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Anti-inflammatory germacrane-type sesquiterpene lactones from Vernonia sylvatica
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作者 WANG Min LI Han +6 位作者 HU Bintao TANG Chunping XU Hui KE Changqiang XIE Zuoquan YE Yang YAO Sheng 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第6期568-576,共9页
Nine new germacranolides,sylvaticalides A−H(1-9),and three known analogues(10-12)were isolated from the aeri-al part of Vernonia sylvatica.Their structures were established using comprehensive spectroscopic analysis,i... Nine new germacranolides,sylvaticalides A−H(1-9),and three known analogues(10-12)were isolated from the aeri-al part of Vernonia sylvatica.Their structures were established using comprehensive spectroscopic analysis,including high-resolution electrospray ionization mass spectroscopy(HR-ESI-MS)and 1D and 2D nuclear magnetic resonance(NMR)spectra.Their absolute configurations were determined by X-ray diffraction experiments.The anti-inflammatory activities of all isolated compounds were as-sessed by evaluating their inhibitory effects on the nuclear factor kappa B(NF-κB)pathway,which was activated by lipopolysacchar-ide(LPS)-stimulated human THP1-Dual cells,and the interferon-stimulated gene(ISG)pathway,activated by STING agonist MSA-2 in the same cell model.Compounds 1,2 and 6 showed inhibitory effects on the NF-κB and ISG signaling pathways,with IC_(50)values ranging from 4.12 to 10.57μmol·L^(−1). 展开更多
关键词 Vernonia sylvatica Germacrane-type sesquiterpene lactone sylvaticalides A−H ANTI-INFLAMMATORY NF-κB path-way ISG pathway
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欧洲水青冈(Fagus sylvatical L.)构筑型与形态多样性研究 被引量:43
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作者 李俊清 臧润国 蒋有绪 《生态学报》 CAS CSCD 北大核心 2001年第1期151-155,共5页
通过对植物构件和构筑型的分析 ,可以了解植物的整体结构与系统演化关系。高等植物构筑型的研究以树木最为深入 ,植物学家对全球的树木进行了构筑模式的分类 ,并确定了 2 3个基本的构筑类型。植物的构筑型和其形态的多样性是密不可分的... 通过对植物构件和构筑型的分析 ,可以了解植物的整体结构与系统演化关系。高等植物构筑型的研究以树木最为深入 ,植物学家对全球的树木进行了构筑模式的分类 ,并确定了 2 3个基本的构筑类型。植物的构筑型和其形态的多样性是密不可分的。构筑类型确定了植物所属的整体形态类型 ,而对每种植物具体的形态多样性分析可以深入了解每种构筑型的数量特征及其形成过程。在概述了树木构筑型研究的基础上 ,系统说明了欧洲水青冈构筑型和形态多样性分析的步骤和分析的意义。水青冈属 ( F agus)为 Troll型构筑模式 ,处于不同生态条件下的同一种的不同种群之间 ,在形态、解剖、生理和遗传多样性方面都存在着差异。树木的形态多样性虽然主要受遗传因素的控制 ,但生态条件对其形态和遗传多样性也有非常显著的影响。在对树木进行构筑型分析时 ,首先要根据构筑要素 (主要是形态与生长特性 )确定它所属的构筑模式类型 ,其次是分析它的形态特征与环境条件的关系 ,进而进一步分析其遗传多样性。 展开更多
关键词 构筑型 形态多样性 欧洲水青冈
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林生风毛菊(Saussurea sylvatica)头状花序权衡机制的海拔差异 被引量:2
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作者 王一峰 祁如林 +2 位作者 杨亚军 杨洋 毛婉嫕 《西北师范大学学报(自然科学版)》 CAS 北大核心 2018年第1期61-66,共6页
以广泛分布于青藏高原相对高海拔区的林生风毛菊为研究对象,通过采样调查法和烘干称量法等实验生态学方法研究不同海拔居群间头状花序大小-数量的权衡关系.结果表明,随着海拔的升高,地上生物量、株高、繁殖和营养器官生物量以及每株头... 以广泛分布于青藏高原相对高海拔区的林生风毛菊为研究对象,通过采样调查法和烘干称量法等实验生态学方法研究不同海拔居群间头状花序大小-数量的权衡关系.结果表明,随着海拔的升高,地上生物量、株高、繁殖和营养器官生物量以及每株头状花序数量均呈减小趋势(P<0.01),而繁殖分配(P=0.023)和每个头状花序质量(P=0.02)均呈增大趋势;随着每个头状花序质量的增加,每株头状花序的总数量呈现不断减小趋势.研究发现,高海拔的环境胁迫导致林生风毛菊个体减小,植株在头状花序大小和数量的资源分配上存在"此消彼长"的权衡,即通过增加单个头状花序质量、减小植物头状花序数量的资源分配策略来保证其种群的繁殖成功率,以补偿在高海拔区的恶劣环境对种群繁衍带来不利影响,反映了高山植物资源分配的可塑性以及自身繁殖适合度的提高. 展开更多
