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基于R-L分数阶定义的CCM Flyback变换器建模与分析
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作者 王硕禾 符屹男 +2 位作者 常宇健 杨鹏 李倩 《太阳能学报》 EI CAS CSCD 北大核心 2024年第6期217-225,共9页
针对电容电感都为分数阶这一事实,利用分数阶微积分R-L定义和状态空间平均法,对工作在电感电流连续模式(CCM)下的分数阶Flyback变换器进行建模与分析。推导CCM分数阶Flyback变换器的静态工作点和小信号传递函数以及变换器工作在CCM模式... 针对电容电感都为分数阶这一事实,利用分数阶微积分R-L定义和状态空间平均法,对工作在电感电流连续模式(CCM)下的分数阶Flyback变换器进行建模与分析。推导CCM分数阶Flyback变换器的静态工作点和小信号传递函数以及变换器工作在CCM模式下的条件。其次,讨论Caputo模型与R-L导数模型的区别,得出在R-L分数阶定义下直流静态工作点不仅与占空比相关,而且还与电感和电容的阶数以及负载有关。最后,在PSIM中搭建R-L分数阶CCM Flyback变换器电路模型,得到不同分数阶电感电容阶数下分数阶Flyback变换器输出电压和电感电流的仿真波形,通过仿真结果与理论计算结果对比,验证所建模型的正确性,得出分数阶电感电容的阶数会影响闭环控制器的设计和分数阶模型能更加精确地描述Flyback变换器的工作特性。 展开更多
关键词 dc-dc变换器 电力电子 仿真平台 R-l定义 分数阶建模
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Effects of Gynura divaricate(L.)DC on Improving Non-alcoholic Fatty Liver by Regulating NF-κB and Nrf-2/HO-1 Pathways 被引量:1
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作者 Xian YANG 《Medicinal Plant》 CAS 2021年第6期50-55,共6页
[Objectives]To study the effect and mechanism of Gynura divaricate(L.)DC(GD)on non-alcoholic fatty liver disease(NAFLD).[Methods]Male mice were randomly divided into 2 groups:normal group and model group.The mice were... [Objectives]To study the effect and mechanism of Gynura divaricate(L.)DC(GD)on non-alcoholic fatty liver disease(NAFLD).[Methods]Male mice were randomly divided into 2 groups:normal group and model group.The mice were fed with high-fat diet(HFD)for 4 weeks to induce NAFLD in the model group.The successfully modeled mice were divided into model group,positive drug group,GD high dose group,and GD low dose group.After 4 weeks of administration,the liver index,serum AST,ALT and blood lipid levels,liver tissue pathological changes,antioxidant enzymes,non-enzymatic antioxidants and inflammatory factors levels were measured in each group,and the expression of NF-κB,Nrf-2 and HO-1 in liver tissues were compared.[Results]GD significantly reduced the serum AST,ALT and blood lipid levels,increased enzyme antioxidant and non-enzymatic antioxidant content,reduced the steatosis and inflammatory infiltration of liver cells,down-regulated the level of inflammatory factors,and inhibited the expression of NF-κB,Nrf-2 and HO-1 in liver tissue.[Conclusions]GD has a protective effect on NAFLD in mice and its mechanism may be related to the regulation of NF-κB and Nrf-2/HO-1 pathways. 展开更多
关键词 Gynura divaricate(l.)dc Non-alcoholic fatty liver disease(NAFlD) Oxidative stress
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Experimental study of the anti-inflammatory activity of some compounds in Berchemia lineata(L.)DC
