论Paracarinachitids

研究证明Paracarinachitids的外骨骼都不是由8个骨板组成,骨片具有清楚的微层构造,表明它们是由叠覆的生长层组成,每个生长节上有一个小刺,在顶端下侧面前端都有肾形缺凹。同一标本上存在顶端部的融合和远顶端部的分节彼此递交的现象表明这种表象上的差异是后期次生磷灰石包裹或腐蚀的结果;其下侧缘融合和下侧面无缝隙的现象说明将Paracarinachites spinus的骨片分成头板、中间板和尾板是没有根据的。骨片表面存在的针状体是成岩作用的产物,它是粘土矿物和磷酸盐针状结晶体而不是多板纲的骨针。凡此强有力地说明Yangtzechiton是Paracarinachites的晚出同义名。根据形态功能、组织结构,特别是叠覆状排列的骨片和孤立的生长节等特征,paracarinachitids 可能与zhijinitids有密切关系,但两者是否同源尚缺少进一步的证据、据此,笔者认为将paracarinachitids 暂置于分类位置未定的具骨片后生动物较妥。     

硅藻中国新记录种——帕瓦拉桥弯藻

在对湖南省硅藻多样性研究过程中,发现其中一采自湘江的桥弯藻种类具有以下鉴定特征：(1)细胞小,长度小于29μm;(2)壳面略微呈背腹之分;(3)远缝端末梢向壳面背侧弯曲;(4)顶孔区很小,由1～3横列形态不同的两种类型孔纹组成,一种孔纹与壳面上的孔纹相似,呈狭缝隙状,另一种为圆形小孔,其内部开口上方有袋盖状硅质突出物覆盖;(5)壳面背侧中部处线纹密度每10μm为10～12条、腹侧中部处每10μm为11～13条,孔纹密度每10μm为30～40个;(6)在靠近壳面腹侧中央区具有1～2个孤点。经与帕瓦拉桥弯藻(Cymbella pavanaensis A. Vigneshwaran et al.)模式种群相比较,该文确定上述桥弯藻即为帕瓦拉桥弯藻。该文提供了对帕瓦拉桥弯藻超微结构的更多清晰认识,扩大了其地理分布区域,且是该种在中国的首次报道。     

云南永善肖滩剖面早寒武世Lapworthella (托莫特壳类)骨片化石

描述了采自云南永善肖滩剖面下寒武统石岩头组的托莫特壳类(tommotiids)骨片化石Lnpworthella rete Yue,1987,其骨片锥状或塔状,横向环脊明显,环脊尖棱状;骨片外表面具多边形网状纹饰,但无齿、瘤或纵脊等装饰;骨片可分为两种类型,即弯曲型和近直立型,前者数量明显多于后者。简要地讨论了托莫特壳类化石的分类及生物亲缘关系,认为目前为止,其仍为亲缘关系不明的化石类别。尚难断定所有的托莫特壳类骨片化石皆属于同一生物门类,因为难以证明将它们归人同类生物所依据的骨片性状是共同衍征(synapomorphy)还是由于趋同演化(convergent evolution)的结果;在缺乏躯干化石记录的情况下,离散骨片的生物亲缘关系研究较为困难。     

中国瘤(虫责)属一新种记述(襀翅目:(虫责)科)

记述采自中国陕西佛龙的瘤(虫责)属Tyloperla 1新种:双凹瘤(虫责)Tyloperla bihypodroma Du, sp. nov.,该种与尖突瘤(虫责)Tyloperla attenuata很相近,但前者第8背板近后缘形成1个隆起脊、其中部有1凹陷,后者则在背板中部形成1近圆形的隆起、其上的锥状感觉器比前者多;前者第9背板中央微凹、其前缘骨化明显、极小的锥状感觉器稀少,后者中部有1丛明显的锥状感觉器;前者翅透明,后者翅微烟褐色.新种的模式标本保存在扬州大学昆虫标本馆.     

褐稻虱的发声器官与发声机理

本文报道的是最近发现的真正的褐稻虱发声器官和发声机理。发音器位于胸、腹结合部两侧,由后足后基片和第三腹侧板向前延伸的圆瓣状骨片组成,前者顶端和后者下表面均密布片状骨质突起。当腹部振动时,圆瓣状骨片摩擦后基片顶端而发声。此结论可能在飞虱科(Delphacidac)具代表性。     

贵州关岭海龙类一新属种——双列齿凹棘龙

简要记述了产自贵州关岭小凹组的一具基本完整的骨架,在此基础上建立了海龙类的一个新属种,双列齿凹棘龙(Concavispina biseridens)。新种最明显的鉴定特征是:上颌骨前端有两列钝的牙齿,后部无齿;脊椎神经棘背缘形成V形缺口。凹棘龙与新铺龙(Xinpusaurus)独有的衍征包括上颌骨前段背向弯曲,颈椎数目小于5枚,肱骨近端比远端宽。这些特征指示凹棘龙与新铺龙可能具有较近的亲缘关系。     

