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101.
采用各种色谱对硬毛地笋(Lycopus lucidus Turcz.var.hirtus Regel)的化学成分进行分离,通过理化性质和波谱分析进行结构鉴定。从硬毛地笋全草甲醇提取物中分离鉴定了9个化合物:β-胡萝卜素(1),7,3’,4’-三羟基黄酮(2),β-谷甾醇(3),3’,4’,5-三羟基-3,7-二甲氧基黄酮(4),α-香树脂醇(5),β-香树脂醇(6),24-羟基-乌苏-12-烯-28-酸(7),β-胡萝卜苷(8),24-甲基-5α-胆甾-7,22-二烯-6α-醇-3β-O-葡萄糖苷(9)。化合物4,7和9为首次从该科植物中分离得到,化合物1~9均为首次从硬毛地笋中分离得到。  相似文献   
102.
ABSTRACT

Phenolic compounds isolated from pepper (Capsicum annum) have been demonstrated to have neuroprotective effects, whereas the physiological properties of Capsicum annuum var. abbreviatum (CAA) have not been studied. Thus, we investigate the chemical composition and neuroprotective activity of CAA extract (CAAE) in HT22 hippocampus cells against H2O2-induced neurotoxicity. CAAE treatment resulted in a significant protection of H2O2-exposed HT22, this protection ultimately occurred through an inhibition of MDA and ROS levels and an induction of SOD activity. Furthermore, CAAE treatment reduced H202-induced apoptosis though decreasing the expression of pro-apoptotic factors (Bax, cytochrome c, and cleaved caspases-3) while increasing the expression of the anti-apoptotic factors (Bcl-2), as well as the accumulation of nucleus-Nrf2-mediated HO-1 signaling. Interestingly, CAAE has a high concentration of unique phenolic compositions (chlrogenic acid, tangeretin, etc.) than other capsicum annum extracts. Altogether, these findings suggest that CAAE can be a useful natural resource for alleviating neurodegenerative diseases.  相似文献   
103.
Summary

A morphologically distinct variety of Athyrium distentifolium called A. distentifolium var. flexile has been found only in Scotland. Research was undertaken for aUK Biodiversity Action Plan. To confirm that this taxon has a definitely recognisable morphology, a morphometric analysis was used on the range of characters used to define this variety. It showed that it can be clearly differentiated.  相似文献   
104.
Pepino (Solanum muricatum var. pepino) plants were found affected by an extensive leaf spot caused by plant pathogenic fungi during a survey in the Cameron highlands, Pahang state, Malaysia. Symptomatic leaf samples were collected from infected pepino plants and cultivated on PDA medium, and the pathogen was isolated and purified; then, consequently, all isolates were identified as Stemphylium lycopersici on the basis of their cultural and morphological characteristics and combined sequences of the internal transcribed spacer (ITS) and glyceraldehyde‐3‐phosphate dehydrogenase (gpd) regions. A pathogenicity assay on detached leaves further confirmed that S. lycopersici causes leaf spot disease. To the best of our knowledge, this is the first report of S. lycopersici causing leaf spot on pepino in Malaysia and worldwide.  相似文献   
105.
徐长林 《广西植物》2016,36(9):1023-1025
该文描述了甘肃东祁连山发现的豆科( Leguminosae)扁蓿豆属( Melilotoides)一新变种———天祝扁蓿豆(Melilotoides ruthenica var. tianhzhuensis C. L. Xu )。该变种植株节间(3~18 mm)短于原变种(30~65 mm);叶片小于原变种;小叶宽卵形或倒卵形;花冠外部(背部)和内部(腹部)均为黄色,且不带紫色和条纹。上述特征与原变种明显不同,易于区别。  相似文献   
106.
野生小花草玉梅(Anemone rivularis var.flore-minore)正常植株和花被片自然变异植株的外观形态差异很大,该研究以二者为材料,利用常规PCR和高效热不对称PCR(Hi-Tail PCR)技术从其正常和变异植株的基因组中各分离得到1个B类基因。序列分析证明,二者隶属于B类MADS-box基因AP3家族的旁系同源基因AP3-3分枝,分别命名为NArAP3-3(正常植株)和VArAP3-3(变异植株)。NArAP3-3基因全长3 795bp,VArAP3-3基因全长3 898bp,二者均含有1个666bp的开放阅读框(ORF),可编码221个氨基酸,具有典型的植物MADS-box基因结构,其编码肽链包含了MADS区、K区、Ⅰ区和C区。对比NArAP3-3和VArAP3-3基因的全长序列,发现VArAP3-3基因比NArAP3-3多了1段49bp的插入,且在ORF序列与NArAP3-3基因相比有4个碱基突变。对二者的全长序列、所编码的221个氨基酸及插入序列的生物信息学分析显示,二者在基因启动子、蛋白质基本性质、结构功能域、二级三级预测结构等方面均有差异,推测这些差异可能是花被片变异产生的原因之一。该研究结果为进一步探索其变异机制奠定了基础。  相似文献   
107.
