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1.
本变种小叶边缘具缘毛,聚伞花序单生叶腋,有时成对簇,通常3-4次二歧分枝,花序梗短于少为长于或等长于叶柄,花冠管较短,长6-7mm,内面近中部具一环白色长毛,核果较小.长6-7mm,直径5-6mm。  相似文献   

2.
合格发表莎草科-新变种-短多穗扁莎草Pycreus polystachyos(Rottb.)P.Beaiv.var.brevispiculatus How ex Y F.Deng.该变种与原变种Pcreus polystachyos(Rottb.)P.Beauv.vat.polystachyos的区别在于秆高8~15 cm,辐射枝极短或近无,小穗多数,簇生成头状,长4~7 mm,具6~14朵花,鳞片褐色或黄褐色.  相似文献   

3.
生于山坡旷野,小溪边,路旁,沟坎上。本变种与原变种的主要区别在于掌状复叶,小叶片5~9,通常为7,边缘具粗锯齿,两  相似文献   

4.
描述了泰国雨久花属Monochoria C.Presl一新变种:窄叶鸭舌草M.vaginalis var.angustifolia G.X.Wang。该新变种与原变种鸭舌草M.vaginalis var.vaginalis都具有类似的总状花序,但前者的叶片为窄披针形,3-7×0.3-2.0cm,叶片宽长比在0.1-0.4之间,叶基部裂片最长不超过2mm,总状花序具花3-7朵,而原变种鸭舌草的叶片较宽,为卵心形或心形,4-9×2-8cm,叶片宽长比在0.5-0.95之间,叶基部裂片最长可达到2cm,总状花序  相似文献   

5.
钱义咏 《植物研究》1998,18(4):398-399
本变种和原变种的区别在于:秆高30-50cm,具4-6节,叶舌长1-2mm,顶端齿裂,叶片长2-10cm,宽2-4mm,圆锥花序稍疏松,长8-15cm,宽1.5-3cm,分枝每节1-5枚簇生,小穗长2.5mm,绿紫色,第二颖长2.3mm,外稃长2.4-2.5mm,内稃长约为外稃的2/3。  相似文献   

6.
报道了云南报春花属一新变种,即长萼铁梗报春Primula sinolisteri Balf. f. var. longicalyx D. W. Xue & C. Q. Zhang。新变种与原变种的不同之处在于:花冠喉部具环状附属物,外面无毛,花萼与冠筒近等长,长7-10 mm。  相似文献   

7.
本文对来自青海省异极藻属和桥弯藻属(硅藻门)的三个新变种进行描述,它们是:橄榄异极藻短纹变种(Gomphonema olivaceum (Lyngbye) Kuetzing var. brevistriatum Li Y. L. et Shi, var. nov.);十字异极藻矩形变种(Gomphonema staurophorum (Pant.) Cleve-Euler var oblongum Li Y. L. et Shi, var. nov)和亚贝桥弯藻具点变种(Cymbella yabe Skvortzow var. punctata Li Y. L. et Shi, var. nov).    相似文献   

8.
甘肃棘豆系新系Sect. Mesogaea Bunge Ser. Kansuenses C. W. Chang, ser. nov. Planta magna. Foliola 8—14—juga, 7—13 (—25) mm longa, 3—gmm lata. Racemus longus, densior; calyx tubulosus, 8—14mm longus;flos magnus, corolla 11—17mm longa, flava, carinae mucro c. 1mm longus. Typus nominis seriei:Oxytropis kansuensis Bunge Species 3 et Varietas unica, septentrionalis, boreali-occidentalis et australi-occidentalis Sinae incolae. 植株高。小叶8—14对,长7—13(—25)mm,宽3—9mm。总状花序长,花排列较密;花萼筒状,长8—14mm;花大,花冠长11—17mm,黄色,龙骨瓣的喙长约1mm。系名模式:甘肃棘豆Oxytropis kansuensis Bunge。本系有3种,1变种,分布于我国华北、西北和西南部。1.白花棘豆新变种  相似文献   

9.
HPLC法测定牡荆中牡荆素的含量   总被引:1,自引:1,他引:0  
建立了牡荆中牡荆素含量的高效液相色谱测定方法,对牡荆资源进行评价,为牡荆的质量标准的建立提供参考.样品采用超声波提取法提取,色谱柱为菲罗门柱(5 μm,250 mm×4.6 mm),流动相为甲醇-水溶液(4∶6),流速为1.0 mLmin-1,检测波长为340 nm,进样量为5 μL,在柱温30 ℃时对牡荆中牡荆素的含...  相似文献   

