松辽盆地深层早白垩世孢粉组合研究

系统研究了松辽盆地深层的孢粉组合,描述了４属５新种。根据孢粉化石纵向上的变化规律,自下而上划分为７个孢粉组合,并根据孢粉组合特征,比较详细地讨论了松辽盆地深层地层的时代,认为火石岭组的时代为早白垩世别里阿斯期（也有可能属于晚侏罗世提堂期）,沙河子组的时代为早白垩世凡兰吟至戈列夫期,营城组的时代为巴列姆期,登娄库组的时代为巴列姆至阿尔必早期,另外,还根据孢粉组合反映的植物群面貌,对其所属的孢粉植物区     

朝鲜安州盆地早白垩世孢粉组合

报道朝鲜安州盆地下白垩统龙盘组孢子花粉３４ 属５９ 种（包括２ 新种）,并根据孢粉组合讨论了地质时代和古气候特征。龙盘组孢粉组合以裸子植物花粉为主,蕨类植物孢子次之,出现少许原始被子植物花粉。松柏纲花粉在组合中占绝对优势;海金沙科和莎草蕨科孢子则在蕨类中占优势。根据孢粉组合,龙盘组的时代应属早白垩世巴列姆期至阿普第期;安州盆地当时气候温暖偏干,属亚热带半干旱型     

吉林九台营城组孢粉组合及古植被、古气候探讨

营城组为一套火山岩、火山碎屑岩夹含煤地层,其时代一直存有争议。本文研究了吉林省九台羊草沟煤田4个钻孔中营城组上、下段的孢粉化石,经鉴定计有60属103种,现描述16属22种,包括1个新种。根据孢粉组合的分析,认为营城组下段时代为早白垩世Berriasian期,上段为Valanginian—Hauterivian期。早白垩世该区发育以松科、罗汉松科为主,兼有麻黄科、掌鳞杉科及海金砂科、桫椤科、卷柏科、蚌壳蕨科、莎草蕨料、水龙骨科等多种蕨类植物繁茂的植物群,气候属温暖湿润的亚热带型。     

鄂尔多斯盆地西南部甘肃西峰地区延长组孢粉组合及古气候研究

鄂尔多斯盆地西南部西峰油田中上三叠统延长组长8段和长7段钻井岩心中发现丰富的孢粉化石,分别命名为Aratisporites-Punctatisporites组合和Asseretospora-Walchiites组合,组合特征分别与盆地东南部发现的铜川组孢粉组合和延长组孢粉组合相似,地质时代分别为中三叠世晚期Ladinian期与晚三叠世早期Carnian期。通过孢粉植物群类型地层分布特征及其生态环境讨论,推测盆地区中晚三叠世气候温暖潮湿,雨量充沛,植被茂盛。孢粉植物群所反映的古气候为温带—亚热带暖湿或湿热气候。这是由于本地区当时处于较低的纬度,且濒临大型湖泊,而长8—长7段沉积时期正处于湖泊扩张的鼎盛期。     

新疆塔里木盆地早白垩世孢粉组合

本文记述了新疆塔里木盆地下白垩统卡普沙良群孢子花粉55属108种包括6新种,建立了本区早白垩世孢粉组合序列,并根据孢粉组合讨论了地质时代和古气候特征,亚格列木组孢粉组合以裸子植物松柏类为主,缺乏被子植物花粉,其时代相当于贝利亚斯期至凡兰吟期;舒善河组孢粉组合仍以裸子植物为主,但出现原始被子植物花粉,时代应属豪特里维斯至巴列姆期;巴西盖组孢粉组合的海金沙科孢子和被子植物花粉都有显著增加,时代应属阿普第期至阿尔必期,本区早白垩世古气候应属亚热带干燥或半干燥型,但在巴列姆期至阿尔必期相对潮湿。     

新疆塔里木盆地早白垩世孢粉组合

本文记述了新疆塔里木盆地下白垩统卡普沙良群孢子花粉55属108种包括6新种,建立了本区早白垩世孢粉组合序列,并根据孢粉组合讨论了地质时代和古气候特征,亚格列木组孢粉组合以裸子植物松柏类为主,缺乏被子植物花粉,其时代相当于贝利亚斯期至凡兰吟期;舒善河组孢粉组合仍以裸子植物为主,但出现原始被子植物花粉,时代应属豪特里维斯至巴列姆期;巴西盖组孢粉组合的海金沙科孢子和被子植物花粉都有显著增加,时代应属阿普第期至阿尔必期,本区早白垩世古气候应属亚热带干燥或半干燥型,但在巴列姆期至阿尔必期相对潮湿。     

内蒙古开鲁盆地早白垩世阜新组孢粉组合

开鲁盆地陆家堡坳陷白垩系十分发育,富含各门类生物化石。根据坳陷内钻井所采样品,系统研究了早白垩世阜新组孢粉化石,建立以Cicatricosisporites Laevigatosporites Tricolpopollenites 为代表的孢粉组合。根据典型分子时代分布及横向组合对比,确定其地质时代为巴列姆—阿普第期,孢粉植物群反映的气候特征为潮湿的亚热带。     

新疆三塘湖盆地塘浅3井早侏罗世孢粉组合

本文对在新疆三塘湖盆地塘浅3井701－834m层段发现的孢粉植物群进行了系统的分析研究,共获孢粉45属93种（包括1新种）,疑源类化石5属5种及一个未定类型,组成以Osmundacidites-Piceites-Pinuspollenites-Quadraeculina为主的孢粉组合,根据孢粉组合特征,认为其时代应归为早株罗世晚期,对组合中主要孢粉属种可能的母体植物的生长环境进行分析,推测新疆三塘湖地区在早侏罗世晚期为温带－亚热带气候。     

鄂东南早白垩世灵乡群孢粉组合

本文根据从大冶灵乡-陈重山剖面的中部、灵乡狮子山东侧采坑和鄂城太和1孔的相当层位中所获得的孢粉组合(共67属120余种,其中新种9个,新联合2个),认为灵乡群孢粉组合属于 Classopollis、Psophosphaera-Cicatricosisporites、Schizaeoisporites-没有或极个别的出现被子植物花粉的组合类型,其地质时代应为早白垩世早期-中期(凡兰吟期-巴列姆期)。并推测鄂东南地区当时的气候属于偏干旱的热带-亚热带型。     

黑龙江西三江地区早白垩世孢粉组合

本文研究黑龙江东部西三江地区中生代煤系地层3个岩组中的孢粉组合。其中城子河组孢粉组合丰富,时代属欧特里期至巴列姆期,但目前材料尚不能对城子河组进行有意义的孢粉地层再分。穆棱组下部与城子河组的孢粉组合相似,反映植物群的渐变过程。东荣组的孢粉组合及其与邻区地层的对比关系亦有讨论,其时代有属凡兰吟期的可能。     

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.