电化学共沉积制备有机高聚物/钙磷复合陶瓷膜层--Ⅱ XPS、SIMS表征及力学性能研究

通过电化学共沉积方法制备具有生物活性的有机高聚物／钙磷陶瓷复合膜层。用XPS、SIMS等对复合膜层的化学组分进行表征，证明少量有机高聚物可能在分子层次上掺杂形成有机高聚物／羟基磷灰石复合膜层。对电沉积HAP陶瓷膜层进行微刮痕实验表明，陶瓷膜层与金属基体的结合力得到显著改善。     

钛表面纳米仿生磷灰石涂层对成骨样细胞活性的生物增强效应

目的：观察钛表面纳米仿生磷灰石涂层对成骨样细胞行为的影响，为骨科常用钛植入体的表面改性及其生物效应提供实验依据。方法: 商业用纯钛经过物理、化学和生物处理，表面生成均匀薄层仿生的纳米磷灰石涂层，将仿生涂层的钛金属板与成骨样细胞复合培养，以纯钛和只经磨砂、酸蚀处理的钛板作为对照，采用MTT法检测细胞活力和增殖变化、扫描电镜和激光共聚焦荧光显微镜观察细胞形态、RT-PCR检测碱性磷酸酶基因表达。结果: 纳米仿生磷灰石涂层比非涂层钛金属表面细胞的增殖数量明显增高，细胞的形态和分布也优于对照组；培养12 d，涂层对细胞ALP基因表达的量明显高于对照组。结论: 钛金属表面纳米仿生磷灰石涂层可以增强细胞的生物效应，提高钛植入体的骨界面早期结合，具有很好的应用前景。     

In vitro and ex vivo blood compatibility study of 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymer-coated hemodialysis hollow fibers

To identify the advantages of 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymer-coated polysulfone (PSf) hollow fibers for hemodialyzer and hemofilter minimodules with hollow fibers were made and blood compatibility was evaluated in vitro and ex vivo. Three types of hollow fibers, i.e., pure PSf (no additives), PSf alloyed with poly(1-vinyl-2-pyrrolidone) (PVPy), and PSf coated with the MPC copolymer, were processed in wet conditions. Commercially available hollow fibers (APS) were used as a control sample. The PSf hollow fibers have a condensed structure. A porous structure was observed when the PVPy was alloyed before wet processing, and no effect of the innercoated MPC copolymer on the porous structure was observed. One-tenth-sized minimodules of the conventional hemodialyzer were fabricated with 200 fibers each. The solute permeability of the hollow fibers was evaluated using 10% bovine serum in a buffer solution containing cytochrome C, which is a model protein of ₂-microglobulin. After circulation for 2.5h, the solute permeability of APS and PVPy-alloyed PSf hollow fibers decreased to 50% compared with their initial values. In contrast, the value for the hollow fibers innercoated with the MPC copolymer maintained its initial level. The inner surface of the dialysis membranes was observed with a transmission electron microscope and a layer of adsorbed protein on the PSf, APS, and PVPy-alloyed PSf hollow fibers was observed, but not on the MPC copolymer-coated fibers. Blood cell adhesion was then evaluated by circulation of whole rabbit blood without any anticoagulant ex vivo. Many adherent cells were observed on the PVPy-alloyed PSf hollow fibers; however, blood cells did not adhere or aggregate on the MPC copolymer-coated hollow fibers. From these results, we concluded that the in-situ coating of MPC copolymer on PSf hollow fibers is effective in preventing blood coagulation and maintaining the solute permeability of the fibers.     

Increased metabolism to dihydrodigoxin after intake of a microencapsulated formulation of digoxin

