白既豚的骨骼和分类位置

1918年Miller比较了白既豚Lipotes vexillifer与亚河豚Inia geoffrensis的头骨与颈椎,认为白既豚是亚河豚的近亲,归属亚河豚科Iniidae。1960年,Fraser和Purves比较与鲸类听觉器官有关的骨骼及气窦(air sinus),把白既豚列入亚河豚亚科Iniinae。1972年,Brownell和Herald在关于白既豚的综述中报告其椎骨数两例,同时发表了头骨、牙齿及鼓围耳骨(tympaao-periotic)等照片。1973年,Kasuya根据鼓围耳骨的研究仍认为白既豚属于亚河豚科。1975年,陈宜瑜和陈炜报告其骨骼的某些特征,Bree和Purves报道对国外仅有三个头骨的测量。此六文中,对其骨髂的记述尚有疏误;对其分类归属都墨守Miller的观点,仅分类阶元有科或亚科之别。此外,在分类位置问题上,周开亚(1958)、寿振黄     

广西寒武纪三叶虫Dictyella完整虫体的发现及其意义

Dictyella属自1933年T．Kobayashi建立以来至今未发现完整虫体,最近在广西靖西果乐发现的tyella longispina Zhou的完整虫体标本以及其尾部的内模、外模对其分类位置的确定有重要的意义。依据其面线(为等称虫型面线)及头鞍、尾部特征,把Dictyella归于Asaphacea超科Asaphidae科和Isotelinae亚科较为合适。     

广西泥盆纪早埃姆斯期郁江组Heterophaulactis Yu,1974的再研究(英文)

Heterophaulactis Yu是作者建立并发表于1974年的一四射珊瑚属,产自广西郁江沿岸、南宁至六景一带的泥盆纪郁江组,其时代属早埃姆斯期牙形刺kitabacus带(前dehiscens带)。对此珊瑚属再行研究,是出于:1)发表在"中国南方泥盆系的新进展"一文,是与其它门类化石共同作为划分和对比地层的化石依据,只限于中文简短描述,对化石图影的展示也有严格的数量限制。尽管此属己被收录在Hill(1981)主编的古生物专论的珊瑚分册中,也只是简短的英文描述和有限的图影,未能充分展示其骨骼演变特征;2)此属的分类位置、科的归属及与相关属的属征比较与讨论,当初均未交待,应予阐明;3)Heterophaulactis属的地理分布广,遍及滇桂两省,通过再研究,其产地已扩展至中国西北地区;其地层分布又有一定的时限性,在广西仅限于郁江组下部的石州段,时代为kitaba-cus带,其它地区也仅见于下泥盆统。文中对Heterophaulactis属的模式种,Heterophaulactis semicrassa的骨骼特征及个体发育过程中的演变均作详细的英文描述和图影展示;与相关属比较之后,认为与本属关系最为密切的是产于西秦岭山区下泥盆统、发表在西北区化石图册上的有些属种,其中的有些属种可以归于本属。文中还记述一新建种Heterophaulactis yujiangense sp.nov.。文章对Heterophaulactis的分类位置和科的归属也有详细比较讨论,认为它是源出自志留纪Pycnactis—Phaulactis的演化序列,应归属于Lykophyllidae Wedekind,1927科。对Miroelasmatinae Cao,1983亚科的原始定义作全面修订后,把它归为Lykophyllidae Wedekind,1927科下的一个亚科;在对化石图册及相关文献上记述的产自西秦岭区下泥盆统四射珊瑚属种的全面修订之前,暂把以下各属置于此亚科:Heterophaulactis Yu,Miroelasma Cao,Qinlingophyllum Cao,Wenxianophyllum Cao,Protaulacophy-llum Cao,Bethanyphyllum sensu Cao,Aulacophyllum sensu Cao和Aulacophyllum sensu Zhang。     

