新疆南部早石炭世层孔虫新资料及其古地理意义

本文描述的层孔虫产自新疆南部西昆仑山北缘阿克陶地区下石炭统库山河组。经研究鉴定,计有Platiferostroma longtangshanense Wang,P.microcystosum sp.nov.,P. multibrachiatum sp.nov.,P.xinjiangense sp.nov.等。共生化石有腕足类、双壳类及四射珊瑚、床板珊瑚。这些层孔虫在新疆境内早石炭世早期地层中尚属首次发现,它增补了该区下石炭统的化石依据,对于国内外同期含层孔虫化石的地层划分和对比具有重要的意义。     

鄂西中生代含煤地层中的孢粉组合

鄂西中生代含煤地层素称“香溪群”,典型剖面在秭归县香溪镇。这一煤系早年曾被划分为上三叠统和下侏罗统两部分(谢家荣、赵亚曾,1925)。后来,斯行健(1949)研究了其中的植物化石,认为其时代为早侏罗世,“香溪煤系”始以“香溪植物群”而闻名中外。近年由于工作的深入,不少地质工作者又提出了“香溪群”下部属上三叠统的可能性,但化石却一直没有系统地采集和研究。     

湘西南、桂东北早侏罗世孢粉组合

1976年,我所对湘西南、桂东北中生代含煤地层与古生物群进行系统的调查。采集了大量的动植物化石和孢粉样品。在湖南零陵冯家冲、江永桃川、兰山园竹及广西贺县西湾等地的下侏罗统样品中,发现丰富的孢粉化石。对这些孢粉化石的研究,关于认识华南早侏罗世孢粉组合,以及确定华南早侏罗世地层之存在,具重要意义。赵鼎担任孢粉样品分析,毛继良摄制图影,徐宝瑞清绘插图,均致谢忱。     

广东南雄盆地古新世早期孢粉组合

引言根据中国科学院和西德Max-Plank协会的合作课题“上白垩统,特别是白垩系-第三系交界的全球事件”的陆相部分项目,由中国科学院古脊椎动物与古人类研究所、南京地质古生物研究所和西德波恩大学古生物研究所组成的综合考察队,分别于1983和1984年9—10月,在广东南雄盆地进行野外工作。我们在南雄盆地的杨梅坑-大塘、堂田-飒门垭、百花潭-武台岗以及南雄县附近的古子坑剖面,采集了近500层孢粉样品。在大塘剖面的南雄组、上湖和罗佛寨组中获得了孢粉化石。其中南雄组中的化石孢粉极少,达不到化石孢粉组合的统计     

宁夏六盘山盆地晚三叠世孢粉组合及其地层意义

对宁夏六盘山盆地炭山、窑山及上流水等３条剖面中原划为中侏罗统延安组下部含煤地层的２１块岩样进行了孢粉分析,获得丰富的孢粉化石,鉴定出７６属１４４种,建立了Ｄｉｃｔｙｏｐｈｙｌｌｉｄｉｔｅｓ－Ａｒａｔｒｉｓｐｏｒｉｔｅｓ－Ｃｙｃａｄｏｐｉｔｅｓ组合。通过与国内外相关孢粉组合对比,认为该组合地质时代应属晚三叠世。首次以孢粉化石为依据,确认了六盘山盆地上三叠统延长组的存在。     

新疆塔北隆起原油孢粉集合与油源岩

鉴定了从新疆塔里木盆地塔北隆起含油区原油中萃取出的孢子花粉化石66属135种,基于原油孢粉集合组成特征的研究,确定了该含油区油源岩的时代和层位,并讨论了油气运移的通道、方向、路线。期次等问题。研究结果确认,中三叠统克拉玛依组,上三叠统黄山街组和塔里奇克组;下侏罗统阿合组和阳霞组;中侏罗统克孜勒努尔组和恰克马克组是塔北含油区的重要油源岩系。     

江苏句容上二叠统龙潭组孢粉组合及孢粉热变指数和有机质类型

通过对苏南句容A10井的孢粉研究,首次发现了上二叠统龙潭组孢粉化石。根据孢粉组合特征。与国内同时期的孢粉组合进行了比较和讨论,并用孢粉热变指数和有机质类型,对龙潭组进行了油气评价。为苏南地区晚二叠世的地层对比,提供了新的古生物依据。     

新疆昆仑山西部中石炭世(竹蜓)类化石

1957年5月至10月间,为配合地质部的一个地质队做地层古生物工作,笔者曾随本所张日东、俞昌民和陆麟黄三同志,赴天山南部及昆仑山西部地区,测制了若干古生代地层剖面。关于中石炭统部分,以在莎车县卡兰乌依及濮德若二地出露较好,含(竹蜓)类化石比     

德国Palatinat北部爱森贝格盆地早第三纪孢粉组合时代的确定

艾森贝格盆地（Eisenberg Basin)位于梅因茨盆地（Mainz Basin)西南部,为莱茵地堑的一部分,因为化石稀少,这里的地层和梅因茨盆地典型的第三纪地层很难对比,因此,它们的地质时代长期处于争论中。对于Lautersheim 1钻孔及Lautersheim附近地层露头的孢粉地层学研究表明,这一地区的第三纪可以三分,Lautersheim 1钻孔的下部属于中始新统,相当于Krutzsch的SPP 15／16带,该钻吉中部的一部分可置入早渐新世,相当于SPP19带;这部分可以再分为上下两部分;下部含大量始新世微体植物化石,而上部此类化石很少,上部属于下渐新统,与含孢粉的Sandpit “Friedlich”可以对比。Lautersheim 1钻孔最上部属于晚渐新世（早Chattian),与“过滤层”顶部及“淡水层”底部可以对比,其所含的孢粉和Marxheim组合可以比较,相当于SPP 20F／G带。     

辽西义县组孢粉植物群指示的古气候条件

迄今为止,在辽西北票义县地区的下白垩统义县组二段沉积层中,已发现孢粉化石62属,82种,藻类化石3种。本文对产于不同地点沉积层中的孢粉化石进行了系统研究和总结。根据孢粉母体植物形态和生态特征、生长的气候环境和干湿度环境,对义县组二段的孢粉植物群进行了植被类型、气候带类型和干湿度类型的统计和划分,认为义县组二段沉积时期,其孢粉植被类型为针叶林,所处的气候环境为湿润的亚热带一暖温带。由于植被成分中存在落叶阔叶植物和旱生植物,推测气候环境存在季节性变化,间有干旱一半干旱气候条件。     

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.