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1.
绞股蓝属(Gynostemma)一新种   总被引:3,自引:0,他引:3  
薛祥骥  徐火亮 《植物研究》1995,15(4):447-449
本文发表了浙江绞股蓝属一新种,即小果绞股蓝GynostemmazhejiangenseX.J.Xue,sp.nov.(Subgen.Gynostemma)。  相似文献   

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喙果绞股蓝黄酮类化合物的分离及结构测定   总被引:3,自引:0,他引:3  
从喙果绞股蓝(Gynostemma yixingenseC.Y.WuetS.K.Chen.)的茎叶分离到7种化合物:喙果黄素(yixingensin)(I)、山奈酚(kaempferol)(I)、商陆素(ombuin)(Ⅲ)、商甙(om-buoside)(Ⅳ)、槲皮素(quercetin)(V)、异鼠李素(isorhamnetin)(Ⅵ)和硬脂酸(Ⅶ)。其中,喙果黄素为新的黄酮甙,通过光谱分析及化学反应鉴定为商陆素一3-O-β一D一葡萄糖成。  相似文献   

3.
竹叶吉祥草(鸭跖草科)的核型研究   总被引:1,自引:0,他引:1  
杨亲二  罗毅波  洪德元   《广西植物》1994,14(2):170-173
本文对鸭跖草科的竹叶吉祥草(Spatholirionlongifolium(Gagnep.)Dunn)进行了染色体研究.其染色体大型,数目为2n=20;核型公式为2n=4sm+14st+2t(sat).为首次报道。这支持了竹叶吉祥草属和竹叶子属是两个亲缘关系较近,但同时又是两个分明不同的属的观点。  相似文献   

4.
四种风毛菊属植物的核型研究   总被引:14,自引:0,他引:14  
黄运平  尹祖棠   《广西植物》1994,14(4):357-360
本文首次报道产于我国华北地区风毛菊属(SaussureaDC.)4种植物的染色体数目和核型。四个种的染色体数目均是2n=26,都是2倍体。它们的核型是:糠风毛菊(S.Paleata)Zn=2x=26=18m+6sm+2st,属2B型,华北风毛菊(S.mongolica)Zn=2x=26=14m+4sm+8st,属2B型;狭苞凤毛菊(S.dielsiana)Zn=2x=26=8m+12sm+6st,属2C型;银背凤毛菊(S.nivea)2n=2x=26=18m+6sm+2st,属2A型。染色体中均未发现随体。  相似文献   

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绞股蓝抗肿瘤的药理和临床研究进展潘扬,魏菁(南京中医药大学,南京210029)绞股蓝Gynostemmapentaphyllum(Thunb)Mak,为葫芦科多年生草质藤本,又名七叶胆。全世界绞股蓝属植物约有13种,中国有13种,其中7种为我国所特有...  相似文献   

6.
绞股蓝雌雄种群觅源行为和繁殖对策比较   总被引:6,自引:0,他引:6  
绞股蓝(Gynostemma pentaphyllum)雌雄异株,种群性比偏雄。作者利用比较生态学方法,从行为生态学角度探讨相同生境中绞股蓝雌雄种群的觅源行为和繁殖对策,得到如下初步结果和结论:(1)绞股蓝雄性种群的主枝生物量比显著大于雌性种群,这意味着雄性种群的营养繁殖投资显著增加,而两性种群在其它结构中的生物量分配无显著差异;(2)雌性种群的叶面积比和单位叶面积比雄性种群显著增加,这与两性种群  相似文献   

7.
稀有濒危植物珊瑚菜的染色体特征及其演化地位   总被引:2,自引:1,他引:1  
刘启新  惠红  刘梦华   《广西植物》1999,19(4):344-348
首次分析了珊瑚菜( Glehnia littoralis) 根尖体细胞染色体组型。其核型公式为2 n = 22= 18M + 4Sm (2Sat) , 核型不对称性属于2A 型。据此讨论了该属在我国伞形科稀有濒危单型属和当归亚族中的演化地位。  相似文献   

8.
赵汉雄 《化石》2001,(3):28-30
能追溯种形成全过程的实例仅1例 ,为C.L.赫斯金斯(1931)报导的大米草新种(Spartinatonnsencli,2n=126),它由欧洲本地大米草(S.stricta,2n=56)与美洲大米草(S.alterniflom,2n=70)自然杂交 ;杂合子本不育 ,但单倍体植株生长时经自然发生的染色体加倍 ,克服了减数分裂时染色体配对困难 ,从而得到能独立遗传的染色体组 ,成为新物种。此例虽为孤证 ,但学理清楚 ,可重复实验 ,影响极大。已普查了显花植物2723属15193种 ,多倍体种数有7596种(高达50…  相似文献   

9.
在华南,迄今只在泥盆纪地层中发现豆石介类(leperditiids)。由于它们均具有下垂“V”字型肌痕且此肌痕随时间的推移不断向下延伸,被考虑是豆石介类中一独立的演化支系,并归一新族:Sinoleperditiini。此族,在华南地区含2属和6亚属:Sinoleperditia(Sinoleperditia)Wang,1989,S.(Pseudobriartina)subgen.nov.,S.(Yaosuoleprditia)subgen.nov,Paramoelleritia(Paralaperditia)Sun,1978,P.(Paramoelleritia)Wang,1976和P.(Brevilaperditia)subgen.nov.。重点探讨了此族的起源,演化型式及趋势和绝灭。指出“V”字型或下垂“V”字型肌的功能与闭壳肌可能是异曲同功,起闭壳作用;放射和横向条纹可能是闭壳肌和下垂“V”字型肌频繁收缩所致而不是血管束的痕迹,并可能具有排泻作用;DalelinaSun,1978是ParaleperditiaSun,1978的同物异名;ParaeoloperditiaAdachietIgo,1980属  相似文献   

10.
华南泥盆纪分形类豆石分类一新族Sinoleperditiini   总被引:5,自引:1,他引:5  
王尚启 《古生物学报》1994,33(6):686-719
在华南,迄今只在泥盆纪地层中发现豆石介类(leperditiids)。由于它们均具有下垂“V”字型肌痕且此肌痕随时间的推移不断向下延伸,被考虑是豆石介类中一独立的演化支系,并归一新族:Sinoleperditiini。此族,在华南地区含2属和6亚属:Sinoleperditia(Sinoleperditia)Wang,1989,S.(Pseudobriartina)subgen.nov.,S.(Yaosuoleprditia)subgen.nov,Paramoelleritia(Paralaperditia)Sun,1978,P.(Paramoelleritia)Wang,1976和P.(Brevilaperditia)subgen.nov.。重点探讨了此族的起源,演化型式及趋势和绝灭。指出“V”字型或下垂“V”字型肌的功能与闭壳肌可能是异曲同功,起闭壳作用;放射和横向条纹可能是闭壳肌和下垂“V”字型肌频繁收缩所致而不是血管束的痕迹,并可能具有排泻作用;DalelinaSun,1978是ParaleperditiaSun,1978的同物异名;ParaeoloperditiaAdachietIgo。  相似文献   

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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   

16.
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   

17.
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.  相似文献   

18.
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  相似文献   

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