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1.
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant.  相似文献   
2.
 目的建立快速、准确、高灵敏度的测定中药平喘制剂中醋酸泼尼松和醋酸地塞米松检测的方法。方法采用UPLC-MS/PDA法,以甲醇-0.01mol·L-1醋酸铵(0.1%甲酸)缓冲溶液梯度洗脱,流速0.2mL·min-1,离子源为ESI源,正离子检测,对中药制剂中非法添加醋酸泼尼松和醋酸地塞米松进行定性定量分析,并对其裂解途径进行解析。结果6批受试制剂中有2批分别检测到有醋酸泼尼松和醋酸地塞米松。结论此方法选择性强、灵敏度高,可作为分析中药制剂中醋酸泼尼松和醋酸地塞米松的有效检测方法。  相似文献   
3.
维药无花果叶对抗大鼠泼尼松性骨质疏松的作用研究   总被引:1,自引:0,他引:1  
目的:研究维药无花果叶醇提物对泼尼松致大鼠骨质疏松的对抗作用。方法:将50只大鼠随机分成正常对照组、泼尼松模型组和维药无花果叶醇提物高、中、低(10mg/kg、20mg/kg、30mg/kg)剂量组,每组10只。分别灌胃相应药物,每日1次,连续8周后取血清检测生化指标,对骨进行组织切片检查,长度、宽度以及骨质的测量。结果:泼尼松模型组大鼠股骨重量、尺骨羟脯氨酸和骨钙含量比正常对照组明显降低,胫骨骨髓腔中脂肪组织增多(P〈0.01),血浆胆固醇(TG)含量上升、碱性磷酸酶(ALP)和高密度脂蛋白(吼)含量下降(P〈0.01)。维药无花果叶醇提组能有效提高骨的重量和骨质的含量(P〈0.01),减少骨髓腔中脂肪的含量,升高碱性磷酸酶和高密度脂蛋白含量(P〈0.01)。结论:泼尼松可抑制大鼠的,肾生长及引起骨丢失,而维药无花果叶醇提物可有良好的对抗作用。  相似文献   
4.
目的 探讨自制苏芪合剂对Ⅲ~Ⅳ级IgA肾病患者的疗效及患者T细胞功能的改善.方法 28例Ⅲ~Ⅳ级IgA肾病患者随机分为两组,对照组:醋酸泼尼松-日1mg,kg,隔日晨起顿服,盐酸苯那普利-日10mg;治疗组:在上述用药的基础上加用自制苏芪合剂.8周后,观察患者缓解率、T细胞功能及不良反应.结果 治疗组患者在缓解率、T细胞功能改善等方面优于对照组,且因糖皮质激素的使用而出现的不良反应少于对照组.结论 苏芪合剂联合治疗Ⅲ~Ⅳ级IgA肾病疗效显著并能有效改善T细胞功能.  相似文献   
5.
We investigated the regulation of the rat neuron-specific enolase gene using a transient transfection approach. Recent transgenic mouse studies have shown that a 1.8-kb segment of the ratNSE gene 5′ flanking region, including the first (noncoding) exon but not the first intron, is able to drive expression of a reporter gene in parallel with endogenousNSE. These data suggest thatcis-acting elements responsible for the spatial and temporal pattern ofNSE gene expression are located within the proximal 1.8 kb of the 5′ flanking sequence. To further investigate this region, we joined the 1.8-kb regulatory cassette to thecat reporter gene and generated a number of constructs in which the flanking sequence was progressively deleted from the 5′ end. These constructs were tested by transient transfection into neuronal and nonneuronal cells, followed by an assay for CAT activity. We found that as little as 255 bp of 5′ flanking sequence was able to confer cell type-specificity on the reporter gene. Further truncation to 120 bp of 5′ sequence resulted in a sharp downregulation of reporter activity in PC12 cells but a significant rise in both Neuro-2A neuroblastoma cells and nonneuronal Ltk- cells, indicating thatcis-acting elements controlling the regulation ofNSE in Ltk-, Neuro-2A, and PC12 cells may lie within the 135 bp region covered by this deletion. This region contains an AP-2 site and an element similar in sequence and position to a motif identified in the proximal promoter region of the neuron-specific peripherin gene. Reduction to 95 bp of 5′ sequence resulted in a slight downregulation of CAT activity in all cell lines tested, and further truncation to 65 bp of 5′ sequence caused a universal reduction to background levels of CAT activity, concomitant with the disruption of the basalNSE promoter. Our results show that the 5′ flanking region of theNSE gene is capable of conferring cell type-specificity on a heterologous gene in transfected cells and that elements responsible for this are located within the proximal 255 bp.  相似文献   
6.
