibus linearibus dense obtectum; frondes caespitosae;  相似文献   

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采用光镜和扫描电镜对山东分布的蹄盖蕨科2属(蹄盖蕨属和假蹄盖蕨属)7种植物的根、根茎、叶柄、叶轴、叶表皮、表皮毛和孢子囊进行了形态解剖学的系统研究.结果表明,在形态解剖学方面2属植物的共同特征为:根均为无髓中柱;叶柄基部的双柱型维管束向上渐靠近联合形成1个周韧型维管束;叶上下表皮垂周壁均呈波状;气孔主要为胞环型、周胞型或极附型.2属植物的不同特征是:蹄盖蕨属植物体无毛;而假蹄盖蕨属植物叶片和叶轴上均生有腺毛;蹄盖蕨属植物根皮层外侧为薄壁细胞,假蹄盖蕨属则为棕色厚壁细胞环.研究结果表明蹄盖蕨科为一个自然分类群,并支持假蹄盖蕨属的成立.  相似文献   

8.
利用光学显微镜详细观察蹄盖蕨科(Athyriaceae)2属4种植物,即蹄盖蕨属的尖头蹄盖蕨(Athyrium vidalii)、长柄蹄盖蕨(A.longius)和喜马拉雅蹄盖蕨(A.fimbriatum)以及亮毛蕨属的亮毛蕨(Acystopteris japonica)配子体发育过程,记录配子体各发育阶段的特征。4种植物的孢子都为单裂缝,两侧对称,孢子萌发类型为向心型,配子体发育类型为铁线蕨型,性器官都为薄囊蕨型,成熟原叶体为对称的心脏形,无毛状体;种间差异包括孢子纹饰、孢子萌发时间、配子体形成时间、丝状体长度、片状体和原叶体的形态以及性器官大小。  相似文献   

9.
张宪春 《植物研究》1991,11(3):1-15
作者对国产蹄盖蕨属软刺蹄盖蕨组植物从形态分类和地理分布上进行了研究,共计载了23种。其中Athyrium densisorum,A.medogenseA.chingianum为新种,A.paranigripes为一新名称。文中还附有分类检索表,每种都有文献、异名和标本引证及地理分布。  相似文献   

10.
报道了蹄盖蕨属耳蕨状蹄盖蕨组植物2系8种;有分种检索表、文献引证、标本引证以及本组植物的分布。  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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