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合成了水杨酸铜络合物并分析了其组成,提纯了Tween-20,-40,-60,-80,并测定了它们在pH7.4的磷酸缓冲液中的CMC,用Cyt.c,还原法分别测定了水杨酸铜络合物在不同介质中的SOD样活性,详细研究了表面活性剂与水杨酸铜络合物协同清除O2^-的作用,观察到在胶束体系中水杨酸铜络合物的SOD样活性明显高于缓冲液体系无表面活性剂时的SOD样活性,表面活性剂本身也具有清除O2^-的功能,抗红细胞膜脂质过氧化实验也得到类似结果,这可用胶束催化解释,水杨酸铜-Tween体系可能是一种潜在的抗炎药物。 相似文献
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对Cu(Ⅱ)一姜黄素以1:1(络合物1)和1:2(络合物2)两种不同化学计量关系形成的络合物进行了清除自由基和抗氧化活性对比实验,以了解化学计量关系与结构的改变对它们抗氧化活性的影响。1)用EPR光谱分析溶于J:DMSO中的络合物1和2,结果证实这两种络合物的结构分别为扭曲的斜方型和对称的正方平面型。而前者的结构具有更高的SOD活性。2)通过细胞色素C(Fe~(2+))吸收法研究2个 相似文献
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SOD脂质体生产新工艺研究 总被引:4,自引:0,他引:4
建立了一种适于工业生产SOD脂质体的工艺,即将已有的冷冻-融化法改进为冷冻干燥法.产品为冻干态SOD脂质体,使SOD包封率由近50%提高到65%以上,渗漏也大大减少.产品水化后振荡即可重新形成脂质体.产品稳定性增强,常温下12mo分散度无明显改变,粒径多为0.66μm,适合作为化妆品添加剂.在提高包封率方面,膜材须选用氧化指数小的新制备的蛋黄卵磷脂SOD应溶于4mmol/L PBSpH 7.4中以保持其活性. 相似文献
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超氧化物歧化酶脂质体的制备及其药物动力学 总被引:3,自引:0,他引:3
采用逆相蒸发法制得稳定的 SOD 脂质体,其包封率为54.76±4.81%。研究了两种 SOD 脂质体(Ⅰ和Ⅱ)在兔体内的药物动力学,其半衰期分别为5.94±1.95h 和5.85±2.11h。小鼠给予脂质体Ⅱ后SOD 活性以脾、肺和肝组织中最高,肾、心、脑次之,胃中无规律性。 相似文献
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SOD基因的组织结构、表达与分子克隆 总被引:3,自引:0,他引:3
超氧化物歧化酶(SOD)是一种天然的含金属抗氧化酶,它具有抗衰老、抗辐射和消炎等多种疗效。SOD包括Cu/Zn-SOD、Mn-SOD和Fe-SOD三类,其中以Cu/Zn-SOD为最重要。SOD均由核内染色体上的基因编码,这类基因既有单拷贝序列,也有多基因家庭。线粒体和叶绿体内的SOD在核内合成后,再分泌到细胞器中。多数SOD基因的表达都具有组织特异性,并受许多环境因素的诱导,有关的分子机理正在研究中,并且正在尝试SOD基因的分子克隆以及重组SOD基因在培养细胞和转基因植物中的表达。 相似文献
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目的 优化超氧化物岐化酶(SOD)脂质体的制备工艺,并考察SOD脂质体和SOD溶液在小鼠体内组织的分布.方法 采用逆相蒸发法和正交试验优化工艺制备SOD脂质体;以邻苯三酚自氧化法和脂质过氧化物法确定药物在小鼠体内组织的分布.结果 SOD脂质体的各质量评价结果良好.与SOD溶液相比,前者可提高各组织中SOD的含量,并降低脂质过氧化物水平,以血、脑、肾等最为显著.注射SOD脂质体小鼠的各组织中SOD增量最高可达102.9%,脂质过氧化物含量最低降至25.0%.结论 所得SOD脂质体有较高的包封率和稳定性,在小鼠体内具有明显的缓释和降低脂质过氧化物含量的效果. 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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《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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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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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