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91.
Salvia miltiorrhiza Bunge is a natural drug for treating myocardial infarction (MI). However, the targets and mechanisms of S. miltiorrhiza Bunge in the treatment of MI are yet to be elucidated. Traditional Chinese medicine systems pharmacology (TCMSP) data were used to screen out chemical constituents, and UniProt was used to predict relevant targets. Disease targets were obtained from the Online Mendelian Inheritance in Man and GeneCards databases. We used the STRING platform to build a protein–protein interaction network and used Cytoscape_v3.8.1 software to make a Drug–Ingredients–Gene Symbols–Disease network map. The Metascape database was used to perform gene ontology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses for drug–disease overlapping gene symbols. The targets identified by network pharmacology were further verified by in vitro and in vivo experiments. Seventy-five active components of S. miltiorrhiza Bunge were obtained from the TCMSP database, while 370 disease targets and 29 cross-targets were obtained from the Genecards database. The KEGG pathway enrichment results suggested that the mechanism of S. miltiorrhiza Bunge in the treatment of MI was significantly related to the VEGF signalling pathway. In vitro and in vivo experiments were used to evaluate the reliability of some important active ingredients and targets. S. miltiorrhiza Bunge alleviated the damage to cardiac function, attenuated myocardial fibrosis and protected endothelial cell function by increasing the expression of TGF-β and VEGFA. S. miltiorrhiza Bunge showed the therapeutic effect of MI by promoting the expression of VEGFA signalling pathway, providing a reliable basis for exploring herbal treatment of MI.  相似文献   
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A high-frequency and simple procedure for Agrobacterium tumefaciens-mediated genetic transformation of the medicinal plant Salvia miltiorrhiza was developed. Leaf discs were pre-cultured on MS medium supplemented with 6.6 μmol l−1 BAP and 0.5 μmol l−1 NAA for one day, then co-cultured with A. tumefaciens strain EHA105 harboring the plasmid pCAMBIA 2301 for three days on the same medium. Regenerated buds were obtained on selection medium (co-culture medium supplemented with 60 mg l−1 kanamycin and 200 mg l−1 cefotaxime) after two cycles’ culture of 10 days each and then transferred to fresh MS medium with 60 mg l−1 kanamycin for rooting. Fifteen days later, the rooted plantlets were obtained and then successfully transplanted to soil. The transgenic nature of the regenerated plants was confirmed by PCR, Southern hybridization analysis and GUS histochemical assay. Averagely, 1.1 independent verified transgenics per explant plated were obtained through this protocol. Adopting this procedure, positive transformed plants could be obtained within 2–3 months from mature seeds germination to transplant to soil, and more than 1,000 transgenic plants with several engineered constructs encoding different genes of interest were produced in our lab in the past two years.  相似文献   
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丹参愈伤组织的诱导及增殖效应   总被引:4,自引:0,他引:4  
以丹参(Salvia miltiorrhiza bunge)的幼叶、茎、叶柄为外植体,接种于附加2,4—D、MM、Kr、Zr、6—BA及其组合的hIs固体培养基上,结果发现单独使用四种植物生长调节物质在一定浓度范围均有愈伤组织产生;最佳组合的诱导培养基为MS 2,4—D0.5mg/L 6—BA1.0mg/L。进一步研究发现,在黑暗和光照培养条件下,愈伤组织增殖呈“S”型,且生长周期均为30天。  相似文献   
