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目的综述浊点萃取技术(CPE)的概念、特点、原理及其在药物分析和食品安全分析等领域的最新应用,为浊点萃取技术的进一步应用提供参考。方法查阅国内外浊点萃取技术在药物分析及食品安全分析应用的期刊文献并进行归纳总结。结果浊点萃取技术是利用表面活性剂的增溶性与浊点原理达到对难溶性化合物的富集与分离的一种新兴的液-液萃取技术,与传统的提取技术(固液萃取、索氏提取等)比较有机溶剂使用量少、萃取率更高、操作方法简单。结论在血浆、中药材及食品等样品的分析中,浊点萃取技术能较好富集目标分析物。 相似文献
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以红酵母静息细胞为生物催化剂,在由两种不同浊点的表面活性剂组成的浊点系统中对3,5-二(三氟甲基)苯乙酮进行生物转化,以生产3,5-二(三氟甲基)苯乙醇.分别考察了浊点系统对细胞生长和转化过程的影响.在细胞培养阶段表面活性剂Triton X-114(TX-114)能够大大提高细胞对毒性底物的耐受能力.表面活性剂浓度5%,底物浓度6μl/ml时,浊点系统的产物浓度为5.47 mg/ml,转化率为80.5%,分别比两相系统提高91.3%和78.1%.细胞经4次循环使用,活性仍保持80%以上. 相似文献
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目的优选浊点萃取法提取青蒿中青蒿素的最佳工艺。方法采用浊点萃取法提取青蒿素,并用紫外分光光度法测定含量。用正交试验法确定表面活性剂浓度、离子强度、液固比、平衡时间等因素对提取率的影响,优选最佳提取工艺。结果采用非离子表面活性剂聚氧乙烯脂肪醇醚(Genapol-X 80),浓度为15.0%,液固比为100∶1,NaCl浓度为2.0 mol/L,在60℃下萃取40 min,可达到最高的提取率。相对于传统工艺,浊点萃取法的提取率大大提高。结论该方法稳定易行,且操作简单、绿色环保、避免高温破坏、提取率高。 相似文献
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目的 对国产与进口的四种羟丙基甲基纤维素 (HPMC)物化性质进行对比。 方法 分别对四种外观、粘度、浊点、胶凝点及游离膜的透湿性、抗张强度 ,各项性质进行测试。 结果 1外观四种HPMC均属合格产品。 2粘度 国产 (瑞泰 )三种均符合USP规定 ,而日本信越公司的产品粘度比标示值稍大。 3浊点 日本信越不及瑞泰产品准确。4胶凝点 日本信越不及瑞泰产品准确。 5自制游离膜透湿性瑞泰与日本信越产品相当。 6自制游离膜抗张强度HPMC有显著差异 ,但均达到包衣要求。 结论 国产的HPMC质量已达到了日本信越同类产品水平。 相似文献
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目的建立浊点萃取提取贯叶连翘中总黄酮的工艺。方法采用浊点萃取法进行总黄酮提取,并用紫外分光光度法测定其含量。用正交实验法确定表面活性剂质量浓度、液固比、离子强度、平衡时间等关键因素对提取率的影响,优化提取工艺。结果采用非离子表面活性剂聚氧乙烯脂肪醇醚Genapol-X 80,质量浓度为50.0g.L-1,液固比为100∶1,NaCl浓度为3.0mol.L-1,在65℃下,萃取40min,达到最高的提取率,相对于传统工艺,提取率大大提高。结论该方法稳定易行,操作简单,绿色环保,避免高温破坏,提取率高。 相似文献
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国产与进口羟丙基甲基纤维素的性质对比 总被引:3,自引:0,他引:3
目的:对国产与进口的四种痉基甲基纤维素(HPMC)物化性质进行对比,方法:分别对四种外观,粘度,浊点,胶凝点及游离膜的透湿性,抗张性质性行测试,结果1外观四种HPMC均属合格产品,2粘度国产(瑞泰)三种均符合USP规定,而日本信越公司的产品粘度比标示值稍大,3浊点:日本信越不及瑞泰产品准确,4胶凝点。日本信越不及瑞泰产品准确。5自制游离膜透显性,瑞泰与日本信越产品相当,6自制游离膜抗张强度HPMC有显著差异,但均达到包衣要求,结论:国产的HPMC质量已到日本信越同类产品水平。 相似文献
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聚山梨酯80的脂肪酸组成及其精制方法研究 总被引:2,自引:0,他引:2
目的:以聚山梨酯80的色泽与脂肪酸组成作为考察指标。探求可提高其品质的有效途径。方法:参考《欧洲药典》建立聚山梨酯80脂肪酸组成的检测方法并对市售样品进行测定。后围绕浊点萃取法、三相分离法以及基于其制备原料(油酸)纯度控制这3种方法展开聚山梨酯80的精制工艺研究。结果:当选用高纯度油酸作为聚山梨酯80制备的起始原料时.产品的脂肪酸组成可达到《欧洲药典》要求,并且聚山梨酯80经浊点萃取法和三相分离法两种方法精制后,尤其经三相分离法精制后,产品的色泽可接近无色。结论:应当选用高品质起始原料进行聚山梨酯80的制备,并配合三相分离法的使用。可实现聚山梨酯80产品外观与内在品质的共同提高。 相似文献
