棠垭虫(三叶虫)在陕西陇县中奥陶统的发现

棠垭虫(Tangyaia)是卢衍豪1975年建立的一个属,模式层位是湖北宜昌分乡中奥陶统的庙坡组。陕西陇县所发现的标本系一新种,定名为陇县棠垭虫(Tangyaia longxianensis sp.nov.),产于中奥陶统的平凉组。庙坡组主要为一套黑色页岩,富合笔石化石,乃滞流还原环境的沉积。平凉组也是一套以黑色页岩为主的沉积,亦富含笔石化石,这就说明生物的分布,主要受环境的控制,由于沉积环境相似,故有相似的动物群。所以笔者赞同卢衍豪等提出的“生物-环境控制论”(卢衍豪等1974;1976)。棠垭虫在陕西陇县中奥陶统的发现,进一步证实了这种观点。     

新疆塔里木盆地中-下奥陶统牙形石新种

本文研究了塔里木盆地中下奥陶统 3 个牙形石新种:Cornuodus ani sp. nov., Erraticodon tarimensis sp.nov.和Trigonodus barnesi sp. nov.,并讨论了Erraticodon Dzik一属的演化。     

新疆加波萨尔地区上奥陶统加波萨尔组日射珊瑚化石新资料

新疆东准噶尔北部加波萨尔地区上奥陶统加波萨尔组日射珊瑚化石属种繁多,数量丰富。多与大量床板珊瑚,层孔虫等一起形成礁体沉积。经室内详细鉴定,计10属32种:Taeniolites junggarensis sp. nov., Stelliporella junggarensis sp.     

贵州三都、普安早奥陶世特马豆克早期三叶虫的新材料

本文记述新发现于贵州三都、普安下奥陶统锅塘组下部的三叶虫,计8新种,分属于7属(其中1新属),即:Hospes guizhouensis (sp. nov.), H. sanduensis (sp. nov.), Pharostomina sanduensis (sp. nov.), Protarchaeganus sanduensis (sp. nov.), Pilekia transversalis (sp. nov.), Macropyge orientalis (sp. nov.), Guotangia guotangensis (gen. et sp. nov.), Leiagnostus sanduensis(sp. nov.)。在此7属中,Hospes, Pharostomina, Protarchaeganus, Pilekia四旧属在我国是首次发     

四川省直翅目-新属三新种记述

记述在四川青城山及大凉山地区采到的直翅目昆虫1新属3新种,即蚱科Tetrigidae的金沙江蚱Tetrix jinshajiangensis sp.nov.,斑腿蝗科Catantopidae的平尾蝗属Platycercacris gen.nov.,凉山平尾Plathcercacris liangshanensis sp.nov.,及突角稻蝗Oxya prominenangula sp.nov.,并附我国稻蝗属巳知种检索表。模式标本保存于陕西师范大学动物研究所标本室。     

湖南西部早志留世缨盾壳虫科(Thysanopeltidae)三叶虫二个新属

1984年8—9月,笔者与南京大学地质系古生物地层专业83级研究生吴劲薇和81级本科生李建军等六位同学,前往湖南益阳、桃源、慈利等地工作。在慈利县宜冲桥乡附近,离宜冲桥西约7华里邓家台村和何家塝村之间的志留系剖面中,找到大量的三叶虫。这些三叶虫属种单调,仅有一属一种,即:Ciliscutellumciliensis gen et.sp.nov.)。含化石地层的岩性为青灰色薄—中层状细砂岩及黄绿色页岩。化石往往保存在泥质结核内,共生的有:Glypto-graptus sp.,Monograptus sp.和蛇尾类等。在其下的层位含有大量笔石:Monograptus,Pristi-ograptus,Rastrites 及 Climacograptus 等,下伏地层为上奥陶统临湘组,两者呈假整合接触。因     

陕西陇县上奥陶统背锅山组牙形刺

背锅山组系车福鑫(1963)所建,标准剖面在陕西陇县新集川公社李家坡西北的背锅山。根据珊瑚Fauistella sp., Agetolites sp., Plasmoporella sp., Catenipora sp.及腕足类Glyptorthis sp.,车氏将背锅山组归属于上奥陶统。嗣后,中国科学院南京地     

四川古蔺下奥陶统桐梓组笔石的发现

1978年7月,笔者与龚联瓒等同志在四川古蔺大坪测制奥陶纪地层剖面时,于下奥陶统桐梓组近顶部采得反称笔石科的笔石。计有Adelograptus sichuanensis sp. nov., Adelograptus minor sp. nov., Kiaerograptus? gulinensis sp. nov., Kiaerograptus? sp.等。这些笔石与三叶虫Tungizuella szechuanensis Sheng, T. kweichowensis sheng及腕足类Tritoechia cf. quebecensis Ulrich and Cooper, Lingulella sp.等产于同一层位。因此,该地桐梓组顶部可称为Adelograptus-Tungtzuella带,并与鄂西分乡组Acanthograptus sinensis带相当。     

湖北宜昌黄花场剖面中/下奥陶统界线附近的牙形剌

重点描述宜昌黄花场剖面中 /下奥陶统界线附近的重要牙形剌共 3属、5种和 2新种Bergstroe mognathussp .nov .,BaltoniodustetrachotomusLiandWangsp .nov .,并对Oepikodusevae带和Baltoniodustriangu laris带分子的首现位置及带的含义进行厘定。作者还在此剖面大湾组下段发现北美中大陆区暖水型牙形剌Tripoduslaevis和Protoprioniodusaranda ,并确定Tripoduslaevis的首现位置在Baltoniodustriangularis带底界之上 0 .3m处。Tripoduslaevis的首次出现曾提议为中奥陶统的底界的标志 (见陈旭等 ,2 0 0 0 ) ,在宜昌黄花场剖面上Tripoduslaevis的首现位置接近Baltoniodustriangularis带底界 ,对确定中 /下奥陶统界线很重要。由于在黄花场剖面可识别出Baltonioduscrassulus—B .gladiatus—B .triangularis演化谱系 ,作者建议以B .triangularis的首次出现作为中奥陶统的底界 ,宜昌黄花场剖面为中 /下奥陶统界线的层型剖面。同时 ,文中将本区的牙形刺带与世界其它地区作了对比。     

峡东地区上奥陶统高庙坡组球节子类及其它多节类三叶虫

系统描述湖北宜昌和秭归新滩晚奥陶世庙坡组球接子类及多节类三叶虫动物群中的１４种,分属于９属、７科、。根据化石保存状态、挤压变形以及个体发育特征,对前人所报道的产于本组的有关三叶早作了大量归并、转移和重新厘定,新的材料支持解释Telephiana longicephala的性双形现象。Ａtractopyge系首次在庙坡组中发现,以往它在三峡地区只见于临湘组。文中还将新疆的一个保留命名种Ｌonchodomas cf.yohi重新命名为Ｌonchodomas zhangi sp.nov.。     

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.