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91.
92.
两类胃酸分泌抑制剂治疗急性消化性溃疡出血的比较研究 总被引:1,自引:1,他引:0
目的 比较抑酸药 H2 受体拮抗剂 (H2 A)与质子泵抑制剂 (PPI)对消化性溃疡出血的疗效 .方法 130只 SD大鼠随机分成 6组 ,制备急性胃溃疡出血模型 ,以不同 p H值的缓冲液冲洗胃溃疡部位后记录其胃粘膜出血时间 (GMBT) .2 2 4例消化性溃疡急性出血患者 ,随机分 2组 ,2 4h内洛赛克组静滴 40 mg洛赛克 ,法莫替丁组静滴 40 mg法莫替丁 ,动态测定给药前 1h及给药后 2 4h胃内 p H值 . 3回顾性分析2 72例应用洛赛克 (4 0 m g静滴 ,1次· d- 1 )与 2 70例应用法莫替丁 (4 0 mg静滴 ,2次· d- 1 )的消化性溃疡出血患者手术率与死亡率 .结果 当 p H≥ 6 .0时大鼠 GMBT明显缩短 (P<0 .0 5 ) .胃内 p H值监测结果 ,用药后各组 p H>4.0 ,p H>6 .0的时间 ,洛赛克组比法莫替丁组显著延长 (P<0 .0 1) .洛赛克治疗组手术率比法莫替丁治疗组明显减低 (P<0 .0 5 ) ,而死亡率无显著差异 .结论 对急性消化性溃疡出血 ,质子泵抑制剂的抑酸止血效果明显高于 H2 受体拮抗剂 相似文献
93.
为了探讨红细胞膜Ca运转对慢性肾功能不全的影响,我们应用放射性同位素~(45)Ca示踪技术对15例慢性肾功能不全者进行红细胞膜钙内流(Ecc)及钙泵活性(Ecp)检测,并使用氨氯地平进行干预,结果发现:①慢性肾功能不全Ecc高于正常组;Ecp低于正常组。②经氨氯地平5~10mg每日1次干预4~6周后检测,Ecc下降,Ecp升高。BUN、Cr、24h尿蛋白均改善,初步显示了氨氯地平延缓肾衰进展的效果。 相似文献
94.
95.
关节灵片镇痛、抗炎作用的实验研究 总被引:1,自引:0,他引:1
为探讨关节灵片的镇痛、抗炎作用,用热板法和扭体法观察该药镇痛作用,结果关节灵片为不同剂量灌胃给药对小鼠热致痛和醋酸致痛均有明显抗痛作用,呈现一定的量效关系;关节灵片对二甲苯所致炎性水肿亦有显著的抑制作用。提示关节灵具有较好的镇痛抗炎作用。 相似文献
96.
双氯酚酸钠米索前列醇片的抗炎作用研究 总被引:3,自引:0,他引:3
双氯酚酸钠米索前列醇片(DSMT)(20,10mg/kg)连续2d灌胃给药可显著地抑制二甲苯所致鼠耳肿胀(P〈0.01,P〈0.05);DSMT(15,7.5mg/kg)灌胃给药均可非常显著抑制角叉菜胶至炎后3h内大鼠足肿胀;DSMT高、低剂量组(15,7.5mg/kg)灌胃给药7ddisplay structure 相似文献
97.
人工心脏(血泵)一直存在泵体对血细胞剪切力过大和流速过快容易引起溶血的问题。为了研究人体正常血压情况下,血泵内部剪切力和速度场的分布情况,选择圆盘泵叶轮代替传统离心泵叶轮,对两种模型进行数值计算,分析不同叶轮内部剪切力和速度场的分布规律。研究表明传统离心泵内部流速高,叶片表面剪切力大,对血细胞的伤害大。圆盘泵相比传统离心泵,剪切力更小,流场速度分布均匀,流速更小。和传统离心泵相比,不同转速下圆盘泵能降低溶血的发生率。圆盘泵叶片数为6片时,抗溶血性能更好。研究结果为血泵的优化提供理论依据。 相似文献
98.