关键词 林生风毛菊 头状花序 繁殖分配 权衡机制 海拔差异
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Antioxidant,anti-inflammatory and antinociceptive potential of Ternstroemia sylvatica Schltdl.&Cham
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作者 Claudia V.Moreno-Quirós Alberto Sánchez-Medina +2 位作者 Maribel Vázquez-Hernández Ana G.Hernández Reyes Rosa V.García-Rodríguez 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第11期1047-1053,共7页
ObjectiveTo evaluate the anti-inflammatory, analgesic, antioxidant and acute toxicity of extracts obtained from a successive extraction with solvents of ascending polarity [hexane, hex; chloroform, CHCl<sub>3<... ObjectiveTo evaluate the anti-inflammatory, analgesic, antioxidant and acute toxicity of extracts obtained from a successive extraction with solvents of ascending polarity [hexane, hex; chloroform, CHCl<sub>3</sub> and ethanol (EtOH)] of Ternstroemia sylvatica Schltdl. & Cham.MethodsThe antioxidant potential was evaluated by 2,2 diphenyl-1-picrylhydrazyl, the ferric reducing/antioxidant power assays and by determining the total phenolic content. The anti-inflammatory and antinociceptive effects were evaluated using the in vivo croton oil-induced ear edema, phorbol 12-myristate 13-acetate induced ear edema, carrageenan-induced paw edema, acetic acid-induced writhing and formalin murine models. The acute toxicity was tested using the Lorke’s method in mice.ResultsThe EtOH extract was the most active for the antioxidant potential tests diphenyl-1-picrylhydrazyl (68.70% inhibition), ferric reducing/antioxidant power [(2 431.30 ± 102.10) mmol Fe<sup>2+</sup> and total polyphenols content (215.80 ± 8.50) meqAG/g]. The anti-inflammatory activity was evaluated by topical application of croton oil (2 mg/ear dose) where the EtOH extract showed the strongest activity compared to the control group (45.13% inhibition), whereas in the phorbol 12-myristate 13-acetate model, at the same dose, the CHCl<sub>3</sub> extract showed the highest inhibition (42.88%). In the carrageenan induced edema model, the EtOH extract showed a stronger inhibition compared to indomethacin (56.34% and 50.70% at doses of 250 and 500 mg/kg of extract, respectively) during the first hour. Similarly, the same extract showed the highest analgesic activity (30.60% inhibition) in the acetic acid contortion assay, and in the formalin test it showed a greater effect with respect to the control group in both phases.ConclusionsOur work confirms the value of Ternstroemia sylvatica as an important anti-inflammatory and analgesic plant, whose mechanism seems to be associated to its antioxidant effects, and supports its uses in the Mexican traditional medicine. 展开更多
关键词 Ternstroemia sylvatica ANTI-INFLAMMATORY ANALGESIC Medicinal plants
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Removing harvest residues from hardwood stands affects tree growth, wood density and stem wood nutrient concentration in European beech (Fagus sylvatica) and oak (Quercus spp.)