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目的:建立浊点萃取联合高效液相色谱法测定血浆中橙皮素的方法。方法:利用非离子型表面活性剂Triton X-114胶束水溶液萃取富集橙皮素,以甲醇-0.1%磷酸水溶液(80:20)为流动相进行洗脱,Kromasil C18为色谱柱,柱温25℃,检测波长283 nm。结果:Triton X-114浓度5%、对照品溶液加入量10 μL,调pH 5,萃取温度50℃,萃取3次,每次30 min,超声5 min,所得萃取率最高,为86.6%;橙皮素在0.34~10.80 μg·mL-1内进样量与峰面积线性关系良好,Y=94.715X+4.328 5(r=0.999 4)。结论:浊点萃取和液相色谱联用来测定血浆橙皮素,不使用有机试剂,绿色环保,简便。 相似文献
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聚醚类消泡剂与抗生素工业发酵 总被引:2,自引:0,他引:2
本文介绍了某些甘油的三羟基聚氧烯醚消泡剂如聚氧丙烯甘油、聚氧乙烯氧丙烯甘油和聚氧乙烯氧丙烯甘油二硬脂酸酯等对抗生素发酵的消泡规律。介绍了它们的消泡效力与分子中憎水基的平均分子量和亲水基的百分含量的关系。表明,憎水基的平均分子量为3000~4000,亲水基的百分含量为10~15%的消泡效力最高。 此外,还介绍了聚醚消泡剂胶束的形成与浊点,在聚醚的生产过程中颜色的产生与防止及混浊并有冻胶沉淀的原因及防止,聚醚消泡剂的毒性及在抗生素发酵中的使用方法。 相似文献
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目的:研究柠檬醛治疗胆石症、胆囊炎、胆管炎的新适应证。方法:行大鼠胆管插管手术,引流胆汁,测量胆汁流量和胆汁成分;用致石饲料致小鼠胆石形成模型,评价柠檬醛抑制胆石形成的作用;用人胆石体外试验柠檬醛的溶石作用;用常规的疼痛模型和炎症模型,观察柠檬醛的镇痛抗炎作用。结果:柠檬醛有促进胆汁分泌的作用,反复给予柠檬醛仍有显著和持续促进大鼠胆汁分泌的作用,在利胆的同时降低胆汁中的总胆固醇、胆红素、黏液的含量;将柠檬醛予小鼠灌胃给药可抑制其胆囊结石的形成,体外实验可溶解人混合型胆石,并具有镇痛抗炎的作用。结论:柠檬醛具有强而持久的促进低含量胆固醇、胆红素和黏蛋白胆汁的分泌,以及抑制胆石的形成和溶解胆石的作用,因此柠檬醛可望成为治疗胆囊炎、胆管炎、胆石症的新药,而其镇痛抗炎、广谱抗菌的作用有助于消除胆道炎症和症状。 相似文献
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甲基黄酮醇胺盐对大鼠学习记忆的促进作用与其抗氧化作用的关系 总被引:2,自引:2,他引:0
目的研究甲基黄酮醇胺盐对大鼠学习记忆的影响,分析该药影响学习记忆与其影响脑内自由基反应的关系。方法ip甲基黄酮醇胺盐5,10mg·kg-1共7d后,采用Mor-ris水迷宫测试大鼠的学习记忆能力,同时测定训练d5和休息30d后大鼠脑内过氧化脂质(LPO)含量和超氧化歧化酶(SOD)活性。结果甲基黄酮醇胺盐两种剂量均可提高大鼠获取空间定位信息能力和信息贮存能力并增强记忆保持和再现过程。用药大鼠脑内LPO含量明显低于对照组,与其记忆成绩呈正相关性。而脑内SOD活性则高于对照组,与其记忆成绩呈负相关性。结论甲基黄酮醇胺盐对大鼠的学习记忆机能具有促进作用,而它的抗氧化作用可能为其促进学习记忆的作用机制。 相似文献
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Resolution of enantiomers is very important particularly in the fields of asymmetric synthesis, mechanistic studies, geochronology, studies of structure-function relationship of proteins, pharmacology, and medicine. Various chromatographic methods have replaced the classical fractional crystallization, seeding and enzymatic procedures. Of these, t.l.c. provides a direct, simple, and inexpensive method for resolution of enantiomers of amino acids and their derivatives. Ligand exchange, ion