大鳞裂峡鲃繁殖生物学特征

2009、2010和2013年在云南省西双版纳自治州勐腊县境内的南腊河共收集大鳞裂峡鲃(Hampala macrolepidota)样本438尾。研究结果表明:大鳞裂峡鲃雌性群体初次性成熟体长228 mm、体重270.3 g,雄性群体初次性成熟体长205 mm、体重172.5 g,对应年龄均为4龄。大鳞裂峡鲃雌、雄繁殖群体的成熟系数年度变化趋势基本一致。成熟系数值在1月、3月、4月呈逐渐增大趋势,5月显著上升,6月达到最高峰,7月急速下降,8月至9月趋于平缓。繁殖活动每年4月开始,一直可持续至10月,主要集中在5~6月。大鳞裂峡鲃雌雄性比为1︰1.19,与鲃亚科其他部分鱼类雌性数量多于雄性的情况相反;繁殖盛期则雌性数量多于雄性。繁殖群体由4~8龄共5个年龄组组成,雌、雄群体均以5龄组所占比例最大。大鳞裂峡鲃属单次产卵鱼类。平均卵径1.18 mm;绝对繁殖力为63 393粒,相对繁殖力为70.04粒/g。与鲃亚科其他部分鱼类比较,大鳞裂峡鲃的卵径相对较小而繁殖力较大。     

柴达木盆地渐新世的鲤科鱼类化石

记述了首次发现于柴达木盆地早渐新世晚期至晚渐新世早期(距今27～29 Ma)的鲤科鱼类化石。材料包括咽骨、咽齿、匙骨、腹鳍骨及一些零散的鳍条。咽骨及咽齿化石与原始鲃亚科鱼类及裂腹鱼亚科裂腹鱼属鱼类的相似;腹鳍骨化石与原始鲃亚科鱼类的更相似。鲃亚科鱼类现今分布于北纬35°以南的亚洲、欧洲南部及非洲北部;裂腹鱼属鱼类分布局限于青藏高原东、南、西面的边缘区域,在柴达木盆地没有分布。柴达木盆地水系现生鱼类仅见适于高寒环境的高度特化等级的裂腹鱼亚科鱼类及鳅科高原鳅属鱼类,鱼类组成与早渐新世晚期至晚渐新世早期的不尽相同。     

中国"四须鲃"类的系统整理

四须鲃属是一个“大口袋”类群。中国的四须鲃实际上分属于至少4个不同的属。通过与Rainboth的分类系统比对之后,对中国四须鲃属鱼类的分类系统重新进行了以下的修订：①保山四须鲃、软鳍四须鲃和异口四须鲃归入新光唇鱼属;②小四须鲃归入盘齿鲃属;③分布于云南的高体四须鲃实为大鳞四须鲃,大鳞四须鲃应归入高须鱼属;④其余四须鲃属鱼类,抚仙四须鲃、常氏四须鲃、太平四须鲃、云南四须鲃、颌突四须鲃(=洱海四须鲃)、鲂形四须鲃、棱四须鲃、后鳍四须鲃和油四须鲃均归入吻孔鲃属。     

山东苔藓植物新记录

该研究通过对采自山东的苔藓植物标本进行鉴定,首次发现裂齿藓[ Dichodontium pellucidum (Hedw.) Schimp.]和粗疣藓[ Fauriella tenuis (Mitt.) Cardot]在山东的分布,这也是昂氏藓科(Aongstroemiaceae)裂齿藓属( Dichodontium Schimp.)和粗疣藓属( Fauriella Besch.)的苔藓植物在山东的首次发现。文中还详细描述了裂齿藓和粗疣藓的形态特征,绘制了墨线图,并进行了相应的讨论。     

刺鲃的食性分析和生长繁殖

刺鲃[Barbodes(spinbarbus)caldwelli(Nichols)]属鲤料,鲃亚科,光倒刺鲃属(附图)。 一、生活习性 在河溪中常发现三、五成群的栖息在底层多乱石的流水中,在大水库静水的情况下,多发现为单一活动,活动水层以底层为主,到表层活动的较少。性较活泼。     