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作者 Sanjoy Roy Jean-Michel Leban +5 位作者 Bernhard Zeller Gregory van der Heijden Arnaud Reichard Marie-Christine Gehin Philippe Santenoise Laurent Saint-Andre 《Forest Ecosystems》 SCIE CSCD 2022年第2期147-159,共13页
Background:Higher exportation of harvest residues from forests due to increased demand for woody biomass,has reportedly diminished soil mineral resources and may lead to degraded tree nutrition as well as growth.Howev... Background:Higher exportation of harvest residues from forests due to increased demand for woody biomass,has reportedly diminished soil mineral resources and may lead to degraded tree nutrition as well as growth.However,as nutrients become less available in the soil,the remobilization of nutrients in biomass tissues(plant internal cycling)helps sustain tree nutrition.Our study aims to quantify the impact of Removing Harvest Residues and Litter(RHRL)during five years on tree growth,wood density,and stem wood nutrient concentrations in young beech and oak forest stands.Result:Our study found that,RHRL significantly decreased tree growth ring width by 14%,and wood density by 3%,in beech trees,in near bark rings.RHRL also significantly reduced nutrient concentration in near bark and near pith areas of both studied species.Mg,Na and S were found lower by 44%,76%,and 56%,respectively,in near bark area of beech trees.In near bark area of oak trees,K,Ca,Mg,Na,S,and Fe were lower by 20%,25%,41%,48%,41%,and 16%,respectively.K and Mg concentrations decreased more strongly in near pith area compared to near bark area suggesting internal translocation of these two elements.Conclusion:In beech trees,wood density proved to be an important factor while quantifying the effect of removing harvest residuals on tree growth and biomass.Soil nutrient loss intensified the remobilization of nutrients con-tained in older tree rings(close to the pith)towards newly formed rings(close to bark).In our study,in beech trees,K was found to be the most recycled major nutrient.These results demonstrate the potential of such analysis for providing valuable insight into the effect of RHRL in premature stands on the physiological adaptive strategies of trees and an indication of soil fertility status. 展开更多
关键词 Harvest residues Fagus sylvatica Quercus petraea DENDROECOLOGY Dendrochemistry Radial growth Wood density Tree growth Ring width TRANSLOCATION
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Addressing Biodiversity Conservation Methods with Fagus sylvatica Genetic Indicators
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作者 Giovanni Figliuolo 《Open Journal of Genetics》 2014年第2期166-174,共9页
