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DNS法测定玉米须保健饮料中总多糖含量 总被引:1,自引:0,他引:1
目的考察供试品溶液制备的最佳条件,测定玉米须保健饮料中多糖含量。方法采用正交实验确定供试品溶液制备的最佳条件,二硝基水杨酸法显色,以葡萄糖为对照品,测定样品中总多糖的含量。结果葡萄糖质量浓度在8~56μg.mL-1范围内与吸收度呈良好的线性关系;平均回收率为101.83%,RSD=1.84%;测得的总多糖平均含量为0.850 0 mg.mL-1。结论对于成分简单的样品,采用二硝基水杨酸法测定玉米须保健饮料中总多糖含量,快速准确,稳定性好,可作为该制剂总多糖含量测定方法。 相似文献
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采用3,5—二硝基水杨酸比色法测定泌石通胶囊中檞叶多糖的含量(以无水葡萄糖计算)。结果表明,葡萄糖浓度在4—40μg/ml之间呈线性关系,方法回收率102.1%(RSD=2.2%),方法可靠,简便易行。 相似文献
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目的:建立在线水解快速测定中草药多糖的流动注射分光光度法,并应用于川芎多糖的测定。方法:于95℃水浴0.50mol·L-1盐酸在线水解多糖为还原糖,经中和后与3,5-二硝基水杨酸溶液在相同水浴条件下反应显色,排除气泡进入检测器,以540 nm吸光度定量测定多糖含量。结果:以葡萄糖表示,本法在20-150μg·mL-1浓度范围内符合线性方程△A=0.0134C-0.235,检出限为10.0μg·mL-1,RSD=2.2%(75.0μg·mL-1,n=7),采样频率为每1 h 60次,回收率为97%-104%;应用于川芎多糖测定,测得川芎中多糖含量为2.28%。结论:该法简单、快速、实用、准确度高、重现性好,用于测定川芎多糖与经典Dubois法结果一致,也适用于其它中草药多糖的快速测定。 相似文献
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达吉胶囊中纤维素酶的活力测定 总被引:1,自引:0,他引:1
目的测定达吉胶囊中纤维素酶的活力。方法以羧甲基纤维素钠为底物与酶溶液在40℃反应30 min后,用3,5-二硝基水杨酸显色法或索默季砷钼酸盐显色法测定其葡萄糖的生成量,计算酶活力。结果用3,5-二硝基水杨酸显色法与索默季砷钼酸盐显色法测定3批供试品纤维素酶活力分别为标示量的165%,108%,150%与161%,110%,148%。结论2种方法测定结果相同。3,5-二硝基水杨酸显色法测定达吉胶囊中纤维素酶的活力方法简便,精密度较好,结果准确,适用于产品的质量控制。 相似文献
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目的:建立益气散聚颗粒质量标准.方法:采用TLC法对益气散聚颗粒中黄芪、茵陈进行定性鉴别;用3,5-二硝基水杨酸(DNS)法对制剂中多糖进行含量测定;用HPLC法对制剂中盐酸小檗碱进行含量测定.结果:定性鉴别分离度较好,专属性强;样品经DNS试剂显色后于480 nm处测定吸光度,多糖含量测定线性范围为4.168~29.176 mg·L-1,r=0.999 8,平均加样回收率为97.13%,RSD为1.77%(n=6);盐酸小檗碱的含量测定线性范围为0.09~1.74 μg(r=1.000 0),平均回收率为97.06%(RSD=1.05%,n=6).结论:所建立方法准确可靠,灵敏度高,专属性强,能有效控制益气散聚颗粒的质量. 相似文献
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羧甲基壳聚糖含量的测定通常采用的方法为乙酰丙酮法,但由于市售羧甲基壳聚糖样品中氨基的的脱乙酰化程度和取代度差异,导致用乙酰丙酮法测定市售样品含量时实测值与理论值偏差较大.因此,采用测还原总糖含量的3,5-二硝基水杨酸比色法(DNS法)对羧甲基壳聚糖进行含量测定.经过方法学验证,该方法线性的平均相关系数r=0.999 5,以D-盐酸氨基葡萄糖计线性范围在200~1800μg,重复性实验RSD=1.23%,平均回收率为100.06%,RSD=2.45%,显色后吸收值在2 h内稳定.用DNS法对市售羧甲基壳聚糖样品的含量测定结果与理论含量基本相符.因此,该方法更适用于羧甲基壳聚糖的含量测定. 相似文献
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3,5-二硝基水杨酸法测定蔓菁中还原糖和总糖含量 总被引:7,自引:0,他引:7
目的建立测定晋南蔓菁还原糖和总糖含量的3,5-二硝基水杨酸比色(DNS)法。方法以葡萄糖为对照品,DNS试剂的用量为2.0 mL,90℃水浴加热6 min,于540 nm波长下测定蔓菁中还原糖和总糖含量。结果还原糖和总糖平均加样回收率分别为101.66%和96.44%,RSD分别为2.86%和1.71%(n=6);3批蔓菁中还原糖和总糖的含量分别为5.86%~6.93%和44.65%~46.50%。结论该方法简便、准确、重复性好,可用于检测蔓菁中还原糖和总糖的含量。 相似文献
