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目的:建立HPLC法测定海南黄灯笼椒等辣椒的辣椒素含量。方法:采用Diamonsil C18柱(4.6 mm×250mm,5μm),流动相为甲醇-水(体积比70∶30),流速为1.0 mL/min,检测波长为230 nm,柱温:30℃,外标法定量。结果:辣椒素的线性关系良好,线性范围2.0μg/mL~20.0μg/mL,r=0.9990;精密度、稳定性实验的RSD均低于2%;平均回收率100.8%(n=9),RSD=1.87%。对海南黄灯笼椒等7个品种辣椒的辣椒素含量进行测定,海南黄灯笼椒的辣椒素含量最高。结论:该方法简便快捷,可用于辣椒中辣椒素含量的测定;海南黄灯笼椒辣椒素含量最高,这些信息可为海南黄灯笼辣椒的研究开发提供参考。 相似文献
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建立高效液相色谱法测定含量和含量均匀度的方法。采用SHIMADZU CLC-ODS色谱柱,以乙睛-水-冰醋酸(380∶120∶0.2)为流动相,234nm波长处检测。氟伐他汀钠在41μg/mL~328μg/mL浓度范围内线性关系良好(r=0.9998),平均回收率为100.5%,相对标准偏差(relative standaral deviation,RSD)0.5%(n=9)。本方法具有简单,柱效高,经济等优点。 相似文献
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以酵母功能性β-1,3/1,6-葡聚糖为对照品,利用苯胺蓝和β-1,3/1,6-葡聚糖特异结合荧光特性,研究了葡聚糖荧光法测定时的各影响因素,建立了荧光法测定食药用菌功能性β-葡聚糖的方法。pH9.6缓冲液,80℃条件下避光反应15min,室温30min冷却后,398nm激发波长,508nm发射波长,20℃下进行荧光测定。在测定浓度2-20μg/mL范围内,荧光强度与浓度具有良好的线性关系(R2=0.9977),其中检出限为45μg/L,测定精密度和加样回收率良好,相对标准偏差(RSD)分别为1.86%和3.40%,并与酶法进行了比对验证,一致性良好,且荧光法更为节约时间和成本,并对灰树花菌、巴氏蘑菇、香菇和鲍氏针层孔菌四种食药用菌β-葡聚糖提取样品进行了葡聚糖纯度和提取率测定。 相似文献
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为了评价人面果叶子、根部、果实提取物体外抗糖尿病活性,相应测定了其石油醚提取物(PFr.)、乙酸乙酯提取物(EFr.)、正丁醇提取物(BFr.)、水提取物(WFr.)的α-葡萄糖苷酶与α-淀粉酶抑制活性,以及HepG2细胞的促葡萄糖消耗能力。果实乙酸乙酯提取物(IC50=17.81±1.09μg/mL)、叶子乙酸乙酯提取物(IC50=18.60±1.56μg/mL)、根部乙酸乙酯提取物(IC50=14.05±0.24μg/mL)、根部正丁醇提取物(IC50=13.01±0.38μg/mL)显示了较好的α-葡萄糖苷酶抑制活性(acarbose IC50200μg/mL)。而根部乙酸乙酯与正丁醇提取物在600μg/mL的浓度下就显示了90%的α-葡萄糖苷酶抑制率,在1.5 mg/mL的浓度下显示了90%的α-淀粉酶抑制率。在促葡萄糖消耗试验中,果实乙酸乙酯提取物在浓度为7.5~30 mg/mL时显示了很好的促HepG2细胞葡萄糖消耗能力(P0.001),叶子乙酸乙酯提取物、根部正丁醇与乙酸乙酯提取物的促葡萄糖消耗率达到了3.08、3.12、1.93,仅次于果实乙酸乙酯提取物(3.91)。此次研究为人面果抗糖尿病活性开发提供一定理论基础。 相似文献
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以C_(18) ODS色谱柱为分析柱,甲醇-水-三乙胺(体积比70:30:0.3,含庚烷磺酸钠10mmol/L,用磷酸调pH 4.0)为流动相,260 nm为检测波长,用反相高效液相色谱法测定了双唑泰软膏中甲硝唑、克霉唑和醋酸氯己定3个组分的含量。测定结果表明:甲硝唑、醋酸氯己定和克霉唑分别在3.92~39.2μg/mL,3.32~33.2μg/mL和1.64~16.4μg/mL质量浓度范围内,与峰面积呈良好的相关性(r=0.999 9、r=0.999 4和r=0.999 1),平均回收率分别为99.95%、101.14%和99.47%(n=9)。该法快速、方便,分离度好,辅料无干扰,适用于该复方制剂中3种成分的同时测定。 相似文献
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高效液相色谱法测定辣椒干中辣椒素的含量 总被引:5,自引:0,他引:5
