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校订了我国商陆属植物,计有4种。Phytolac caclavigera W.W.Smith是多雄蕊商陆的异名,Ph.hunanensis Hand.-Mazz.和Ph.zhejiangensis W.T.Fan是日本商陆的异名。Ph.Esquirolii Lévl.不是本属植物,而是崖豆藤野桐Mallotus millietii Lévl.(大戟科). 相似文献
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道孚香茶菜的二萜成分 总被引:1,自引:0,他引:1
从河南省新县产道孚香茶莱[Rabdosia dawoensis(Hand. Mazz.)Hara]叶中分离到两个二萜化合物,根据各种光谱数据推断一个为新化合物,其化学结构为:对映-11α-羟基-3α,6β,7α-一三乙酰氧基-16-贝壳杉烯-15-酮,命名为道孚香茶菜甲素(dowoensin A),另一个为已知化合物信阳冬凌草甲素(xindongnin A). 相似文献
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紫草科(Boraginaceae)附地菜属(Trigonotis)的果实形态具有重要的分类学意义,是该属组级水平划分的重要依据.而该属之中的中国特有种富宁附地菜(T.funingensis)果实形态特征尚不清楚,其组级水平分类学地位的归属尚存疑问.野外考察在广西那坡采集到该种成熟果实,在解剖镜和扫描电镜下观察形态特征并... 相似文献
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南京中山植物园于20世纪50年代引种栽培了11株南方红豆杉〔Taxus chinensis(Pilg.)Rehd. var. mairei(Lemée et Lévl.)Cheng et L.K.Fu〕。45年后,在邻近的天然林中出现了含有400余个个体的自然种群。根据这一事实作者认为,如果整体生态条件具备,也就是在生物多样性和生境多样性都很丰富的自然生境中,迁地保护的小种群可以发展成较大种群,这将使迁地保护的作用与功能得到重大发展。从保护生物学原理出发,应认真关注迁地保护的生境条件。因此,迁地保护区的设计应予以改进,还应构建人工栽培园地与自然(野生)生境混合的区域,以创造自然种群发生的必要条件。 相似文献
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报道了秦岭种子植物区系4新记录属[杜若属(Pollia Thunb.)、美冠兰属(Eulophia R.Br.ex Lindl.)、常山属(Dichroa Lour.)和吊灯花属(Ceropegia Linn.)],8新记录种[川杜若Pollia miranda(Lévl.)Hara、长距美冠兰Eulophia dabia(D.Don)Hochr.、常山Dichroa febrifugaLour.、肉色土栾儿Apios carnea(Wall.)Benth.exBaker、柳叶蓬莱葛Gardneria lanceolata Rehd.et Wils.、显脉獐牙菜Swertia nervosa(G.Don)Wall.ex C.B.Clarke、皱果赤瓟Thladiantha henryi Hemsl.var.henryi和宝兴吊灯花Ceropegia paohsingensis Tsiang et P.T.Li]。 相似文献
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重阳木[Bischofia polycarps(Lévl.)Airy Shaw]为大戟科(Euphorbiaceas)重阳木属(Bischofia Bl.)落叶乔木,干形通直,常作行道树栽植;产秦岭和淮河流域以南各地,广东、广西北部和北部等地有引种[1]. 相似文献
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珍珠菜属四种植物的核型分析 总被引:2,自引:0,他引:2
对珍珠菜属4种植物的核型进行了研究。结果表明,叶头过路黄(Lysimachia phyllocephala Hand.-Mazz.)的核型为:2n=2x=24=2m 6sm 2st 14t,茂汶过路黄(L. stellarioidesHand.-Mazz.)的核型为:2n=2x=24=4m 2sm 18t,均属首次报道。矮桃(L. clethroidesDuby)的核型为:2n=2x=24=16m 8sm(1SAT),腺药珍珠菜(L. stenosepala Hemsl.)的核型为:2n=2x=24=10m 12sm 2st,与前人报道的有所不同。还对该属已报道的23种植物的核型进行了比较。 相似文献
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通过文献和标本考证,发现《中国植物志》第77卷第2分册和《Flora of China》第20~21卷中均误将黑穗橐吾(Ligularia melanothyrsa Hand.-Mazz.)鉴定为植夫橐吾(L. fangiana Hand.-Mazz.),而真正的植夫橐吾应处理为川鄂橐吾[L. wilsoniana (Hemsl.) Greenm.]的异名。 相似文献
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从云南省会泽县产近无毛灰岩香茶莱〔Rabdosia calcicola (Hand. -Mazz.) Hara var. subculva (Hand. -Mazz.) C. Y. Wu et H. W. Li〕叶中分得两个二萜化合物,一个为新化合物,命名为灰岩香茶菜甲素(calcieolin A),另一个为已知化合物维西香茶菜甲素(weisiensin A),经各项光谱数据和化学反应确定,灰岩香茶菜甲素为3β-羟基-1α,6α,7β,11β-四乙酰氧基-对映-贝壳杉-16-烯-15-酮(1);维西香茶菜甲素结构应为3β,6α-二羟基-1α,7β,11β-三乙酰氧基-对映—贝壳杉-16-烯-15酮(2)。 相似文献
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Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis
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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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
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
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
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
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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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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
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
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