HPLC法测定复方氯霉素乳膏中氯霉素和丙酸倍氯米松含量

目的:建立测定复方氯霉素乳膏中氯霉素和丙酸倍氯米松含量的方法。方法:采用高效液相色谱法。色谱柱为Shim-pack VP-ODS,流动相为含乙腈-0.05mol.L-1磷酸二氢钾溶液,梯度洗脱,流速为1.0mL.min-1,检测波长为240nm,进样量为15μL。结果:氯霉素和丙酸倍氯米松检测浓度线性范围分别为47.6～238、2.96～14.8μg.mL-1(r=0.9999、0.9998),平均回收率分别为99.97%(RSD=0.84%,n=9)、99.28%(RSD=1.87%,n=9)。结论:本法简便、准确,可用于复方氯霉素乳膏的含量测定。     

五种氨基糖甙类抗生素联用氯霉素的急性毒性实验

目的 :探讨五种氨基糖甙类抗生素 (卡那霉素、丁胺卡那霉素、小诺霉素、链霉素和大观霉素 )联用氯霉素时的急性毒性。方法 :通过小鼠急性毒性实验 ,观察五种氨基糖甙类抗生素单用及和氯霉素联用各组的中毒症状和死亡率 ;通过对大鼠呼吸的影响 ,观察丁胺卡那霉素联用氯霉素增毒作用。结果 :五种氨基糖甙类抗生素和氯霉素联用时死亡率显著高于单用组 (P<0 .0 1) ;丁胺卡那霉素与氯霉素联用组呼吸停止时间明显缩短 (P<0 .0 1)。结论 :所试五种氨基糖甙类抗生素联用氯霉素时均可出现明显的增毒作用     

人类XBP1基因5′上游DNA序列的转录激活功能分析

目的分析人类转录因子X-盒结合蛋白1（X-box binding protein Ⅰ，XBP1）基因启动子在不同细胞系中转录活性的差别，研究其转录调控机制。方法在对XBP1基因进行生物信息学分析的基础上，设计6种XBP1启动子缺失突变体，分别包括剧XBP1基因5’上游-1039～66bp、-859～66bp、-623～66bp、-351～66bp，-227—66bp、-227～-45bp，针对每一种缺失突变体构建相应的氯霉素乙酰转移酶（chloramphenicol acetyltansferase，CAT）报告基因载体，再分别瞬时转染K562、HepG2、NIH-3T3和LO2细胞，应用报告基因CAT瞬时表达系统，检测XBP1每一种缺失突变体在K562、HepG2、NIH-3T3和LO2 4种不同细胞中的活性差异，并进一步确定脚，基因启动子的具体调节部位。结果成功获得XBP1基因启动子6种缺失突变体的正确克隆和6种相应的报告基因载体p1—XBP1p，p2-XBP1p，p3-XBP1p，p4-XBP1p，p5-XBP1p，p6-XBP1p，每一种报告基因转染K562、HepG2、NIH-313和LO2 4种不同细胞系后，p4-XBP1p和p5-XBP1p在K562、HepG2细胞中的转录活性均高于其它报告载体，p5-XBP1p在HepG2细胞中转录活性最高；而6种报告基因载体在NIH-3T3小鼠成纤维细胞中不具有转录活性。结论。XBP1基因的转录激活能力在不同细胞中有所差异，其表达活性具有一定的细胞类型特异性，与细胞类型和细胞状态密切相关；XBP1基因启动子的-227～66bp区域是该启动子的核心部位，而且核心启动子区包括ATG翻译起始密码子的下游部位，这一部位是转录活性的重要部位，一旦缺失，XBP1基因启动子会丧失活性。     

Treatment of enteric fever in children on the basis of current trends of antimicrobial susceptibility of Salmonella enterica serovar typhi and paratyphi A

Purpose: Recent reports indicate decreased susceptibility of S. typhi to fluoroquinolones, especially ciprofloxacin. Chloramphenicol has been suggested as first line therapy of enteric fever in many studies. This is a prospective study that describes the trends of antimicrobial susceptibility of S. typhi and S. paratyphi A causing bacteraemia in children and reports therapeutic failure to ciprofloxacin and evaluates the possible use of chloramphenicol, ampicillin, ciprofloxacin and third generation cephalosporins as first line therapy in the treatment of enteric fever in children. Methods: The present study was conducted from April 2004 to March 2005 in a superspeciality children hospital at New Delhi. A total of 56 S. typhi and five S. paratyphi A isolates were obtained among the 673 blood cultures performed. Antimicrobial testing was done using disk diffusion technique (NCCLS method) for 13 antimicrobials and MICs were calculated for ampicillin, ciprofloxacin, chloramphenicol and cefotaxime. Analysis of data was done using WHONET software. Results: All 56 isolates of S. typhi were sensitive to amoxycillin+clavulanate, gentamicin, cefixime, cefotaxime and ceftazidime. Multidrug resistance (MDR, resistance to three drugs) was seen in 22 cases (39%) and resistance to five drugs was seen in 12 cases (21%). Only two isolates were resistant to chloramphenicol (3%). MIC₉₀ for ampicillin, chloramphenicol, ciprofloxacin and cefotaxime were 1.0 μg/ml, 4.0 μg/ml, 64 μg/ml and 0.125 μg/ml respectively. All S. paratyphi A isolates were sensitive to ampicillin and chloramphenicol and resistant to nalidixic acid.MIC distribution data for chloramphenicol revealed elevated MIC but still in susceptible range. Conclusions: There is an urgent need for further clinical studies to evaluate response to chloramphenicol in such cases. Antimicrobial susceptibility data and MIC distribution favour use of ampicillin as a drug of choice for the treatment of enteric fever. Third generation cephalosporins are also useful but their use should be restricted for complicated cases.     

