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报道了越南蜘蛛1新纪录科,开普蛛科Caponiidae。描述了越南1新纪录种:刚毛老挝蛛Laoponia saetosa Platnick & Jager,2008和1新种:拟刚毛老挝蛛L.pseudosaetosa sp.nov.。这2个种的雄性触肢器的形状基本相同,但是触肢器生殖球的大小差异十分显著,该结构在拟刚毛老挝蛛中显著小于刚毛老挝蛛(P<0.05)。标本采集于越南北部的3个国家公园:库风国家公园(Cuc Phuong National Park),吉婆岛国家公园(CatBa National Park)和三岛国家自然公园(Tam DaoNational Park)。拟刚毛老挝蛛,新种Laoponia pseudosaetosa sp.nov.(图6~8,10,13)正模♂,副模20♂♂,越南永丰省三岛国家公园,2007-04-01至2008-03-31,范鼎飒采。词源:新种因生殖器结构与刚毛老挝蛛Laoponiasaetosa Platnick & Jager,2008相似而得此名。 相似文献
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昆虫卓越的爬行和附着能力来源于其精细的功能性黏附系统。根据形态结构的不同,昆虫的黏附系统可分为光滑型黏附垫和刚毛型黏附垫两种类型,二者在分泌液的支持下均能附着于几乎所有的光滑或粗糙的物体表面,而且这两种类型的黏附垫与界面的附着的形成均主要依赖于范德华力。本文综述了昆虫足的附着机制,包括光滑型和刚毛型两种黏附垫的结构和其形成附着的机理,以及黏附垫分泌液的功能、组成成分和释放机制,阐明了昆虫如何巧妙地解决稳定附着和快速脱附这一矛盾的问题,讨论了诸如界面的理化性质和环境湿度等环境因素对昆虫附着的影响,以期帮助人们深入地理解昆虫足的附着机制,并为其在仿生学等方面的应用提供理论依据。 相似文献
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通过对现生环节动物门(Annelida)多毛纲(Polychaeta)叶须虫目(Phyllodocidae)鳞沙蚕亚目动物(Aphroditiformia)软背鳞虫(Lepidonotus helotypus Grube,1877)的鳞片、刚毛等疣足附属物的超微结构观察及其与Wiwaxia骨片的比较研究,探讨Wiwaxia的系统分类位置。研究结果表明,软背鳞虫的刚毛与Wiwaxia骨片具有以下相似性:1)两者表面均具有浅纵纹;2)均向身体背中线方向倾斜或弯曲;3)着生方式均以刚毛囊或类似根状基的结构插入软组织。此外,文中首次对鳞片上的锥形突起与Wiwaxia骨片的相似性进行比较和探讨。结果显示,Wiwaxia骨片与鳞沙蚕刚毛具有一定相似性,但在形态上仍存在显著差异(如二者的排列方式不同,Wiwaxia骨片上不存在鳞沙蚕刚毛的覆瓦状结构等)。 相似文献
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弦音器是昆虫类特有的一种机械感受器,亦称弦音感受器或剑梢感受器。它主要具有感知外界声压和体内肌肉运动的听觉功能,研究弦音器的机能结构对揭秘昆虫听觉的神经机制有重要的科学意义。本文从弦音器多样性和进化入手,重点综述了弦音器的微细结构、基因功能定位、声音感受分子机制及其声压增幅分子生物物理学原理,为昆虫听觉仿生学的研究提供了理论依据。 相似文献
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为初步探讨园蛛总科内网型不同的蜘蛛间分子系统发生关系,测定了9种蜘蛛核18S rRNA基因的部分序列。联合GenBank中的2种蜘蛛18S rRNA基因序列数据,用NJ法、MP法和ML法重建分子系统树,结果表明:(1)织圆网的园蛛科和肖蛸科蜘蛛在园蛛总科中不是姊妹群;(2)不织圆网的球蛛科和皿蛛科也不是单系发生,证实了皿蛛片网和球蛛网独立起源的观点;(3)皿蛛科蜘蛛的分子系统发生地位与肖蛸科较近、而与园蛛科较远,这表明皿蛛科和园蛛科问雄性触肢结构的相似性很可能是类似而不是同源相似。 相似文献
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斜纺猫蛛对茶尺蠖幼虫捕食作用的初步研究 总被引:2,自引:0,他引:2
在室温条件下测定了斜纺猫蛛亚成蛛及成蛛对茶尺蠖1~2龄幼虫的日捕食量及功能反应,捕食者自身密度效应和温度对功能反应的影响,斜纹猫蛛亚成蛛及成蛛对茶尺蠖幼虫的功能反应均呈HollingⅡ型反应,模拟模型分别为Na=0.9195Nt/(1+0.004703Nt)和Na=0.92268Nt/(1+0.005081Nt)自身密度反应模型分别为E=0.5419P^-0.6052和E=0.5139P^-0.5 相似文献
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本文报道了采自湖北省利川县的暗蛛科(Amaurobiidae)隙蛛属(Coelotes)一新种和漏斗蛛科(Agelenidae)漏斗蛛属(Agelena)一种蜘蛛:利川隙蛛,新种C.lichuanensissp.nov.和灰色漏斗蛛A.poliosataWang,1991。 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