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101.
梁建宁  李波 《中南药学》2004,2(4):224-226
目的完善复方杜仲片的质量标准.方法对方中的牛膝、益母草进行TLC鉴别,对黄芩采用HPLC法定量,色谱条件为Kromasil-C18柱,以甲醇-水-磷酸(45:55:0.2)为流动相;检测波长为315 nm;流速1.0 mL·min-1.结果在选定的薄层条件下,牛膝、益母草的薄层图谱清晰,分离度好.黄芩苷在0.537 66~2.688μg范围内具有良好的线性关系,其回归方程为:A=39 094.51 C-800.14,r=0.999 9.平均回收率为96.5%,RSD=2.1%.结论实验方法操作简单,可以用来控制本制剂质量.  相似文献   
102.
目的在大鼠杏仁核点燃模型研究MK-801(地佐西平)及其联合用药的抗癫痫作用。方法建立大鼠杏仁核慢性电刺激点燃模型,测定不同剂量的MK-801对点燃模型各项指标的影响,探讨MK-801与其他抗癫痫药的协同作用,用氨基脲诱发的小鼠惊厥模型测定MK-801抗惊厥作用。 结果MK-801(0.1~0.25 mg·kg-1)可剂量依赖性抑制杏仁核点燃,缩短后放电时程,降低Racine's分级;在对点燃均无明显影响的剂量下,MK-801(0.05 mg·kg-1)与抗癫痫药(苯巴比妥、丙戊酸及尼卡地平)合用可缩短后放电时程或降低Racine's分级。MK-801(0.1~0.25 mg·kg-1)显著降低小鼠氨基脲诱发的发作潜伏期、惊厥发生率和死亡率。结论MK-801具有抑制大鼠杏仁核点燃的作用,增强苯巴比妥、丙戊酸及尼卡地平的抗癫痫活性,为临床的合并用药提供实验依据。  相似文献   
103.
葛根素对小鼠和大鼠肝微粒体细胞色素P450的影响   总被引:10,自引:4,他引:10  
葛根素(puerarin)是豆科植物葛根的主要有效成分,具有扩血管、抗血小板、降血压、降血糖、改善微循环等作用,广泛用于心脑血管疾病的防治[1].因联合用药日益普遍,使药物间的相互作用倍受重视.肝微粒体细胞色素P450(cytochrome P450, CYP)是参与药物代谢的重要酶系,药物对CYP活性的影响是药物间相互作用的重要机制之一.本研究探讨了葛根素腹腔注射对小鼠和大鼠肝微粒体CYP活性的影响.  相似文献   
104.
反相高效液相色谱法测定风湿骨康片中士的宁的含量   总被引:5,自引:0,他引:5  
目的:建立RP-HPLC法测定风湿骨康片中士的宁的含量,完善质量标准.方法:采用Hyper-C18柱,0.03mol·L-1甲酸溶液(用三乙胺调节pH至3.0±0.1)-乙腈(78∶22)为流动相,254nm为检测波长.结果:测得线性范围0.416μg~4.992μg(r=0.9998),平均回收率98.65%,RSD为1.88%(n=5).结论:本法简便,准确,专属性强.  相似文献   
105.
甲磺酸加替沙星片治疗急性细菌性感染的细菌学疗效   总被引:6,自引:2,他引:6  
目的评价甲磺酸加替沙星片治疗急性细菌性感染疾病的细菌学疗效. 方法以盐酸左氧氟沙星片为对照药,采用多中心随机盲法阳性对照平行试验设计方法,评价甲磺酸加替沙星片治疗急性细菌性感染的细菌学疗效. 结果甲磺酸加替沙星片组和盐酸左氧氟沙星片组细菌分离阳性率分别为77.42%和80.99%;两组细菌清除率分别为 97.92%和97.96%;对不同致病菌感染有效率分别为83.33%~100%和80%~100%;以上结果两组差异无统计学意义;纸片药敏试验结果表明加替沙星、左氧氟沙星、氧氟沙星、环丙沙星和司帕沙星的细菌敏感率分别为93.81%、93.30%、91.24%、84.54%和87.11%;从MIC90结果看,加替沙星对多数致病菌的抗菌活性略强于左氧氟沙星. 结论甲磺酸加替沙星片具有良好的细菌学疗效.  相似文献   
106.
【摘要】 目的 探讨健胃愈疡片联合三联疗法治疗反流性食管炎的临床疗效。方法 选择2015年2月~2017年2月我院接诊的90例反流性食管炎患者,通过随机数表法分为观察组和对照组各45例,在基础治疗上,对照组给予三联疗法(奥美拉唑+甲硝唑+阿莫西林)治疗,观察组联合健胃愈疡片治疗,两组均连续治疗4周。比较两组治疗前后血清胃泌素(GAS)、一氧化氮(NO)、生长激素释放多肽(Ghrelin)、瘦素(Leptin)和中医证候积分的变化,并比较治疗后粘膜愈合率及临床疗效。结果 治疗后,两组血清GAS、Ghrelin较治疗前均显著升高,血清NO、Leptin显著降低(P<005),观察组血清GAS、Ghrelin明显高于对照组,血清NO、Leptin明显比对照组低(P<005);治疗后,两组烧心、反酸、胸痛症状积分较治疗前均显著降低(P<005),观察组烧心、反酸、胸痛症状积分均明显比对照组低(P<005);观察组粘膜愈合率明显高于对照组(P<005);观察组临床总有效率明显高于对照组(P<005)。结论 健胃愈疡片联合三联疗法治疗反流性食管炎效果显著,可有效促进食管粘膜愈合、缓解临床症状,促进临床疗效提高,可在临床推广应用。  相似文献   
107.
Context: The compressibility and compatibility of a powder formulation is usually determined by compaction and following destructive tensile strength and relative density measurement of the final compact.

