云南复叶耳蕨属植物孢子形态研究

利用扫描电子显微镜对30种复叶耳蕨孢子形态进行了观察,结果显示:(1)复叶耳蕨孢子两侧对称,单裂缝,裂缝长度为赤道轴的1/2～3/4,极面观为卵圆形或椭圆形,赤道面观为半圆形或近圆形,大小为(25.45～43.43)μm×(18.09～31.92)μm。(2)复叶耳蕨孢子主要纹饰有:片状、刺状、瘤块状、翅状、脊状、耳状及粗糙7种类型。(3)根据孢子形态特征,对长期存在分类争议的种进行了探讨,并列出基于孢子形态的检索表。结果支持:将灰脉复叶耳蕨处理为西南复叶耳蕨的异名;大姚复叶耳蕨处理为日本复叶耳蕨的异名;镰形复叶耳蕨作为南川复叶耳蕨的异名;钝羽复叶耳蕨和浅裂复叶耳蕨孢子纹饰一致,因此其亲缘关系较近。     

鳞毛蕨科的孢子形态研究

对鳞毛蕨科及其相近类群的19属65种的孢子形态进行了光学显微镜观察,并对其中12属30种进行了扫描电镜观察。鳞毛蕨科的孢子左右对称,极面观为椭圆形、近球形,赤道观为肾形,极轴/赤道轴的比值为0.60～0.86;单缝孢,裂缝长度约为孢子全长的1/2～3/4,属中至大型孢子。鳞毛蕨科具有多样性的外壁纹饰:不仅包括刺状、瘤状、颗粒状、脊状、窗孔状、耳状、片状及翅状等几种基本类型,而且还存在一些中间过渡类型。根据孢子形态特征,对本科的属间关系进行了探讨。孢子形态特征的相似性支持假复叶耳蕨属、肉刺蕨属、球盖蕨科与鳞毛蕨属的近缘关系,黔蕨属与复叶耳蕨属间的近缘关系。玉龙蕨属的两个种的孢子纹饰与耳蕨属的部分种一致,支持将玉龙蕨属作为耳蕨属的异名处理。拟贯众属独特的翅状纹饰支持将其从鳞毛蕨科中分离出去。     

中国蕨类植物孢子形态的研究ⅩⅢ.叉蕨科

利用扫描电镜对中国产叉蕨科7属34种植物孢子的形态进行了观察。叉蕨科植物孢子为左右对称,极面观为椭圆形,赤道面观为半圆形、超半圆形或豆形;极轴长为18～38μm,赤道轴长为23～57μm;单裂缝,裂缝长度为孢子全长的1/2～2/3;孢子具脊状、翅状、刺状和耳状4种纹饰,孢子表面有时具细刺、颗粒或孔。通过孢粉学分析,叉蕨科依据孢子形态特征和依据孢子体形态特征的分类结果并不一致,孢粉纹饰类型呈现一定程度的属间交叉;支持将叉蕨科和鳞毛蕨科进行重新划分的MAARTEN J.M的新分类系统。     

秦岭耳蕨属孢子形态研究

本文在经典分类基础上,就秦岭地区常见的7种耳蕨属(Polystichum)植物,采用光学显微镜和扫描电子显微镜,对其孢子形态进行了系统的观察。在扫描电镜下,从形态和周壁纹饰上可将孢子分为两种类型:一种是周壁具明显的褶皱,其表面分布稀疏或较密集的小瘤状或小疣状突起,无穿孔;另一种周壁较薄,褶皱具明显穿孔,穿孔大小及形状不一致,周壁表面有颗粒状或小刺状突起。研究表明,孢子形态、周壁纹饰在种间具有明显差异,从而可为本属种间分类提供孢粉学依据。     

广西蕨类植物孢子形态的研究Ⅱ.铁角蕨属

利用光学显微镜和扫描电子显微镜对广西产9种铁角蕨属植物即拟狭翅铁角蕨、黑柄铁角蕨、剑叶铁角蕨、长生铁角蕨、岭南铁角蕨、石生铁角蕨、阴湿铁角蕨、半边铁角蕨和细裂铁角蕨植物的孢子形态进行了观察,对每个种的形态特征进行了详细描述,其中5种铁角蕨属植物孢子的表面纹饰为首次报道。结果如下:9种铁角蕨属植物孢子都为单裂缝,两侧对称,极面观为椭圆形或近圆形,赤道面观为肾形、椭圆形或近圆形。主要纹饰类型有翅脊状纹饰、翅状纹饰和脊状纹饰类型。讨论了各种间的差异。为铁角蕨属的分类和系统演化研究提供孢粉学的资料。     

耳蕨属一新组——新生耳蕨组

描述了耳蕨属一新组——新生耳蕨组Sect．Neopolystichum Ching。小羽片背面具披针形小鳞片 使得新生耳蕨组显著区别于后生耳蕨组Sect．Metapolystichum Tagawa(emend．Zhang＆Kung,1996)。 本文对新生耳蕨组进行了分类学研究,共记载本组植物7种,并给出了各种植物的地理分布。认为九州 耳蕨P．kiusiuense Tagawa是大叶耳蕨P．grandifrons C. Chr．的一异名,二尖耳蕨P.biaristatum(Bl．)Moore极有可能并不分布于喜马拉雅、中南半岛、缅甸和云南。     

中国水蕨属孢子形态及其系统学意义的研究

利用扫描电镜和透射电镜技术对我国产水蕨属2种的孢子形态进行了观察,对2种的形态结构进行了描述。本属孢子是同型孢子蕨类植物中最大的孢子,三裂缝,肋状纹饰,由外壁形成纹饰的轮廓;具较薄的周壁,在高倍放大的情况下呈颗粒或杆状,我们从孢子形态角度,支持水蕨作为一个独立的科,它与海金沙科的非洲蕨属（Mohria)的亲缘关系较近,是介于海金沙科和裸子蕨科之间蕨群。     

四川耳蕨属生耳蕨组的分类研究

记载了四川产耳蕨属后生耳蕨组植物９种，其中新种１个，四川新种１个，四川新分布５个，并有新异名７个。本文还对国产有关种类的分类问题进行了讨论。     

中国蕨科植物的孢子形态

中国蕨科９属２１种孢子形态的ＳＥＭ观察结果表明,孢壁纹饰是一个稳定的遗传性状,不受植株分布地区,海拔高度,孢子成熟度以及植株叶片的局部变异的影响,属间孢壁纹饰差异显著,为本科分类提供了孢子形态的依据。孢粉学上区分的类型与植物形态上划分的属相一致。ＬｅｐｔｏｌｅｐｉｄｉｕｍＨｓｉｎｇｅｔＳＫＷｕ具有明显的孢壁纹饰特征,从孢粉学角度看划分为一独立属是成立的,本文还讨论了中国蕨科９属间可能的进化路线。     

中国蕨类植物孢子形态的研究Ⅲ.金星蕨科1.毛蕨属

利用扫描电镜对中国产毛蕨属51种植物孢子形态进行了研究。结果表明：该属孢子为单裂缝,两侧对称,极面观为椭圆形,赤道面观为肾形,由周壁形成表面纹饰。表面纹饰可分为3种类型：(1)周壁具流苏状的翅状纹饰,表面有突起或穿孔,有19种属于此类型;(2)鸡冠状纹饰,有11种属于此类型;(3)刺状纹饰,有10种属于此类型。另外有11种具有上述纹饰的混合纹饰,被认为是中间类型。孢子的形态特征可作为该属的分类学和孢粉学研究的资料。     

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.