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61.
Hui Huang Yabin Dai Yuefen Zhang Yongning Li Huazhen Ye Dan Guo Qiaomei Lu Xiaohua Cai 《Journal of separation science》2023,46(14):2201010
Analytical screening and validation systems based on a combination of cell membrane chromatography and two-dimensional chromatography-tandem mass spectrometry are incapable of providing prepared samples containing the active ingredients found in traditional Chinese medicine; therefore, these samples cannot be directly used in subsequent studies. In this study, a semi-preparative cell membrane chromatography column was developed using a hydrogel-modified carrier and human umbilical vein endothelial cells to optimize prepared conditions, such as hydrogel polymerization, cell fragmentation, and cell membrane volume. This increased the binding ratio of membrane protein and carrier to 15.79 mg/g. The column was systematically evaluated using multitarget tyrosine kinase inhibitors that displayed good specificity and reproducibility. Subsequently, using the column coupled with a semi-preparative high-performance liquid chromatography-offline-high-performance liquid chromatography-mass spectrometry system, 15 active ingredients were screened and purified from Indigo naturalis, and five main components were identified: l -lysine, oxyresveratrol, tryptanthrin, isorhamnetin, and indirubin. Furthermore, the pharmacological effects of the ingredients were confirmed using cell proliferation and apoptosis assays. Results revealed potent proliferation-inhibiting and apoptosis-promoting abilities on human chronic myelogenous leukemic cells and human promyelocytic leukemic cells (p < 0.001). Overall, the system presented screening and purification functions that could be used to prepare I. naturalis samples acting on the epidermal growth factor receptor and vascular endothelial cell growth factor. 相似文献
62.
Rongbiao Tang Fuhua Yan Guo-Yuan Yang Ke-Min Chen 《Journal of synchrotron radiation》2017,24(6):1260-1264
Preoperative portal vein embolization (PVE) is employed clinically to avoid postoperative liver insufficiency. Animal models are usually used to study PVE in terms of mechanisms and pathophysiological changes. PVE is formerly monitored by conventional absorption contrast imaging (ACI) with iodine contrast agent. However, the side effects induced by iodine can give rise to animal damage and death. In this study, the feasibility of using phase contrast imaging (PCI) to show PVE using homemade CO2 microbubbles in living rats has been investigated. CO2 gas was first formed from the reaction between citric acid and sodium bicarbonate. The CO2 gas was then encapsulated by egg white to fabricate CO2 microbubbles. ACI and PCI of CO2 microbubbles were performed and compared in vitro. An additional increase in contrast was detected in PCI. PCI showed that CO2 microbubbles gradually dissolved over time, and the remaining CO2 microbubbles became larger. By PCI, the CO2 microbubbles were found to have certain stability, suggesting their potential use as embolic agents. CO2 microbubbles were injected into the main portal trunk to perform PVE in living rats. PCI exploited the differences in the refractive index and facilitated clear visualization of the PVE after the injection of CO2 microbubbles. Findings from this study suggest that homemade CO2 microbubbles‐based PCI is a novel modality for preclinical PVE research. 相似文献
63.
Impact of NIR wavelength lighting in image acquisition on finger vein biometric system effectiveness
Finger vein biometric systems become increasingly more popular because they offer higher security comparing to other authentication solutions with respect to positive persons experience. Those systems operate on near infrared light (NIR) in wavelength range from around 700 to 1000 nm, however dedicated research to determine impact of NIR lighting on biometric system effectiveness has not been conducted and presented in the literature ever before. In this paper the study of correlation between wavelengths in NIR spectra and effectiveness of person identification in a biometric system is presented. To achieve that goal, a new model of image acquisition system allowing change of light wavelengths has been created and NIR finger vein dataset containing 11 556 images was established. Furthermore, this model was used to perform experimental work and proof that some NIR wavelengths better suit for vein patterns acquisition, allowing to increase the recognition effectiveness of finger vein biometric systems. 相似文献
64.