10.
周杰  陈俊愉 《植物研究》2010,30(6):649-650
报道了中国菊属(Chrysanthemum)一新变种——阔叶毛华菊(Chrysanthemum vestitum(Hem sl.)Stapf.var.latifolium J.Zhou et J.Y.Chen)。本变种与模式变种的区别在于直立生长,并且较多分枝,叶较狭,卵状披针形或匙形,长4~6 cm,宽2~3 cm。花序直径较原种为小,约3.5~4.5 cm。主要分布于湖北宜昌、河南伏牛山山脉。抗旱性较原变种强。而主要原产于安徽西部大别山麓之模式变种则铺散生长,较少分枝,叶圆形、卵圆形,长4~7cm,宽3~5 cm。花序直径较大,约4.5~5.0 cm。  相似文献   

11.
The natural susceptibility of 131 Yersinia strains of Y. frederiksenii (n=38), Y. intermedia (n=48), Y. kristensenii (n=26) and Y. rohdei (n=19) to 70 antibiotics was tested. Minimum inhibitory concentration (MIC) values were determined with a microdilution procedure in IsoSensitest broth (all strains) and cation-adjusted Mueller Hinton broth (some strains). All species were naturally sensitive or sensitive and of intermediate susceptibility to tetracyclines, aminoglycosides, acylureidopenicillins, numerous cephalosporins, carbapenems, aztreonam, quinolones, chloramphenicol, folate-pathway inhibitors, nitrofurantoin, and fosfomycin. Uniform natural resistance was found with penicillin G, oxacillin, several macrolides, lincosamides, streptogramins, glycopeptides, rifampicin and fusidic acid. Species-specific differences in susceptibility affecting clinical assessment criteria were seen with aminopenicillins (in the presence and absence of beta-lactamase inhibitors), ticarcillin and some cephalosporins. Major medium-dependent susceptibilities were found with fosfomycin. beta-Lactam MIC susceptibility patterns suggested that most strains of the species tested produce both class A and class C (AmpC) beta-lactamases that are characteristic for the species. The present study describes a database concerning the natural susceptibility of some Y. enterocolitica-like species to a wide range of antibiotics, which can be applied to validate forthcoming antibiotic susceptibility tests of these strains and might contribute to their identification. An evaluation of 30 biochemical tests that secured phenotypic identification to the Yersinia species level is presented.  相似文献   

12.
I.C.Y     
《CMAJ》1965,92(3):136
  相似文献   

13.
The genus Yersinia is composed of 11 species, of which three (Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica) have been exhaustively characterized. The remaining eight species (Y. frederiksenii, Y. intermedia, Y. kristensenii, Y. bercovieri, Y. mollaretii, Y. rohdei, Y. ruckeri, and Y. aldovae) have not been studied extensively and, because of the absence of classical Yersinia virulence markers, are generally considered to be nonpathogenic. However, recent data suggest that some of these eight species may cause disease by virtue of their having virulence factors distinct from those of Y. enterocolitica. These data raise intriguing questions about the mechanisms by which these species interact with their host cells and elicit human disease.  相似文献   

14.
Acid phosphatase, esterases, and glutamate and malate dehydrogenases of 192 strains of Yersinia enterocolitica, Y. intermedia, Y. aldovae, Y. frederiksenii, Y. kristensenii and Y. pseudotuberculosis were analysed by horizontal polyacrylamide agarose gel electrophoresis and by isoelectrofocusing in thin-layer polyacrylamide gels. The six species were clearly separated from each other by their distinct enzyme electrophoretic polymorphism. For Y. enterocolitica, the strains of biotype 5 were differentiated from the other biotypes by the mobility of glutamate dehydrogenase. For Y. frederiksenii, six zymotypes were delineated by pI and by the mobility of the enzymes. Variation in number or mobility of esterases within each species could represent a marker for epidemiological and ecological analyses. A linear relationship was obtained between the mean genetic diversity coefficient of enzymes and the mean percentage DNA-DNA relatedness of Y. intermedia, Y. aldovae, Y. enterocolitica and Y. frederiksenii.  相似文献   