甲砜霉素甘氨酸酯盐酸盐的合成研究.用电导率的方法测定α-卤代羰基化合物与乌洛托品成盐反应

具有活性较强基团α卤代羰基的化合物甲砜霉素氯乙酸酯和对硝基α溴代苯乙酮都能发生Ｄｅｌéｐｉｎｅ反应，在此过程中，与乌洛托品成盐反应的前后电导率有显著的变化，因而可用电导率的测定证明其与乌洛托品形成盐；并且可利用测定电导率变化跟踪反应过程与判断反应终点．     

吸收度线性组合分光光度法测定氯麻滴鼻液的含量

本文应用吸收度线性组合分光光度法,不经分离直接测定了氯麻滴鼻液的含量。于251nm、257nm 和278nm 波长处分别测定吸收值,通过单波长法和线性组合法分别测定计算氯霉素和盐酸麻黄素的含量。本法不受甘油的干扰,其平均回收率分别为98.91%(cv=0.54%)和101.47%(cv=0.69%)。     

氯霉素地塞米松搽剂的制备及其临床应用

目的介绍氯霉素地塞米松搽剂的制备,及其在轻中度寻常痤疮中的疗效。方法制备氯霉素地塞米松搽剂,并对其进行质量控制。分析其与氯霉素搽剂在轻中度寻常痤疮治疗过程中的临床疗效。结果本品制作简便,质量符合《中国药典》要求,与氯霉素搽剂比较,本品对轻中度寻常痤疮的治疗疗效更佳、不良反应更少。结论本品制备工艺可靠,质量可控,对轻中毒寻常痤疮的治疗疗效佳,不良反应少,是寻常痤疮治疗的好选择。     

HPLC梯度法测定复方氯霉素咪康唑乳膏中氯霉素和硝酸咪康唑的含量

目的:建立高效液相色谱法测定复方氯霉素咪康唑乳膏中氯霉素和硝酸咪康唑的含量的方法。方法:C18色谱柱,甲醇—0.5%醋酸铵水溶液—乙腈(17:66:17),8min时变为(45:10:45),流速1.0mL/min,检测波长227nm。结果:氯霉素与硝酸咪康唑在0.16~0.8mg/mL浓度范围内呈良好的线性关系。结论:各成分测定方法简便,重现性好。     

毛细管区带电泳法测定氯霉素滴眼液的含量及降解产物二醇物的控制

目的　采用毛细管区带电泳色谱法测定氯霉素滴眼液的含量 ,并对其中降解产物二醇物进行控制。方法　采用毛细管区带电泳法 (CZE)以 0 .0 5mol·L-1的磷酸盐缓冲液 (pH6 .0 )做运行液 ,运行电压 :18kV(运行电流 :70～ 80 μA) ;进样时间 :10s ;检测波长 2 14nm ;并以甲氧苄氨嘧啶 (TMP)为内标。结果　氯霉素和二醇物分别在 0 .2 39～ 2 .390mg·mL-1和 0 .0 18～0 .180mg·mL-1的范围内呈良好的线性关系 ,相关系数分别为r氯 =0 .9980和r二 =0 .9991。平均回收率分别为 98.2 7% (n=5 ) ,RSD =2 .1%和 98.44 % (n =5 ) ,RSD =1.7%。结论　本方法可同时测定氯霉素滴眼液中氯霉素与二醇物的含量。而且简便、快速、准确。     

HPLC法测定复方氯霉素乳膏中主药的含量

目的:建立以高效液相色谱法测定复方氯霉素乳膏中氯霉素与氨苯砜含量的方法。方法:色谱柱为Hypersil ODS,流动相为含0.1%庚烷磺酸钠的溶液(取0.1%庚烷磺酸钠溶液500mL与二甲基甲酰胺5mL、冰醋酸0.5mL,混匀)-乙腈(75∶25),流速为1.0mL·min-1,检测波长为272nm,进样量为20μL。结果:氯霉素与氨苯砜检测浓度的线性范围分别为25.59~153.54、12.57~75.42μg·mL-1(r=0.9999);平均回收率分别为100.62%(RSD=0.92%)、100.93%(RSD=1.22%)。结论:本方法简便、准确,可用于该复方制剂的含量测定。