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目的研究从魟鱼肝脏中提取、精炼、纯化鱼油的方法,并测定其EPA和DHA含量。方法采用正己烷超声提取,磷酸脱胶,氢氧化钠脱酸,活性碳脱色,旋转蒸发脱臭和脱腥,盐析法提取总脂肪酸,尿素乙醇包合获得高纯度的不饱和脂肪酸,然后用HPLC测定EPA和DHA含量。结果精炼后的鱼油为浅黄色澄清透明,有略淡的鱼腥味,其各项指标均达到了SC/T3502-2000标准的一级要求;纯化后的鱼油质量为肝脏质量的16.1%,其中EPA和DHA的含量分别为19.54%和57.62%。结论魟鱼肝脏中提取、精炼、纯化鱼油的方法可行,检测方法可靠。 相似文献
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目的 研究从魟鱼肝脏中提取、精炼、纯化鱼油的方法,并测定其EPA和DHA含量。方法 采用正己烷超声提取,磷酸脱胶,氢氧化钠脱酸,活性碳脱色,旋转蒸发脱臭和脱腥,盐析法提取总脂肪酸,尿素乙醇包合获得高纯度的不饱和脂肪酸,然后用HPLC测定 EPA和DHA含量。结果 精炼后的鱼油为浅黄色澄清透明,有略淡的鱼腥味,其各项指标均达到了SC/T3502-2000标准的一级要求;纯化后的鱼油质量为肝脏质量的16.1%,其中EPA和DHA的含量分别为19.54%和57.62%。结论 魟鱼肝脏中提取、精炼、纯化鱼油的方法可行,检测方法可靠。 相似文献
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蚕蛹油中α-亚麻酸的尿素包合法纯化与含量测定 总被引:1,自引:0,他引:1
目的纯化蚕蛹油中α-亚麻酸并建立含量测定方法。方法采用尿素包合法富集α-亚麻酸并用均匀设计法优化筛选其最佳工艺条件,气相色谱法测定蚕蛹油中α-亚麻酸的含量。结果尿素包合后,蚕蛹油中α-亚麻酸的含量由35.2%提高到74.7%;α-亚麻酸浓度在0.125~4.000 mg/mL范围内线性关系良好(r=0.999 9),平均回收率为99.8%。结论尿素包合法能有效提高蚕蛹油中α-亚麻酸含量;气相色谱法用于测定蚕蛹油中α-亚麻酸的含量,方法简便、准确、可靠,可用于α-亚麻酸及其制剂的质量控制。 相似文献
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目的 建立海带多酚的提取及纯化工艺。方法 以乙醇浓度、提取时间、提取温度和料液比进行单因素试验,并在单因素试验基础上采用4因素3水平进行正交试验优化提取工艺,同时采用树脂进行纯化工艺优化。结果 确定最佳提取工艺为:采用85%乙醇为溶剂,以料液比1︰65,在65 ℃下搅拌提取1 h。在提取海带粗多酚后采用大孔吸附树脂进行分离纯化研究,筛选出最佳的大孔吸附树脂SZ-3,优化最佳层析条件,获得高纯度海带多酚(80%)。结论 本方法简便可行,可用于海带多酚的提取与纯化。 相似文献
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河豚鱼肝油中EPA、DHA的纯化与含量测定 总被引:1,自引:0,他引:1
目的:研究河豚鱼肝油中二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)的纯化方法,并建立EPA和DHA的含量测定方法。方法:河豚鱼肝油经精炼、盐析、低温-钾盐乙醇法和尿素包合法相结合纯化得不饱和脂肪酸;不饱和脂肪酸经甲脂化后,采用气相色谱法测定EPA和DHA的含量。结果:河豚鱼肝油经纯化可获得高纯度的不饱和脂肪酸;EPA和DHA的含量分别为0.2619g·g-1和0.4527g·g-1。EPA甲酯和DHA甲酯标准品浓度均在0.05~0.25mg·mL-1范围内同其与内标的峰面积比值呈良好的线性关系(r分别为0.9997、0.9998)。结论:河豚鱼肝油中EPA和DHA的纯化方法可行;检测方法操作简单、结果准确、重复性良好,是一种可行的含量测定方法。 相似文献
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蚕蛹油中α-亚麻酸的纯化与气相色谱含量测定方法研究 总被引:1,自引:0,他引:1
目的:纯化蚕蛹油中α-亚麻酸并建立含量测定方法。方法:采用尿素包合法富集α-亚麻酸并用均匀设计法优化筛选其最佳工艺条件,气相色谱内标法测定蚕蛹油中α-亚麻酸的含量。结果:尿素包合后,蚕蛹油中α-亚麻酸的含量由31.0%提高到58.3%;α-亚麻酸浓度在0.125~4.000mg·mL~(-1)范围内线性关系良好(r=0.9999),平均回收率为99.8%。结论:尿素包合法能有效提高蚕蛹油中α-亚麻酸含量;气相色谱内标法用于测定蚕蛹油中α-亚麻酸的含量,方法简便、准确、可靠,可用于α-亚麻酸及其制剂的质量控制。 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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Elaine S. Coimbra Rafael Carvalhaes Richard M. Grazul Patricia A. Machado Marcos V. N. De Souza Adilson D. Da Silva 《Chemical biology & drug design》2010,75(6):628-631
We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells. 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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Zusammenfassung Mittels Gaschromatographie und Dünschichtchromatographie wiesen die Autoren 11 Substanzen nach, welche durch Injektion oder nach Verabreichung per os in die Kniegelenksynovialflüssigkeit eindrangen. In ihrer Aufstellung konnten sie eine direkte Beziehung zwischen Struktur sowie chemischphysikalischen Eigenschaften der Substanz und ihrer Fähigkeit, aus dem Blut in die Kniegelenksynovialflüssigkeit einzudringen, nicht nachweisen, außer der Tatsache, daß Substanzen mit starker Affinität zu Eiweißstoffen erst in höheren Dosen nachweisbar waren. 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