15.
Two steroidal glycosides were isolated from the rhizome of Aspidistra leshanensis K. Y. Lang et Z. Y. Zhu. Their structures were established as 5-O-β-D-glucopyranosyl-convalla- genin-B and aspidistrin on the basis of chemical and spectral evidences. Diosgenin, isonarthogenin, convallagenin-B, β-sitosterol and a sapogenin with three hydroxyls were obtained from the acid-treated n-BuOH extract.  相似文献   

16.
四川蜘蛛抱蛋的甾体皂甙   总被引:5,自引:0,他引:5  
从四川蜘蛛抱蛋(Aspidistra sichuanensis K。Y。Lang et Z。Y。Zhu)根状茎中分离得到三个甾体皂甙,经光谱和化学方法分别鉴定为22-甲氧基-5β-呋喃甾烷-1β,3β,4β,5β,26-五羟基26-O-β-D吡喃葡萄糖甙(1),蜘蛛抱蛋皂甙(2)和原蜘蛛抱蛋皂甙(3)。(1)是一个呋喃甾醇型单糖链的新皂甙,(3)是本植物的主要皂甙。  相似文献   

17.
18.
本文发表了一苏铁属新种,即秀叶苏铁,对其特征进行了阐述。  相似文献   

19.
Five neuropeptide Y receptors, the Y1-, Y2-, Y4-, Y5- and y6-subtypes, have been cloned, which belong to the rhodopsin-like G-protein-coupled, 7-transmembrane helix-spanning receptors and bind the 36-mer neuromodulator NPY (neuropeptide Y) with nanomolar affinity. In this study, the Y2-receptor subtype expressed in a human neuroblastoma cell line (SMS-KAN) and in transfected Chinese hamster ovary cells (CHO-hY2) was characterized on the protein level by using photoaffinity labeling and antireceptor antibodies. Two photoactivatable analogues of NPY were synthesized, in which a Tyr residue was substituted by the photoreactive amino acid 4-(3-trifluoromethyl)-3H-diazirin-3-ylphenylalanine ((Tmd)Phe), [Nalpha-biotinyl-Ahx2,(Tmd)Phe36]NPY (Tmd36), and the Y2-receptor subtype selective [Nalpha-biotinyl-Ahx2,Ahx5-24,(Tmd)Phe27]N PY (Tmd27). Both analogues were labeled with [3H]succinimidyl-propionate at Lys4 and bind to the Y2-receptor with affinity similar to that of the native ligand. A synthetic fragment of the second (E2) extracellular loop was used to generate subtype selective antireceptor antibodies against the Y2-receptor. Photoaffinity labeling of the receptor followed by SDS-PAGE and detection of bound radioactivity and SDS-PAGE of solubilized receptors and subsequent Western blotting revealed the same molecular masses. Two proteins correspondingly have been detected for each cell line with molecular masses of 58 +/- 4 and 50 +/- 4 kDa, respectively.  相似文献   

20.
Neuropeptide Y (NPY) is a 36-amino acid neuropeptide that exerts its activity by at least five different receptor subtypes that belong to the family of G-protein-coupled receptors. We isolated an aptamer directed against NPY from a nuclease-resistant RNA library. Mapping experiments with N-terminally, C-terminally, and centrally truncated analogues of NPY revealed that the aptamer recognizes the C terminus of NPY. Individual replacement of the four arginine residues at positions 19, 25, 33, and 35 by l-alanine showed that arginine 33 is essential for binding. The aptamer does not recognize pancreatic polypeptide, a highly homologous Y4 receptor-specific peptide of the gut. Furthermore, the affinity of the aptamer to the Y5 receptor-selective agonist [Ala(31),Aib(32)]NPY and the Y1/Y5 receptor-binding peptide [Leu(31),Pro(34)]NPY was considerably reduced, whereas Y2 receptor-specific NPY mutants were bound well by the aptamer. Accordingly, the NPY epitope was recognized by the Y2 receptor, and the aptamer was highly similar. This Y2 receptor mimicking effect was further confirmed by competition binding studies. Whereas the aptamer competed with the Y2 receptor for binding of [(3)H]NPY with high affinity, a low affinity displacement of [(3)H]NPY was observed at the Y1 and the Y5 receptors. Consequently, competition at the Y2 receptor occurred with a considerably lower K(i) value compared with the Y1 and Y5 receptors. These results indicate that the aptamer mimics the binding of NPY to the Y2 receptor more closely than to the Y1 and Y5 receptors.  相似文献   

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