本文建立了简便、快速的分离测定辣椒干中辣椒素含量的高效液相色谱法.HPC的条件Burospher-100 C18柱(I.D.250 mm×4.6 mm,5μm);流动相为甲醇-水(7030,V/V);流速为0.6 mL/min;检测波长为280 nm.在上述条件下,辣椒素在1.01~121.2 mg/L的范围内线性关系良好,线性相关系数γ=0.9994;实验结果表明,该方法的相对标准偏差在1.38%(n=6)以内,平均回收率为99.88%. 相似文献
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超声提取-分光光度法测定浙江雪胆中总皂苷含量 总被引:4,自引:0,他引:4
超声波提取浙江雪胆总皂苷,运用分光光度法对浙江雪胆中总皂苷的含量进行测定。正交设计优选比色条件,以齐墩果酸-28-O--αL-鼠李吡喃糖基(1→4)--βD-葡萄吡喃糖基(1→6)--βD-葡萄吡喃糖甙(cussonodide B)为标准品,利用香草醛-醋酸显色体系,在550 nm处检测。浓度在3.43~17.17μg/mL范围内呈良好的线性关系,其回归方程为A=0.03350*C(μg/mL)-0.06595,相关系数R=0.9995,浙江雪胆中总皂苷的含量为0.34%,加样回收率99.29%,RSD=0.99%。本方法简便、快速、准确、可靠。 相似文献
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目的:建立一种准确测定萹蓄中总黄酮含量的新方法.方法:以芦丁为标准样品,用荧光分光度法测得其荧光强度、绘制标准曲线.用60%乙醇加热回流提取萹蓄有效成分,在相同的条件下测定样品中总黄酮的荧光强度,根据回归方程求得其含量.结果:当芦丁的浓度范围在0μg/mL~22μg/mL时,荧光强度和芦丁浓度具有良好的线性关系,线性回归方程Y=-8.973X 22.581,相关系数r=0.9771.篇蓄中总黄酮的平均含量17.05μg/mL,所得率为6.82%.结论:用荧光分光度法测定萹蓄中总黄酮的含量,操作简便、快速、准确,建议推广应用. 相似文献
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建立高效液相色谱法测定鸢尾苷元磺酸钠(4′,5,7-三羟基-6-甲氧基异黄酮-5′-磺酸钠)及其制剂泰克吉宁注射液的含量及有关物质。采用C18色谱柱(150×4.6mm,5μm),流动相为甲醇-5%醋酸水(80:20),流速为1.0mL/min,检测波长为263nm。鸢尾苷元磺酸钠在11~100μg/mL范围内线性关系良好,回归方程Y=43.3609X-1.5973(r=0.99998),平均回收率为99.77%(n=9)。最低检测限为0.052μg/mL,与有关物质分离良好。本法快速、简便、准确,专属性强。 相似文献
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实验研究了三种光敏剂:血卟啉衍生物(HpD)、癌光啉(PsD-007)和血啉甲醚(HMME),在光敏剂浓度C分别为2μg/mL、3μg/mL、5μg/mL,激发光波长λ为488 nm和514.5 nm,光功率P为10 mW、15 mW、20 mW等不同条件下照射,光敏剂的光漂白特性。结果表明光敏剂的光漂白时间除了与光敏剂自身类型有关,还与其浓度、入射光源的功率及波长有关。HMME在488 nm、激光功率15 mW,浓度为2μg/mL、3μg/mL、5μg/mL时光漂白时间分别为210 s、240 s、325 s。 相似文献
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Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis
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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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
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
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
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
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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
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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
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
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