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Lung disease and PKCs 总被引:1,自引:0,他引:1
The lung offers a rich opportunity for development of therapeutic strategies focused on isozymes of protein kinase C (PKCs). PKCs are important in many cellular responses in the lung, and existing therapies for pulmonary disorders are inadequate. The lung poses unique challenges as it interfaces with air and blood, contains a pulmonary and systemic circulation, and consists of many cell types. Key structures are bronchial and pulmonary vessels, branching airways, and distal air sacs defined by alveolar walls containing capillaries and interstitial space. The cellular composition of each vessel, airway, and alveolar wall is heterogeneous. Injurious environmental stimuli signal through PKCs and cause a variety of disorders. Edema formation and pulmonary hypertension (PHTN) result from derangements in endothelial, smooth muscle (SM), and/or adventitial fibroblast cell phenotype. Asthma, chronic obstructive pulmonary disease (COPD), and lung cancer are characterized by distinctive pathological changes in airway epithelial, SM, and mucous-generating cells. Acute and chronic pneumonitis and fibrosis occur in the alveolar space and interstitium with type 2 pneumocytes and interstitial fibroblasts/myofibroblasts playing a prominent role. At each site, inflammatory, immune, and vascular progenitor cells contribute to the injury and repair process. Many strategies have been used to investigate PKCs in lung injury. Isolated organ preparations and whole animal studies are powerful approaches especially when genetically engineered mice are used. More analysis of PKC isozymes in normal and diseased human lung tissue and cells is needed to complement this work. Since opposing or counter-regulatory effects of selected PKCs in the same cell or tissue have been found, it may be desirable to target more than one PKC isozyme and potentially in different directions. Because multiple signaling pathways contribute to the key cellular responses important in lung biology, therapeutic strategies targeting PKCs may be more effective if combined with inhibitors of other pathways for additive or synergistic effect. Mechanisms that regulate PKC activity, including phosphorylation and interaction with isozyme-specific binding proteins, are also potential therapeutic targets. Key isotypes of PKC involved in lung pathophysiology are summarized and current and evolving therapeutic approaches to target them are identified. 相似文献