重症肌无力患者泼尼松治疗前后免疫学指标的变化   总被引:3,自引:0,他引:3  
探讨泼尼松治疗重症肌无力(MG)免疫学机制。对382例MG患者在漏尼松中剂量冲击,小剂量维持疗法治疗前后,检测酰胆碱受体抗炎(AchRab),突触前膜抗体(PsMab),单个核细胞亚群(PBMC),肿瘤坏死因子(TNF),可溶性白介素-2受体(SIL-2R),β2-微球蛋白(β2-m),以及红细胞免疫功能的变化。结果表明:MG患者在泼尼松治疗前后多项免疫指标有显著性的变化。为泼尼松治疗MG提供了评定疗效的免疫学指标,进一步阐明了MG发病的免疫学机制。  相似文献   
7.
根据蓝四氮唑与泼尼松生成蓝色产物,并于525nm 波长处测定吸光度。测定条件为:反应管长度为3.8m(0.5mm id);流速为1.6ml/min;反应温度为55±0.5℃;注射样品溶液为100μl;本测定系统的测定速度可达100次/h;线性范围可达0.09mg/ml;检测限量为1.54μg/ml;测定结果的变异系数小于1%。  相似文献   
8.
The effect of cyclic 3,5-adenosine monophosphate (cAMP) on production of the enzyme chloramphenicol acetyltransferase (CAT) by whole bacterial cells was studied in strainsEscherichia coli CSH-2/R222 and WZ-78/R222 (cya855). CAT synthesis in strainE. coli WZ-78/R222 was shown to have an intensity only half as great as that of strainE. coli CSH-2/R222. The production of CAT by strainE. coli CSH-2/R222 was increased only very slightly by cAMP, but its effect on the production of this enzyme in strain WZ-78/R222 was appreciable.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR, N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 80, No. 10, pp. 65–66, October, 1975.  相似文献   
9.
本文介绍一种快速方便的外源基因在哺乳动物细胞中瞬间表达检测系统,即氯霉索乙酰转移酶检测系统。该项检测技术不仅对基因的调控顺序(Cis-acting elements)如启动子、增强子等检测提供了有效的工具,而且为真核基因在哺乳动物细胞表达体系中,质粒的构建及筛选提供了行之有效的手段。并介绍了该技术的全过程及其操作要点。  相似文献   
10.
Summary The oestrogenic component of oral contraceptives affects the activity of liver enzymes and the concentrations of plasma proteins implicated in steroid metabolism and transport. The present study was designed to determine these effects on the kinetics of prednisone and prednisolone. After an oral dose of prednisone, women on oral contraceptive steroids (n=10) had higher mean (±SD) area under the plasma concentration versus time curves of total (428±67 µg/ml/min vs 188±28 µg/ml/min, p<0.001) and unbound prednisolone (64±10 µg/ml/min vs 41±10 µg/ml/min, p<0.001) than women not taking oral contraceptive steroids (n=10). The differences were attributable to a lower non-renal clearance of prednisolone and to a higher apparent systemic availability of the drug in contraceptive users than in the controls. The affinity of albumin and transcortin for prednisolone was lower in women on oral contraceptives than in controls (p<0.001). Thus, altered kinetics and protein binding may account for the known increase in glucocorticoid efficacy by oestrogens.  相似文献   
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