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多花黄精和安徽黄精叶片发育的比较解剖学研究 总被引:1,自引:1,他引:0
对多花黄精(Polygonatum cyrtonema)和安徽黄精(P.anhuiense)不同发育时期的叶片进行了比较解剖学研究。结果表明:(1)在叶片发育过程中,气孔器指数都是由低到高,达到最高值后再逐渐降低并趋于稳定;(2)叶片长宽比在发育过程中都呈上升趋势,且与叶片形状之间有一定的相关性,叶片长宽比与表皮细胞长宽比之间没有明显的相关性;(3)两者叶片的上下表皮细胞的发育方式基本一致,都是由表皮细胞进行横向和径向生长的过程;(4)在叶片的分化过程中,首先分化出来的是表皮,其次是叶肉,最后是叶脉;(5)多花黄精的叶缘在发育早期叶肉中有大型薄壁细胞出现,但叶片成熟时,大型薄壁细胞消失或继续保存,而安徽黄精在整个发育过程中,叶肉中都未见大型薄壁细胞出现。该研究为黄精属互生叶类和轮生叶类植物的叶片发育研究积累了实验资料。 相似文献
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《中国野生植物资源》2015,(4)
黄精是我国传统的中草药,属于药食同源性药材。黄精多糖作为黄精的一种重要药用成分,具有多种生理功效。本文就近期我国学者对黄精多糖的化学组成、含量测定方法、提取方法、主要功能特性等方面的研究进行了分析总结,对黄精多糖的的研究前景进行了展望,以期为黄精多糖的开发利用提供参考。 相似文献
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黄精引种驯化栽培研究 总被引:3,自引:0,他引:3
邓颖连 《中国野生植物资源》2011,30(2):57-59
随着天然药物、植物药的开发利用程度的加大,给药用植物资源保护及可持续利用带来了巨大压力和契机。本试验于2004年夏季开始,先后从内蒙古乌兰察布市蛮汉山引种了黄精野生药用植物,对其种子特性、繁殖方法、移栽时期、栽培技术、生长发育特性及适应性进行了引种驯化栽培研究,通过3~4年对黄精进行引种驯化栽培研究,引种成功。形成了一套较为完整并切实可行的人工栽培技术,为大面积商品化人工栽培推广应用奠定了基础。 相似文献
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为明确发生在贵州省施秉县的黄精叶斑类病害的病原菌,通过形态学和分子生物学方法对病原菌进行了鉴定,并对其生物学特性进行了初步研究。形态特征及rDNA-ITS、β-tubulin和tef1多基因序列分析表明,该病原菌为棕榈拟盘多毛孢Pestalotiopsis trachicarpicola。生物学特性研究结果表明,该菌菌丝体适宜生长温度为15-30℃,最适温度为28℃;最适pH值为5;以葡萄糖为碳源、酵母浸膏为氮源比较适合菌丝体的生长;菌丝体生长的最佳培养基为PDA;光照对菌丝体生长无明显影响;菌丝体致死温度为45℃。 相似文献
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瓦屋山异黄精(Heeropolygonatumxulw.K.BacetM.N.Tamura)属百合科异黄精属,发表在日本刊物ActaPhytotax.Geobot.49(2):143-146(199)。它的拉丁名以四川大学许介眉教授的姓氏命名,因为他在四川百合科植物种类研究中作出了很大贡献。其模式标本1998年5月19日采自 相似文献
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中药黄精为百合科黄精属植物黄精(Polygonatum sibiricum Delar.ex Redoute)、滇黄精(Polygonatum kingianum Coll.et Hemsl)与多花黄精(Polygonatum cyrtonema Hua)的干燥根茎,具有悠久的药用历史。黄精多糖是黄精中最重要的活性化合物之一,具有抗氧化、调节免疫、抗肿瘤、抗骨质疏松、降血糖、降血脂和抗动脉粥样硬化等多种生物活性,已经成为黄精开发应用研究的热点。本文综述了近年来国内外对黄精多糖的结构特征、生物活性及其相关机制的研究进展,以期为黄精多糖的深入研究与开发提供理论参考。 相似文献
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药用植物黄精种子休眠特性研究 总被引:5,自引:0,他引:5
从黄精(Polygonatum sibiricum Red.)种子的形态、解剖结构、果实及种子部分抑制物质的生物测定和种子成熟过程中内源激素ABA含量的变化等方面研究种子的休眠特性。结果表明:黄精种子休眠属于综合休眠,首先黄精种子秋季采收后其种胚存在生理后熟,是导致黄精种子深休眠的主要原因;其次黄精种子的胚乳细胞小、细胞质浓厚、排列致密,胞间隙小,影响物质的共质体运输;果实及种子中含有不同程度的发芽抑制物质;种子成熟时ABA含量升高是导致种子休眠的又一原因。 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