Species biological history revealed by genetic indicators can provide guidelines for long-term biodiversity conservation in Natura 2000 network. Fagus sylvatica is the keystone species which regulates in the Mediterra... Species biological history revealed by genetic indicators can provide guidelines for long-term biodiversity conservation in Natura 2000 network. Fagus sylvatica is the keystone species which regulates in the Mediterranean Eco-Region ecosystem structure, function and composition. Six hundred fifty nine F. sylvatica individuals have been sampled across 20 sites of European interest in Southern Italy and analyzed at 5 microsatellite loci. For sites marked by both maximum heterozygosity (Ho) and minimum heterozygote deficit (Fis) (IT9210210, ITA070099, IT9210205 and IT9220075) it is suggested to avoid impacts by adopting very conservative measures. Promoting migration processes (pollen flow and seed flow) would be appropriate where it has been monitored low heterozygosity and high genetic disequilibrium. Margin effect due to dryness should be buffered with appropriate belts of thermophilus broad leaved tree species. 展开更多
关键词 Fagus sylvatica GENETIC DIVERSITY INDICATOR Natura 2000
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Assessing the combined effects of forest management and climate change on carbon and water fluxes in European beech forests
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作者 Vincenzo Saponaro Miquel De Cáceres +3 位作者 Daniela Dalmonech Ettore D'Andrea Elia Vang Alessio Collalti 《Forest Ecosystems》 2025年第2期346-359,共14页
The consequences of climate change continue to threaten European forests,particularly for species located at the edges of their latitudinal and altitudinal ranges.While extensively studied in Central Europe,European b... The consequences of climate change continue to threaten European forests,particularly for species located at the edges of their latitudinal and altitudinal ranges.While extensively studied in Central Europe,European beech forests require further investigation to understand how climate change will affect these ecosystems in Mediterranean areas.Proposed silvicultural options increasingly aim at sustainable management to reduce biotic and abiotic stresses and enhance these forest ecosystems'resistance and resilience mechanisms.Process-based models(PBMs)can help us to simulate such phenomena and capture early stress signals while considering the effect of different management approaches.In this study,we focus on estimating sensitivity of two state-of-the-art PBMs forest models by simulating carbon and water fluxes at the stand level to assess productivity changes and feedback resulting from different climatic forcings as well as different management regimes.We applied the 3D-CMCC-FEM and MEDFATE forest models for carbon(C)and water(H_(2)O)fluxes in two sites of the Italian peninsula,Cansiglio in the north and Mongiana in the south,under managed vs.unmanaged scenarios and under current climate and different climatic scenarios(RCP4.5 and RCP8.5).To ensure confidence in the models’results,we preliminary evaluated their