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1.
报道首次在川南甘洛田坝地区晚奥陶世晚期Hirnantian期观音桥层中发现四射珊瑚Borelasma,Crassilasma和Streptelasma等属,这一珊瑚群可与黔北毕节、仁怀地区同期的四射珊瑚群对比,进一步表明扬子区晚奥陶世晚期的四射珊瑚与北欧斯堪的纳维亚同期的珊瑚群关系密切。首次报道川南甘洛田坝早志留世的四射珊瑚Brachyelasma,Crassilasma和Entelophyllum3属,这一属群可与上扬子区重庆綦江早志留世石牛栏组或滇东北大关地区早志留世Telychian期早期嘶风崖组四射珊瑚群对比。文中还报道黔北仁怀石场晚奥陶世观音桥层2个四射珊瑚新种,即Brachyelasma concavitabulatum sp.nov.和Crassilasma obliquitabulatum sp.nov.。  相似文献   

2.
黔北晚奥陶世和早志留世四射珊瑚新资料   总被引:1,自引:1,他引:0  
报道黔北早志留志中期(Middle Llandovery)地层中新发现的四射珊瑚7属--Cantrillia,Neocantrillia,Prototryplasma,Pycnostylus,Dalmanophyllum?.Rhegmaphyllum,Schlotheimophyllum,并描述产自黔东北石阡奥陶纪末期(Late Ashgill)观音桥层四射珊瑚2种--Grewingkia cf.bilateralis Neuman,Brachyelasma cf.medioseptatum(Neuman)及晚奥陶世(Early Ashgill期)涧草沟组中首次发现的四射珊瑚Crassilasma sp.。全文共描述四射珊瑚13属18种,其中6新种,它们是Crassilasma fenggangense sp.nov.,C.crebrumseptatum sp.nov.,Dinophyllum insolitum sp.nov.,Neocantrillia silurica sp.nov.,Prototryplasma guizhouense sp.nov.,Schlotheimophyllum regeneranum sp.nov.。  相似文献   

3.
扬子区中奥陶世至早、晚志留世产有丰富的四射珊瑚,尤其Ashgill期中、晚期和Llandovery世的Aero-nian—Telychian期产出珊瑚最盛。据已报道统计,该地区共有四射珊瑚124属,包括中、晚奥陶世31属,早志留世(Llandovery世)87属,晚志留世6属。其中有一些属的分类位置以及属征各家仍存在分歧。对扬子区中、晚奥陶世和志留纪四射珊瑚群已发表和笔者手中尚存资料进行系统整理之后,提出该区奥陶纪、志留纪四射珊瑚的分类意见并加以讨论,共分3个目:即扭心珊瑚目(Streptelasmatida),柱珊瑚目(Columnariida)和泡沫珊瑚目(Cystiphyllida)。其中扭心珊瑚目含有46属,分属7个科,柱珊瑚目包含37属,分属14个科,而泡沫珊瑚目包含41属,分属9个科。此外,文中提出扬子区中、晚奥陶世和早志留世四射珊瑚某些科、属的演化趋向并加以适当讨论。  相似文献   

4.
对大关地区的Telychian期嘶风崖组和大路寨组的四射珊瑚进行详细研究。嘶风崖组计有四射珊瑚18属34种,大路寨组计有四射珊瑚9属10种。描述四射珊瑚12 属19 种,其中1 新属, 5 新种,分别是:Protoketo phyllum daguanense gen. et sp. nov., Crassilasma huanggexiense sp. nov., Pseudophaulactis heae sp. nov., P.convolutus sp. nov., Shensiphyllum minor sp. nov.。论述了嘶风崖组和大路寨组四射珊瑚动物群特征及其地质意义,尤其是嘶风崖组的四射珊瑚代表了上扬子区Telychian早期的四射珊瑚动物群,完善了上扬子区志留纪兰多维列世四射珊瑚的序列和对研究该阶段四射珊瑚辐射期的进一步分析具有重要意义。  相似文献   

5.
中国志留纪鱼类微体化石的首次报道   总被引:11,自引:2,他引:9  
王念忠  董致中 《古生物学报》1989,28(2):192-206,001,T002
一、前言滇东曲靖晚志留世地层发育良好,层序清楚,无脊椎动物和脊椎动物化石以及牙形刺丰富,是研究我国志留系生物地层的一个重要地区。这套地层自下而上被命名为关底组、妙高组和玉龙寺组,是一套海陆交互相沉积,其海相地层为典型的壳相沉积,为一种近岸、浅水、富氧的沉积环境(丁文江、王日伦,1937;方润生、江能人等,1985)。本文记述的无颌类和鱼类化石就产自海相地层,它们与牙形刺和其他一些  相似文献   

