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1.
A new triterpenoid, 11a.O.trans-p-coumaroyltaraxerol (1), along with 11 known triterpenoids, taraxerone (2), taraxerol (3), 2α,3β,23,24-tetrahydroxyolean-12-en-28-oic acid (4), oleanolic acid (5), β-amyrin (6), 3β,23-dihydroxylursan-12-en- 28-oic acid (7), 2α,3β-dihydroxyursan-12-en-28-oic acid (8), 2α,3β,23-trihydroxyursan-12-en-28-oic acid (9), 2α,3β,24- trihydroxyursan-12-en-28-oic acid (10), u rsolic acid (11), and 3-O-acetylursolic acid (12), was isolated from Craibiodendron henryi W. W. Smith (Ericaceae). The structures of these compounds were elucidated on the basis of spectral evidence. Antioxidant activity and vasodilator effect of compound 1 were assessed.  相似文献   

2.
Four diterpenoids have been isolated from the dried leaves of Rabdosia macrocalyx var. juihua Z. W. Xue et X..W. Wang. Three of them were shown to be known diter- penoids, excisanin A, excisanin B and macrocalyxin A, while the one, a new kauranetype diterpene, was named jiuhuanin A. On the basis of physico-chemical constants, spectroscopic analysis of the new compound and properties of its derivatives, the structure of the compound was identified as (1). Jiuhuanin A was shown to have cytotoxicity in vitro against cultures of Hela cell and A549 cells.  相似文献   

3.
指定了卧龙乌头Aconitum wolongense W.T.Wang的后选模式。  相似文献   

4.
云南贡山异叶苣苔属(苦苣苔科)一新种   总被引:2,自引:0,他引:2  
贡山异叶苣苔 新种 图 1WhytockiagongshanensisYinZ .WangetH .Li,sp .nov .Fig .1 .AffinisW .tsiangianae (Hand . Mazz.)A .Weber,aquasepalislatioribus,corol  相似文献   

5.
根据对单叶黄荆(Vitex simplicifolia)模式标本的研究,结合在其模式产地的野外调查,发现单叶黄荆与黄荆(V.negundo)并无本质区别,不宜作为独立的种,但其叶片为单叶而且比较稳定,将其降级并组合为黄荆的变种。  相似文献   

6.
发现卧龙乌头Aconitum wolongense W.T. Wang的模式实际上包含两种植物,即毛果甘青乌头A. tanguticum (Maxim.)Stapf.var.trichocarpum Hand.-Mazz.和展毛大渡乌头A.franchetii Fin.et Gagnep.var.villosum W.T. Wang,故将该种予以归并。  相似文献   

7.
The impact is discussed here of some experiments by W.A. Aronld and coworkers on photosynthetic research, specifically on that at the Leiden Biophysics Department. These experiments involved the following topics: photosynthetic unit and electronic excitation transfer to a reaction center, chlorophyll luminescence and photosynthesis, and unexpected experimental results as a source of discoveries.  相似文献   

8.
An examination of the type specimen of Aconitum jiulongense W. T. Wang has shown that it should be reduced to synonymy of A. carmichaeli Debx.  相似文献   

9.
10.
根据对单叶黄荆(Vitex simplicifolia)模式标本的研究,结合在其模式产地的野外调查,发现单叶黄荆与黄荆(V.negundo)并无本质区别,不宜作为独立的种,但其叶片为单叶而且比较稳定,将其降级并组合为黄荆的变种。  相似文献   

11.
1971年,N.Ulzijkhutag根据采自阿拉善戈壁(=Bordzon-Go-bi)的标本(1970-07-29,V.I.Grubov,N.Ulzijkhutag et G.Tserendalzhid,无号)发表新种Oxytrops grubovii,并以此建立新组Oxytropis subgen.Traganthoxytropis sect.Monan-thos;1987年,G.P.Yakovlev将O.grubovii归入海绵豆属Spongiocarpella;1988年,张振万同意N.Ulzijkhutag的意见,并根据刺垫棘豆之龙骨瓣无喙等特征将Ulzijkhutag的刺  相似文献   

