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61.
62.
查阅大量相关文献,对近期矿物药的化学成分及药理研究概况进行综述。矿物药主要为一些天然产无机化合物晶体及其单质,不同的炮制方法往往影响其某些化学成分的含量及药效。此类药具有:抑茵、抗炎、抗肿瘤等多种药理活性。 相似文献
63.
Diez-Torrubia A Cabrera S Lambeir AM Balzarini J Camarasa MJ Velázquez S 《ChemMedChem》2012,7(4):618-628
We previously described a novel prodrug approach in which a di- or tetrapeptide moiety is linked to a wide variety of amine-containing drugs through an amide bond, which is specifically cleaved by dipeptidyl peptidase IV (DPPIV/CD26) activity. Herein we report the application of this prodrug approach to a variety of hydroxy-containing drugs (primary, secondary, tertiary, or aromatic hydroxy groups). We designed and studied tripartite prodrugs containing a dipeptide moiety (cleavable by DPPIV/CD26) and a valine as a hetero-bifunctional connector to link the dipeptide to the hydroxy group of the drug through a metabolically labile ester bond. The hydroxy-containing prodrugs showed various susceptibilities to hydrolysis by DPPIV/CD26 and serum, depending on the nature of the compound. Prodrugs of compounds containing a primary hydroxy group (as in didanosine) or a hydroxy moiety on an aromatic entity (as in acetaminophen) were most efficiently converted. In contrast, a tertiary hydroxy group was much less susceptible to conversion into its parent drug by DPPIV/CD26 or serum. A number of the prodrugs showed remarkable increases in water solubility relative to their parent drugs. 相似文献
64.
随着药物的普遍使用,研究药物与人血清白蛋白的作用机理不仅可了解药物的运输、代谢过程;而且对临床用药、药物设计、新药开发具有重要指导意义。文章综述了药物小分子与人血清白蛋白相互作用的研究手段。 相似文献
65.
66.
Preparation and evaluation of chitosan/β‐cyclodextrin magnetic nanoparticles as a photodegradable and hydrophobic drug delivery carrier 下载免费PDF全文
In this study, novel tumor targeting nanocarriers comprised of chitosan (CS)/β‐cyclodextrin (β‐CD) magnetic nanoparticles were prepared to improve the photodegradable stability and bioavailability of hydrophobic drug. Resveratrol (Res) with photodegradable and hydrophobic properties was selected as a model drug. The photodegradation rate of Res in Fe3O4 nanoparticles solution was 7.8 times lower than that in the ethanol solution. In addition, the value of the saturation magnetization of CS/β‐CD nanoparticles was found to be 19.56 emu/g with characteristic of superparamagnetism. Approximately 90% Res was entrapped into the CS/β‐CD magnetic nanoparticles with the size distribution ranging from 200 to 359 nm, and the nanoparticles were spherical in shape with high zeta potentials. Furthermore, the formation of CS/β‐CD nanoparticles showed a sustained release in vitro. These results indicated that the obtained CS/β‐CD magnetic nanoparticles were a promising magnetic targeting carrier for photodegradable and hydrophobic drugs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45076. 相似文献
67.
腐植酸及其钠盐在畜牧业中的应用 总被引:3,自引:0,他引:3
简述了腐植酸和腐植酸钠在饲料添加剂和兽药中的作用、机理和应用,表明腐植酸及其盐类在促进饲料成分的活化吸收,治疗各种炎症、外伤和促进创伤愈合等方面具有显著效果。腐植酸类物质具有资源丰富、无毒副作用、绿色环保、价格低廉等特点,在畜牧业中的应用和发展潜力很大。 相似文献
68.
综述了抗结核固定剂量复合剂分析方法的研究进展。根据已报道的抗结核固定剂量复合剂的分析方法的相关文献,分析检测方法的优缺点。通过分析检测方法,提出建议,为抗结核固定剂量复合剂的分析方法的开发提供参考依据。 相似文献
69.
The cytochrome P540 (CYP) superfamily currently includes about 9000 proteins forming more than 800 families. The enzymes catalyze monooxygenation of a vast array of compounds and play essentially two roles. They provide biodefense (detoxification of xenobiotics, antibiotic production) and participate in biosynthesis of important endogenous molecules, particularly steroids. Based on these two roles, sterol 14/*alpha*/-demethylases (CYP51) belong to the second group of P450s. The CYP51 family, however, is very special as its members preserve strict functional conservation in enzyme activity in all biological kingdoms. At amino acid identity across the kingdoms as low as 25-30%, they all catalyze essentially the same three-step reaction of oxidative removal of the 14/*alpha*/-methyl group from the lanostane frame. This reaction is the required step in sterol biosynthesis of pathogenic microbes. We have shown that specific inhibition of protozoan CYP51 can potentially provide treatment for human trypanosomiases. Three sets of CYP51 inhibitors tested in vitro and in trypanosomal cells in this study include azoles [best results being 50% cell growth inhibition at <1 and at 1.3 muM for Trypanosoma cruzi (TC) and Trypanosoma brucei (TB), respectively], non-azole compounds (50% TC cell growth inhibition at 5 microM) and substrate analogs of the 14/*alpha*/-demethylase reaction. 32-Methylene cyclopropyl lanost-7-enol exhibited selectivity toward TC with 50% cell growth inhibition at 3 microM. 相似文献
70.
Broad‐spectrum antibiotics with heterocyclic side chains strongly inhibit peroxidase‐catalyzed iodination in the presence of metallo‐β‐lactamase. This suggests that antibiotic resistance due to hydrolysis of the β‐lactam ring in antibiotics would have negative effects on thyroid activity.