performance in simulating C and H_(2)O flux in three additional beech forests of the FLUXNET network along a latitudinal gradient spanning from Denmark to central Italy.The 3D-CMCC-FEM model achieved R^(2)values of 0.83 and 0.86 with RMSEs of 2.53 and 2.05 for C and H_(2)O fluxes,respectively.MEDFATE showed R^(2)values of 0.76 and 0.69 with RMSEs of 2.54 and 3.01.At the Cansiglio site in northern Italy,both models simulated a general increase in C and H_(2)O fluxes under the RCP8.5 climate scenario compared to the current climate.Still,no benefit in managed plots compared to unmanaged ones,as the site does not have water availability limitations,and thus,competition for water is low.At the Mongiana site in southern Italy,both models predict a decrease in C and H_(2)O fluxes and sensitivity to the different climatic forcing compared to the current climate;and an increase in C and H_(2)O fluxes when considering specific management regimes compared to unmanaged scenarios.Conversely,under unmanaged scenarios plots are simulated to experience first signals of mortality prematurely due to water stress(MEDFATE)and carbon starvation(3D-CMCC-FEM)scenarios.In conclusion,while management interventions may be considered a viable solution for the conservation of beech forests under future climate conditions at moister sites like Cansiglio,in drier sites like Mongiana conservation may not lie in management interventions alone. 展开更多
关键词 Climate change sensitivity Fagus sylvatica L. Forest management sensitivity Carbon fluxes Water fluxes Stress mitigation Process-based models
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林蛙卵核糖核酸酶的抗肿瘤作用及对淋巴细胞转化的影响 被引量:8
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作者 赵丹玉 侯长余 +1 位作者 王艳杰 曹阳 《中国生化药物杂志》 CAS CSCD 北大核心 2010年第4期228-230,234,共4页
目的研究林蛙卵核糖核酸酶(RNase)的抗肿瘤活性以及对淋巴细胞转化的影响。方法从林蛙卵中提取RNase,并用酶谱分析进行鉴定;采用MTT比色法检测林蛙卵RNase对鼠S180肿瘤细胞株生长以及对淋巴细胞转化的影响。结果从林蛙卵中提取的RNase... 目的研究林蛙卵核糖核酸酶(RNase)的抗肿瘤活性以及对淋巴细胞转化的影响。方法从林蛙卵中提取RNase,并用酶谱分析进行鉴定;采用MTT比色法检测林蛙卵RNase对鼠S180肿瘤细胞株生长以及对淋巴细胞转化的影响。结果从林蛙卵中提取的RNase由大约100个氨基酸残基组成,相对分子质量10000。林蛙蛙卵RNase对鼠S180肿瘤细胞株生长和淋巴细胞转化具有较强的抑制作用,并随着林蛙卵RNase浓度的增加,对S180肿瘤细胞生长率和淋巴细胞转化率的抑制作用随之增加,呈现剂量依赖性。结论林蛙卵RNase对S180肿瘤细胞的生长率和淋巴细胞转化率具有明显的抑制作用。 展开更多
关键词 林蛙 核糖核酸酶 S180细胞株 淋巴细胞转化
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中国林蛙早期胚胎发育的形态学研究 被引量:9
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作者 刘玉文 刘治国 +1 位作者 艾静远 呼汉卫 《沈阳农业大学学报》 CAS CSCD 1989年第1期49-54,共6页
根据中国林蛙早期胚胎发育的外部形态特征、内部构造和生理特性,将中国林蛙胚胎演发程序分为22个时期,并较详尽,细致地描述了各个时期的特点。
关键词 胚胎 发育 中国 林蛙 森蛙
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壮药扁桃叶的质量标准研究 被引量:3
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作者 韦松基 王小新 +1 位作者 薛亚馨 韦威 《中国实验方剂学杂志》 CAS 北大核心 2013年第22期127-129,共3页
