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11.
Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C max, higher values of t max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.  相似文献   
12.
Myasthenia-like syndrome induced by cardiovascular agents. Report of a case   总被引:1,自引:0,他引:1  
The case of a myasthenia-like syndrome induced by cardiovascular drugs is reported. The clinical and electrophysiological features of the case are discussed.
Sommario Viene descritto il caso di una sindrome miastenica indotta da farmaci efficaci sul sistema cardiovascolare. Vengono analizzate e discusse le principali caratteristiche cliniche ed elettrofisiologiche del caso.
  相似文献   
13.
Since 1903, Marchiafava‐Bignami disease has been recognized as a rare syndrome with focal demyelination and necrosis in the corpus callosum, which is usually found in chronic alcoholics. It extends into the neighboring white matter and occasionally as far as the subcortical regions. We report a Japanese patient with Marchiafava‐Bignami disease associated with alcohol abuse, who had traveled around Western Europe, North America and China for more than 30 years. As he suffered extreme delirium in the early stages we administered a low dose (10 mg) of mianserin hydrochloride. He was very irritable and uncooperative on admission, after 20 days his delirium had disappeared and his temper had become very calm and mild. After 40 days, his intelligence level increased substantially as measured by various neuropsychological tests.  相似文献   
14.
目的探讨达芬霖与肾上腺素在鼻内窥镜手术中的应用价值。方法观察达芬霖、肾上腺素分别在鼻内窥镜手术应用中对患者血压、心率的影响,观察出现反跳性鼻腔黏膜充血肿胀的时间和例数,并进行对比讨论。结果在达芬霖应用前后,30例患者的血压、心率变化差异无显著性,在肾上腺素应用前后,30例患者的血压、心率变化差异也无显著性,60例手术均在1 ̄3h内完成,达芬霖组无1例出现反跳性鼻腔黏膜充血肿胀,肾上腺素组有6例出现轻微的反跳性鼻腔黏膜充血肿胀,达芬霖组平均出血量248mL,肾上腺素组平均出血量120mL,P<0.05。结论达芬霖、肾上腺素作为鼻黏膜血管减充血剂和麻醉辅助药,常规用于鼻内窥镜手术是安全、有效的,用肾上腺素优于用达芬霖。  相似文献   
15.
本文采用紫外分光光度法对国产盐酸吗啡普通片及合资厂产硫酸吗啡控释片于蒸馏水、人工胃液、人工肠液中进行体外溶出度和释放度测定。结果表明,两种片剂的溶释均符合中国药典95版标准,控释片在人工肠液中溶释参数T50、Td、m与在蒸馏水及人工胃液中的溶释参数差异具显著性(P<0.01),在人工肠液中的释放过程明显缓慢。  相似文献   
16.
本文报道pH指示剂吸收度比值法测定盐酸乙胺丁醇的含量。该法采用指示剂为0.05%茜素黄R,测定波长374nm和500nm;标准液为0.1mol/L NaOH;仪器为WFZ-800D_2型分光光度计。测得三批盐酸乙胺丁醇的含量分别为99.5±0.04%,99.4±0.05%和99.6±0.03%.同时与药典法比较,结果一致。  相似文献   
17.
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively, throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing. The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively, in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum. The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed from the circulation to the brain with low penetrability. Received: 30 October 1996/Final version: 16 December 1996  相似文献   
18.
目的建立HPLC法测定复方氨酚苯海拉明片中盐酸麻黄碱和盐酸苯海拉明的含量。方法用Kromasil C18(250 mm×4.6 mm,5μm)色谱柱;流动相甲醇-乙腈-1%十二烷基硫酸钠溶液(26∶32∶42)(冰醋酸调pH值3.1),检测波长257 nm。结果线性范围,盐酸麻黄碱:1.228 8~11.059 2μg,r=0.999 9,盐酸苯海拉明:1.216 8~10.951 2μg,r=1.000 0;平均回收率,盐酸麻黄碱98.79%,RSD%=0.59%,盐酸苯海拉明100.44%,RSD%=0.57%。结论本方法简便、准确、灵敏度高、重现性好,可更好地控制本品的质量。  相似文献   
19.
目的:探索固体自乳化释放药系统,研制自乳化缓释片,考察体外释药行为。方法:以盐酸维拉帕米(Verpamil Hydrochloride,VH)为模型药物,以吐温80(Tween80),豆磷脂(sbpc)为乳化剂,以羟丙甲纤维素(HPMC),卡波普(carbopol)为骨架材料,制备自乳化缓释片。结果:以含吐温80和豆磷脂10%,羟丙甲纤维素和卡波普30%的处方乳化效果好,体外释药符合要求。结论:通过调节乳化剂和骨架材料的比例,可以获得理想的自乳化固体缓释制剂。  相似文献   
20.
对氯卞氯和苯经付克反应,光溴化,得到4-氯二苯基溴甲烷,然后经与羟乙基哌嗪缩合、与氯乙酸钠反应、加盐酸成盐、精制得西替利嗪盐酸盐,总收率为29%。  相似文献   
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