硅藻中国新记录种——沃氏具脊桥弯藻

本研究利用光学和扫描电子显微镜对采自湖南省江华瑶族自治县一源头水溪流的硅藻标本进行了观察，鉴定出中国新记录一种：沃氏具脊桥弯藻(Oricymba voronkinae Glushchenko, Kulikovskiy & Kociolek)。研究结果显示该具脊桥弯藻具有以下鉴别特征：(1) 壳面呈披针形，末端钝圆；(2) 壳面平坦，壳面和壳套区别明显，被一条边缘脊分开；(3) 边缘脊两侧具凹槽；(4) 近缝端向壳面腹侧偏转，远缝端几乎呈直角向壳面背侧弯曲且在远缝末梢的背侧处有一个缺刻；(5) 壳面中央孤点外侧开口为一个简单圆形，内壳面开口为被向内生长物所遮挡的两个裂缝；(6) 壳面孔纹呈裂缝状，仅近中轴区的孔纹呈半圆至弧形；孔纹的开口被齿状突出物部分遮挡；(7) 顶孔区内侧开口被波浪形的贯壳列硅质条所覆盖但未完全封闭内侧开口；(8) 壳面中部的线纹密度为8～11条/10 μm，孔纹密度25～30个/10 μm。本文提供了沃氏具脊桥弯藻孔纹密度和原始描述中未揭示的顶孔区内壳面的详细超微结构特征。     

西藏自治区岩蜥属─新种(蜥蜴亚目:鬣蜥科)(英文)

1995～1996年,作者撰写《中国动物志·蜥蜴亚目》卷鬣蜥科岩蜥属Laudakia时,详细研究了中国科学院成都生物研究所两栖爬行动物研究室收藏的岩蜥属全部标本,发现其中采自西藏自治区波密县易贡及通麦的9号标本在《西藏两栖爬行动物》书中被鉴定为喜山鬣蜥拉萨亚种Agamahimalayanasacra,已上升为种,改隶岩蜥属,称拉萨岩蜥Laudakiasacra,实际与拉萨岩蜥不是同种动物,而是未经描述的新种,将其订名为吴氏岩蜥Laudakiawui,以纪念1973年中国科学院成都生物研究所西藏两栖爬行动物考察队已故的吴学恩队长。吴氏岩蜥与拉萨岩蜥的主要区别在于：1）前者体侧小鳞间杂以大鳞,后者则无大鳞夹杂其间;2）前者体侧各有1条明显而细的皮肤褶（本文暂名背侧肤褶）,前端始自肩前,弯曲向后,直达胯部;后者如有背侧肤褶,既不明显,亦不完整;3）前者背面斑纹呈前后缘镶暗黑边的暗褐色宽横斑,两横斑之间相距极窄,是灰褐色窄横纹;后者背面棕褐色,许多鳞片色黑,形成黑色网纹,虽偶有网纹断离者,但亦不呈明显的横斑。     

中国毡蠊属二新种和一纪录种记述(蜚蠊目,姬蠊科)

1弧毡蠊,新种 facobsonina arce sp.nov.本种与简毡蠊 facobsonina simples Hebard,1929相似,可从以下特征区分:1)腹部第7背板不特化,后者特化,具1对圆形凹陷;2)中阳茎粗壮,呈棒状具1刷状附属阳茎,后者细长无刷状附属阳茎;3)下生殖板的后端部弧状突出,后缘波状弯曲,后者后端部略弧状突出,后缘近平截.正模♂,湖北秭归九头岭,100 m,1993-06-12,李文柱采.副模:1♂,湖北秭归九头岭,150 m,1993-07-13,姚建采;3♂♂,1♀,同正模;1♂,湖北秭归九头岭,150 m,1993-06-13,黄润质采;1♂,湖北秭归九头岭,150 m,1993-06-12,姚建采;1♂,广西龙胜花绑林区,1963-06-7,刘思孔采.2扭毡蠊,新种,Jacobsonina tortuosa sp.nov.本种与特毡蠊 Jacobsonina aliena(Brunner,1893)相似,但可从以下特征区分:1)下生殖板左侧角呈倒"L"形缺刻,右侧角圆滑呈指状,左侧缘波状弯曲,右侧缘明显弧状突出,但后者的侧缘微凹入,端部窄且平截;2)中阳茎粗壮,呈棒状无附属阳茎,后者中阳茎弯曲且其下具1粗壮的骨片.正模♂,云南西双版纳景洪,650 m,1958-07-5,孟绪武采.副模:2♂♂,云南西双版纳大勐龙,650 m,1957-06-17,王书永采;1♂,同正模;1♂,云南西双版纳大勐龙,650 m,1957-07-10,洪淳培采.     

绿盲蝽腹神经节的解剖结构

【目的】揭示绿盲蝽Apolygus lucorum腹神经节的组成结构。【方法】采用免疫组织化学染色方法,利用突触蛋白抗体对绿盲蝽成虫的腹神经节进行免疫标记,激光共聚焦扫描显微镜扫描照相获得原始数据,用图像分析软件进行标记,构建三维结构模型。【结果】绿盲蝽成虫腹神经节位于腹神经索的末端,与其前方的后胸神经节和中胸神经节紧密融合,形成后部神经节。与脑和胸神经节类似,腹神经节由周围的细胞体和内部的神经髓构成。腹神经节的神经纤维束主要包括位于腹侧的两条纵向神经连索和向两侧发出的9束神经纤维。9束神经纤维连接着9个神经原节,即富含突触联系的神经髓。这些神经原节紧密融合,无明显的边界,最后两节形成膨大的末端腹神经节。两侧的神经原节由横向的神经连锁连接起来。腹神经节外周的细胞体数量较多,排列紧密,大小一致,仅在前端背侧中间和后端腹侧中间位置分别有2个和5个体积较大的细胞体。【结论】本研究结果明确了绿盲蝽腹神经节的结构,为进一步研究昆虫的行为调控及神经系统发育和演化奠定一定的形态学基础。     

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.