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作者 LIU Jun-yang TENG Hong-li +1 位作者 ZHAO Jin-mei HONG Jing 《Journal of Hainan Medical University》 CAS 2023年第11期25-30,共6页
Objective:To screen the anti-inflammatory monomeric compounds isolated from Berchemia lineata(L.)DC and explore the anti-inflammatory mechanism of some compounds based on NF-κB signaling pathway.Methods:LPS was used ... Objective:To screen the anti-inflammatory monomeric compounds isolated from Berchemia lineata(L.)DC and explore the anti-inflammatory mechanism of some compounds based on NF-κB signaling pathway.Methods:LPS was used to induce RAW264.7 to establish a model of cellular inflammatory reaction.CCK-8 method was used to detect the effect of monomer compounds on the activity of RAW264.7 cells.The release of nitric oxide(NO)in the superneant was measured by Griess method,and NO inhibition rate was calculated.The anti-inflammatory activity gradient of some monomeric compounds was also measured.The effects of monomer compound 21 on the secretion of IL-6,TNF-α,NF-κB,COX-2 and iNOS induced by LPS were detected by ELISA.Results:The concentration of monomer compound of Berchemia lineata(L.)DC.was 50μmol/L,and it was administered for 24 h.The results showed that anthraquinone compound No.19 had obvious drug toxicity,while other compounds had weak or no obvious drug toxicity.The concentration was 50μmol/L,and the drug was administered for 12 h.The results showed that all the monomer compounds could inhibit the release of NO to varying degrees,and the highest NO inhibition rate was over 90%,which showed obvious anti-inflammatory activity.NO inhibition rate of No.01 new skeleton compound can reach 70.81%.The results of anti-inflammatory activity gradient showed that the monomer compound of Berchemia lineata(L.)DC.could inhibit the release of NO in a dose-dependent manner.The results of ELISA showed that phenolic compound 21 could inhibit the secretion of IL-6,TNF-α,NF-κB,COX-2 and iNOS in RAW264.7 cells.Conclusion:The monomer compound of Berchemia lineata(L.)DC.has a certain anti-inflammatory activity,among which flavonoids and bibenzyl components isolated from this plant for the first time may be the material basis for its anti-inflammatory activity.The simple phenolic monomer compound 21 may play an anti-inflammatory role by regulating NF-κB signaling pathway. 展开更多
关键词 Tiebaojin Berchemia lineata(l.)dc RAW264.7 Anti inflammatory
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Exploring the Mechanism of Blumea balsamifera(L.)DC in Preventing and Treating Alzheimer's Disease Based on HPLC-ESI-HRMS and Network Pharmacology
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作者 Dong LI Ling LI +5 位作者 Yujie HU JiangXiong MA Wenlong ZHANG Chanyuan ZHOU Dongsheng FAN Xiaojian GONG 《Medicinal Plant》 CAS 2023年第5期10-18,共9页
