广东封开发现的人类牙齿化石

在广东封开峒中岩发现的一枚人类右上第二前臼齿化石,其形态与现代人特征基本一致;同时发现的哺乳动物化石有华南巨貘、中国犀等九种;时代为晚更新世。     

云南昭通水塘坝中新世末期古猿化石点的云南貘化石(英文)

此前,中国晚中新世到早上新世的貘化石发现较为稀少。最近几年,在云南省昭通市水塘坝禄丰古猿化石点发现了数量可观的中新世晚期貘化石,其时代为6~6.5 Ma。新发现材料包括左上颌骨带P2-M2、4件下颌骨带基本完整颊齿列、若干零散牙齿。新材料可归人先前报道的小型貘类——云南貘Tapirus yunnanensis。云南貘比甘肃的和政貘Tapirus hezhengensis时代较晚,体形也稍大;两者都比上新世一更新世的貘类明显较小。新发现的化石材料对更全面认识云南貘的特征提供了新信息。在中一晚中新世期间,云南是我国貘类动物的演化中心,先后发现的化石点有开远(小龙潭)、禄丰(石灰坝)、元谋(小河、竹棚、雷老)、昭通(水塘坝)及其他地点。在晚新生代期间,我国貘类动物演化的主要变化趋势是体形逐渐增大,这一特点或许具有时代意义。在中国发现的中新世貘类毫无例外都是体形较小的类型,这与欧洲及北美的情况迥异。     

江西萍乡上栗县晚更新世哺乳动物化石发现

2014~2015年在江西萍乡上栗县长平乡发现的杨家湾哺乳动物化石点,是江西省为数不多的更新世化石点中出土化石最为丰富多样的:目前已在杨家湾1号洞发现数千件哺乳动物牙齿化石,初步鉴定出40个属种;在化石数量上,野猪占绝对优势,其它常见种类还有鹿类、豪猪、黑熊、小型食肉类、鬣羚、水牛、犀牛及猴类等,而长鼻类及貘相对较少;在本地区同时代化石点中,猴类化石最丰富,食肉类属种也更多样。灭绝种类有巴氏大熊猫、最后斑鬣狗、德氏狸、剑齿象及巨貘等。从动物群组合来看,杨家湾1号洞与湖南道县福岩洞古人类化石点最为相似,其时代也应当属于晚更新世。     

鄂西“南方古猿”和印尼早更新世若干人类化石

在鄂西发现的四枚臼齿化石曾被认为是南方古猿的。鄂西臼齿,从其齿冠尺寸和形状等来看,与非洲的有关材料对比,更接近人属成员的;与印尼早更新世有关的化石对比,与魁人等的很相似。直立人牙齿的演化趋势和变异性表明:鄂西臼齿以及印尼早更新世人类下颌骨化石更大的可能是代表一类时代较早的直立人。     

陕西洛南人牙化石及其地质时代

在陕西省洛南县洛河左岸洞穴中,发现一古人类上臼齿,其特点与郧县人牙化石很相似。与人牙化石共存的有大熊猫和獏。后二者比华南洞穴中常见的同类化石明显小,比广西柳城巨猿洞中的小型者要大。从化石特点分析,洛南人牙化石及其所在沉积层的时代为中更新世早期(也有早更新世晚期的可能)。     

新研究显示云南昭通古猿分布区曾是貘类动物演化中心

貘类动物起源于北美始新世早期,体型较小,后来发展为美洲和欧亚大陆特有动物.我国晚中新世到早上新世的貘化石发现很稀少.1978年,北京自然博物馆时墨庄等人在云南一四三煤田地质队的协助下在昭通永乐褐煤矿采掘到一批哺乳动物化石,他们依据其中的几件貘化石下颌骨残段建立一新种——云南貘,并认为其地质时代为距今250万年至300多万年的晚上新世.但当时这一发现没有得到足够重视,导致野外和室内研究工作中断多年.     

湖北建始县又发现巨猿牙齿化石

1970年,中国科学院古脊椎动物与古人类研究所在我省建始县高坪龙骨洞中发现了5枚巨猿牙齿化石和大量的哺乳动物化石。经研究,巨猿牙齿化石的时代为早更新世晚期。     

河北蔚县大南沟哺乳动物化石及其地层时代

近年来,在河北蔚县一带晚新生界陆相沉积中,陆续发现有四个不同的化石层位,使这一地区晚新生代地层关系更加明确。本文所记述的大南沟化石点中的哺乳动物化石属于泥河湾期哺乳动物群,其地层时代为早更新世。     

贵州毕节何官屯新发现巨猿及早更新世哺乳动物化石

2007年8月,中国科学院古脊椎动物与古人类研究所、贵州省博物馆、贵州省考古所及毕节地、市文管部门联合组成野外考察队,对毕节何官屯扒耳岩及周边地区进行考查.根据当地化石爱好者孙贵川等人提供的材料和线索,在扒耳岩采石场发现巨猿及早更新世哺乳动物化石.     

中国古动物馆珍品馆藏——锯齿

化石名称：锯齿似剑齿虎 Homotherium crenatidens 化石描述：近乎完整的头骨（侧面暴露其发育的显著裂齿）和下颌骨 生活时代：早更新世（距今约200万年前） 化石产地：安徽省繁昌县     

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.