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141.
目的对比并探讨阿莫西林克拉维酸钾序贯疗法和静脉滴注2种不同给药方法治疗慢性支气管炎急性发作的临床疗效。方法将88例慢性支气管炎急性发作患者随机分为观察组和对照组各44例。观察组采用阿莫西林克拉维酸钾序贯疗法给药方案治疗,对照组采用阿莫西林克拉维酸钾静脉滴注给药方案治疗。对2组临床疗效、不良反应发生情况及平均住院时间进行比较。结果观察组临床总有效率为88.64%,对照组为86.36%,2组比较差异无统计学意义(P>0.05)。观察组不良反应发生率为4.55%,低于对照组的13.64%;观察组平均住院时间为(4.27±2.15)d,短于对照组的(11.12±2.43)d,差异均有统计学意义(P<0.05)。结论阿莫西林克拉维酸钾序贯疗法治疗慢性支气管炎急性发作,具有安全、有效、经济实用的优点,值得临床推广应用。 相似文献
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143.
H. C. Erbler 《Naunyn-Schmiedeberg's archives of pharmacology》1972,273(4):366-375
Summary The synthesis of aldosterone was stimulated in vitro by ACTH, dibutyryl-cyclic AMP, potassium ions and angiotensin II. Aldosterone was determined by a method involving two thin layer chromatographies (TLC), a periodic acid oxidation step, and a final esterification with heptafluorobutyric anhydride to prepare the aldosterone--lactone-heptafluorobutyrate for gas chromatographic quantification with electron-capture detection. The method is described in detail.Spironolactone (6×10–5–1×10–4M) added to the incubation medium inhibited the synthesis of aldosterone in a dose-dependent manner, while the production of corticosterone was not affected.It is concluded that spironolactone inhibits the conversion of corticosterone to aldosterone. 相似文献
144.
目的:探讨果糖二磷酸钾盐(FDPK)的抗心肌缺血再灌注心律失常作用及其机制。方法:取大鼠60只,随机分为模型对照组,FDPK大、中、小剂量组(80、40、20mg·kg-1),1,6-二磷酸果糖(FDP)组、氯化钾组共6组,采用冠脉结扎、松扎法建立心肌缺血再灌注心律失常模型,观察各组心律失常评分、心肌组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和三磷酸腺苷(ATP)酶的活性;此外,建立兔低钾血症模型,分别给予生理盐水、氯化钾、门冬氨酸钾镁和FDPK,检测各组细胞内钾离子浓度。结果:与模型对照组比较,FDPK(80、40mg·kg-1)能降低心律失常评分、升高SOD和ATP酶活性、降低MDA含量(P<0.01或P<0.05),并优于FDP组和氯化钾组;与给予生理盐水相比,FDPK能明显增加兔细胞内钾离子浓度(P<0.01)。结论:FDPK具有抗缺血再灌注心律失常作用,其作用机制可能与抗氧自由基产生和促进钾离子进入细胞有关。 相似文献
145.
Summary Ca2+ influx into stimulated endothelial cells is attenuated by depolarization. We hypothesized that Ca2+ influx is driven by the membrane potential and may be enhanced by hyperpolarizing drugs like activators of K+ channels. Therefore we studied the effects of pinacidil, cromakalim, and cicletanine on membrane currents and on the intracellular free calcium concentration ([Ca2+]i) in cultured endothelial cells from porcine aorta. In patch-clamped cells, pinacidil (1 mol/l) and cromakalim (1 mol/l) elicited outward currents carried by K+ and significantly prolonged the Ca2+-dependent K+ currents induced by bradykinin and ATP. Peak currents in response to bradykinin were not affected. In cells loaded with the fluorescent Ca2+ indicator indo-1 and prestimulated with thimerosal, pinacidil (0.1–1 mol/l elicited long-lasting increases in [Ca2+)i from 100 ± 10 to 550 ± 110 nmol/l. These effects were completely abolished in a medium containing 90 mmol/l K+. Similar results were obtained with cromakalim. Likewise, in cells stimulated with bradykinin, pinacidil raised [Ca2+]i when applied during the decline of [Ca2+]i after the initial peak. Cicletanine elicited K+ currents in resting and attenuated K+ currents in bradykinin-stimulated cells. It elevated [Ca2+]i even in the absence of extracellular Ca2+ and in K+-rich medium. Hence, the effects of cicletanine cannot be explained by direct actions on K+ channels. However, our studies demonstrate that pinacidil and cromakalim elevate [Ca2+]i secondary to their activation of K+ channels by inducing hyperpolarization and augmenting the driving force for potential-dependent Ca2+ influx. In this way, the two drugs may promote Ca2+-dependent formation of endothelium-derived relaxing factor.
Send offprint requests to A. Lückhoff at the above address 相似文献
146.