[Objectives]To expose the plausible mechanism of Blumea balsamifera(L.)DC.against Alzheimer s disease via network pharmacology and HPLC-ESI-HRMS technology.[Methods]To begin with,HPLC-ESI-HRMS was employed to identify... [Objectives]To expose the plausible mechanism of Blumea balsamifera(L.)DC.against Alzheimer s disease via network pharmacology and HPLC-ESI-HRMS technology.[Methods]To begin with,HPLC-ESI-HRMS was employed to identify the components of B.balsamifera.Secondly,the potential targets of the components were identified and predicted based on chemical similarity and online databases.Thirdly,by way of topological analysis of a component-disease target interaction network,the primary candidate targets and potential active components were identified.Lastly,molecular docking analysis was used to confirm the interaction between active components and therapeutic targets.[Results]According to the final results,HPLC-ESI-HRMS identified 70 components.Out of these,20 components were potentially biologically active,and most of them were sesquiterpenoids.According to the molecular docking results,the primary active components were appropriately coordinated with the core targets,indicating a high level of pharmacodynamic activity.Thus,the sesquiterpenes present in B.balsamifera are considered potential active ingredients having multi-target and multi-pathway effects for treating Alzheimer s disease.[Conclusions]This research will provide a scientific reference for the future pharmacological activity and clinical application of B.balsamifera. 展开更多
关键词 HPlC-ESI-HRMS Alzheimer's disease Blumea balsamifera(l.)dc. Network pharmacology Molecular docking
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艾纳香油通过NF-κB非经典信号影响花生四烯酸代谢缓解LPS所致巨噬细胞的炎症反应
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作者 何贤芳 王万林 +3 位作者 王鸿颖 刘瑞秀 易琼 王鲁 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2024年第2期216-225,共10页
【目的】本文旨在探讨艾纳香油(BBO)通过核转录因子κB(NF-κB)非经典通路影响花生四烯酸(AA)代谢通路发挥抗炎作用。【方法】采用豚鼠离体回肠法检测BBO对慢反应物质(SRS-A)生成的影响,ELISA法检测BBO对脂多糖(LPS)诱导巨噬细胞前列腺... 【目的】本文旨在探讨艾纳香油(BBO)通过核转录因子κB(NF-κB)非经典通路影响花生四烯酸(AA)代谢通路发挥抗炎作用。【方法】采用豚鼠离体回肠法检测BBO对慢反应物质(SRS-A)生成的影响,ELISA法检测BBO对脂多糖(LPS)诱导巨噬细胞前列腺素E_(2)(PGE_(2))及白三烯B_(4)(LTB_(4))产生的影响,qRT-PCR检测BBO对LPS诱导巨噬细胞COX-2、5-LOX、FLAP和RelB表达的影响,Western blot检测BBO对NF-κB非经典通路蛋白肿瘤坏死因子受体作用因子3(TRAF3)、肿瘤坏死因子受体作用因子2(TRAF2)、NF-κB诱导激酶(NIK)、p100和RelB浓度的影响。【结果】在1mg·mL^(-1)的BBO药物浓度下减弱了豚鼠回肠的收缩张力(P<0.001),对SRS-A的生成抑制率达到65.34%;与LPS模型组相比,BBO在40-80μg·mL^(-1)浓度下降低AA代谢通路中PGE_(2)(P<0.05)和LTB_(4)(P<0.05)的浓度,降低COX-2(P<0.05)、5-LOX(P<0.05)和FLAP(P<0.05)的表达;此外,40-80μg·mL^(-1)浓度下BBO还降低LPS导致的NF-κB非经典通路中TRAF3(P<0.05)、TRAF2(P<0.05)和NIK(P<0.05)的浓度,进一步抑制p100蛋白的磷酸化(P<0.05),同时抑制转录因子RelB的表达(P<0.05)和RelB蛋白的水平(P<0.05),而BBO自身不引起这些基因与蛋白的变化。【结论】BBO可能通过抑制NF-κB非经典信号中调节蛋白TRAF3和TRAF2,转录因子RelB的浓度,造成NIK蛋白的诱导激酶作用受到抑制,进一步抑制了p100蛋白的磷酸化及其与转录因子RelB的结合,从而影响到下游AA通路中重要限速酶COX-2、5-LOX和FLAP的表达与炎症介质PGE_(2)和LTB_(4)的水平发挥抗炎作用。 展开更多
