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1.
中国柽柳科(Tamaricaceae)花粉形态研究及其分类意义的探讨   总被引:17,自引:2,他引:15  
研究观察了中国柽柳科(Tamaricaceae)4属27种植物的花粉形态。中国柽柳科植物花粉为三沟类型,无三拟孔沟类型,形态及外壁雕纹属间差异明显。根据花粉资料,探讨了属间的进化关系和分类地位及本科植物花粉外壁的演化途径。  相似文献   
2.
Shoot cultures of Tamarix tetrandra on Linsmaier–Skoog (LS) agar medium with 30 g l−1 sucrose, 2.13 mg l−1 indoleacetic acid and 2.25 mg l−1 benzyl adenine produced ellagitannins found in intact plants of the Tamaricaceae. This was demonstrated by the isolation of 14 monomeric–tetrameric ellagitannins from the aq. Me2CO extract of the cultured tissues. This is the first report on the production of ellagitannin tetramers by plant tissue culture. The effects of light and certain medium constituents on tissue growth and ellagitannin production were examined. The contents of representative tannins of different types [i.e., tellimagrandin II (monomer), hirtellin A (linear GOG-type dimer), hirtellin B (hellinoyl-type dimer), hirtellin C (macrocyclic-type dimer), and hirtellin T1 (linear GOG-type trimer)] in the resultant tissues in response to these factors were estimated by HPLC, and the optimal condition for production of these tannins were established. Shoots cultured on LS hormone-free medium promoted root development, and regenerated plants could adapt to ordinary soil and climate. Acclimatized and intact T. tetrandra plants that were collected in November and May, respectively, demonstrated seasonal differences in individual ellagitannin contents. HPLC comparison of individual ellagitannin contents in different plant materials (i.e., leaves, stems, and roots) of intact T. tetrandra plants is also reported. The results are discussed with respect to cellular deposition and biosynthetic relationship of tannins.  相似文献   
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4.
The debarked roots of Tamarix nilotica contain the furanofuran lignan (±)-syringaresinol so far not reported from the Tamaricaceae, and the new natural product ellagic acid 3,3′-dimethyl ether 4-O-β-d-glucopyranoside. Further constituents were isoferulic acid, gallic acid, dehydrodigallic acid and ellagic acid. The structure of the isolated compounds was determined mostly by 1H and 13C NMR spectroscopy.  相似文献   
5.
We have discovered that leaves from the halotolerant plant saltcedar (Tamarix canariensis [Willd.]) are a source of resorcinols and guaiacols. Specifically, the waxes of the saltcedar leaves contained high amounts of 5-n-alkylresorcinols (ARs; 17 g/kg dry weight), 5-n-alkyl-m-guaiacols (AGs; 14 g/kg dw) and secondary alcohols (44 g/kg dw). Herein we provide the report of 5-n-alkylresorcinols with long side-alkyl chains as natural compounds in Tamaricaceae. These compounds are homologous to ones previously reported almost exclusively in cereals. The ARs span the formulas n-C14 to n-C27, the most abundant of which is n-C21. Although the odd-C-numbered compounds dominate, there are non-negligible amounts of the even-numbered homologs. We also provide, the first-ever report of 11 homologs of 5-n-alkyl-m-guaiacols (AGs) as natural compounds from the sample plant, which we characterized as the corresponding trimethylsilyl (TMS)-ether derivatives. The AGs contain a hydroxyl group at carbon 1 of the phenolic nucleus, a methoxy group at position 3, and a (predominantly odd-C-numbered) linear alkyl chain linked to the benzene ring at position 5. They span the formulas n-C13 to n-C27, the most abundant of which is n-C21. Finally, we also isolated from saltcedar a series of eight asymmetric secondary alcohols, whose formulas range from n-C25 to n-C35 and whose major homolog is n-hentriacontan-12-ol.  相似文献   
6.