12.
桂西和黔南中三叠世珊瑚   总被引:1,自引:0,他引:1  
文内描述中三叠世安尼阶(Anisian)珊瑚化石分别采自桂西田阳板纳组和黔南贵阳青岩青岩组。板纳组珊瑚群中建立Pentasmilia guangxiensisgen.etsp.nov.,该新属种有5条第一周期原生隔片甚至有5条第二周期后生隔片,以此不同于有6条第一周期原生隔片和有6条第二周期后生隔片的石珊瑚类(scleractinians)的珊瑚。产于板纳组的另一新属种Radiophyllia astylatusgen.etsp.nov.,其隔片的排列格式与前人归纳的隔片周期插入示意图甚似,但它却发生在中生代最早期(Anisian)珊瑚的骸体内。文中还对青岩组的Pamiroseris silesiaca作了重新描述。  相似文献   

13.
20 0 3年在沈阳的三裂叶豚草 (AmbrosiatrifidaL .)上发现了苍耳柄锈菌三裂叶豚草专化型 (PucciniaxanthiiSchwein .f.sp .ambrosia trifidaeS .W .T .Batra) ,这是在我国三裂叶豚草上发现的一种新病菌。试验采用扫描电镜和透射电镜对该锈菌的冬孢子和吸器的形态结构进行了观察。  相似文献   

14.
The monotypic subgenus Acanthoxytropis C. W. Chang of Oxytropis was established in 1988 based on the species O. grubovii Ulzij., which is mainly characterized by solitary flower, coriaceous pods, and keels without beak, while these are typical character of the genus Chesneya Lindl. ex Endl. The present author checked authoritative specimens and assigns it C. macrantha Cheng f. ex H. C. Fu.  相似文献   

15.
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17.
采用光谱法和胰酯酶分解法对大果木姜子油酯中分得的结晶C—I组成进行了分析,结果表明C—I是由11种甘油三酯组成。其中2-位为月硅酸的甘油三酯占91.80%,1,3-位脂肪酸主要为癸酸和月桂酸,甘油三酯的组成中,CLC占62.24%,LLC占24.50%。  相似文献   

18.
《Journal of bryology》2013,35(2):239-242
Abstract

Six bryophyte species were investigated: Plagiochila spinulosa, Hylocomium splendens, Scorpiurium circinatum, Tortula ruraliformis, Rhacomitrium aquaticum and Andreaea rothii. Of these, all except A. rothii showed clear evidence of seasonal variation in desiccation tolerance, as measured by net assimilation following 24 h remoistening.

(2) In general these species showed low desiccation tolerance in autumn (October) and winter (January) and increased tolerance in spring and summer. Hylocomium splendens was a partial exception in showing relatively high tolerance in January and little change from then until July.

(3) On the whole, the seasonal pattern of desiccation response accords well with what might be expected from conditions in the habitats of the plants. The results are briefly discussed in relation to distribution of rainfall and some microenvironmental factors, and compared with some data from the literature.  相似文献   

19.
Pinus halepensis forests of N.W. Algeria are subjected to frequent fires. During the fire the aboveground parts of plants are completely burned but only a few species are killed. Most perennial herb and shrub species survive owing to their underground organs and regenerate vegetatively in the next moist period. The semi-shrubs regenerate both vegetatively and from seeds. The most intensive growth of the shrub layer occurs during the first 2 years and in the 5th year, it reaches a height of 1–1.5 m. Pinus halepensis is completely killed by the fire and it regenerates from seeds only. The regeneration is retarded during the first 2–3 years, apparently by competition of the rapidly developing shrubs and semi-shrubs with P. halepensis. In the following years, there is a more rapid increase in both density and height, although by the 5th year after fire, the height does not exceed 0.5 m. The young trees overtop the shrub layer between 10 and 15 years after fire. The increase in density and cover supress the lower layers, in particular the herb layer. The reduction in density of trees in the following decades enables the herb layer to reconstitute its composition and cover.This process of regeneration resembles forest growth cycles rather than a secondary succession. The shrub and herb layers maintain their identity as they are mostly formed of the same individuals as before the fire; they merely regenerated their aboveground organs. Only the tree layer regenerates anew after the fire.  相似文献   

20.
阿当耳蕨 新种 图1 Polystichum adungense Ching et Fraser-Jenkins sp. nov. in sched. Species affinis P. rhomboidei Ching, sed pinnis herbaceis, utrinque paleis fibrosis dif-fert. Tota planta 12—14 cm. alta. Rhizoma erectum, paleis brunneis, lanceolatis obtectum.  相似文献   

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