关键词 艾纳香油 脂多糖 NF-κB非经典通路 花生四烯酸代谢 抗炎作用
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加味青蒿鳖甲汤对髓系MRD-L患者CD_(34)^+细胞源DC诱导过程中IL-12的影响 被引量:1
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作者 刘健 黄礼明 +7 位作者 唐志宇 宋益青 仇江辉 赵国静 马武开 严鲁萍 姚宇红 李秀军 《辽宁中医杂志》 CAS 2014年第3期400-402,共3页
目的:探讨加味青蒿鳖甲汤对树突细胞(DC)诱导和对IL-12分泌的影响。方法:本研究采用体外培养的方法,用含不同剂量(高、中、低)加味青蒿鳖甲汤动物血清联合细胞因子、不含药血清联合细胞因子及单纯用细胞因子,共同培养缓解期急性髓系白血... 目的:探讨加味青蒿鳖甲汤对树突细胞(DC)诱导和对IL-12分泌的影响。方法:本研究采用体外培养的方法,用含不同剂量(高、中、低)加味青蒿鳖甲汤动物血清联合细胞因子、不含药血清联合细胞因子及单纯用细胞因子,共同培养缓解期急性髓系白血病(AML-CR)患者骨髓中分离提取的CD+34细胞,诱导其成为DC,观察各组在不同阶段对DC成熟的影响,以及各组血清中IL-12的分泌变化。结果:含药血清均能上调DC表面特征性分子及共刺激分子CD80、CD83、CD86表达水平,较单纯细胞因子组比较有显著性差异(P<0.01),且含中剂量药血清更能促进DC分泌IL-12(P<0.01)。结论:联合细胞因子的含加味青蒿鳖甲汤的血清,可使来源AML-CR骨髓的CD+34,在体外比单纯用细胞因子诱导培养DC能够更好地促进DC的生长、成熟和分化,并能促进DC分泌IL-12,增加抗肿瘤作用。 展开更多
关键词 加味青蒿鳖甲汤 MRD—l CD34%PlUS% dc Il-12
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RF/DC溅射316L/SiO_2复合膜力学性能与显微结构的研究 被引量:1
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作者 温伟祥 胡社军 +6 位作者 曾鹏 吴起白 谢光荣 黄拿灿 胡显奇 盛钢 盛忠 《真空》 CAS 北大核心 2001年第2期30-32,共3页
利用射频 /直流磁控溅射法制备了 316 L不锈钢 / Si O2 复合薄膜 ,并对其组织、相结构和力学性能进行了测试分析。结果表明 :直流磁控溅射 316 L不锈钢薄膜呈柱状晶结构 ,主要由 Fe- Cr和 - Fe相构成 ,在 Fe-Cr(110 )晶面出现明显择优... 利用射频 /直流磁控溅射法制备了 316 L不锈钢 / Si O2 复合薄膜 ,并对其组织、相结构和力学性能进行了测试分析。结果表明 :直流磁控溅射 316 L不锈钢薄膜呈柱状晶结构 ,主要由 Fe- Cr和 - Fe相构成 ,在 Fe-Cr(110 )晶面出现明显择优取向 ;由于 Si O2 的掺合 ,使 316 L不锈钢 / Si O2 复合薄膜柱状晶变细小 ,出现明显的二次柱状晶 ,Fe- Cr的 (110 )晶面择优取向消失 ,而 Fe- Cr的 (2 11)晶面衍射峰强度明显增强 ,316不锈钢膜硬度明显高于 316 L块体 ,掺入 Si O2 的金属 展开更多
关键词 RF/dc溅射 316l不锈钢 二氧化硅 金属基陶瓷增强复合膜 显微结构 力学性能
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DC-SIGN和L-SIGN与丙型肝炎病毒感染
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作者 陈秋莉 戚中田 《生命的化学》 CAS CSCD 北大核心 2005年第4期287-290,共4页
近年来发现的树突细胞特异性细胞间黏附分子-3-结合非整合素分子(dendritic cell-specific ICAM-3-grabbing nonintegrin,DC-SIGN)及其相关分子L-SIGN与丙型肝炎病毒的致病机制及其感染的慢性化有关,该文介绍DC-SIGN和L-SIGN的发现、生... 近年来发现的树突细胞特异性细胞间黏附分子-3-结合非整合素分子(dendritic cell-specific ICAM-3-grabbing nonintegrin,DC-SIGN)及其相关分子L-SIGN与丙型肝炎病毒的致病机制及其感染的慢性化有关,该文介绍DC-SIGN和L-SIGN的发现、生物学特点及其与丙型肝炎病毒相互作用的研究进展。 展开更多
关键词 丙型肝炎病毒 受体 感染 dc—SIGN l—SIGN
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不同产地射干药材水溶性成分的HPLC指纹图谱及其含量差异 被引量:1
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作者 吴佳 王珊 《沈阳药科大学学报》 CAS CSCD 北大核心 2023年第5期593-600,共8页
目的 采用高效液相色谱(HPLC)指纹图谱对不同产地射干药材水溶性成分的相似度及含量差异进行分析,以期为射干的临床安全应用提供参考。方法 建立不同产地射干药材水溶性成分的HPLC指纹图谱,对15个产地射干药材的水溶性成分进行相似度评... 目的 采用高效液相色谱(HPLC)指纹图谱对不同产地射干药材水溶性成分的相似度及含量差异进行分析,以期为射干的临床安全应用提供参考。方法 建立不同产地射干药材水溶性成分的HPLC指纹图谱,对15个产地射干药材的水溶性成分进行相似度评价,并对不同产地射干药材的射干苷、野鸢尾苷等成分进行方法学考察与含量测定,结合聚类分析法、主成分分析法,综合评价不同产地射干药材的质量。结果 HPLC指纹图谱分析显示15个产地射干药材的相似度均大于90.0%。在射干药材水溶性成分含量测定中,射干苷含量以产地为湖北团风最佳;野鸢尾苷含量以产地为湖北兴山最佳。主成分分析认为产地为湖北团风的射干药物品质最佳。结论 HPLC指纹图谱可客观、准确地评价不同产地射干药材水溶性成分的含量差异,为射干药材的临床安全应用与新药资源开发提供理论依据。 展开更多