东亚和北美当归属（广义）的果实解剖和演化

应用比较解剖研究了广义当归属在世界主要分布区－东亚和北美种类的果实结构的特征。根据分生果背腹压扁的程度、棱翅与槽的形状、果皮层次和结构、油管数目、大小和位置等稳定性状,可将果实分为５个类型,与《中国植物志》将其分为５个属,即古当归属,当归属,高山芹属,柳叶芹属和山芹属的意见相一致。古当归属为原始的类型,山芹属具有高度演化的特征。且对一些种类有分类位置提出了调整的意见和各属的演化趋势。     

中华平宽头盔虫(Platycoryphe sinensis)的个体发育及其与平背虫类系统演化的关系

本文讨论以下四个问题:一、中华平宽头盔虫的地层位置和时代.这一三叶虫与南郑小达尔曼虫(Dalmanitina(Dalmanitina)nanchengensis Lu)共生,同产的有多种笔石,有的见于晚奥陶世,有的见于早志留世,有的由晚奥陶世上延到早志留世.它的时代有过长期的争论,本文根据全部动物群的分析,认为以归入早志留世较为恰当.二、中华平宽头盔虫的分类、命名、成虫的形态特征及个体发育.三、各器官在个体发育中的变化及其意义.例如,由幼虫到成虫,关节面的扩大是和幼虫以漂浮为生转向成虫以游泳为生有密切关系的.成年期之前,背壳凸凹度大,各种沟发育,成年期之后,背壳变     

广西柳江土博出土的人牙化石及共生的哺乳动物群

在广西柳江县土博公社发现一洞穴,地层中含有人类化石和哺乳动物化石。其时代初步定为更新世晚期。人类化石仅是牙齿九枚,根据其形态特征,这些材料的系统地位似应与柳江人相当,分类上可归属晚期智人。     

龙介虫Serpula(多毛类)的摄食适应以及它与刺围脊贝Spinomarginifera的共生关系

多毛类环节动物在现代海洋分布广泛,其中能分泌钙质栖管、虫体营隐居生活的龙介虫科(Serpulidae)的许多属种,经常保存成为化石。笔者在酸蚀处理广西晚二叠世硅化标本时,获得许多Serpulidae科的不同属种,其中以Serpula数量最多,它的栖管常附着于腕足类Spinomarginifera,Leptodus,Orthotetina等属的背壳上。特别有趣的是,在合山组标准地点——来宾县合山马滩,从合山组中部的灰岩中,发现五枚     

广东大雾岭自然保护区野牡丹科植物资源调查与鉴定研究

对大雾岭自然保护区的野牡丹科植物资源进行了初步调查。依照《广东植物志》分类方法进行鉴定,调查结果为:大雾岭野牡丹科植物有野牡丹属、锦香草属和虎颜花属共三个属的5种,1个亚种。另外还发现一种植物特征与毛菍类似但叶片为7基出脉的植物,有待于进一步确定其归属。本次调查为野牡丹科植物野生资源的保护和科学利用提供了资料。     

蛇伤治疗与急救专题讲座

蛇伤治疗与急救专题讲座荀建宁广西中医学院二附院５３００１１卢惠萍广西南宁市第一人民医院５３００１２第一讲：蛇类概况第一节：蛇类的分类、分布世界上的蛇类,目前已知有２７００种,分别隶属１２个科。现有蛇类１０个科,约４００属。其中毒蛇６００余种,而对人类...     

Ningxiagraptus的再研究

甘肃平凉的平凉组和新疆柯坪大湾沟的萨尔干组中具有大量保存良好的Ningxiagraptus(宁夏笔石属)标本,为其研究提供了极佳的化石材料。本文结合新发现的材料,对Ningxiagraptus的分类位置进行厘定,对其变革历史中存在的若干问题进行讨论,为深入研究笔石的分类提供一个可供参考的案例。在对正笔石目笔石的分类和亲缘关系判别时,以笔石体的始端发育型式和特征为主,辅以笔石枝的结合方式及胞管性质是可行的方法。Ningxiagraptus虽具简单直管状胞管,第2个胞管自胎管口部向上转曲伸出,构成"U"字形始端,但其始端发育型式和始端形态却与Dicellograptus(叉笔石)近似,故将Ningxiagraptus归属有轴亚目的双头笔石超科。     

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

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.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

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     

Selection with two alleles and complete dominance

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.