首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
一、甘松与甘松油简介甘松属败酱科甘松香属多年生草本植物。分为中华甘松(Nardostachys Chinensis Batalin)和长匙甘松(Nardostachys jtamansi),是一种珍贵的经济植物,其主要分布我国四川、云南、甘肃、青海、西藏等省(区),以及印度、尼泊尔等国家。生长于阴湿山坡及湿  相似文献   

2.
徐炳声  刘琰  陈铁山   《广西植物》1986,(Z1):95-98
假百合,Notholirion bulbiliferum (Lingelsh.) Stearn [N.hyacinthinum (Wils.) Stapf]是百合科假百合属,Notholirion Wall.ex Boiss.的多年生草本植物,产于我国陕西、甘肃、四川、西藏和云南等省区;尼泊尔、锡金、不丹和印度也有分布。假百合陕西民间叫“太白米”,是一种药用植物。 假百合属共4种,做过染色体计数者3种。本文首次报道了假百合的染色体数目,并做了核型分析,旨在与百合属Lilium L.的核型作一比较,为探讨这两属间的亲缘关系提供必要的细胞学资料。  相似文献   

3.
在甘肃中南部设置12个样区,对该地区原尾虫的物种多样性进行了研究。发现原尾虫11种,隶属于2目6科7属。其中包括1个甘肃新记录属、4个甘肃新记录种和1个未定名种。古蚖科Eosentomidae、檗蚖科Berberentulidae为优势类群。华山蚖Huashanentulus huashanensis为广布种;檗蚖科Berberentulidae有2属3种;古蚖科Eosentomidae有3属7种,占甘肃原尾虫总数的44%;始蚖科Protentomidae有1属1种;夕蚖科Hesperentomidae有1属2种;日本蚖科Nipponentomidae有1种,中华雅娃蚖Yavanna sinensis是甘肃的新记录种;蚖科Hesperentomidae有1属2种,包括1个华山蚖属未定名种Huashanentulus sp.,只分布在临夏太子山自然保护区。对甘肃原尾虫区系进行了分析,结果显示:古北界种类占总数的20%,东洋界物种占53.3%,广布种类占总数的26.7%。  相似文献   

4.
甘肃棘豆属于疯草,有毒,为豆科棘豆属多年生草本植物,严重影响我国西南牧区的牲畜安全。植物内生细菌是指定殖在植物组织内部但不引起明显病害症状的细菌,它具有许多生物学功能作用。本文以甘肃棘豆种子为研究对象对其内生细菌进行了分离,并利用形态观察、生化试验等方法进行了初步鉴定。实验共分离到3株菌株,2株杆菌,1株球菌。所得菌株为后续研究甘肃棘豆内生细菌与甘肃棘豆所含毒素的相互关系提供了细菌菌株来源。  相似文献   

5.
封面说明     
布袋兰[Calypsobul bosa(L.)Oakes],隶属于兰科,兰亚科,树兰族,布袋兰属,该属仅1~2种。为地生兰,常生于云杉林或其他针叶林下,在四川、甘肃,其生长地海拔可达3200m。为多年生草本植物,地下具假鳞茎,偶见珊瑚状根状茎。  相似文献   

6.
苦豆子是豆科、槐属的一种多年生旱生草本植物,主要分布于中国内蒙古、河北、山西、河南、陕西、宁夏、甘肃、青海、新疆、西藏等地,具有重要的生态价值、药用价值和经济价值.通过查阅文献资料,系统总结药用植物苦豆子的研究现状,并于2019~2020年调查了苦豆子的野外自然地理分布区,收集了苦豆子群体水平上的标本、DNA材料和成熟...  相似文献   

7.
甘肃忍冬科植物区系地理   总被引:1,自引:0,他引:1  
对甘肃产忍冬科植物8属59种8变种及3亚种(不包括引种栽培的1属和3种)*进行了统计,并计算甘肃与邻近省的相似性系数,与陕西省的最大,为0.41;而与西藏的为最小,仅为0.14。陇南西部河谷亚热带湿润区和陇南北部暖温带区是甘肃产忍冬科植物种类最为丰富的地区。同时,对甘肃产忍冬科植物进行了属、种分布区类型的划分,属的分布区类型可划分为:旧世界温带分布、温带亚洲分布、东亚分布和中国特有4个类型。种的分布类型可划分为:中国特有、东亚分布、温带亚洲分布和旧世界温带分布。从该科植物在甘肃的分布来看,绝大多数种类都不超过中国4个植物亚区在甘肃的交汇点,与中国植物区划基本相符,并可确切说此交汇点应在兰州的永登县附近。  相似文献   

8.
甘肃悬钩子属系统分类及区系地理研究   总被引:1,自引:1,他引:0  
甘肃省产悬钩子属植物34种、8变种、隶属于3组11亚组,其中5个种为甘肃分布新记录、个新种及1个新变种。本文根据实地调查和标本鉴定,编制了系统检索表,并对甘肃悬钩子属植物区系成分及区系成进行了初步探讨。  相似文献   

9.
严峰  龚大洁  俞诗源 《四川动物》2006,25(2):336-338
调查表明甘肃有两栖类动物24种,其中有尾目3科3属3种,无尾目6科21种.属于古北界的有5种和亚种,属东洋界的有14种,其余5种为两界兼有种.对引起甘肃省两栖类动物种群衰退、变异和灭绝的主要因素进行了初步分析,提出了若干针对甘肃两栖类动物的保护对策.  相似文献   

10.
采用样线法调查了东辽河河岸带草本植物群落,分析了物种多样性特征,利用组平均聚类法和除趋势对应分析(DCA)分别对植物群落进行了分类和排序,探讨了影响东辽河河岸带草本植物群落分布的主要环境因子。结果表明:东辽河河岸带共有草本植物118种,属36科70属,草本植物的物种多样性自上游向下游呈现先增加后降低的变化趋势,而丰富度指数变化规律不显著,这与河流水文特征、河岸土壤基质类型、土壤含水量和人为干扰有关。聚类分析结果显示,东辽河河岸带草本群落可划分为11种类型,其中湿生植物群落占据优势。DCA排序轴与环境因子的相关性分析表明,海拔和河流等级是东辽河河岸带草本植物群落分布的重要影响因子。  相似文献   

11.
12.
13.
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   

14.
15.
16.
17.
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.  相似文献   

18.
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.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

20.
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.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号