关键词 射干 水溶性成分 高效液相色谱 指纹图谱 含量
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L-LLC谐振型双向DC-DC变换器的复合最优轨迹控制策略研究 被引量:11
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作者 鲁静 同向前 +2 位作者 张嘉翔 申明 尹军 《电工技术学报》 EI CSCD 北大核心 2020年第S01期60-69,共10页
针对L-LLC谐振型双向DC-DC变换器提出了比例-积分-谐振(PID)控制与最优轨迹控制相结合的复合最优轨迹控制策略。在系统稳态时采用PID控制减小稳态误差保持输出电压恒定;当出现负载跳变时,采用最优轨迹控制改变开关管的频率,使其在最短... 针对L-LLC谐振型双向DC-DC变换器提出了比例-积分-谐振(PID)控制与最优轨迹控制相结合的复合最优轨迹控制策略。在系统稳态时采用PID控制减小稳态误差保持输出电压恒定;当出现负载跳变时,采用最优轨迹控制改变开关管的频率,使其在最短时间内重新达到稳态。该控制策略实现了输入侧开关管的零电压开通和输出侧整流管的零电流关断,精确预测了负载突变时的开关管导通时间,显著提高了变换器的动态性能且减小了运算的复杂度。仿真和实验结果表明,采用复合最优轨迹控制策略显著改善了L-LLC谐振型双向DC-DC变换器的动态性能。 展开更多
关键词 l-llC 双向变换器 轨迹控制 复合控制 状态平面法
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漏芦通过TLR4/NF-κB通路抑制脂多糖诱导的小鼠乳腺上皮细胞炎症反应
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作者 刘莉莉 陈敏 《饲料工业》 北大核心 2023年第17期92-97,共6页
为探讨漏芦醇提物(RUEE)对脂多糖(LPS)诱导的小鼠乳腺上皮细胞(HC11细胞)的抗炎作用及机制,试验利用RUEE(80μg/mL)、LPS(1μg/mL)单独处理以及RUEE(80μg/mL)+LPS(1μg/mL)共处理HC11细胞,采用荧光定量PCR检测炎性细胞因子及Toll样受体... 为探讨漏芦醇提物(RUEE)对脂多糖(LPS)诱导的小鼠乳腺上皮细胞(HC11细胞)的抗炎作用及机制,试验利用RUEE(80μg/mL)、LPS(1μg/mL)单独处理以及RUEE(80μg/mL)+LPS(1μg/mL)共处理HC11细胞,采用荧光定量PCR检测炎性细胞因子及Toll样受体4(TLR4)mRNA表达水平,采用Western blotting检测核转录因子κB(NF-κB)通路关键因子的蛋白表达量。结果表明:LPS诱导可明显提高HC11细胞肿瘤坏死因子-α(TNF-α)、环氧合酶-2(COX-2)、白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)的mRNA表达水平(P<0.05);明显上调TLR4 mRNA表达及NF-κB p65和NF-κB抑制蛋白α(IκBα)的磷酸化水平(P<0.05)。RUEE预处理可显著降低LPS诱导的HC11细胞TNF-α、COX-2、IL-6、IL-1β的mRNA表达(P<0.05);显著下调TLR4 mRNA表达及NF-κB p65和IκBα的磷酸化水平(P<0.05)。由此可知漏芦醇提物可通过抑制TLR4/NF-κB通路的激活,下调相关炎性细胞因子的过度表达而缓解LPS诱导的乳腺上皮细胞炎症反应。 展开更多
关键词 漏芦 乳腺上皮细胞 脂多糖 炎症反应 NF-ΚB信号通路
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Studies on the Anti-inflammatory Activity of Three Extraction Processes of Bidens alba(L.) DC 被引量:1
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作者 Qiyun GAO Yiwei QIN Minggui YUAN 《Medicinal Plant》 CAS 2018年第6期68-71,共4页
[Objectives] To compare the anti-inflammatory activities of three extraction processes of the exotic plant Bidens alba(L.) DC in Lingnan(south of the Five Ridges in China).[Methods]The alcohol extracts of B.alba(L.) D... [Objectives] To compare the anti-inflammatory activities of three extraction processes of the exotic plant Bidens alba(L.) DC in Lingnan(south of the Five Ridges in China).[Methods]The alcohol extracts of B.alba(L.) DC were extracted and separated with petroleum ether,chloroform and ethyl acetate respectively.The anti-inflammatory activity experiment of these three extracts was carried out with the RAW264.7 inflammatory model of mouse macrophages in vitro.