深静脉血栓(DVT)是一种血栓栓塞性疾病,具有高发病率、高死亡率和高后遗症3大特点。采用左股静脉不完全结扎加高渗盐水刺激建立DVT大鼠模型,使用超高效液相色谱-静电场轨道阱高分辨质谱(UHPLC-Orbitrap HRMS)检测假手术组与DVT模型组的血浆代谢谱,用主成分分析(PCA)及正交偏最小二乘-判别分析(OPLS-DA)对代谢组数据进行多元统计分析,观察两组间的代谢表型差异,将多变量模型分析中的变量重要性值(VIP>1)以及代谢物在模型组中的变化倍数(FC≤0.5或FC≥2,且P<0.05)作为差异代谢物筛选条件。最终在DVT模型组与假手术组间筛选得到27种差异代谢物,这些代谢物反映了DVT大鼠的代谢紊乱情况。具体表现为与假手术组相比,DVT模型组中三甲基胺氮氧化物(TMAO)、维生素K、鹅去氧胆酸、牛磺酸、1-甲基烟酰胺、7-酮胆固醇、反式十六烷基-2-烯醇肉碱、乙烯基乙酰甘氨酸、丙酰脯氨酸、咪唑乙酸、咪唑乙酸核糖苷、1,3,7-三甲基尿酸、1-丁胺、2-羟基异丙酸、吡哆醛、5α-四氢皮质酮、苯乳酸的水平显著升高;而3-脱氢肉碱、磷脂酰胆碱22∶6/20∶2(PC... 相似文献
65.
浅埋偏压隧道出口变形机理及稳定性分析 总被引:2,自引:0,他引:2
以皖南某公路浅埋偏压隧道出口段高边坡为研究对象,提出了"零开挖进洞"的施工方案,并结合洞口的工程地质条件,采取必要的加固措施。通过对该边坡现场工程地质条件的系统调查,首先对边坡的岩体结构类型及其成因机制、结构面与坡面组合特征进行细致研究,在此基础上通过FLAC3D数值模拟,结合工程地质条件分析,对其变形破坏机制进行深入探讨。研究结果表明,边坡的变形首先以隧道内侧存在的软弱岩体(挤压错动带、断层)的不均匀压缩为先导,进而引起上部岩体产生由NE向陡缓结构面构成的阶梯状滑动,这将会使隧道构筑物及隧道外壁承受较大的压应力,当压应力超过隧道构筑物及外壁的极限强度时将产生破坏,从而诱发上部岩体产生更大规模的地质灾害。基于此,隧道进洞开挖前首先应对上部岩体进行加固处理,避免隧道构筑物及隧道外壁产生应力集中现象。 相似文献
66.
67.
细胞相容性聚氨酯的合成及其细胞相容性研究 总被引:6,自引:0,他引:6
在紫外光和过氧化氢的共同作用下,过氧化氢基团被引人到聚氨酯膜(PU)表面.将丙烯酸羟乙酯(HEA)吸附于氧化后的PU膜表面,在紫外光下实现了膜表面的接枝,并考察了接枝膜的表面性能.人体脐带静脉内皮细胞粘附和生长的研究表明,HEA接枝后的PU表面细胞粘附率显著提高,细胞的生长速率加快,增值率提高. 相似文献
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70.
A novel series of[(1Z)-1-(2,2-disubstituted-5-pyridin-4-yl-1,3,4-oxadiazol-3(2H)-yl) ethylidene] (PSMB1–PSMB15) were synthesized as title compounds. The synthesis route included the cyclization of carbonyl hydrazone in the presence of excess of acetic anhydride and subsequent condensation with various aromatic amines. All the title compounds were characterized by IR, 1H NMR, MS and elemental analysis. They were screened for their goat pulmonary vein relaxant activity. Compound PSMB9 was found the most active derivative exhibiting 83.33% relaxation. Isosorbide dinitrate was used as the standard drug for goat pulmonary vein relaxant activity. 相似文献