Summary A capsule preparation containing small, enteric-coated granules of digoxin was developed to prevent acid hydrolysis of the drug in the stomach and to diminish the variation in plasma glycoside concentration during the intervals between doses. The absorption and metabolism of tritiated digoxin after a single oral loading dose of this formulation (Formulation C) were compared to those after ingestion of a digoxin solution (Formulation S) by 8 healthy men. Drug concentrations were measured by radioimmunoassay (RIA) and liquid chromatography (LC). The percentage of the digoxin dose excreted in the urine during 72 h, as measured by RIA, was significantly lower after the capsule (20.5±2.0% vs 36.2±3.0% after S, mean±SEM) but total urinary radioactivity after the two treatments was similar (C 35.3±5.2 and S 41.2±2.6%; p>0.05). The discrepancy was mainly due to significantly greater excretion of dihydrodigoxin after the capsule ( 12.8%, range 0–28.6% of the dose) than after the digoxin solution ( 5.4%, range 0–14.5%). Dihydrodigoxin was not measured by the RIA. The recovery of hydrolysis metabolites (LC) was greater during the first 24 h after S (2.3±0.6% vs 0.9±0.3% after C; p<0.05). The peak plasma concentration of digoxin (RIA) was significantly reduced and delayed after intake of C (2.5±0.4 nmol/l at 3.8±0.3 h vs. 8.3±0.8 nmol/l at 0.9±0.1 h after S), and so was the shortening of electromechanical systole at 1.5 h, 2.5 h, and 3 h. Thus, the enteric-coated digoxin preparation delayed the absorption and reduced the hydrolysis of the glycoside, but it also carried the drawback of reducing digoxin availability, mainly because of increased metabolism to dihydrodigoxin.     

纯钛表面激光合成钙磷生物陶瓷涂层的组成与结构

目的 采用廉价的CaCO_3和CaHPO_4·2H_2O作为原料,在激光的作用下通过反应制备HA生物陶瓷涂层。方法 利用X射线衍射仪和电子探针分析仪对涂层进行相分析、组织观察和成分分析。结果CaCO_3和CaHPO_4·2H_2O按20:80的质量比混合时,在功率为600W、扫描速度为3.5mm/s的激光作用下可一步合成钙磷生物陶瓷涂层。结论 在一定实验条件下,CaCO_3和CaHPO_4·2H_2O可合成组织致密、结合状态良好的钙磷生物陶瓷涂层。     

红霉素缓释微囊的制备及其释药机理的研究

本文旨在探讨红霉素微囊的制备及体外缓释机理。以明胶等为囊材,用红霉素制成微囊,研究微囊的厚度及孔隙度对药物释放速率的影响。进行理论分析,与实验结果相符性较好。     

锐钛型TiO_2性能研究 Ⅱ.锐钛型TiO_2的光化学活性封闭及其表征

用水热法ＳｉＯ２致密包覆封闭锐钛型ＴｉＯ２表面的光化学活性点,以Ｃｒ２Ｏ２－７的还原反应考察包覆层的致密性及包覆效果。讨论了ＴｉＯ２浆液的浓度、温度、ｐＨ及保温熟化等反应条件对ＳｉＯ２致密包覆的影响。     

H级无溶剂浸渍绝缘漆制备研究

以改性二苯醚树脂为原料,合成了一种新颖不饱和聚酯型无溶剂浸渍绝缘漆。它耐高温达到Ｈ级,固化速度快,贮存周期长,挥发率低。讨论了促进剂和挥发分抑制剂对无溶剂浸渍漆性能的影响,以及促进机理和抑制机理。结果证明了促进剂可以大大缩短固化时间,挥发分抑制剂在适当配比下,能够降低苯乙烯的挥发。     

红霉素肠溶微丸制备工艺

采用挤出—滚圆技术制备红霉素微丸丸芯，并用正交设计筛选其制备工艺；以甲基丙烯酸共聚物水分散体为包衣材料，建立微丸包衣数学模型指导包衣工艺。     

基因转殖酵母菌培养液中生物素的高灵敏ELISA竞争测定法

目的　发展一种测定基因转殖酵母菌培养液中生物素的灵敏ELISA竞争测定法。方法　酶标板先用猪肺炎支原体包被 ,再依次用兔抗猪肺炎支原体抗血浆、羊抗兔IgG -生物素温育形成固态生物素 ,同溶液中的生物素 (标准液或试样 )竞争有限量的链霉亲和素 HRP。建立了在 5 0 - 2 0 0 0ng·L- 1 范围内生物素的标准曲线。结果　检测限为 83ng·L- 1 ,比文献报告的ELISA测生物素的最低测定浓度小 10 0 0倍。测定生物素浓度为 2 0 0、5 0 0、10 0 0ng·L- 1 的用空白培养液稀释的标准生物素试样的相对标准偏差分别是 2 4 87%、6 15 %、7 86 % ,平均回收率为 10 1 13%。在用本法测定野生酵母菌及其 6 3个基因转殖酵母菌培养液中的生物素时 ,发现 85 %以上的培养液试样中生物素浓度均得到不同程度扩增。结论　用猪肺炎支原体作包被蛋白 ,提高了ELISA结果的精确度和准确度 ,可供测定其它介质中生物素的参考