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31.
交泰丸最优配伍比例研究   总被引:1,自引:0,他引:1  
目的:探讨交泰丸组方药物黄连与肉桂的最优配伍比例及不同比例时镇静催眠的有效成分变化。方法:选择SD大鼠60只,随机分为正常组、模型组、交泰丸不同配伍比例组,采用对氯苯丙氨酸(嗍)失眠模型,以高效液相和放免法检测大脑中逢核五羟色氨(5-HT)、肾上腺素(E)、去甲肾上腺素(NE)、多巴胺(DA)、外周血促肾上腺皮质激素(ACTH)含量变化,同时采用反相高效液相法测定黄连和肉桂不同比例配伍后的五种有效成分小檗碱、药根碱、巴马亭、桂皮醛和肉桂酸的质量百分含量变化趋势。结果:黄连与肉桂10:1组可以显著升高5-HT含量(P〈0.01),其E、NE、DA、ACTH含量也有升高,但不超过正常值。在黄连与肉桂不同比例的配伍中,黄连生物碱含量随肉桂剂量的增加而减少。结论:交泰丸配伍比例以10:1为最优,其镇静催眠的成分主要在黄连生物碱,肉桂成分在其中发挥协同作用。  相似文献   
32.
在针灸处方中,腧穴的配伍既有协同作用,也可能对应存在拮抗效应.本文结合相关文献,从协同作用和拮抗效应两方面进行分析探讨,以期对腧穴配伍效率研究提供一定的参考,指导临床和科研实践.  相似文献   
33.
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.  相似文献   
34.
新型MAO钛基生物材料的血液相容性研究   总被引:1,自引:1,他引:1  
目的初步评价新型钛基材料的血液相容性。方法采用新西兰大白兔新鲜全血,抗凝后分别与实验组和阳性对照、阴性对照组接触,用紫外-可见光分光光度计比色,评价各组的溶血率。实验符合国际化标准组织规定要求。结果新型微弧氧化钛基材料直接接触溶血率为0.79%,符合医用材料的溶血率不大于5%的要求。结论新型钛基材料具有良好的血液相容性。  相似文献   
35.
葡甘聚糖-胶原蛋白-壳聚糖共混膜(I)   总被引:2,自引:0,他引:2  
用溶液共混法制备了葡甘聚糖-胶原蛋白-壳聚糖(KCCS)共混膜。并用FT-IR,X-RD,SEM及透光率表征了膜的结构,同时测试了膜的抗张强度、断裂伸长率、吸水率、透水汽性、渗透性和吸附性。结果表明:共混膜中葡甘聚糖、胶原蛋白及壳聚糖之间存在着强烈的相互作用和良好的相容性,三者共混明显改善了纯聚合物和二元膜的性能。以共混膜为载体培养内皮细胞,发现共混膜具有良好的细胞相容性,预示着共混膜可作为潜在的组织工程支架材料。  相似文献   
36.
Using 12 healthy male subjects, the dynamic motor ability of individual fingers was investigated under four different finger tapping conditions. These were: maximum speed tapping with one finger (single-finger tapping), alternate movement of two fingers (double-finger tapping), double-finger tapping in an unsupported condition, and submaximum constant speed tapping with one finger in a passive manner. Key-contact forces for all fingers and the movement velocity of the tapping finger were monitored. With the exception of the unsupported condition, non-tapping fingers were maintained in contact with designated keys during the tapping tasks. It was found that the index finger attained the fastest cadence and greatest movement velocity, followed by the middle, little and ring fingers, respectively. Subjective assessment of rank order of "difficulty" of tapping by the subjects was highly correlated with tapping cadence. Thus dynamic motor function, as indicated by rapid, repetitive movement, differs among the individual fingers. Parallel changes were observed in the key-contact force of the neighboring non-tapping fingers during tapping. The range of the non-tapping finger forces was largest during tapping by the ring finger. A similar trend was found for passive tapping, during which the magnitude of key-contact force was less than one-third of that observed during active tapping. The lower cadence achieved by the ring finger may be attributed more to a lack of independence at the level of voluntary neuromuscular control, than to innate mechanical interaction with the other fingers. Tapping cadence of each finger was lower for the double-finger mode than for the single-finger mode. The magnitude of the observed decrease in cadence during double-finger tapping was, on the other hand, strongly dependent on finger-combination. The decrease was smallest for the index-middle finger-combination, and greatest for the ring-little finger-combination. Compatibilities with other fingers can play an essential role in the dynamic motor function of individual fingers. During the unsupported task, in which interactions were diminished by allowing all fingers to move freely, tapping cadence increased markedly. Therefore, the lower cadences observed in specific finger-combinations may be partly attributed to anatomical and neural interdigit interactions.  相似文献   
37.
Delayed flanker effects on lateralized readiness potentials   总被引:1,自引:0,他引:1  
When participants were required to respond to a relevant central target and ignore irrelevant flanking stimuli, the flankers produced a response compatibility effect. Electrophysiological studies have shown that irrelevant flanker stimuli can affect the motor system. The present experiments further examined the characteristics of flanker effects on the motor system. Sixty participants responded in the flanker task to arrows (experiment 1) or letters (experiment 2). To examine time and extent of flanker effects on the motor system, target onset was delayed with blocked or random stimulus-onset asynchronies (SOA). With SOA of 0 and 100 ms, flanker effects on behavioral measures were reduced in random as compared to blocked conditions, but enhanced with SOA of 400 ms. With SOA of 400 ms, flanker effects on the early lateralized readiness potentials (LRP) were reduced in blocked as compared to random conditions, indicating that the onset of flanker effects on the LRP was delayed. Response-locked LRPs suggest that flanker and target stimuli activate the motor system successively. Findings challenge current theories of the flanker compatibility effect.  相似文献   
38.
金属表面TiO2薄膜的溶胶-凝胶法制备及其血液相容性研究   总被引:8,自引:1,他引:8  
通过溶胶 凝胶法制备TiO2 薄膜对 316L不锈钢和NiTi形状记忆合金进行表面改性处理。研究发现 ,经 5 0 0℃处理 1h的薄膜结构致密 ,膜层均匀平滑 ,薄膜主要由锐钛矿相TiO2 构成 ,随热处理温度的提高 ,锐钛矿相逐渐转变为金红石相。电化学腐蚀和动态凝血时间及溶血率测试表明 ,通过溶胶 凝胶法制备TiO2 膜进行表面改性的 316L不锈钢和NiTi合金的抗模拟体液腐蚀性提高 ,动态凝血时间延长 ,溶血率下降 ,说明溶胶 凝胶法制备TiO2 膜可以提高金属植入物的血液相容性  相似文献   
39.
It is well known thathuman blood vessel hasan innermembrane constituted bylipid-protein LB (Langmuir-Blodgett) bilayer membrane,and exhibits an excellentanti-coagulant property.If we prepare biomaterials to imitate the structures andcompositions of the in…  相似文献   
40.
介入用聚氨酯材料的血液相容性研究   总被引:4,自引:2,他引:4  
介入导管优良的血液相容性是确保血管内介入技术安全可靠进行的重要因素,我们对自己合成的四种介入导管用聚氨酯材料的血液相容性进行了评价,包括溶血试验、血小板黏试验、动态凝血时间试验和动态血栓形成实验。结果表明,其中的H50-100和H60-100具有优良的血液相容性,完全可以用作介入导管材料。此外,还讨论了聚氨酯结构与血液相容性的关系。  相似文献   
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