目的:制定扁桃叶药材的质量标准,为该药用植物资源的开发利用提供科学依据.方法:根据2010年版《中国药典》方法,鉴别扁桃叶药材的性状、显微特征;检查水分、总灰分、酸不溶灰分;采用薄层色谱(TLC)法进行定性鉴别;采用高效液相法测... 目的:制定扁桃叶药材的质量标准,为该药用植物资源的开发利用提供科学依据.方法:根据2010年版《中国药典》方法,鉴别扁桃叶药材的性状、显微特征;检查水分、总灰分、酸不溶灰分;采用薄层色谱(TLC)法进行定性鉴别;采用高效液相法测定芒果苷的含量.结果:对扁桃叶药材的性状、显微特征进行了描述;根据10个不同产地扁桃叶测定结果,确定水分不得过12%,总灰分不得过16%,酸不溶灰分不得超过5%.浸出物以稀乙醇为溶剂,热浸法测定,浸出物不得少于23%.TLC斑点清晰,分离度好;芒果苷的进样量在0.4~1.4 μg(r=0.999 9)与峰面积积分值呈良好线性关系,平均回收率为100.45%,RSD l.59(n=10),芒果苷含量不得少于2%.结论:所建标准可用于扁桃叶药材的质量控制. 展开更多
关键词 扁桃叶 质量标准 芒果苷
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超重环境下微波辐射对大鼠肝细胞超微结构的影响及林蛙油营养液的保护作用 被引量:2
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作者 曹慧玲 刘红梅 +5 位作者 李春卉 沈楠 雷钧涛 潘文干 方青 孙路阳 《辐射防护》 CAS CSCD 北大核心 2010年第5期300-304,311,共6页
为了解超重环境下微波辐射对大鼠肝组织超微结构的影响及林蛙油营养液的保护作用,采用离心机模拟6G超重环境,微波照射(微波源统一由大功率微波雷达发射机改装而成的微波发射机所发射,200mW/cm2,照射5min),用以长白山特产林蛙油为主要成... 为了解超重环境下微波辐射对大鼠肝组织超微结构的影响及林蛙油营养液的保护作用,采用离心机模拟6G超重环境,微波照射(微波源统一由大功率微波雷达发射机改装而成的微波发射机所发射,200mW/cm2,照射5min),用以长白山特产林蛙油为主要成分制成的林蛙油营养液于不同时间给予大鼠,分别观察各组(A组为空白对照,B组为林蛙油营养液,C组为超重+辐射,D组为超重+辐射+林蛙油营养液,E组为林蛙油营养液+超重+辐射,F组为林蛙油营养液+超重+辐射+林蛙油营养液)大鼠肝的超微结构变化,检测大鼠血清己糖激酶活性。结果表明,各组大鼠肝脏超微结构的损伤从轻到重的排列是依次为F、B、A、D≌E、C;A、B和F组大鼠血清己糖激酶活性高于C、D和E组(p<0.05),A、B、F组之间,C、D、E组之间无显著差异(p>0.05)。说明林蛙油营养液对在超重和微波辐射环境下的大鼠肝脏有一定的保护作用,林蛙油营养液使用时间越长,作用越明显。 展开更多
关键词 超重 微波辐射 林蛙油营养液 超微结构
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林蛙肉火腿肠的研制 被引量:2
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作者 刘学军 胡耀辉 +2 位作者 谢春阳 吴晓光 于雷 《食品科学》 EI CAS CSCD 北大核心 2005年第6期284-285,共2页
本文以林蛙肉、林蛙骨泥等为原料,主要研究了林蛙肉火腿肠的加工工艺。经正交试验得出林蛙肉火腿肠的最佳配方:林蛙肉:肥肉为80:20,林蛙骨泥用量为15%,淀粉用量为7%,大豆分离蛋白用量为3%。
关键词 林蛙肉 火腿肠
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山毛榉太阳能间歇干燥节能率与应力分析 被引量:4
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作者 沙汀鸥 杨飞 +1 位作者 张璧光 伊松林 《木材加工机械》 北大核心 2014年第6期37-40,共4页
以尺寸规格为220ram×45mm×20ram(长度×宽度×厚度)的山毛榉(Fagussylvatica)为试材,在间歇率为0%、33%、50%、66%的条件下进行太阳能干燥。通过对干燥速率、节能率以及干燥应力的对比分析,就不同间歇程度... 以尺寸规格为220ram×45mm×20ram(长度×宽度×厚度)的山毛榉(Fagussylvatica)为试材,在间歇率为0%、33%、50%、66%的条件下进行太阳能干燥。通过对干燥速率、节能率以及干燥应力的对比分析,就不同间歇程度对太阳能干燥的影响进行了研究,得出具体结论如下:间歇阶段有助于干燥过程的进行,在减少加热时间的同时,能够使干燥速率比理论值提高32%~80%;间歇干燥可以使节能率提高37.4%~56.8%,且间歇率越高节能率也越高;随着间歇率的提高,试件残余应力指数降低24.4%~34.1%;综合间歇干燥速率、节能率和残余应力指数,选择33%间歇率为最优工况。 展开更多
关键词 太阳能干燥 山毛榉 间歇率 能耗 干燥应力
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欧洲山毛榉不同月份光合特性研究 被引量:2
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作者 卢绍辉 袁国军 +2 位作者 龚东风 杨昆 马俊青 《中国野生植物资源》 CSCD 2022年第9期36-43,共8页
目的:研究欧洲山毛榉(Fagus sylvatica L.)在不同月份的光合特性差异,为探究欧洲山毛榉的主要生长时期及园林栽培和应用提供理论基础。方法:采用Li-6400XT型便携式光合测定系统对5年生欧洲山毛榉6、7、8、9月的净光合速率(Pn)、蒸腾速率... 目的:研究欧洲山毛榉(Fagus sylvatica L.)在不同月份的光合特性差异,为探究欧洲山毛榉的主要生长时期及园林栽培和应用提供理论基础。方法:采用Li-6400XT型便携式光合测定系统对5年生欧洲山毛榉6、7、8、9月的净光合速率(Pn)、蒸腾速率(Tr)、胞间CO_(2)浓度(Ci)、气孔导度(Gs)的日变化及光响应曲线进行测定。结果发现欧洲山毛榉不同月份的光合特性:6月份的Pn呈“双峰型”曲线,且Pn值显著高于其他月份;Tr均呈“单峰型”曲线,且6月Tr值显著高于其他月份,各个月份的Ci值日变化趋势基本一致,均是先下降后上升;4个月份Gs日变化趋势比较一致,但6月、7月的Gs值高于8月、9月;欧洲山毛榉在各月份的Pn、Tr、Gs大小顺序表现为6月>7月>8月>9月,而6月的Ci值显著低于9月份,其余月份之间的Ci值无显著差异,说明欧洲山毛榉6月份的生长速度高于其他月份。相关性分析可知,7月份Pn与Gs呈极显著正相关,与Tr呈显著正相关,9月份Pn与Ci呈极显著正相关。欧洲山毛榉光响应曲线测定发现当表观量子效率为0.0241,暗呼吸速率为-0.8824μmol/m^(2)·s,光补偿点为36.614μmol/m^(2)·s,光饱和点为1925μmol/m^(2)·s时,最大净光合速率为7.6613μmol/m^(2)·s。结论:欧洲山毛榉主要生长时期在6至7月份,在此期间,应做好遮阴措施,减少欧洲山毛榉出现“午休”现象,延长欧洲山毛榉生长时间。 展开更多