南门峡裂腹鱼亚科鱼类形态相似种的分类学地位——形态趋同进化实例

受高原抬升所致的水系变迁及人类活动的影响,分布于南门峡河流的裂腹鱼亚科鱼类与黄河干支流种群间的基因交流受到长期限制。作为孤立小群体,探讨其分类学地位及其在小生境中的进化机制对了解青藏高原鱼类多样性和物种的形成、进化具有重要意义。本文采用聚合酶链式反应(PCR)和直接测序方法获得了南门峡裂腹鱼亚科鱼类(n=29)及其近缘种(n=19)共48个个体的线粒体DNA(mtDNA)细胞色素b(cytb)基因的全序列(1140bp),并以厚唇裸重鱼和尖裸鲤为外群构建了MP和Bayesian系统进化树。南门峡裂腹鱼亚科鱼类29个个体的序列经排序后,发现有100个(8·77%)多态性位点,共定义了16个单倍型,在系统进化树上分布于截然不同的两个族群中。其中5个单倍型(NMX3、6、7、13、15)与其近缘种花斑裸鲤和青海湖裸鲤形成单系群(MP99%,Bayesian98%),而其余11个单倍型(NMX1、2、4、5、8、9、10、11、12、14、16)与黄河干支流的黄河裸裂尻鱼形成另一个单系群(MP99%,Bayesian99%)。序列差异分析显示,分布于不同族群的南门峡裂腹鱼亚科鱼类之间存在较大的碱基差异(平均为7·42%),显示出种间差异水平,表明分布于南门峡河流的裂腹鱼亚科鱼类可能是花斑裸鲤和黄河裸裂尻鱼形态相似种的复合体。结合青藏高原隆升所致的气候环境变化和高原北部水系变迁的事件,推断形态趋同进化可能导致了南门峡河流裂腹鱼亚科鱼类形态相似种的共存,而小生境自然选择压力是引发适应性形态趋同进化的主要原因。     

野生巴马拟缨鱼肌肉营养成分研究

巴马油鱼, 曾用名巴马穗唇鲃(Crossocheilus bamaensis,Fang),学名为巴马拟缨鱼(Pseudocrossocheilusbamaensis (Fang)),鲤形目(Cyprinformes),鲤科(Cyprinidae),野鲮亚科(Labeoninae),拟缨鱼属(Pseudocrossocheilus)。巴马穗唇鲃主要分布于西江水系的广西巴马、天鹅、都安、来宾,贵州平塘、罗甸、望谟等地,于每年5、6月的洪水期繁殖,以固着藻类为食。       

湖北楠木属一新变种——裂叶白楠

报道了楠木属一新变种——裂叶白楠[Phoebe neurantha(Hemsl.)Gamble var.lobophylla Y.J.Fei]。该变种(裂叶白楠)与白楠[Phoebe neurantha(Hemsl.)Gamble]的区别在于叶片中部到距叶尖1/3处叶片宽度陡然变窄,若有强健侧脉支持则叶片发生裂刻,若无,叶片变狭长,两种变异均存在叶片先端变狭,且呈狭长弯镰状;叶脉下陷更深,侧脉与主脉的夹角逐渐变大,最终呈羽状分布,且越靠近叶尖侧脉分布越密集,单侧侧脉数为25~40;裂刻处叶缘无革质化,粗糙且常具细毛。且这些性状能够稳定遗传给下一代。凭证模式标本现藏于武汉植物园标本馆(编号Y.J.Fei002,HIB)。     

内蒙古被子植物新资料

报道了内蒙古3个新分布记录属:鼠尾草属(Salvia L.)、单蕊草属(Cinna L.)、裂稃茅属(Schizachne Hackel);3个新分布记录种:荫生鼠尾草(Salvia umbratica Hance)、红果龙葵(Solanum villosum Miller)、单蕊草[Cinna latifolia (Trev.) Griseb.];1个新记录亚种: 裂稃茅[Schizachne purpurascens (Torrey) Swallen subsp.callosa (Turcz.) T.Koyama & Kawano];1个黄芪属(豆科)新变型--皇甫川黄芪.     

云南石林洞穴金线鲃一新种(鲤形目,鲤科)

2006年4月12日和18日作者于云南省石林县石林镇落水洞(蝙蝠洞)地下伏流(属珠江水系)采集到金线鲃属鱼类标本9尾,经鉴定为1新种.新种被命名为宽角金线鲃Sinocyclocheilus broadihornes sp. nov.;以其头上长有一个骨质角状突和体表裸露,仅存侧线鳞等鉴别特征,与犀角金线鲃S.rhinocerous Li et Tao相近,而明显区别于属内的其余种.但新种头上骨质突起为1个等边三角形状的角与后者的犀角型角不同;新种吻端与两鼻孔间有3个突起,呈品字形分布,后者平滑.     

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.