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排序方式: 共有355条查询结果,搜索用时 62 毫秒
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StudiesonHepatocyte┐TargetingMagneticResonanceImagingMacromolecularContrastMedia*FUYan-junandZHUORen-xi**(DepartmentofChemist... 相似文献
83.
Shao Ning WANG Ying Kun QIU Hui XU Yi Hui DENG Da Wei CHEN 《中国化学快报》2006,17(2):173-176
Mammalian hepatocytes (parenchymal cells) exclusively possess large number ofasialoglycoprotein receptors (ASGPr), which can recognize terminal D-galactose orN-acetylgalactosamine residues. Lactobionic acid 1, bearing a galactosyl group, isusually used as… 相似文献
84.
The -potential of copolymer particles of acrylic amide, acrylic acid, acrylic butyl ester, and styrene were measured in different electrolyte solutions. In an isotonic solution of sodium chloride, they vary with the content of acrylic acid between –36 mV and –49 mV. In the presence of 21-electrolytes, the -potential could be correlated with the logarithm of the electrolyte concentration. The 21-electrolytes predominantly determine the -potential of the particles not only in the solutions of these electrolytes, but also in mixed electrolyte solutions. In the presence of human serum, the electrophoretic mobility increases with increasing acrylic acid content of the polymer. 相似文献
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A previous study has shown that retention of magnetic particles at a model airway surface requires prohibitively strong magnetic fields. As mucus viscoelasticity is the most significant factor contributing to clearance of magnetic particles from the airway surface, mucolytics are considered in this study to reduce mucus viscoelasticity and enable particle retention with moderate strength magnetic fields. The excised frog palate model was used to simulate the airway surface. Two mucolytics, N-acetylcysteine (NAC) and dextran sulfate (DS) were tested. NAC was found to enable retention at moderate field values (148 mT with a gradient of 10.2 T/m), whereas DS was found to be effective only for sufficiently large particle concentrations at the airway surface. The possible mechanisms for the observed behavior with different mucolytics are also discussed based on aggregate formation and the loading of cilia. 相似文献
87.
具有癌细胞靶向性的荧光纳米探针在生物分析、生物医学和临床诊断等领域有着重要的应用前景。 本文基于碳量子点的低毒性、低成本、环境友好、制备方法简单及高发光特性等优点,采用水热法合成了表面富含氨基的荧光碳量子点(CDs),进一步通过1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐(EDC)缩合的方法,将叶酸(FA)分子中的羧基与其共价连接,从而得到叶酸共价修饰的碳量子点复合材料(FA-CDs)。 通过将该复合材料分别与海拉(Hela)和小鼠胚胎成纤维(NIH-3T3)细胞共培养,发现该复合材料能够特异性识别并标记癌细胞,且制备的该复合材料具有低毒性和高发光性等优点。 该工作对癌细胞的早期诊断具有重要意义。 相似文献
88.
Yanhui Sun Aiyan Zhan Shuang Zhou Xiao Kuang Hongyan Shen Hongzhuo Liu Youjun Xu 《中国化学快报》2019,30(7):1435-1439
A novel mitochdrial-targeting tetrapeptide, RF-2(D-Arg-Dmt-Arg-Phe-NH2) had been developed, which showed controlled toxicity and excellent protection against gentamicin-induced hair cell damage, and more importantly, exhibited superior guidance towards mitochondrion achieved by its modified nanoparticles. 相似文献
89.
Bethany Almeida Okhil K. Nag Katherine E. Rogers James B. Delehanty 《Molecules (Basel, Switzerland)》2020,25(23)
In nanoparticle (NP)-mediated drug delivery, liposomes are the most widely used drug carrier, and the only NP system currently approved by the FDA for clinical use, owing to their advantageous physicochemical properties and excellent biocompatibility. Recent advances in liposome technology have been focused on bioconjugation strategies to improve drug loading, targeting, and overall efficacy. In this review, we highlight recent literature reports (covering the last five years) focused on bioconjugation strategies for the enhancement of liposome-mediated drug delivery. These advances encompass the improvement of drug loading/incorporation and the specific targeting of liposomes to the site of interest/drug action. We conclude with a section highlighting the role of bioconjugation strategies in liposome systems currently being evaluated for clinical use and a forward-looking discussion of the field of liposomal drug delivery. 相似文献
90.
采用热还原沉淀法制备了一系列Co~(2+)/Dy~(3+)掺杂的纳米立方MxFe3-xO4磁性颗粒.利用X射线衍射仪、透射电子显微镜和振动样品磁强计研究了不同含量掺杂离子对MxFe3-xO4晶体结构、形貌及磁性的影响.研究发现,掺杂未改变母体的对称性,但母体形貌逐渐从立方体向球体过渡;Co~(2+)和Dy~(3+)的掺杂对于铁氧体磁学性质的影响明显不同,当Co~(2+)实际掺杂量为0.44和Dy~(3+)实际掺杂量为0.05时,MxFe3-xO4立方磁性粒子的饱和磁化强度(Ms)达到最大值,分别为76.65和70.21 A·m2·kg-1.与超顺磁性Fe_3O_4球体相比,高磁性掺杂Fe_3O_4立方体在体外模拟磁流体磁靶向定位实验中显示出较高的滞留率. 相似文献