[Results]When the concentration was 0.05-1.6 mg/L,the petroleum ether extract of B.alba(L.) DC produced strong inhibitory effects on nitric oxide(NO) release of RAW264.7 macrophages induced by LPS;the inhibition of ethyl acetate extract was weak,and the chloroform extract showed no significant inhibition.[Conclusions]Petroleum ether is the best extractant for active anti-inflammatory ingredients of B.alba(L.) DC. 展开更多
关键词 BIDENS alba(l.)dc Macrophage RAW264.7 ANTI-INFlAMMATORY activity Petroleum ETHER
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Studies on the Analgesic Activity and Acute Toxicities of Bidens alba(L.) DC
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作者 Minggui YUAN Qiyun GAO +4 位作者 Rong XIANG Ting HUANG Danni YU Zhihong XU Xinyu PENG 《Agricultural Biotechnology》 CAS 2019年第3期174-176,共3页
[Objectives]This study was conducted to investigate the analgesic effects and acute toxicities of Bidens alba (L.) DC.[Methods]The alcohol extract of B.alba (L.) DC was extracted and separated with petroleum ether and... [Objectives]This study was conducted to investigate the analgesic effects and acute toxicities of Bidens alba (L.) DC.[Methods]The alcohol extract of B.alba (L.) DC was extracted and separated with petroleum ether and chloroform successively.The acute toxicities of the two extracts on mice were measured,and then the analgesic effects were measured with writhing pain model induced by acetic acid.[Results]No mice died when the crude dosages of B.alba (L.) DC from petroleum ether extract and chloroform extract were 5 016 and 5 100 mg/kg,respectively.When the petroleum ether extract was 60.0 mg/kg,the percentage of twisted mice induced by acetic acid was 40%,the analgesic rate was 77.5%,and the time of the first writhing was (294.0±165.8) s;when the chloroform extract was 20.0 mg/kg,the percentage of twisted animals was 55.6%,the analgesic rate was 51.5%,and the time of the first writhing was (273.8 ±153.4) s;and when the chloroform extract was 4.0 mg/kg,the percentage of twisted animals was 40%,and the analgesic rate was 62.1%,and the time of the first writhing was (370.6±231.3) s.[Conclusions]The petroleum ether extracts and chloroform extracts of B.alba (L.) DC have good analgesic effects and no acute toxicities. 展开更多
关键词 BIDENS AlBA (l.) dc Mouse Analgesic effect ACUTE toxicity Petroleum ether CHlOROFORM
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小身材 大智慧 Sony Cyber-shot L1 DC
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《数字生活》 2005年第1期40-40,共1页
近期,索尼(中国)有限公司隆重推出了最新款拥有410万有效像素及3倍光学变焦的数码相机—Cyber-shot L1,该款产品纤巧别致、简单易用,更为时尚女性所推崇。
关键词 有效像素 数码相机 Sony Cyber-shot l1 dc 场景模式 光学变焦 自动对焦
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Simultaneous Determination of Six Components in Wanjinxiang Shushuang Ointment by QAMS