Objective: In this study, a non-destructive method with Near-Infrared Spectroscopy (NIRS) was designed and evaluated for the measurement of powder compressibility and compactibility.

Materials and Methods: 12 different formulations with a wide range of difference in properties were investigated by compaction and analysis of the resulting tablets. Two similar tablet batches were produced with every formulation. Relative density and tensile strength were measured with the traditional, destructive method on one tablet batch while a newly developed non-destructive chemometric NIRS method was applied for the second batch. The outcomes of the two approaches were compared to validate the developed method. All data sets were applied to three established mathematical equations to calculate equation factors, which are claimed to represent the formulation compressibility and compactibility. The study focus was set on the equation factor value comparison between the traditional and the newly designed method.

Results & Discussion: The results showed a high similarity between the outcomes of the two methods. An essential difference was noticed for the outcomes of the equation factors after application to the Leuenberger equation.

Conclusion: The approach with the NIRS is suggested as a promising tool for a reliable inline quality monitoring in the tablet manufacturing process.  相似文献   
108.
Dry foam formulation technology is alternative approach to enhance dissolution of the drug. Sildenafil citrate was suspended in sodium dodecyl sulfate solution and adding a mixture of maltodextrin and mannitol as diluent to form a paste. Sildenafil citrate paste was passed through a nozzle spray bottle to obtain smooth foam. The homogeneous foam was dried in a vacuum oven and sieved to obtain dry foam granules. The granules were mixed with croscarmellose sodium, magnesium stearate and compressed into tablet. All formulations were evaluated for their physicochemical properties and dissolution profiles. All the tested excipients were compatible with sildenafil citrate by both differential scanning calorimetry (DSC) and infrared (IR) analysis. There are no X-ray diffraction (XRD) peaks representing crystals of sildenafil citrate observed form dry foam formulations. The hardness of tablets was about 5?kg, friability test <1% with a disintegration time <5?min. The sildenafil citrate dry foam tablet had higher dissolution rate in 0.1 N HCl in comparison with commercial sildenafil citrate tablet, sildenafil citrate prepared by direct compression and wet granulation method. Sildenafil citrate dry foam tablet with the high-level composition of surfactant, water and diluent showed enhanced dissolution rate than that of the lower-level composition of these excipients. This formulation was stable under accelerated conditions for at least 6 months.  相似文献   
109.
The objective of this investigation was to prepare the shellac wax matrix tablets by fusion and molding technique incorporated with Lutrol in different ratios to modify the hydrophobicity of matrix tablet. The matrix tablets with single drug were loaded either with propranolol hydrochloride or hydrochlorothiazide as hydrophilic and hydrophobic model drugs, and a dual drug formula was also prepared. The single and dual drug release patterns were studied in a dissolution apparatus using distilled water as medium. Propranolol hydrochloride released from matrix was easier than hydrochlorothiazide. Drug release from shellac wax matrix could be enhanced by incorporation of Lutrol. However retardation of drug release from some matrix tablets was evident for the systems that could form dispersion in the dissolution medium. The gel network from high content of Lutrol was hexagonal which was a dense and more compact structure than the other structures found when low amounts of Lutrol were present in the formula. Therefore, the formulae with high content of Lutrol could prolong drug release more efficiently than those containing low content of Lutrol. Hence shellac wax matrix could modulate the drug release with the addition of Lutrol. Sustainable dual drug release was also obtained from these developed matrix tablets. Thus shellac wax-Lutrol component could be used as a potential matrix tablet prepared with fusion and molding technique with excellent controlled drug release.  相似文献   
110.
Context: Brain oxidative reactions are involved in epilepsy as well as neurodegenerative diseases. In animal convulsion models, some anticonvulsants have been found to suppress oxidative reactions associated with convulsions. However, the effect of anticonvulsants on brain oxidative reactions has not fully been clarified.

Objective: Midazolam and phenobarbital are often used as an intravenous anesthetic, and are known to have anticonvulsive effect, but antioxidative effect of these drugs has rarely been studied. Thus, the purpose of this study was to evaluate the effects of these drugs on the degree of convulsions and brain oxidative reactions in an animal convulsion model.

Materials and methods: In order to evaluate brain oxidative reactions, we measured malondialdehyde (MDA) level and heme oxygenase (HO)-1 mRNA expression level in the brain of mice in a convulsion model generated by a single injection of pentylenetetrazole (PTZ). We evaluated the effects of midazolam and phenobarbital on the degree of PTZ-induced convulsions and on the changes in brain MDA level and HO-1 mRNA expression level.

Results: After PTZ injection, severe convulsions were observed in all mice. MDA level was increased in the whole brain, while HO-1 mRNA expression level was increased only in the hippocampus. Both midazolam and phenobarbital prevented the convulsions and suppressed the increase in both MDA level and HO-1 mRNA expression level in the brain.

Conclusion: In this study, both midazolam and phenobarbital suppressed PTZ-induced MDA and HO-1 reactions in the brain, suggesting that these drugs inhibit brain oxidative reactions in a convulsion model.  相似文献   
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