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Angelica Maria Gerardos Anastasia Balafouti Stergios Pispas 《Macromolecular chemistry and physics.》2023,224(17):2300109
Mixed micelles have numerous advantages while requiring little to no effort in preparation. This study aims to produce mixed micelle nanostructures from a linear triblock copolymer and a hyperbranched random copolymer, and is able to be loaded with the weakly water-soluble drugs curcumin and indomethacin. Different preparation techniques are employed to produce mixed micelles comprised of Pluronic F127 block copolymer, and hyperbranched poly[(ethylene glycol) methyl ether methacrylate-co-lauryl methacrylate], H-[P(OEGMA-co-LMA)], copolymer. Few studies have dabbled in these types of coassemblies, which provides insight into how structural differences of each copolymer can affect the formation of micelles. To determine the properties of the emerging nanostructures in aqueous environments, including their size, homogeneity, and surface charge, different physicochemical techniques are used, such as light scattering and spectroscopic methods. The results reveal that the copolymers combine, and spontaneously self-assemble into mixed micelle-like nanostructures in aqueous environments, whereas both systems of neat and drug-loaded nanostructures exhibit desirable properties such as small average micelle hydrodynamic radii and low size polydispersity indices. The nanostructures that result from the effective encapsulation of curcumin exhibit outstanding stability over 169 days. The fluorescent qualities of curcumin persist after encapsulation, making the novel nanostructures excellent candidates for bioimaging applications. 相似文献
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Data from analgesic clinical trials have characteristics such as ordered categorical longitudinal responses with repeated measures, delay of effect with respect to analgesic plasma concentration, and right-hand censoring of response due to remedication. In order to determine the concentration-effect relationship of such data, we propose convolving an empirical function for plasma concentration, in the form of broken lines which connect each pair of neighboring observations, with a monoexponential function, to generate effect site concentration Effect site concentration and time are used, simultaneously, as independent variables in the fit of the model for the logit of the probability of having a specific pain relief (PR) score at each time point pre-remedication, via maximum likelihood. Using corresponding effect site concentration, the probabilities of having specific PR scores post-remedication are predicted via the concentration-response relationship established. The overall (pre- and post-remedication) predictions and corresponding standard errors for the responses are then estimated. Inference of the PR scoring, using a posterior method, is proposed. An illustration using real data is used to demonstrate these methods. 相似文献
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目的 应用非线性混合效应模型法(NONMEM),估算癫癇患者苯妥英群体药物动力学参数,考察各因素对最大消除速率常数Vm(mg·d-1)及米氏常数Km(mg·L-1)的影响。方法 回顾性搜集56例门诊及住院癫癇患者服用苯妥英钠日剂量和血药浓度数据96对,并运行SAS程序进行计算。结果 患者的性别、年龄、体重、合并用药等对药物动力学参数均无显著性影响,Vm=(522.40±10.25)mg·d-1(513.14~630.63 mg·d-1),Km=(11.05±9.62)mg·L-1(1.90~34.83 mg·L-1)。血药浓度预测值与实测值相关性良好。结论 用非线性混合效应模型法估算癫癇患者苯妥英群体药物动力学参数方法可靠,值得推广。 相似文献
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目的 :观察中药通络助孕方对慢性炎症大鼠模型输卵管病理形态学和受孕率的影响 ,并探讨其疗效机理。方法 :用混合菌接种法制作大鼠慢性炎症动物模型 ,以不同剂量的通络助孕方和对照药妇炎康治疗后 ,观察用药前后光镜和电镜下输卵管病理形态学改变情况 ,并追踪大鼠受孕情况。结果 :通络助孕方和对照药能不同程度恢复模型大鼠输卵管病理形态学改变 ,并提高了受孕率。结论 :模型大鼠输卵管组织呈慢性炎症表现 ,混合菌接种法可以成功制作大鼠慢性炎症模型 ;通络助孕方能改善输卵管结构和功能 ,从而对大鼠炎性不孕具有很好的治疗作用 相似文献
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Abstract: There is evidence to indicate that opioid compounds with mixed μ agonist/δ antagonist properties are analgesics with low propensity to produce tolerance and physical dependence. A chimeric peptide containing the potent and selective μ agonist H‐Dmt‐D‐Arg‐Phe‐Lys‐NH2 ([Dmt1]DALDA) (Dmt = 2′,6′‐dimethyltyrosine) and the potent and selective δ antagonist H‐Tyr‐TicΨ[CH2‐NH]Cha‐Phe‐OH (TICP[Ψ]) (Cha = cyclohexylalanine), connected ‘tail‐to‐tail’ via a short linker, was synthesized using a combination of solid‐phase and solution techniques. The resulting peptide, H‐Dmt→D‐Arg→Phe→Lys‐NH‐CH2‐CH2‐NH‐Phe←Cha[NH‐CH2]ΨTic←Tyr‐H, showed the expected μ agonist/δ antagonist profile in the guinea‐pig ileum and mouse vas deferens assays. Its μ and δ receptor binding affinities were in the low nanomolar range, as determined in rat brain membrane binding assays. 相似文献
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Patients with xeroderma pigmentosum (XP) are highly sensitive to ultraviolet radiation and prone to develop multiple skin
malignancies. We report two children under 6 years of age with XP who each developed two histologically different types of
malignancies simultaneously. We conclude that it is of importance to be aware of the possibility of multiple malignancies
of different types, even in young children.
Accepted: 16 December 1996 相似文献
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