6.
报道黔北毕节、仁怀和石阡地区晚奥陶世Hirnantian期观音桥层中首次发现的四射珊瑚Axiphoria,Bodophyllum,Dalmanophyllum,Leolasma,Brachyelasmaunicum(Neuman),Grewingkiaanguinea(Scheffen),结合前人报道的该层所产的Borelasma,Kenophyllum,Streptelasma,Ullernelasma等属,进一步表明黔北观音桥层四射珊瑚动物群与斯堪的纳维亚(Scandinavia)、中亚、阿尔泰地区同期珊瑚群关系密切。该动物群对阐明晚奥陶世四射珊瑚古地理关系具有重要意义。黔北观音桥层四射珊瑚十分丰富,总计有18属39种。文中共描述10属12种,其中1新属3新种,即AmplexobrachyelasmaHeetChengen.nov.,GrewingkiadensicolumnaHeetChensp.nov.,KenophyllumfossulatumHeetChensp.nov.,LeolasmaqianbeienseHeetChensp.nov.。  相似文献   

7.
新疆巴里坤三塘湖志留纪三叶虫   总被引:1,自引:0,他引:1  
新疆巴里坤三塘湖晚志留世阿苏山组三叶虫包括Ananaspis fecunda Barrande,Cheirurus barkolensis sp.nov.和Pacificurus sp.,与准噶尔盆地西北部乌图布拉格,哈萨克斯坦及捷克波西米亚的晚志留世三叶虫关系密切。另外对中国5个地区晚志留世三叶虫地层作了对比。Ananaspis,Pacificurus二属在中国是初次发现。  相似文献   

8.
扬子区中奥陶世—志留纪兰多维利世四射珊瑚产出丰富 ,尤以兰多维利世最为繁盛。目前已报道的1 2 3属 (包括中奥陶世 4属 ,晚奥陶世 2 5属 ,兰多维利世 94属 )中 ,有 30属最早出现在扬子区 ,尔后扩散到欧洲、北美和其它邻区。例如 :Calostylis最早出现在川南的中奥陶世 (Llandeilo)地层中 ;Aphyllum和Cantrillia最早出现在浙西的晚奥陶世中Ashgill地层 ;扭心珊瑚类Briantelasma ,Pycnactis和Tunguselasma等 ,最早出现在黔东北晚Ruddanian地层 ;柱珊瑚类Ceriaster、Stauria、Amplexoides、Synamplexoides等 ,泡沫珊湖类Maikottia ,Rhizophyl lum等均最早出现在黔东北的中兰多维利统 (MiddleLlandovery)。根据这些资料 ,我们认为扬子区应该是奥陶纪和志留纪四射珊瑚起源中心之一。文中论述扬子区中奥陶世—兰多维利世四射珊瑚动物群特征及其生物古地理关系。该区中奥陶世珊瑚以穿孔珊瑚类的Calostylis和Yohophyllum为特征。下扬子区浙西晚奥陶世三衢山组 (中Ashgill)四射珊瑚群有某些澳大利亚分子Hillophyllum和Bowanophyllum ;而上扬子区晚Ashgill观音桥层的四射珊瑚动物群与北欧同期珊瑚群有高度的相似性。这表明扬子区当时与欧洲具有较密切的古生物地理关系。扬子区兰多维利世四射珊瑚群与西伯利亚。  相似文献   

9.
河南晚石炭世太原组为一套海陆交互相的含煤地层,在灰岩层中含有一些保存较好的四射珊瑚化石,过去从未报道。本文记述的四射珊瑚化石是由笔者之一梁湘沅近年来在河南巩县、鹤壁及永城地区的太原组钻孔内采得的。经鉴定有4属6种1未定种,其中5新种,它们是:Lopholasma cratoseptatatum sp.nov,Lophocarinophyllum karpinskyi Fomichev,L.misticarinum sp.nov.,L.tenuiseptatum sp.nov.,L.sp.,Tachylasma carinum sp.nov.,yakovleuiella raridissepta sp.nov.。以上珊瑚中,Lopholasma最早出现在北美中泥盆统,后见于亚洲石炭系(Hill,1981),  相似文献   

10.
论十字珊瑚科(Stauriidae)的分类和演化   总被引:1,自引:1,他引:1  
前言十字珊瑚科(Stauriidae)是我国志留系最常见的珊瑚群之一,种类很多,分布广泛。除东北、内蒙古地区尚未发现外,其它各大区均有产出。主要产于华中西南区早志留世晚期,石牛栏组下段及其相当层位,中志留世秀山组(或宁强组)只有少数属种,晚志留世的尚无报道。  相似文献   

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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.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

16.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

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The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

19.
Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.
  相似文献   

20.
Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).  相似文献   

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