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作者 Yanni MAO Lin YANG +3 位作者 Xiaoyao XIE Jinyan JIA Qing WU Cun WU 《Medicinal Plant》 CAS 2023年第5期1-5,共5页
[Objectives]To regulate the quality of Wanjinxiang Shushuang Ointment through simultaneously quantifying menthol,camphor,1,8-cineole,linalool,borneol and caryophyllene oxide by QAMS(quantitative analysis of multi-comp... [Objectives]To regulate the quality of Wanjinxiang Shushuang Ointment through simultaneously quantifying menthol,camphor,1,8-cineole,linalool,borneol and caryophyllene oxide by QAMS(quantitative analysis of multi-components by single-marker).[Methods]The method was performed using an Agilent DB-WAX(30 m×0.32 mm,0.25μm)polyethylene glycol chromatographic column;with nitrogen employed as a carrier gas.The constant pressure was 4.73 psi;and the injection temperature was 240℃,with a shunt ratio:of 10:1;The hydrogen flame ion detector with a detector temperature of 240℃;the injection volume was 0.3μL.To verify the accuracy and applicability of QAMS,the results were compared with those obtained using the internal standard method(naphthalene).[Results]In Wanjinxiang Shushuang Ointment,menthol,camphor,1,8-cineole,linalool,borneol,caryophyllene oxide and naphthalene were well separated by the same chromatography with good linearity in their respective ranges(R≥0.9992).The average recoveries were 99.66%,101.03%,98.07%,98.24%,101.39%,and 103.39%with RSD s of 0.69%,1.52%,1.25%,1.94%,1.44%,and 2.74%,respectively.The QAMS is similar to the internal standard method.[Conclusions]This simple,accurate method with high precision,separation and reproducibility can serve as a reference for the quality control of Wanjinxiang Shushuang Ointment. 展开更多
关键词 Wanjinxiang Shushuang Ointment Blumea balsamifera(l.)dc. Chemical component Quantitative analysis of mult-components by single-marker(QAMS) Quality control
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白背三七叶中吡咯里西啶生物碱的LC-MS^n检测 被引量:16
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作者 李丽梅 张涵庆 +3 位作者 吕寒 李维林 徐德然 郭巧生 《植物资源与环境学报》 CAS CSCD 2008年第2期79-80,共2页
The pyrrolizidine alkaloids(PAs) in leaf of Gynura divaricata(L.) DC.was analyzed by LC-MSn technique.The result shows that two hepatotoxic pyrrolizidine alkaloids(HPAs) are detected from the methanol extract of G.div... The pyrrolizidine alkaloids(PAs) in leaf of Gynura divaricata(L.) DC.was analyzed by LC-MSn technique.The result shows that two hepatotoxic pyrrolizidine alkaloids(HPAs) are detected from the methanol extract of G.divaricata leaf,with relative molecular weight of 335 and 365,respectively and lower content.The constituent with relative molecular weight 335 is a retronecine-type alkaloid,and identified as integerrimine;another constituent with relative molecular weight 365 is an otonecine-type alkaloid,speculated to be isomer of usaramine or 18-hydroxyinterrimine. 展开更多