关键词 欧洲山毛榉 光合特性 光响应曲线
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山毛榉热处理材的介电式含水率仪读数校正实验 被引量:1
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作者 李涛 王佩 +1 位作者 蔡家斌 周定国 《西部林业科学》 CAS 北大核心 2014年第1期104-107,共4页
采用介电式含水率仪对山毛榉常规干燥材及热处理材的含水率进行了测量,并与烘干法测量结果进行了对比分析,采用最小二乘法,分别拟合出了180℃、195℃和210℃山毛榉热处理材的校正曲线。180℃、195℃和210℃山毛榉热处理材的介电式含水... 采用介电式含水率仪对山毛榉常规干燥材及热处理材的含水率进行了测量,并与烘干法测量结果进行了对比分析,采用最小二乘法,分别拟合出了180℃、195℃和210℃山毛榉热处理材的校正曲线。180℃、195℃和210℃山毛榉热处理材的介电式含水率仪校正曲线分别为,y=1.292 3x+0.278 3,y=1.392 0x+0.747 3,y=1.644 5x+1.489 2。结果表明,常规干燥材的电测法结果能很好地反映其实际含水率水平,而热处理材的电测法结果则普遍大于烘干法,3种热处理材均呈现出随含水率的增高,差值随之增大的趋势,且随着处理温度的升高,差值愈大。 展开更多
关键词 山毛榉 热处理 含水率 介电式含水率仪 校正
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林茜草总黄酮对S-180肿瘤免疫干预机制研究 被引量:4
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作者 刘德财 王雪 +3 位作者 李晶 韩月新 于菁妮 张跃华 《黑龙江医药》 CAS 2016年第3期392-395,共4页
本课题应用从林茜草根中纯化提取的林茜草总黄酮,以小鼠肿瘤S^(-1)80为实验主体,研究其对肿瘤细胞诱导凋亡的作用。采用黄酮类物质对小鼠体内肿瘤细胞诱导凋亡实验,证实林茜草黄酮对S^(-1)80癌细胞有较好的抑制作用,并观察其诱导细胞凋... 本课题应用从林茜草根中纯化提取的林茜草总黄酮,以小鼠肿瘤S^(-1)80为实验主体,研究其对肿瘤细胞诱导凋亡的作用。采用黄酮类物质对小鼠体内肿瘤细胞诱导凋亡实验,证实林茜草黄酮对S^(-1)80癌细胞有较好的抑制作用,并观察其诱导细胞凋亡和抗免疫逃避机制,为临床中西联合用药进一步提高肿瘤的治疗效果,探索肿瘤综合治疗提供实验依据。实验表明,TGC的作用机制可能是干预肿瘤细胞表面免疫分子的识别和表达,从而增强对应特异性细胞的免疫应答响应功能,依此途径制约肿瘤细胞在体内转移和定殖。 展开更多
关键词 林茜草 总黄酮 S-180肿瘤 坏死因子TNF-α
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65~70mm厚欧洲山毛榉锯材干燥基准的研究 被引量:2
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作者 艾沐野 柳宏奇 王缘棣 《林业科技》 北大核心 2001年第5期38-41,共4页
对65~70 mm 厚的欧洲山毛榉锯材干燥生产进行了初步试验研究,提出了可供企业参考的木材加工生产用干燥基准。
关键词 欧洲山毛榉 木材干燥 干燥基准 锯材
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Nutrient retention and release in coarse woody debris of three important central European tree species and the use of NIRS to determine deadwood chemical properties 被引量:4
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作者 Steffen Herrmann Jurgen Bauhus 《Forest Ecosystems》 SCIE CSCD 2018年第3期296-310,共15页
Background: Coarse woody debris(CWD) is very important for forest ecosystems, particularly for biodiversity and carbon storage. Its relevance as a possible reservoir and source of nutrients is less clear, especially i... Background: Coarse woody debris(CWD) is very important for forest ecosystems, particularly for biodiversity and carbon storage. Its relevance as a possible reservoir and source of nutrients is less clear, especially in central Europe.Methods: Based on a chronosequence of known ages of logs, we analyzed the nutrients stored in CWD of Fagus sylvatica, Picea abies, and Pinus sylvestris at different sites in Germany. To quantify nutrient concentrations, we assessed the use of Near Infrared Reflectance Spectroscopy(NIRS) to determine the chemical properties of CWD.Results: NIRS models were suitable to predict concentrations of C, N, P, lignin and extractives. Concentrations of most nutrients increased with mass loss, with the exception of potassium, which decreased