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1.
本文用反相高效液相色谱法测定垫状卷柏药材中的穗花杉双黄酮.选用Puraspher star RP-C18色谱柱(250 mm×4.6 mm,5μm),以甲醇-0.1%磷酸水溶液(65:35)为流动相,流速为0.8 mL/min,检测波长337 nm,柱温25℃进行检测.结果显示,穗花杉双黄酮的含量在0.038~0.342 μg范围内时进样量与峰面积积分值呈良好的线性关系,r=0.9999,平均回收率为101.2%,RSD为2.3%(n=6).该方法测定垫状卷柏药材中的穗花杉双黄酮含量灵敏、准确、重现性好.  相似文献   

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从卷柏(Selaginella tamariscina(Beauv.)Spring)中分离得到10个化合物,运用波谱手段分别鉴定为se-laginellin(1)、selaginellin A(2)、selaginellin B(3)、穗花杉双黄酮(4)、sequoiaflavone(5)、去甲银杏双黄酮(6)、银杏双黄酮(7)、异银杏双黄酮(8)、扁柏双黄酮(9)、异柳杉双黄酮(10)。其中化合物1、5和8为首次从该植物中分离得到。化合物1,4,7,8和9显示出选择性的细胞毒活性。  相似文献   

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采用星点设计-效应面法优化杉木枝叶中穗花杉双黄酮和金松双黄酮的提取工艺.以乙醇体积分数、料液比、提取时间为自变量,穗花杉双黄酮和金松双黄酮转移率的归一化值为因变量,通过对自变量与因变量的二次多项式拟合,采用效应面法选取较优的工艺条件,并进行预测分析.最终确定穗花杉双黄酮和金松双黄酮的最佳提取工艺为:乙醇体积分数为50%,料液比为1∶13,超声提取3次,每次提取60 min,最佳工艺验证结果与模型预测值相差-2.55%.结果表明:星点设计-效应面法优选的穗花杉双黄酮和金松双黄酮的提取工艺,方法简便、可靠.  相似文献   

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《蛇志》2020,(3)
目的建立HPLC测定双金花茶中免疫活性分子山奈酚含量的方法。方法采用Kromasil C18(4.6 mm×200 mm,5μm)色谱柱;流动相:甲醇∶0.1%醋酸水溶液(70∶30);流速:1.0 ml/min;检测波长:370 nm;柱温:25℃。结果山奈酚在进样量0.04~0.40μg(r=0.9999)范围内呈良好线性关系,平均加样回收率为100.00%,RSD为0.07%(n=6)。结论 HPLC法简便易行,准确可靠,可用于双金花茶中免疫活性分子山奈酚含量测定。  相似文献   

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研究了江南卷柏提取物的石油醚脱脂工艺。以残渣穗花杉双黄酮提取量和石油醚浸膏得率为参考指标,采用HPLC进行定量分析,通过正交试验法优选脱脂工艺。最佳脱脂工艺为用6倍量石油醚回流提取2次,每次提取时间1h。该脱脂工艺稳定可行。  相似文献   

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目的:比较新疆戈宝麻花、种子、叶片中芦丁的含量。方法:采用回流提取法提取芦丁,高效液相层析法法测定新疆戈宝麻不同部位中芦丁的含量。色谱柱为Eclipse-C18柱(4.6 mm×150 mm, 5 um);流动相为乙腈-0.25%磷酸溶液(V/V,14.5∶85.5);流速为1.0 mL/min;柱温为30℃;检测波长为360 nm;进样量为20 uL。结果:芦丁含量在0.01~0.1 mg/mL范围内与峰面积呈良好的线性关系,相关系数为0.993 6;其中花、种子、叶片中芦丁得率分别为:0.094%、0.014%、0.6%。结论:新疆戈宝麻不同部位芦丁的含量分布为:叶﹥花﹥种子,上述结果可为增加戈宝麻新药源和新的药用部位开发利用提供有力依据。  相似文献   

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本文研究兖州卷柏Selaginella involvens Spring.的化学成分及体外抗菌活性.运用反复色谱层析进行纯化分离得到7个化合物,经波谱解析结合理化鉴定确定化合物结构为:正十六烷酸(1),正十八烷酸(2),β-谷甾醇(3),豆甾醇(4),穗花杉双黄酮(5),β-D-glucopyranoside,(3β)-cholest-5-en-3yl(6),β-香树脂醇(7).化合物1~7均首次从该植物中分离得到,6和7首次从该属植物中分离得到.此外研究了化合物5、6和7的体外抗菌活性.化合物5、6和7可能为兖州卷柏抗肺炎病菌的主要物质基础.  相似文献   

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利用质谱引导的自动纯化分离系统对垫状卷柏95%乙醇提取物的乙酸乙酯萃取部分进行选择性分离纯化双黄酮类、炔酚类化合物。并利用MS、^(1)H NMR、^(13)C NMR、2D NMR等光波谱分析方法确定结构,结果得到四个双黄酮类化合物,分别为扁柏双黄酮(1)、异柳杉双黄酮(2)、苏铁双黄酮(3)、穗花杉双黄酮(4),七个炔酚类化合物,分别为selaginellin(5)、selaginpulvilin A(6)、selaginpulvilin B(7)、selaginellin O(8)、selaginellin E(9)、selaginellin A(10)、selaginellin B(11)。采用MTT法评价了化合物1~11体外抑制人非小细胞肺癌细胞(NSCLC)H322增殖活性,结果表明,除化合物4和7外,其他化合物对人非小细胞肺癌细胞H322有不同程度的增殖抑制活性,其中化合物3和10抑制作用较强,IC_(50)值分别为16.70和9.54μmol/L。  相似文献   

9.
李敏  杨滢  王喆之  李翠芹 《生物磁学》2011,(Z1):4722-4724
目的:建立九节菖蒲中琥珀酸含量的HPLC测定法。方法:采用Kromasil C18色谱柱(150 mm×4.6 mm,5μm);甲醇-0.02mol/L KH2PO4缓冲液(7:93)(pH 2.5)为流动相;流速0.5 mL/min;柱温为30℃;检测波长为214 nm。结果:琥珀酸在4~48μg范围内具有良好的线性关系,平均加样回收率为99.15%。九节菖蒲样品中的琥珀酸含量,以干燥品计为0.200%~0.318%。结论:该方法可行,重复性好,可用于九节菖蒲中琥珀酸含量的测定。  相似文献   

10.
目的:利用高效液相色谱法建立安宫牛黄丸中黄芩苷和黄芩素含量的测定方法.方法:采用高效液相色谱法.以VenusilASB-C18柱(4.6mm×250mm,5μm)为色谱柱;流动相分别为:乙腈-0.4%磷酸(21:79;35:65);检测波长:277 nm;流速:1 ml.min-1.结果:安宫牛黄丸中黄芩苷和黄芩素的含量分别为0.148%;0.0169%.结论:该方法准确、灵敏度高、重现性好,可以作为安宫牛黄丸中黄芩苷和黄芩素含量的测定方法.  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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