147.
摘要:目的建立HPLC法测定吡嘧司特钾滴眼液中苯扎溴铵和苯扎氯铵的含量。方法色谱柱:C18(4.6mm×150mm,5μm);流动相:0.02mol·L^-1庚烷磺酸钠溶液(含0.1%三乙胺,用磷酸调节PH为3.45±0.1)-乙腈(35:65);检测波长:210nm;柱温:40℃。结果苯扎溴铵在49.86~997.2ng范围内线性关系良好(r=0.9999),最小检出量为0.15ng,平均回收率为97.4%,RSD为1.0%;苯扎氯铵在9.912-24.78ng范围内呈良好的线性关系(r=0.9999),最小检出量为0.85ng,平均回收率为99.9%,RSD为1.0%。结论本方法简便、快速、准确、灵敏度高、重复性好,可用于吡嘧司特钾滴眼液中苯扎溴铵和苯扎氯铵的含量测定。 相似文献
148.
Gmyrek GB Sieradzka U Goluda M Gabryś M Sozański R Jerzak M Zbyryt I Chrobak A Chełmońska-Soyta A 《European journal of obstetrics, gynecology, and reproductive biology》2008,137(1):67-76
OBJECTIVE: The pathogenesis of endometriosis is related to functional changes in CD3+ and CD14+ cells observed both at the local and systemic level. Here we investigated whether, and if so, how the body compartment influences cytokine expression in stimulated peritoneal and peripheral CD3+ and CD14+ cells of women with endometriosis. STUDY DESIGN: Isolated peripheral blood (PB) and peritoneal fluid (PF) mononuclear cells from women with endometriosis were cultured under non-adherent conditions and stimulated with PMA and ionomycin for 6h to induce intracellular cytokine synthesis of TNF-alpha, IFN-gamma, and IL-8 by CD3+ cells or with LPS for 9h to produce TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 by CD14+ cells. RESULTS: The percentages of positive CD3+ cells stained for TNF-alpha and IFN-gamma were significantly higher and those stained for IL-8 were significantly lower in PF compared with PB, this being independent of the stage of endometriosis. In contrast, the percentages of CD14+ cells producing TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 were significantly higher in PB than PF of women with endometriosis. CONCLUSIONS: Monocytes/macrophages and lymphocytes derived from the peripheral and peritoneal compartments of women with endometriosis differentially respond to stimulated cytokine synthesis induction. However, it is difficult to state whether the observed phenomenon is more related to body compartment influence per se or to the presence of endometriosis. 相似文献
149.
目的 探讨人驱动蛋白分子Kif18A的各功能域在真核细胞中的定位。方法 构建驱动蛋白分子Kif18A野生型及各功能域(马达区、杆状区、尾区和马达区含部分杆状区)的绿色荧光蛋白表达质粒,分别转染人乳腺癌细胞MCF7,运用聚丙烯酰胺凝胶电泳和免疫印迹法验证各蛋白的表达,免疫荧光染色法分别对细胞进行微管蛋白和DNA染色,荧光显微镜下观察各绿色荧光融合蛋白的具体亚细胞定位。结果 有丝分裂间期,Kif18A蛋白分子的马达区绿色荧光沿微管分布,尾区在细胞核和微管上均有分布,杆状区则散在分布在胞质中;有丝分裂末期,Kif18A的马达区仍沿微管分布,而马达区含部分杆状区主要集中在中体部位。结论 Kif18A蛋白分子的马达区和尾区与微管共定位;尾区含核定位序列;马达区和杆状区共同作用才能使该蛋白在有丝分裂末期定位于中体。 相似文献
150.
目的探讨ICU-应用微量泵中心静脉高浓度补钾的有效性及安全性。方法回顾性分析ICU发生低钾血症78例患者的临床资料。随机分为常规组和高浓度组,每组各39例,补钾均在心电监护下进行。常规组钾浓度为40mmol/L,补钾速度为10~20mmol/h;高浓度组钾浓度为100~300mmol/L,补钾速度为加~200mmol/h,同时计算达到目标血钾浓度所需补钾量,监测两组血钾浓度、每小时尿量、达到目标血钾浓度所需时间及患者局部不良反应。结果两组患者治疗前均存在低钾血症,设定目标血钾浓度为4.0mmol/L,两组治疗前血钾浓度、所需补钾量比较差异无统计学意义,分别为(2.9±0.2)、(3.0±0.2)mmol/L和(85.2±8.7)、(92.3±7.6)mmol。常规组与高浓度组相比达到目标血钾浓度所需时间较长[(17.25±4.49)h比(5.67±0.75)h,P〈0.01]。结论在ICU严密监护下应用微量泵中心静脉高浓度补钾安全、有效.有一定的临床廊用价值。 相似文献