exchange, and molecular inclusion complexation have been the basis of t.l.c. resolution of enantiomers of amino acids and their derivatives. The innovation of new plate types, and methods of development and detection have renewed interest in the direct resolution of enantiomers of amino acids, their derivatives and a variety of other compounds by t.l.c. The present report provides an overview of some of the more recent approaches to the direct t.l.c. resolution of amino acids and their derivatives together with special advantages and scope of t.l.c. 相似文献
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布渣叶水提物解热退黄作用的实验研究 总被引:4,自引:0,他引:4
目的:研究布渣叶水提物的解热、退黄作用。方法:采用干酵母复制大鼠发热模型,α-萘异硫氰酸萘脂中毒诱导小鼠黄疸模型,观察布渣叶水提物的解热、退黄作用。结果:高、中剂量的布渣叶水提物对发热模型大鼠有显著降温作用;高、中、低剂量的布渣叶水提物能显著降低黄疸模型小鼠血清中总胆红素(T-Bil)与直接胆红素(D-Bil)的含量,并能显著抑制丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)活性。结论:布渣叶水提物具有一定的解热作用,并有良好的退黄与改善肝功能的作用。 相似文献
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目的研究舒芬太尼+咪达唑仑在乳腺癌手术麻醉复苏中的应用,术后麻醉苏醒情况及拔管时血流动力学变化。方法选取ASAⅠ级,临床诊断为乳腺癌,拟行乳腺癌改良根治术患者60例,随机分为三组,每组20例,三组均采用气管内插管全身麻醉方式,以维库溴铵诱导插管,1组(F)以芬太尼+异丙酚+咪达唑仑维持麻醉,2组(S)以舒芬太尼+丙泊酚+咪达唑仑维持麻醉,3组(T)以舒芬太尼+丙泊酚+咪达唑仑维持麻醉,于术毕前10min停止丙泊酚输注,追加舒芬太尼+咪达唑仑,观察记录手术结束,取吸痰时,拔管时及拔管后MAP,HR,与基础值进行比较,记录呼患者睁眼时间,拔除气管导管时间和OAA/S评分。结果与术毕时比,F组和S组的MAP和HR在吸痰、拔管时均明显增高(P<0.05)。在睁眼时间、拔管时间两项观察指标中,各组之间差异有统计学意义,T组患者睁眼时间及拔管时间最短,S组次之,F组最慢,OAA/S评分T组评分较F组和S组明显升高(P<0.05)。结论舒芬太尼联合咪达唑仑用于乳腺癌手术患者,能保证很好的麻醉深度,术毕前10min追加舒芬太尼+咪达唑仑,拔管时心血管反应轻,术毕苏醒时间快,清醒状况良好,值得临床推广。 相似文献
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Daphne Gail Fautin 《Toxicon》2009,54(8):1054-1064
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《Expert opinion on investigational drugs》2013,22(8):1545-1558
Invasive fungal infections are important causes of morbidity and mortality in hospitalised patients. Current therapy with amphotericin B and antifungal triazoles has overlapping targets and is limited by toxicity and resistance. The echinocandin lipopeptide caspofungin is the first of a new class of antifungal compounds that inhibit the synthesis of 1,3-β-D-glucan. This homopolysaccharide is a major component of the cell wall of many pathogenic fungi and yet is