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81.
In vivo and in vitro metabolism of aspirin eugenol ester in dog by liquid chromatography tandem mass spectrometry 下载免费PDF全文
Youming Shen Xiwang Liu Yajun Yang Jianyong Li Ning Ma Bing Li 《Biomedical chromatography : BMC》2015,29(1):129-137
Aspirin eugenol ester (AEE) is a promising drug candidate for treatment of inflammation, pain and fever and prevention of cardiovascular diseases with fewer side effects than its precursor, aspirin. Investigation into its metabolic process in target animal species will help to illustrate its mechanism of action and to establish its residual mark compound to formulate its dosage. Six beagle dogs were orally given a dose of 20 mg kg?1 of AEE and one dog was used to prepare blank liver microsomes. Their liver microsomes were prepared for in vitro study and their plasma and urine were collected for in vivo metabolic analysis using liquid chromatography tandem mass spectrometry. In this study we identified 10 metabolites, M1, M2, M3, M4, M5 in phase I and M6, M7, M8, M9, M10 in phase II. Based on the metabolites of AEE, the pathways of AEE metabolism in dog were demonstrated. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
82.
博士生在课堂上提出问题:"自然基矢量能否求协变导数?"。本文以此问题为引子,引入公理化思想,定义了广义分量和广义协变导数概念,并以新概念为基础,将经典协变性发展为广义协变性,将经典协变微分学发展为广义协变微分学。论文综述了探索中遇到的困难以及突破的途径,展示了广义协变导数概念的抽象过程和广义协变性思想的演进过程。 相似文献
83.
The Ramanujan Journal - One encounters iterated elliptic integrals in the study of Hall effect devices, as a result of conformal mappings of Schwarz–Christoffel type. Some of these double... 相似文献
84.
In the previous studies, the phenomenon that the interstitial fluid(ISF) can flow along tunica adventitia of the arteries and veins in both human and animal bodies was reported. On the basis of these studies, this paper aims to:(i) summarize the basic properties of the ISF flows in the walls of arteries and veins,(ii) combine the basic properties with axiomaticism and abstract the axiom for ISF flows, and(iii) propose three fundamental laws of the ISF flow,(i.e., the existence law, the homotropic law and the reverse law). The three laws provide solid theoretical basement for exploring the kinematic patterns of interstitial fluid flow in the cardiovascular system. 相似文献
85.
Liu Xiangxiang Mu Yajun Zhao Jing Zhang Zhong Shao Pengpeng Liu Guocheng Li Xiaohui Chen Yongqiang 《Transition Metal Chemistry》2021,46(8):613-621
Transition Metal Chemistry - To investigate the effect of the sites of S-atoms in thiophene carboxylates on the structures of coordination polymers, two thiophene-mono-carboxylic acids... 相似文献
86.
Hao Shao Xuebin Zhang Fanyan Chen Shasha Liu Yi Ji Yajun Zhu Yi Feng 《Applied Physics A: Materials Science & Processing》2012,109(4):961-965
In this paper, smooth α-Fe2O3 nanotubes have been successfully synthesized by electrospinning of ferric nitrate–polyvinyl alcohol solution followed by calcination in air. The morphologies and structures of the samples were characterized by transmission electron microscopy, scanning electron microscopy and X-ray diffraction. The catalytic properties were studied by differential thermal analysis and thermogravimetric analysis. The results indicated that the as-prepared α-Fe2O3 nanotubes showed a continuous morphology and an extremely high degree of crystallization. The average inner and outer diameters of the obtained α-Fe2O3 nanotubes were about 60 nm and 100 nm, respectively. The obtained α-Fe2O3 nanotubes were able to lower the temperature of the high-temperature thermal decomposition of ammonium perchlorate, while they had little effect on the crystallographic phase transformation and the low-temperature thermal decomposition. 相似文献
87.
同族元素及化合物的性能与周期序数的关系 总被引:1,自引:0,他引:1
本文用周期序数的倒数 1 / n代表同族原子大体结构效应的因素 ,用公式 :P=a b/ n将同族元素及化合物的二十多种性能 (P)对 1 / n进行线性回归 ,得到良好结果。 相似文献
88.
Temperature and Redox Dual‐Responsive Biodegradable Nanogels for Optimizing Antitumor Drug Delivery 下载免费PDF全文
Yefei Tian Yang Wang Shun Shen Xinguo Jiang Yajun Wang Wuli Yang 《Particle & Particle Systems Characterization》2015,32(12):1092-1101
The strategy to efficiently deliver antitumor drugs via nanocarriers to targeted tumor sites and achieve controllable drug release is attracting great research interest in cancer therapy. In this study, a novel type of disulfide‐bonded poly(vinylcaprolactam) (PVCL)‐based nanogels with tunable volume phase transition temperature and excellent redox‐labile property are prepared. The nanogels are hydrophilic and swell at 37 °C, whereas under hyperthermia (e.g., 41 °C), the nanogels undergo sharp hydrophilic/hydrophobic transition and volume collapse, which enhances the cellular uptake and drug release. The incorporation of disulfide bond linkers endows the nanogels with an excellent disassembly property in reducing environments, which greatly facilitates drug release in tumor cells. Nanogels loaded with doxorubicin (DOX) (DOX‐NGs) (DOX‐NGs) are stable in physiological conditions with low drug leakage (15% in 48 h), while burst release of DOX (92% in 12 h) can be achieved in the presence of 10 × 10?3 m glutathione and under hyperthermia. The DOX‐NGs possess improved cell killing efficiency under hyperthermia (IC50 decreased from 1.58 μg mL?1 under normothermia to 0.5 μg mL?1). Further, the DOX‐NGs show a pronounced tumor inhibition rate of 46.6% compared with free DOX, demonstrating that this new dual‐responsive nanogels have great potential as drug delivery carriers for cancer therapy in vivo. 相似文献
89.
A QM/MM Study on the Initiation Reaction of Firefly Bioluminescence—Enzymatic Oxidation of Luciferin
Among all bioluminescent organisms, the firefly is the most famous, with a high luminescent efficiency of 41%, which is widely used in the fields of biotechnology, biomedicine and so on. The entire bioluminescence (BL) process involves a series of complicated in-vivo chemical reactions. The BL is initiated by the enzymatic oxidation of luciferin (LH2). However, the mechanism of the efficient spin-forbidden oxygenation is far from being totally understood. Via MD simulation and QM/MM calculations, this article describes the complete process of oxygenation in real protein. The oxygenation of luciferin is initiated by a single electron transfer from the trivalent anionic LH2 (L3−) to O2 to form 1[L•2−…O2•−]; the entire reaction is carried out along the ground-state potential energy surface to produce the dioxetanone (FDO−) via three transition states and two intermediates. The low energy barriers of the oxygenation reaction and biradical annihilation involved in the reaction explain this spin-forbidden reaction with high efficiency. This study is helpful for understanding the BL initiation of fireflies and the other oxygen-dependent bioluminescent organisms. 相似文献
90.
Celery was found to provoke human allergenic response in some countries. Labeling of celery ingredients was required by the European Union, and the threshold set at 10 mg/kg (0.001%). In our study, a celery mannitol transporter (Mat3) gene-based detection method was established by means of SYBR Green real-time PCR technique. No cross-reactivity was found between celery and the other food materials. Absolute detection limit (LODa), relative detection limit (LODr), and practical detection limit (LODp) of the method were determined through experiments on pure celery DNA, DNA mix, and spiked food samples. The method was able to detect 0.001% raw food sample and 0.01% heated food sample. The utility of the method was confirmed by the investigation of 13 commercial foods. 相似文献