关键词 白背三七 吡咯里西啶生物碱 全缘千里光碱 液相色谱与多级质谱联用法(lC—MS^n)
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HPLC法测定链荚豆根中水杨酸的含量 被引量:8
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作者 刘洪蛟 雷鸣 +2 位作者 胡艳丽 俞嘉 郭兴杰 《沈阳药科大学学报》 CAS CSCD 北大核心 2013年第5期356-358,共3页
目的建立测定链荚豆根中水杨酸含量的方法。方法采用HPLC法。色谱柱为Elite C18柱(200 mm×4.6 mm,5μm),流动相为乙腈-体积分数0.8%乙酸水溶液(体积比25∶75),流速为1.0mL.min-1。结果水杨酸质量浓度在2.625~21.00 mg.L-1内与峰... 目的建立测定链荚豆根中水杨酸含量的方法。方法采用HPLC法。色谱柱为Elite C18柱(200 mm×4.6 mm,5μm),流动相为乙腈-体积分数0.8%乙酸水溶液(体积比25∶75),流速为1.0mL.min-1。结果水杨酸质量浓度在2.625~21.00 mg.L-1内与峰面积呈良好的线性关系(r=0.999 6),平均加样回收率为99.4%,RSD为2.1%。结论本方法专属、简便、准确、重现性好,可用于测定链荚豆根中水杨酸的含量。 展开更多
关键词 链荚豆 水杨酸 HPlC 含量测定
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高效液相色谱法测定不同部位两面针原植物中L-芝麻脂素和L-细辛脂素的含量 被引量:17
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作者 张守尧 周本杰 汪艳 《第一军医大学学报》 CSCD 北大核心 2002年第7期654-655,共2页
目的 建立两面针原植物中L-芝麻脂素和L-细辛脂素的测定方法,并测定两面针不同部位两者的含量。方法 采用高效液相色谱法(HPLC),色谱柱为HYPERSIL BDS C18,流动相为乙腈:水(50:50),检测波长287nm。结果 L-芝麻脂素和L-细辛脂... 目的 建立两面针原植物中L-芝麻脂素和L-细辛脂素的测定方法,并测定两面针不同部位两者的含量。方法 采用高效液相色谱法(HPLC),色谱柱为HYPERSIL BDS C18,流动相为乙腈:水(50:50),检测波长287nm。结果 L-芝麻脂素和L-细辛脂素的平均回收率和相对标准差分别为100.13%、1.61%和101.24%、1.46%。结论 此法可用于两面针的质量控制。两面针原植物根部的被测成分含量最高。 展开更多
关键词 高效液相色谱法 两面针原植物 l-芝麻脂素
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复合频率直流逆变电路中L/C的域值计算与研究 被引量:3
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作者 魏丽君 陈一平 +1 位作者 戴涛 何华 《物探化探计算技术》 CAS CSCD 2010年第3期270-273,共4页
大功率复合频率电源是电法勘探中必需的信号源。大多数电法勘探仪器信号源的控制电路都采用大功率IGBT模块设计,因为IGBT模块具有输入阻抗高,速度快,通态压降低,热稳定性好,以及高电压和大电流的优点,但同时也存在控制电路较复杂,体积大... 大功率复合频率电源是电法勘探中必需的信号源。大多数电法勘探仪器信号源的控制电路都采用大功率IGBT模块设计,因为IGBT模块具有输入阻抗高,速度快,通态压降低,热稳定性好,以及高电压和大电流的优点,但同时也存在控制电路较复杂,体积大,抗干扰能力较差等缺点。这里重点介绍一种采用可控硅BT151(晶闸管)作为主要逆变器件,通过对L/C储能器件域值的合理选择,研究与设计了一套性能稳定,复合频率直流逆变电路,为电法勘探仪器采用大功率SCR器件提供了研究基础。该电路设计成果已成功的应用在国家"十一五"支撑课题项目中。 展开更多
关键词 复合频率 直流逆变电路 l/C的域值计算
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GC-MS-DC联用法研究山薄荷石油醚部位的化学成分 被引量:2
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作者 胡浩斌 郑尚珍 +2 位作者 宋志军 黄彬弟 沈序维 《西北师范大学学报(自然科学版)》 CAS 2004年第3期43-45,63,共4页
利用GC MS DC联用法研究了山薄荷石油醚部位的化学成分,在最佳分析条件下,共分离出65个峰,鉴定出56个化学成分.其中主要成分为:香荆芥酚(34 26%)、百里香酚(16 00%)、(Z,Z,Z) 9,12,15 十八碳三烯酸甲酯(4 82%)、角鲨烯(4 36%)、7,10,13... 利用GC MS DC联用法研究了山薄荷石油醚部位的化学成分,在最佳分析条件下,共分离出65个峰,鉴定出56个化学成分.其中主要成分为:香荆芥酚(34 26%)、百里香酚(16 00%)、(Z,Z,Z) 9,12,15 十八碳三烯酸甲酯(4 82%)、角鲨烯(4 36%)、7,10,13 十六碳三烯酸甲酯(3 46%)、N 丁吡咯(3 29%)、(Z,Z) 9,12 十八碳二烯酸甲酯(1 96%)、α 萜品醇(1 96%)、十六酸甲酯(1 90%)、邻苯二甲酸二丁酯(1 66%)、罗勒烯(1 13%)等. 展开更多
关键词 山薄荷 化学成分 GC-MS-dc联用法 百里香酚 香荆芥酚
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