absent in mammalian cells. It provides osmotic stability and is important for cell growth and cell division. In vitro, caspofungin has broad-spectrum antifungal activity against Candida and Aspergillus spp. without cross-resistance to existing agents. The compound exerts prolonged post-antifungal effects and fungicidal activity against Candida spp. and causes severe damage of Aspergillus fumigatus at the sites of hyphal growth. Animal models have demonstrated efficacy against disseminated candidiasis and disseminated and pulmonary aspergillosis, both in normal and in immunocompromised animals. Caspofungin possesses favourable pharmacokinetic properties and is not metabolised through the cytochrome P450 (CYP) enzyme system. It showed highly promising antifungal efficacy in Phase II and III clinical trials in immunocompromised patients with oesophageal candidiasis. Caspofungin was effective in patients with invasive aspergillosis intolerant or refractory to standard therapies. Based on its documented antifungal efficacy and an excellent safety profile, caspofungin has been approved recently by the US Food and Drug Administration for the treatment of invasive aspergillosis in patients who are refractory to or intolerant of other therapies (i.e., amphotericin B, lipid formulations of amphotericin B, and/or itraconazole). Phase III clinical trials in patients with candidaemia and in persistently febrile neutropenic patients requiring empirical antifungal therapy are ongoing. This paper reviews the preclinical and clinical pharmacology of caspofungin and its potential role for treatment of invasive and superficial fungal infections in patients. 相似文献
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目的:研究荜澄茄治疗胆石症、胆囊炎、胆管炎的新适应证。方法:行大鼠胆管插管手术,引流胆汁,测量胆汁流量和胆汁成分;用致石饲料致小鼠胆石形成模型,评价荜澄茄抑制胆石形成的作用;用人胆石体外试验荜澄茄的溶石作用;用常规的疼痛模型和炎症模型,观察荜澄茄的镇痛抗炎作用。结果:荜澄茄的水提物、醚提物、醇提物都有促进大鼠胆汁分泌的作用,并反复给予其提取物仍有显著和持续地促进大鼠胆汁的分泌作用;在利胆的同时降低胆汁中的总胆固醇、胆红素、黏液的含量,喂饲其生药粉末还可抑制小鼠胆囊结石的形成;体外实验其醚提物可溶解人混合型胆石;将其给小鼠灌胃有镇痛抗炎的作用。结论:荜澄茄具有促进低含量胆固醇、胆红素和黏蛋白胆汁分泌以及具有抑制胆石形成和溶解胆石的作用;因此,患胆囊炎、胆管炎和胆石症的患者可望成为草澄茄制剂治疗的新适应证,而其镇痛抗炎作用及其广谱抗菌作用将有助于消除胆道炎症和症状。 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