This study aims to explore the mechanism of Circular RNA CDR1as implicating in regulating 5‐fluorouracil (5‐FU) chemosensitivity in breast cancer (BC) by competitively inhibiting miR‐7 to regulate CCNE1. Expressions of CDR1as and miR‐7 in 5‐FU‐resistant BC cells were determined by RT‐PCR. CCK‐8, colony formation assay and flow cytometry were applied to measure half maximal inhibitory concentration (IC50), 5‐Fu chemosensitivity and cell apoptosis. Western blot was used to detect the expressions of apoptosis‐related factors. CDR1as was elevated while miR‐7 was inhibited in 5‐FU‐resistant BC cells. Cells transfected with si‐CDR1as or miR‐7 mimic had decreased IC50 and colony formation rate, increased expressions of Bax/Bcl2 and cleaved‐Caspase‐3/Caspase‐3, indicating inhibition of CDR1as and overexpression of miR‐7 enhances the chemosensitity of 5‐FU‐resistant BC cells. Targetscan software indicates a binding site of CDR1as and miR‐7 and that CCNE1 is a target gene of miR‐7. miR‐7 can gather CDR1as in BC cells and can inhibit CCNE1. In comparison to si‐CDR1as group, CCNE1 was increased and chemosensitivity to 5‐Fu was suppressed in si‐CDR1as + miR‐7 inhibitor group. When compared with miR‐7 mimic group, CDR1as + miR‐7 mimic group had increased CCNE1 and decreased chemosensitivity to 5‐Fu. Nude mouse model of BC demonstrated that the growth of xenotransplanted tumour in si‐CDR1as + miR‐7 inhibitor group was faster than that in si‐CDR1as group. The tumour growth in CDR1as + miR‐7 mimic group was faster than that in miR‐7 mimic group. CDR1as may regulate chemosensitivity of 5‐FU‐resistant BC cells by inhibiting miR‐7 to regulate CCNE1.  相似文献   
108.
实时荧光定量PCR技术是探索植物基因功能和调节机理的有效手段。选择合适的内参基因是获得实时荧光定量PCR准确性数据的必备条件。ACT基因高度保守且表达稳定,常作为内参基因被广泛应用。为了获得花椰菜ACT基因,以转录组测序和RT-PCR方法为手段克隆得到花椰菜肌动蛋白基因Actin。该基因等电点为5.395,理论分子量为41.77 kD;其cDNA开放阅读框长1134 bp,编码氨基酸377个,GenBank登录号为MG598643。Wolf Psort分析发现,BobActin蛋白亚细胞定位于细胞质基质中。Motif Scan分析显示,BobActin蛋白质的氨基酸序列4~377位为Actin保守结构域。进化分析表明,同源序列基因编码的蛋白质与同为十字花科的甘蓝、芜菁和油菜同源蛋白的相似性达到90%以上,具有高度的保守性。在此基础上,设计了1对荧光定量PCR引物,分析显示,该引物具有较高的特异性和扩增效率,在花椰菜根、茎、花、花球、叶片等不同组织和低温、高温、盐处理、干旱处理、ABA处理等胁迫处理下均能稳定表达,适合在花椰菜基因表达研究中作为内参基因,为开展花椰菜重要功能基因的挖掘、表达模式以及调控机理的研究提供参考。花椰菜在内参基因方面的研究还处于初步阶段,今后可继续克隆其他内参基因,丰富花椰菜的内参基因库,从而进一步提高花椰菜基因表达分析研究的稳定性、重复性和准确性。  相似文献   
109.
The Upper Rhine Valley, a “hotspot of biodiversity” in Germany, has been treated with the biocide Bacillus thuringiensis var. israelensis (Bti) for mosquito control for decades. Previous studies discovered Bti nontarget effects in terms of severe chironomid abundance reductions. In this study, we investigated the impact of Bti on species level and addressed the community composition of the nontarget family Chironomidae by use of community metabarcoding. Chironomid emergence data were collected in three mosquito‐control relevant wetland types in the Upper Rhine Valley. For all three sites the chironomid species composition, based on operational taxonomic units (OTUs), was different to varying degrees in the Bti‐treated samples versus control samples, ranging from a significant 63% OTU reduction to an OTU replacement. We assumed that predatory chironomids are less prone to Bti than filter feeders, as the latter feed on floating particles leading to direct ingestion of Bti. However, a comparable percentage of predators and filter feeders (63% and 65%, respectively) was reduced in the Bti samples, suggesting that the feeding strategy is not the main driver for Bti sensitivity in chironomids. Finally, our data was compared to a three‐year‐old data set, indicating possible chironomid community recovery due to species recolonization a few years after the last Bti application. Considering the currently discussed worldwide insect decline we recommend a rethinking of the usage of the biocide Bti, and to prevent its ongoing application especially in nature protection reserves to enhance ecological resilience and to prevent boosting the current biodiversity loss.  相似文献   
110.
尾尖奇蒿(Artemisia anomala var.acuminatissima)(菊科-春黄菊族)1992年发表时未指定模式,故为不合格发表。该名称2011年得以合格发表,故2016年的再次合格发表纯属多余,是有关作者没有仔细查阅文献的结果。该名称的正确引证应为“Artemisia anomala var.acuminatissima Y.R.Ling,Bangladesh J.Plant Taxon.18:203.2011”,而非“Artemisia anomala var.acuminatissima Y.R.Ling,Phytotaxa 273:213.2016”。  相似文献   
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