Yang Weilian Barth Rolf F. Rotaru Joan H. Moeschberger Melvin L. Joel Darrel D. Nawrocky Marta M. Goodman Joseph H. 《Journal of neuro-oncology》1997,33(1-2):59-70
Boronophenylalanine (BPA) has been used for boron neutron capture therapy (BNCT) of brain tumors in both experimental animals and humans. The purpose of the present study was to determine if the efficacy of BNCT could be enhanced by means of intracarotid (i.c.) injection of BPA with or without blood-brain barrier disruption (BBB-D) and neutron irradiation using a rat brain tumor model. For biodistribution studies, F98 glioma cells were implanted stereotactically into the brains of Fischer rats, and12 days later BBB-D was carried out by i.c. infusion of 25% mannitol (1.373 mOsmol/ml), followed immediately by i.c. administration of 300, 500 or 800 mg of BPA/kg body weight (b.w.). At the 500 mg dose a fourfold increase in tumor boron concentration (94.5 g/g) was seen at 2.5 hours after BBB-D, compared to 20.8 g/g in i.v. injected animals. The best composite tumor to normal tissue ratios were observed at 2.5 hours after BBB-D, at which time the tumor: blood (T: Bl) ratio was10.9, and the tumor: brain (T: Br) ratio was 7.5, compared to 3.2 and 5.0 respectively for i.v. injected rats. In contrast, animals that had received i.c. BPA without BBB-D had T: Bl and T: Br ratios of 8.5 and 5.9, respectively, and the tumor boron concentration was 42.7g/g. For therapy experiments, initiated 14 days after intracerebral implantation of F98 glioma cells, 500 mg/kg b.w. of BPA were administered i.v. or i.c. with or without BBB-D, and the animals were irradiated 2.5 hourslater at the Brookhaven Medical Research Reactor with a collimated beam of thermal neutrons delivered to the head. The mean survival time for untreated control rats was 24 ± 3 days, 30 ± 2 days for irradiated controls, 37 ± 3 days for those receiving i.v. BPA, 52 ± 15 days for rats receiving i.c. BPA without BBB-D, and 95 ± 95 days for BBB-D followed by i.c. BPA and BNCT. The latter group had a 246% increase in life span (ILS) compared to untreated controls and a 124% ILS compared to that of i.v. injected animals. These survival data are the best ever obtained with the F98 glioma model and suggest that i.c. administration of BPA with or without BBB-D may be useful as a means to increase the efficacy of BNCT. 相似文献
99.
Van der Veen Jacoba Te Wierik Gerrit H. P. Van der Wal Liesbeth Eissens Anko C. Lerk Coenraad F. 《Pharmaceutical research》1994,11(4):499-502
Amylodextrin is a linear dextrin and can be produced by enzymatic hydrolysis of the -1,6 glycosidic bonds of amylopectin. Tablets compacted from pure amylodextrin showed good binding properties and did not disintegrate in aqueous media. Extended and decreasing drug release rates were found for tablets of 300 mg with a diameter of 9 mm containing 70% amylodextrin and 30% theophylline monohydrate, when compacted at 5 kN. Almost-constant drug release rates were obtained for these tablets when compacted at 10 or 15 kN. Nearly constant drug release rates were also shown for amylodextrin tablets with a drug load up to 75% compacted at 10 kN. Both release rate and release profile could be adjusted by selecting tablet thickness and incorporation of either lactose as a highly soluble excipient or talc as a hydrophobic excipient. 相似文献
100.
T. Kokufu N. Ihara N. Sugioka H. Koyama T. Ohta S. Mori K. Nakajima 《European journal of clinical pharmacology》1995,48(5):391-395
The effect of the new substituted benzimidazole proton pump inhibitor, lansoprazole, on pharmacokinetics and metabolism of theophylline has been studied in healthy adults given oral lansoprazole 30 mg once daily for 11 days. On Days 4 and 11 of 300 mg aminophylline was simultaneously administered orally and blood samples for theophylline analysis were taken over 24 h. Urine samples were collected for up to 24 h and were assayed for theophylline and its major metabolites 1,3-dimethyluric acid (1,3-DMU), 1-methyluric acid (1-MU) and 3-methylxanthine (3-MX). The pharmacokinetic parameters of theophylline were determined, and the urinary recovery of unchanged theophylline and its major metabolites were calculated.After administration of lansoprazole for 4 days, no significant alteration in the terminal elimination half-life (t
1/2) or the mean residence time (MRT) was detected. However, there was a significant decrease of about 13% in the area under the plasma concentration-time curve (AUC) and a significant increase of about 19% in the apparent clearance (CLapp). Lansoprazole treatment for 11 days caused a significant decrease of approximately 12% in t
1/2 and about 10% in the MRT of theophylline, although neither AUC nor CLapp showed a significant alteration. The excretion of 3-MX in the urine was significantly increased by about 20% after lansoprazole treatment for 4 and 11 days, although there was no significant alteration in the excretion of unchanged theophylline, 1,3-DMU or 1-MU.The results indicate that repeated administration of lansoprazole to humans induces the hepatic microsomal P-450-dependent drug oxidation system that mediates N-1-demethylation of theophylline, consequently increasing its metabolism. 相似文献