蜂巢珊瑚类横板珊瑚的体壁构成及有关问题

一、前言本文所指蜂巢珊瑚类,包括所有具联接构造的块状复体横板珊瑚,即蜂巢珊瑚亚目(含蜂巢珊瑚超科、厚孔珊瑚超科)和槽珊瑚亚目(含槽珊瑚超科、小槽珊瑚超科)。多年来,在研究珊瑚体显微构造时,最先为人们注意的是体壁的构成。本文以“构成”一词代表构成体壁的部分,而以“微细构造”一词代表每一部分的构造细节。微细构造又分显微构造和超微构造两类,分别代表光学显微镜下和电子显微镜下所见的微细构造。由于光学显微镜放大倍数超过40倍后,视野昏暗,形象模糊,难以分辨。而横板珊瑚的基     

论实轴型中柱皱纹珊瑚的分类

具实轴型中柱的皱纹珊瑚的分类位置至今尚未取得统一。这类珊瑚的轴部由纤状组织构成,它不同于复中柱或皱形复中柱,它的形成与主隔壁,对隔壁或一级隔壁内端没有关系,是皱纹珊瑚中一类独立发育的轴部构造。具实轴型中柱的珊瑚可以独立建立新目,称Ｃｙａｔｈａｘｏｎｉｉｄａ ｏｒｄ．ｎｏｖ．。按照组成实轴的纤状组织类型和实轴形态,可以划分为３科,即Ｃｙａｔｈａｘ－ｏｎｉｉｄａｅ ｅｄｗａｒｄｓ ｅｔ Ｈａｉｍｅ,１     

论文采尔珊瑚(Wentzelella)

文采尔珊瑚(Wentzelella)是我国南方、日本、苏联、新西兰、印度、伊朗、伊拉克、意大利、德国和阿尔卑斯山区等地早二迭世地层内常见的一类珊瑚化石。1927年,Grabau创建了这个属,并指定Lonsdaleia salinaria Waagen et Wentzel 为属型。他给予的定义是:“复体,柱状个体,隔壁始端直抵外壁,边缘未发育成像Lonsdaleia 属的泡沫带,复中柱呈朗士德珊瑚型”。Wentzelella 正式公诸于世,则见于黄汲清的论文中。自Grabau 建立这一个属以来,古生物学家列入Wentzelella 属的种和变种,据笔者所知,计有32个;但     

论志留纪陕西珊瑚属Shensiphyllum Ge et Yü,1974

ShensiphyllumGeetYü,1974为丛状复体珊瑚,以发育一列马蹄型鳞板,羽榍扇形排列为主要特征,是志留纪四射珊瑚已知唯一发育马蹄型鳞板的属。该属在我国上扬子区广泛分布于上兰多维列统(Llandovery)特列奇阶(Telychian)中,主要产自川北、陕南的宁强组、云南大关的大路寨组(中、上Telychian阶))、湖北长阳的纱帽组及四川朝天的王家湾组(下特列奇阶)。文中报道和描述川北朝天王家湾组中发现的3个新种Shensiphyllumsimplexsp.nov.,S.proliferumsp.nov.,S.intermediumsp.nov.。王家湾组是已知ShensiphyllumGeetY櫣产出的最低层位。详细讨论该属的骨骼构造特征、生长繁殖方式,探讨该属起源及其演化,根据新资料修订该属的属征,赞同将该属置PhacellophyllidaeWedekind科。     

异珊瑚研究的新进展

通过对异珊瑚形态构造特征分析,进一步阐明了隔壁的发生方式、隔壁发育阶段、隔壁生长的变演性、隔壁基端与外壁的关系、隔壁的微细构造及其所含的化学成份,枝体表壁和壁面上的构造物特征,横板的形态及枝体繁殖的方式.通过异珊瑚生长特征的分析,探讨了它们的生活环境.结合地层资料归纳了异珊瑚的时空分布并将异珊瑚重新归纳为6科2亚科16属.     

中国Waagenophyllum (Waagenophyllum)种的分支分析

在对材料产自我国的Waagenophyllum (Waagenophyllum)的种进行系统分类厘定的基础上,以Waagenophyllum (Liangshanophyllum)wengchengense作为外类群,对22个种的10个性状进行分支分析,探讨各种之间的系统发育关系。分支分析结果表明,Waagenophyllum (Liangshanophyllum)与Waagenophyllum(Waagenophyllum)关系很近,一些研究者提出的Liangshanophyllum作为一个独立属的分类意见值得商榷。     

Maikottia属骨骼微细构造及其分类

Ｍａｉｋｏｔｔｉａ Ｌａｕｒｕｓｅｖｉｃｈ,１９６７属是泡沫珊瑚目中较特殊的类型,呈多角块状复体。经电镜研究表明,其骨骼微细构造以晶片型层状骨骼为主,隔壁刺由复式杆晶榍组成,层状骨骼包绕隔壁刺,在隔壁刺内包绕和联结单杆晶榍。体壁和横板均由层状骨骼组成。本属的纤状骨骼属较原始简单类型－晶粒和短轴晶柱,它组成复式杆晶榍内单杆晶榍的轴带,并呈分散状排列。根据该属为泡沫珊瑚类型隔壁及复式杆晶榍,将其归入泡     

新疆早二叠世阿克苏柯坪珊瑚的种内变异

通过对产自新疆柯坪地区的阿克苏柯坪珊瑚(Kepingophyllum aksuense)的大量薄片观察,发现该类珊瑚在珊瑚体单骸形态、横板带宽度与泡沫板带宽度之比、隔壁长度、横板的形态、隔壁数目、隔壁数目与珊瑚骸直径之比等六个方面存在很大变异。此外,该类珊瑚中存在明显的周期性生长变异现象,表现在泡沫板的排列疏密相间。与模式标本的对比研究发现,此类珊瑚的群体间变异相对较小。     

聚类分析法对镣珊瑚类的修订

镣珊瑚类是奥陶纪-志留纪地层中常见的以链状珊瑚复体为特征的一类床板珊瑚,地理分布广泛,研究历史较长。但不同学者对其骨骼构造特征的分类学意义认识不一,使得类群中许多属的定义和范围长期存有争议。本文结合我国的已发表材料,对镣珊瑚的分类进行简要讨论,依据隔壁刺的有无将镣珊瑚分为Catenipora和Quepora两属,认为Procatenipora和Eocatenipora分别是前者和后者的同义名。运用聚类分析的方法对我国镣珊瑚类的种进行修订。     

聚类分析法对镣珊瑚类的修订北大核心

镣珊瑚类是奥陶纪-志留纪地层中常见的以链状珊瑚复体为特征的一类床板珊瑚,地理分布广泛,研究历史较长。但不同学者对其骨骼构造特征的分类学意义认识不一,使得类群中许多属的定义和范围长期存有争议。本文结合我国的已发表材料,对镣珊瑚的分类进行简要讨论,依据隔壁刺的有无将镣珊瑚分为Catenipora和Quepora两属,认为Procatenipora和Eocatenipora分别是前者和后者的同义名。运用聚类分析的方法对我国镣珊瑚类的种进行修订。     

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.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

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     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

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.     

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.