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目的:建立蛭芪康胶囊的质量控制方法。方法:采用薄层色谱法对制剂中的天麻蜜环菌粉、大黄、黄芪进行定性鉴别。采用3,5-二硝基水杨酸光度法(DNS)测定制剂多糖含量,采用Folin-酚法(Lowry法)测定制剂肽含量。结果:定性鉴别检出制剂中的天麻蜜环茵粉、大黄、黄芪;DNS法测定结果,多糖在6.412—32.060μg·ml-1的范围内呈良好的线性关系(r=0.9995),平均回收率为95.86%,RSD为0.86%(n=6);Folin-酚法测定结果,肽在0.0597~0.2984mg·ml-1范围内呈良好的线性关系r=0.9990),平均回收率为100.3%,RSD为1.88%(n=6)。结论:本方法简便、准确,可作为该制剂的质控方法。 相似文献
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目的探讨测定糖基化白蛋白反应液中葡萄糖含量的适宜方法。方法对3熏5-二硝基水杨酸法、邻甲苯胺法和苯酚-硫酸法三种不同测定糖含量方法进行研究比较。结果3熏5-二硝基水杨酸法、邻甲苯胺法、苯酚-硫酸法测定糖的线性范围分别为:2.5×10-5~3.0×10-4mol/L,3.0×10-5~3.0×10-4mol/L,2.5×10-5~2.5×10-4mol/L;直线回归方程为:y=0.01780x-0.05400穴r=0.9991雪,y=0.006029x+0.004286穴r=0.9988雪,y=0.01554x-0.001905穴r=0.9994雪;摩尔吸光系数为:6.5×103L/mol·cm,2.4×102L/mol·cm,2.4×104L/mol·cm;回收率分别为:101.9%~108.0%,92.3%~109.1%,94.3%~104.5%。结论苯酚-硫酸法具有操作简便、准确、灵敏、快速、显色后颜色稳定等优点,适用于测定糖基化白蛋白样品中的糖含量。 相似文献
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Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.
Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.相似文献
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Petrikovics I McGuinn WD Sylvester D Yuzapavik P Jiang J Way JL Papahadjopoulos D Hong K Yin R Cheng TC DeFrank JJ 《Drug delivery》2000,7(2):83-89
This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine. 相似文献
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《Critical reviews in toxicology》2013,43(5-6):327-369
AbstractThe uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors. 相似文献
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Chang Min Kim Kun Ho Son Sung Hwan Kim Hyun Pyo Kim 《Archives of pharmacal research》1991,14(4):305-310
In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins
from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins. 相似文献
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Alberto García-Lled Javier Gmez-Pavn Juan Gonzlez del Castillo Teresa Hernndez-Sampelayo Mari Cruz Martín-Delgado Francisco Javier Martín Snchez Manuel Martínez-Sells Jos María Molero García Santiago Moreno Guilln Fernando Rodríguez-Artalejo Julin Ruiz-Galiana Rafael Cantn Pilar De Lucas Ramos Alejandra García-Botella Emilio Bouza 《Rev Esp Quimioter》2022,35(2):115
The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation. 相似文献
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《Expert opinion on investigational drugs》2013,22(1):79-86
Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation. 相似文献