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51.
Petrocosmea glabrstoma ZJ. Qiu & YZ. Wang, a new species from Yunnan Province, China, is described and illustrated. The new species is similar to Petrocosmea forrestii Craib and Pmairei Lévl., but differs from them mainly by its leaves triangular or triangular ovate, corolla glabrous inside with shorter filament. Molecular and morphological data demonstrate that this new species has a close affinity to Pforrestii.  相似文献   
52.
杜仲药用有效成分提取方法研究   总被引:16,自引:0,他引:16  
为优选杜仲的提取工艺条件 ,本实验以杜仲提取液中氯原酸的含量和浸膏得率为指标 ,采用四因素三水平正交设计法 ,筛选影响杜仲提取工艺的因素 ,探索最优的提取工艺条件。实验证明合理的提取方法为 :12倍 6 0 %的乙醇回流 3次 ,每次 2小时 ;所得杜仲提取物中氯原酸含量为 8 72mg/g生药 ,浸膏得率为 2 0 6 8%。  相似文献   
53.
大血藤不同器官黄酮类化合物含量的季节变化   总被引:7,自引:0,他引:7  
大血藤〔Sargentodoxacuneata (Oliv .)Rehd .etWils.〕隶属木通科 (Lardizabalaceae)大血藤属 (SargentodoxaRehd .etWils.) ,为落叶木质藤本 ,根和藤可入药 ,有强筋骨、活血散瘀、止痛、通经之效 ,并可治疗阑尾炎、风湿性关节炎等 ,又可用作杀虫剂[1] 。大血藤是中国特有中药材 ,入药部位为一年生嫩茎 ,但在中医临床应用上并不广泛。有关大血藤次生代谢产物的研究较少。Romker等从大血藤分离出三萜类皂素如儿茶素等 ,并发现在体内具有明显的抗病毒效应[2 ] …  相似文献   
54.
杜仲含胶细胞形态特征的研究   总被引:5,自引:0,他引:5  
利用离析、石蜡制片以及电镜扫描等方法对杜仲含胶细胞的形态特征进行研究,结果表明,大多数的含胶细胞是一种细长的、两端略膨大的,丝状的分泌单细胞、少数含胶细胞在表面形成突起,并能进一步伸长,形有盲端或分枝。  相似文献   
55.
用扫描电镜观察桂南木莲(Manglietia chingii Dandy)和木莲(Manglietia fordiana Oliv.)两种木莲属植物的花器官发生及发育过程。结果显示,两种植物的花被片皆为向心发生,木莲的花被片3基数3轮,而桂南木莲的花被片4轮,前3轮3基数,第4轮普遍存在退化现象。雄蕊与心皮皆多枚,螺旋状向心发生。两种植物花发育的特殊之处在于花被片为轮状不同时发生,即从发生位置上看为3基数轮生,但同一轮花被片之间在发生时间上存在差异。这种花被片的轮状不同时发生可能是螺旋状发生向轮状发生演化的一个过渡阶段,这对探讨被子植物花器官发生与发育的演化具有重要意义。  相似文献   
56.
The double fertilization and embryo development of P. lasiocarpa were studied using cytochemical method for DNA, RNA, polysaccharides and proteins. Stigmas were covered by secretion stained positively with PAS and mercuric bromphenol blue at receptive stage. The pollen grains germinated on the stigma in large quantities 6 hours after pollination. Fertilization started at the 6th days after pollination. The sperm nucleus fused with the secondary nucleus faster than the sperm nucleus with the egg nucleus. The syngamy belonged to peremitotic type. A great deal of starch grains in the embryo sac disappeared during fertilization. The endosperm was nuclear type and becomed a cel 31 days after pollination. The endosperm was characterized by a dense cytoplasm rich in protein. No discrete starch grains were observed in endosperm. Afterwards, the endosperm was consumed by the developing embryo, thus the mature seeds were non-endospermous. The zygote was dormant for 6–8 days. During the dormency, many striking changes took place, and then, the zygotes showed more pronounced polarity. These changes included the shinkage of the large vacuole, the reduced size, the reappearance of large vacuole, the enlarging of the size. The embryogenesis conformed to the Solanad type. The ovules matured into seeds successively 44 days after pollination. The mature embryo was straight. Two cotyledons folded each other.  相似文献   
57.
不同地理种源杜仲叶片中绿原酸和总黄酮的含量   总被引:8,自引:1,他引:7  
杜仲(EucommiaulmoidesOliv.)是我国所特有的经济植物。传统以树皮入药,近年来研究表明,杜仲叶与皮的化学成分基本相同,药效类似[1~4]。杜仲叶、皮中主含环烯醚萜甙类、黄酮类及酚酸类成分。研究不同地理种源和不同季节杜仲叶片绿原酸和总...  相似文献   
58.
Seven constituents have been isolated from the bark of Eucommia ulmoides Oliv. Based on spectral analysis and determination of Physico-chemical constants they have been identified as: nonacosane (Ⅰ), n-triacontanol (Ⅱ), β-sitosterol (Ⅲ), betulin (Ⅳ), betulic acid (Ⅴ), ursolic acid (Ⅵ), vanillic acid (Ⅶ).  相似文献   
59.
杜仲胚发育过程的研究   总被引:1,自引:0,他引:1  
西安地区栽培杜仲,4月中旬传粉,下旬受精。合子休眠35天左右。6月初形成原胚,6—8月胚分化发育,10月种子成熟。合子在休眠期,其体积增长1—1.5倍,极性渐显著。合子经两次横分裂,形成线形排列的四细胞原胚。其后基细胞衍生的细胞参与胚体的形成,胚的发育属藜型。胚柄单列细胞,靠珠孔端一个形大,具吸器作用。胚的后期发育与一般双子叶植物相同。  相似文献   
60.
Acanthopanax (A.) henryi (Oliv.) Harms contain many bioactive compounds commonly used in traditional Chinese medicine. The objective of the present study was to investigate the antibacterial activity of the single constituent, Eleutheroside K (ETSK) isolated from the leaves of A. henryi (Oliv.) Harms, against methicillin-resistant Staphylococcus (S.) aureus (MRSA). Broth microdilution assay was used to measure the minimal inhibitory concentration (MIC) and the MIC values of ETSK against eight clinical S. aureus strains were all 50 µg ml−1. At sub-inhibitory concentrations, a synergistic effect between oxacillin (OXA) and ETSK was confirmed using checkerboard dilution assay and time-kill curve analysis. The bacteriostatic effect became more pronounced when ETSK was used in combination with detergent (Triton X-100) or ATPase inhibitor (N, N′-dicyclohexylcarbodiimide). According to western blot analysis, the down-regulated expression of Penicillin-binding protein 2a (PBP2a) further validated that the bacterial activity was inhibited when treated with ETSK in a dose-dependent manner. Results based on our study verified that ETSK significantly suppressed MRSA infections and emphasized the potential application of ETSK as a novel anti-MRSA natural drug.  相似文献   
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