for beech and pine and remained relatively constant for spruce. The highest nutrient concentrations(N, P, S, Ca and Mn, except Mg and K) were generally observed in highly decomposed spruce logs. The net effect of decreasing CWD mass and increasing nutrient concentrations was either a decreasing(N, P and K in beech; P, Mg, K and Mn in pine), constant(S, Ca and Mg in beech; N, S and Ca in pine) or increasing amount of nutrients(N, P, S and Ca in spruce; Mn in beech) in the logsover the course of decomposition. The C/N ratio decreased for all tree species, most markedly for spruce from ca. 1000 at the beginning of the decomposition process to 180 at 36 years. The N/P ratio converged to a value of about 30 forall three species. Lignin concentrations increased for spruce and beech and remained constant for pine.Conclusions: Our results indicate that most nutrients remain in CWD for long periods. Nutrients may be used and cycled by microorganisms within CWD, but with the exception of P(in beech), Mg(in pine) and K(in beech and pine), there appears to be little net nutrient export until two thirds of the mass is lost. Instead, N, P, S and Ca were accumulated in spruce logs, indicating that CWD became a net sink rather than a net source of some nutrients for several decades. 展开更多
关键词 CWD NIRS Decay Carbon F.sylvatica P.abies P.sylvestris
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微波消解-ICP-OES法测定花草茶勿忘我中的矿质元素 被引量:3
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作者 曹蕾 乔胜军 魏永生 《化学工程师》 CAS 2015年第10期18-20,共3页
采用浓HNO3-H2O2混合酸体系,以微波消解法对勿忘我干花进行前处理,利用电感耦合等离子体发射光谱法(ICP-OES法),分析测定了样品中矿质元素的组成及含量。研究结果表明,从勿忘我样品中定量分析了15种矿质元素,分别为K、Na、Ti、Al、B... 采用浓HNO3-H2O2混合酸体系,以微波消解法对勿忘我干花进行前处理,利用电感耦合等离子体发射光谱法(ICP-OES法),分析测定了样品中矿质元素的组成及含量。研究结果表明,从勿忘我样品中定量分析了15种矿质元素,分别为K、Na、Ti、Al、B、Ba、Ca、Fe、Mg、Mn、P、S、Si、Sr、Zn,其中K、Na、Ca、Mg、P、S等常量元素含量均大于1000μg·g-1,未检测出Tl、Sn、Cu等微量元素以及Pb、Cd、Cr等重金属元素。10种元素的RSD值在1.76%~10.77%之间。研究结果为勿忘我的进一步开发利用提供了一定的理论依据。 展开更多
关键词 勿忘我 微波消解 矿质元素 电感耦合等离子体发射光谱法
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林茜草化学成分的研究 被引量:7
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作者 侯柏玲 王素贤 《中草药》 CAS CSCD 北大核心 2000年第7期492-494,共3页
从林茜草 Rubia sylvatica中首次分得 11个化合物 ,经理化常数和光谱分析 ,分别鉴定为 5 -羟基 -萘并 [1,2 - b]呋喃 - 4-羧酸甲酯 ( )、大叶茜草素 ( )、1-羟基 - 2 -甲基蒽醌 ( )、β-谷甾醇 ( )、胡萝卜苷 ( )、1,3,6 -三羟基 -2 -甲... 从林茜草 Rubia sylvatica中首次分得 11个化合物 ,经理化常数和光谱分析 ,分别鉴定为 5 -羟基 -萘并 [1,2 - b]呋喃 - 4-羧酸甲酯 ( )、大叶茜草素 ( )、1-羟基 - 2 -甲基蒽醌 ( )、β-谷甾醇 ( )、胡萝卜苷 ( )、1,3,6 -三羟基 -2 -甲基 -蒽醌 - 3- O- (6′-乙酰基 )新橙皮糖苷 ( )、1,3,6 -三羟基 - 2 -甲基蒽醌 - 3- O新橙皮糖苷 ( )、萘酸双糖苷 ( )、1,3,6 -三羟基 - 2 -甲基蒽醌 - 3- O- (3′,6′- O-二乙酰基 ) - α-鼠李糖 12 β- D-葡萄糖苷 ( )、1,3,6 -三羟基 - 2 -甲基蒽醌 - 3-O- (4′,6′- O-二乙酰基 ) -α-鼠李糖 12 β- D-葡萄糖苷 ( )和 1,3,6 -三羟基 - 2 -甲基蒽醌 - 3- O-β- D-葡萄糖苷 ( )。关键词 林茜草  1,3,6 -三羟基 - 2 -甲基蒽醌 - 3- O- (4′,6′- O-二乙酰基 ) - α-鼠李糖 12 β- D-葡萄糖苷  1,3,6 -三羟基- 2 -甲基蒽醌 - 3- O- β- 展开更多
关键词 林茜草 大叶茜草素(Ⅱ) β-谷甾醇(Ⅲ) 化学成分
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