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BACKGROUND AND AIMS: Salvia divinorum produces several closely related neoclerodane diterpenes. The most abundant of these, salvinorin A, is responsible for the psychoactive properties of the plant. To determine where these compounds occur in the plant, various organs, tissues and glandular secretions were chemically analysed. A microscopic survey of the S. divinorum plant was performed to examine the various types of trichomes present and to determine their distribution. METHODS: Chemical analyses were performed using thin layer chromatographic and histochemical techniques. Trichomes were examined using conventional light microscopy and scanning electron microscopy. KEY RESULTS: It was found that neoclerodane diterpenes are secreted as components of a resin that accumulates in peltate glandular trichomes, specifically in the subcuticular space that exists between the trichome head cells and the cuticle that encloses them. Four main types of trichomes were observed: peltate glandular trichomes, short-stalked capitate glandular trichomes, long-stalked capitate glandular trichomes and non-glandular trichomes. Their morphology and distribution is described. Peltate glandular trichomes were only found on the abaxial surfaces of the leaves, stems, rachises, bracts, pedicles and calyces. This was consistent with chemical analyses, which showed the presence of neoclerodane diterpenes in these organs, but not in parts of the plant where peltate glandular trichomes are absent. CONCLUSIONS: Salvinorin A and related compounds are secreted as components of a complex resin that accumulates in the subcuticular space of peltate glandular trichomes.  相似文献   
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王发松  温铁龙  牛苗  李琳 《广西植物》2015,35(2):178-186
鼠尾草属是唇形科中最大的属,全球有近1 000种。我国是鼠尾草属东亚分布中心,有84种,分布于全国各地,尤以西南地区最多。鼠尾草属植物具有很高的经济价值和观赏价值,但由于鼠尾草属植物分布广、种类多、形态变异大,给该属鉴定和分类学研究带来了很大的困难。此外,在采集和调查过程中发现弧隔鼠尾草亚属和荔枝草亚属的很多种类在营养生长期仅通过叶片很难鉴定。表皮毛是植物叶片上最常见的附属物,其分布特性和形态特征常作为植物鉴定和分类学研究的重要手段。该文利用光学显微镜和环境扫描电镜对18种和1变型共19份鼠尾草属植物的叶片类型、表皮细胞形状、垂周壁样式、气孔器类型和表皮毛等叶表皮微形态特征进行了观察和比较研究,为鼠尾草属的分类界定研究提供证据。结果表明:这19份鼠尾草属植物叶表皮和表皮毛形态特征在电子显微镜下表现出明显的多样性,叶表皮细胞形状为不规则形或多边形,垂周壁多数为浅波状或波状,少数为平直或弓形。气孔器为无规则型和不等细胞型,其中无规则型最为常见。样品叶表皮毛分为4个类型,盾状腺毛、头状腺毛、短非腺毛和长非腺毛。该属植物叶表皮的这些微形态特征,可为本属鉴定和分类学研究提供理论依据。  相似文献   
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A new neo-clerodane diterpenoid, salvihispin H ( 1 ), and six known ones ( 2 – 7 ) were identified from the aerial parts of Salvia hispanica L. The structure and absolute configuration of 1 were elucidated by extensive analysis of spectroscopic (1H, 13C, and 2D NMR, and HR-ESI-MS) and single-crystal X-ray diffraction data. The anti-diabetic effects of salvihispin H ( 1 ) and salvifaricin ( 2 ) were evaluated in diabetic db/db mice. The data showed that 1 and 2 could significantly reduce fasting blood glucose level and improve insulin resistance, and compound 1 exerted glucose-lowering effect more quickly than metformin. In addition, 1 and 2 could also reduce serum TG level in db/db mice. These results demonstrated that compounds 1 and 2 could be considered as potent candidates for the therapy of type 2 diabetes mellitus (T2DM).  相似文献   
100.
一种由蜂类和鸟类传粉的鼠尾草属植物的花生物学:建立了有性阶段、花蜜动态过程和 繁育系统与访花行为的联系 在对传粉综合征的认知过程中,人们已经意识到共享某类传粉媒介的植物间的花表型中存在着适应性趋同的现象。然而,虽然许多植物都表现出了与特定综合征相关的性状,但它们的访花传粉者却不止一种。这种情况可能意味着传粉媒介的变化,或者可能形成了一种可适应不同传粉媒介的稳定情况。此前在鼠尾草属Salvia  stachydifolia 中开展的一项研究表明,该物种的花形状可以最大限度地提升蜜蜂和蜂鸟的传粉效果。在本文中,我们研究了该物种的花生物学的另外3个方面:有性阶段、花蜜动态过程和繁育系统,并探讨了它们与传粉者行为之间的联系,以了解该物种在这3个方面上对蜜蜂和/或蜂鸟传粉的适应性变化。我们以某一温室种群为研究对象,对其在5种不同传粉方式下的繁育系统进行了刻画。为了确定有性阶段,我们分别对花开、花药开裂、花冠掉落和柱头可授性的情况进行了记录。此外,我们还对花蜜体积和浓度在一整天的动态变化进行了表征。最后,为了确定传粉者的 组成和访花模式,我们开展了实地观测并记录传粉者的行为。研究结果显示,S. stachydifolia 是部分雄蕊 先成熟且可自交,但自由授粉植株的繁殖成功率最高,表明繁殖过程主要取决于传粉者的活动。熊蜂属Bombus opifex (一种大黄蜂)是最常见的访花者,但在清晨和黄昏时占主导地位的访花者则是红尾慧星蜂鸟(Sappho sparganura)。花蜜常见于大黄蜂授粉的情况。我们认为蜜蜂-蜂鸟混合访花的模式构成了一种不稳定的进化情形,使得S.  stachydifolia 成为一种理想的研究对象,用以了解传粉媒介发生变化的生态环境。  相似文献   
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