睡莲属植物花粉形态研究

为明确睡莲属植物花粉形态特征,研究利用扫描电镜对18种或品种睡莲属植物的花粉形态特征进行观察,并对花粉形态及其种间亲缘关系进行分析,同时利用离体萌发法对睡莲品种‘彼得’的花粉活力进行测定,为睡莲杂交育种亲本的选择提供依据。结果表明:(1)18种或品种睡莲属植物的花粉均为单粒花粉,形态均为近球体或扁球体,其中巨花睡莲花粉粒最大,体积指数为30.3;埃及白睡莲花粉粒最小,体积指数为19.2。(2)花粉外壁纹饰类型繁多,包括网纹状、小颗粒状、瘤状、小柱状、长条状、微波纹起伏状。(3)根据聚类分析可将18种或品种睡莲属植物分为4个类群,其中Nymphaea亚属与Brachyceras亚属间亲缘关系最近。(4)‘彼得’的花粉离体萌发率高,可达95%以上。研究认为,睡莲属植物的花粉形态特征,特别是花粉萌发沟类型、外壁纹饰等特征可作为睡莲属植物种间分类、亚属间以及种间亲缘关系、系统进化规律的关键证据。     

睡莲微型化栽培试验

睡莲属(Nymphaea)是水生植物睡莲科(Nymphaeaceae)的一个重要属。自古以来成为我国湖、塘、庭园水池中点缀水景的名花。它与荷花一样出污泥而不染,花型秀美,色彩艳丽,花期长,因而赢得了人们的喜爱。为了培育适合城市居民家庭养花的小型睡莲品种,我们从1988年开始进行睡蓬微型化栽培试验,取得了较明显的效果。获得了一个适合家庭阳台种植的盆栽睡莲品     

流感疫苗接种引起发作性睡病

在2009年全球A(H1N1)流感病毒大流行期间,多种A(H1N1)大流行流感疫苗被批准应用。一种以AS03-为佐剂的A(H1N1)大流行流感疫苗(Pandemrix)被应用于47个国家,达3 100万剂。在应用一年后,开始出现接种Pandemrix疫苗所引起的发作性睡病的报道。发作性睡病是一种尚无治疗方法的疾病,主要症状表现是患者在白天常发生不可自控的睡眠。报道首先来自于瑞士,然后丹麦,继而欧洲的许多国家。迄今为止,已有1 300多人因接种Pandemrix疫苗发生了发作性睡病,生产Pandemrix疫苗的葛兰素史克(Glaxo Smith-Kline,GSK)公司已承认了两者间的关联。2015年7月1日,科学转化医学杂志的一篇文章揭示Pandemrix疫苗中的流感病毒核蛋白刺激所产生的抗体可以和人下丘脑泌素受体2发生交叉反应,表明Pandemrix疫苗激发的自身免疫反应是其引起发作性睡病的主因,提示有必要显著减少或去除流感病毒疫苗中的流感病毒核蛋白。     

世界上最小的睡莲——侏儒卢旺达睡莲

正通常说到睡莲,基本上是睡莲科睡莲属(Nymphaea)植物的泛称,根据Flora of China记载,世界睡莲属植物约50种,分布在全球的温带及热带地区,目前主要作为观赏植物而广泛栽培于池沼或庭园水景中。从花色上讲,睡莲属植物可能是水生植物中颜色最为丰富的一类植物,雪白、粉色、黄色、粉红色、玫瑰红色、橙色、蓝色、蓝紫色等等,妖娆万分,让人眼花     

睡菜离体快繁技术的研究

以睡菜的幼嫩茎段为外植体,接种到附加不同浓度激素配比(6-BA/NAA)的MS培养基,诱导睡菜愈伤组织、芽及根的生长。研究发现,外植体在1.0mg/L 6-BA+0.1mg/L NAA+MS的培养基上培养10d,可观察到浅绿色的愈伤组织。愈伤组织转接到4.0mg/L 6-BA+0.3mg/L NAA+MS培养基上2周左右可生成芽。对带芽的愈伤组织再进行诱导生根进而形成完整再生植株,最适根诱导培养基为0.3mg/L 6-BA+1.0mg/L NAA+MS培养基。该实验采用植物离体快繁技术成功建立了睡菜再生体系,为睡菜种苗规模化奠定了技术基础。     

睡莲无性繁殖栽培技术初探

本文介绍了睡莲属(Nymphaea L.)3个种(延药睡莲N.stellata,黄睡莲N.mexicana,白睡莲N.alba[1])的无性繁殖栽培试验结果,探讨了睡莲无性繁殖栽培技术,为睡莲属植物的快速繁殖奠定了良好的基础。     

广州地区3种睡莲花开放的日变化规律分析

为了解睡莲属(Nymphaea)植物开花的日变化规律,以广州华南农业大学湿地公园的睡莲属植物为对象进行观察和分析。结果显示,晚上开花类的热带睡莲,其日变化是花朵于晚上开放并持续至第二天上午,白天开花类的热带睡莲和耐寒睡莲,其开放时间为白昼,开放时间因种类不同而有所差异。白天开花的热带睡莲‘独立’(Nymphaea‘Independence’)和耐寒睡莲‘科罗拉多’(Nymphaea‘Colorado’)单朵花期3~4 d,耐寒睡莲墨西哥黄睡莲(N.mexicana)单朵花期2 d,雌雄蕊先后成熟以达到异花授粉的目的,单朵睡莲开放期间雄蕊群呈现不同形态。‘独立’睡莲呈现日出而开,日落则合的开花生物钟,10月至12月,光照时间缩短导致‘独立’睡莲开闭节律缩短。观察结果可为园林水景中睡莲属植物配置提供准确的数据支持。     

救救北京的睡菜

正北京延庆田宋营生长着一种美丽的水生植物——睡菜(Menyanthes trifoliata)。它在此生长了多久,没人知道,恐怕早于任何一个北京人。《北京植物志》甚至也未能收录它。2009年4月林秦文告诉我:田宋营有睡菜!我立即驾车前往观看。它美极了!三言两语无法描述,植物志上的官样描写不足以展现它的魅力。     

三江平原典型沼泽湿地植物种群的生态位

采用Levins 公式,对三江平原典型沼泽湿地植物群落的优势种群生态位宽度和生态位重叠值进行了研究.结果表明：各湿地植物种的生态位宽度排序为漂筏苔草(0.907)>毛果苔草(0.864) >狭叶甜茅(0.855) >小叶章＝睡菜＝球尾花＝二歧银莲花(0.500).毛果苔草、漂筏苔草、睡菜与球尾花之间,以及狭叶甜茅、小叶章与二歧银莲花的生态位重叠值均较高,说明几种植物在同一资源位上出现的频率相近,利用资源的能力相似,在对资源利用上具有一定的竞争性.睡菜与小叶章和二歧银莲花,以及球尾花与小叶章和二歧银莲花的生态位重叠值均为0,表明几种植物适应环境的方式不同.水分是导致湿地植物生态适应性差异的主导因子,植物对环境生态位适应的程度是水分和营养状况等因素共同作用的结果.湿地植物的生态位特征能较好地表征各植物的生态适应性和分布幅度.     

西藏睡菜科一新记录属——莕菜属

报道西藏一个新记录属,是睡菜科(Menyanthaceae)的莕菜属(Nymphoides),并报道该地区的一个新记录种,即莕菜(Nym phoides peltatum(Gmel.)O.Kuntze).     

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.