柽柳科(Tamaricaceae)植物的研究历史   总被引:12,自引:0,他引:12  
柽柳科(Tamaricaceae)是一个古老的科,起源于第三纪,包括亚洲中部的内的“古地中海”沿岸地区,该科植物主要为旱生植物,其中大多数种是防风、固沙造林和水土保持的优良树种,对改造沙漠和改善气候条件具有重要的生态意义。同时,该科植物在荒漠地区还具有广泛的经济用途。  相似文献   
7.
中国水柏枝属植物的地理分布、濒危状况及其保育策略   总被引:2,自引:0,他引:2  
水柏枝属(MyricariaDesv.)植物主要分布于中国青藏高原及其邻近地区,为欧亚温带高山植物类群,多为河岸带植物,是分布区湿地生态系统和荒漠生态系统的重要组分。为评价这些特殊生态系统关键植物的分布及受威胁现状,对中国水柏枝属植物的地理分布和濒危状况进行了调查。调查发现,该属中国分布的11个分类群均受到生存胁迫,其中疏花水柏枝即将成为野外灭绝种,宽叶水柏枝已属极危种,心叶水柏枝为濒危种,秀丽水柏枝、泽当水柏枝、小花水柏枝、卧生水柏枝和匍匐水柏枝为渐危种,具鳞水柏枝、三春水柏枝和宽苞水柏枝为受胁种。结果表明,以水利建设为主的人为干扰和土地沙化、气温升高带来的环境改变是导致该属植物生存胁迫的主要原因。最后探讨了水柏枝属这类河岸带湿地和荒漠生境植物的保育策略。  相似文献   
8.
An ellagitannin monomer, nilotinin M1 (1), and three dimers, nilotinins D1 (2), D2 (3), and D3 (4), were isolated from leaves of Tamarix nilotica (Ehrenb.) Bunge. Structures were elucidated based on analysis of spectroscopic data and chemical correlations with known compounds. In addition, six known tannins, hirtellin A (5) (dimer), remurin A (6), remurin B (7), 1,3-di-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-β-d-glucose (8), gemin D (9), and hippomanin A (10) (monomers), were isolated for the first time from this plant species. The reported 13C NMR assignments of the dehydrodigalloyl moiety and glucose cores of 5 are revised, and the 13C NMR spectroscopic data for 6 and 7 are also reported for the first time.  相似文献   
9.
中国柽柳科植物叶解剖特征与分类关系的探讨   总被引:23,自引:5,他引:18  
对分布于新疆的柽柳科植物叶的结构进行了比较观察,结果表明:水柏枝属叶为一般背腹叶,具湿中性特征;红砂属植物的叶横切面呈扁圆形,栅栏组织呈现状排列于表皮之下;柽柳属的叶与一般的背腹叶不同,栅栏组织位于远轴面,海绵组织位于近轴面。同时对叶的解剖结构与分类关系进行探讨,认为柽柳科植物的某些叶特征稳定且具类群特异性,在确定亲缘关系和分类方面具有重要意义。最后列出了柽柳科分属和柽柳属分种检索表。  相似文献   
10.
中国干旱区柽柳科植物种子形态特征及其系统学意义   总被引:9,自引:0,他引:9  
对中国干旱区柽柳科(Tamaricaceae)植物3属7代表种的种子形态及种皮表面亚显微结构进行了观察,表明种子形态及种皮表面亚显微结构可为本科植物的分类提供有价值的信息。根据种子表皮毛着生的类型并结合外部形态特征可初步得出以下结论:(1)表皮毛可分为Ⅰ型表皮毛和Ⅱ型表皮毛,前者着生于种子表面,包括红砂属(ReaumuriaL.)和柽柳属(TamarixL.)植物的一些种类;后者着生于种子顶端的芒柱上,包括柽柳属一些种类和水柏枝属(MyricariaDesv.)植物。(2)表皮毛的演化趋势是由Ⅰ型表皮毛向Ⅱ型表皮毛转化。(3)红砂属处于本科的原始地位,水柏枝属较为进化,柽柳属是联系两者的中间环节,本属内亦存在许多过渡类型。  相似文献   
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