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1.
王文采 《植物研究》2017,37(5):641-644
描述了自重庆市江津区四面山发现的荨麻科赤车属一新种和楼梯草属二新种:(1)四面山赤车,与融安赤车近缘,区别在于新种的叶的二级脉较少,2枚雌花被片有短角状突起,以及长圆形瘦果;(2)稀柱毛楼梯草,可能与托叶楼梯草近缘,区别在于新种的叶较小,雌总苞苞片,以及雄、雌小苞片均在背面具龙骨状突起,柱头由只3~4根毛组成;(3)四面山楼梯草,与长尖楼梯草近缘,区别在于新种茎的顶端被短柔毛,雄头状花序的花序梗较短,以及雄总苞苞片呈条状船形,背面具龙骨状突起。  相似文献   

2.
王文采 《广西植物》2016,36(1):1-29
(1)根据该文中赤车属与楼梯草属各种形态学的区别,认为赤车属较为原始,在楼梯草属之前自冷水花属衍生而出。(2)将赤车属划分为5组;将C.B.Robinson描述的Elatostemoides属降为组级群,作为赤车属中接近原始群全缘赤车组sect.Pileoides的一个组处理,此外还描述了一个与sect.Elatostemoides近缘的1新组,羽脉赤车组sect.Leiolaena,并根据叶、叶的脉序、雌花序、雌花被片和瘦果等器官的演化趋势给出显示赤车属属下诸群间亲缘关系的系统发育树。(3)对中国赤车属的属下分类群进行了修订,共承认32种1亚种7变种,给出检索表、描述及多幅插图,并将它们划分为4组、2亚组和9系,其中除sect.Leiolaena之外,还新描述了2亚组、5系、2种和3变种;在2003年被归并为同物异名的长柄赤车、曲毛赤车、波缘赤车、小赤车和富宁赤车的种级地位得到恢复。此外,还写出了中国赤车属的分类学简史和地理分布。  相似文献   

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描述了自重庆市江津区四面山发现的荨麻科赤车属一新种和楼梯草属二新种:(1)四面山赤车,与融安赤车近缘,区别在于新种的叶的二级脉较少,2枚雌花被片有短角状突起,以及长圆形瘦果;(2)稀柱毛楼梯草,可能与托叶楼梯草近缘,区别在于新种的叶较小,雌总苞苞片,以及雄、雌小苞片均在背面具龙骨状突起,柱头由只3~4根毛组成;(3)四面山楼梯草,与长尖楼梯草近缘,区别在于新种茎的顶端被短柔毛,雄头状花序的花序梗较短,以及雄总苞苞片呈条状船形,背面具龙骨状突起。  相似文献   

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报道了7个楼梯草属和赤车属植物(荨麻科)新纪录,它们分别为锐齿楼梯草(E. cyrtandrifolium),变黄楼梯草(E. xanthophyllum),对叶楼梯草(E. sinense),宽叶楼梯草(E. platyphyllum),托叶楼梯草(E. nasutum),短叶赤车(P. brevifolia)和华南赤车(P. grijsii)。列出了各个物种的标本引证和地理分布情况。  相似文献   

5.
赤车属(荨麻科)四种植物的订正   总被引:1,自引:0,他引:1  
根据对赤车属植物标本的研究,将小赤车归并入短叶赤车,小异被赤车归并入异被赤车,海南赤车归并入滇南赤车,长茎赤车归并入赤车。  相似文献   

6.
楼梯草属研究随记   总被引:2,自引:1,他引:1  
王文采 《广西植物》2010,30(6):713-727
在该文中首次给出革叶楼梯草的雄头状花序描述;还给出樱叶楼梯草雄头状花序的修正描述和兜苞墨脱楼梯草的修正特征集要;写出托叶楼梯草和南川楼梯草二种的分类学修订,其中包括2新变种和2新等级;描述了小叶楼梯草组的1新种和骤尖楼梯草组的3新种;数年前被归并为异名的兜苞墨脱楼梯草和五肋楼梯草得到恢复。  相似文献   

7.
王文采 《广西植物》2016,36(Z1):120-134
在该文中首次给出革叶楼梯草的雄头状花序描述; 还给出樱叶楼梯草雄头状花序的修正描述和兜苞墨脱楼梯草的修正特征集要; 写出托叶楼梯草和南川楼梯草二种的分类学修订,其中包括2新变种和2新等级; 描述了小叶楼梯草组的1新种和骤尖楼梯草组的3新种; 数年前被归并为异名的兜苞墨脱楼梯草和五肋楼梯草得到恢复。  相似文献   

8.
王文采 《广西植物》2016,36(Z1):171-173
头序赤车的特征在于其具花序托和总苞的雌头状花序,根据此一特征即可将它与赤车属的其它所有种区别开。因此,在2002年被错误归并为异名的此赤车属进化种,以及根据其建立的单种进化组头序赤车组在该文中予以恢复。  相似文献   

9.
头序赤车的特征在于其具花序托和总苞的雌头状花序,根据此一特征即可将它与赤车属的其它所有种区别开.因此,在2002年被错误归并为异名的此赤车属进化种,以及根据其建立的单种进化组头序赤车组在该文中予以恢复.  相似文献   

10.
王文采 《广西植物》2016,36(Z1):148-151
描述了荨麻科楼梯草属2新种,其中发现自贵州的安龙楼梯草与条叶楼梯草近缘,与后者的区别在于此新种的茎和叶无毛,叶片椭圆形或狭倒卵形,较宽,雄苞片无角状突起,雌头状花序无梗,其花序托不等3~4裂,柱头画笔头状; 自广西发现的厚序楼梯草与福贡楼梯草近缘,与后者的区别在于此新种的叶片质地较薄,呈膜质,上面疏被糙伏毛,叶柄较短,长达2 mm或不存在,雄花序梗圆柱形,较长,密被短柔毛,雄总苞由一层不具角状突起的苞片组成。  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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