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51.
目的:探讨抗肿瘤中药对癌细胞的繁殖起重要作用的ACPase、ATKPase、SDH、G-6-PDH在U14宫颈癌细胞中活性的影响。方法:荷瘤小鼠在第7d用药后6h处死,取腹水癌细胞涂片,固定显示,用细胞分光光度计测定酶活性。结果:中药合剂实验组细胞内ACPase、ATPase、SDH、G-6-PDH酶活性比生理盐水对照组显著降低(P<0.01),分别下降60%、40%、56%、70%,与环磷酰胺组比无显著性差异(P>0.05)。结论:抗肿瘤中药合剂能显著地抑制U14宫颈癌细胞内ACPase、ATPase、SDH、G-6-PDH活性,呈现抑瘤作用。 相似文献
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54.
Persisting cough developed in three children treated with converting enzyme inhibitors. The symptoms disappeared within 3–7 days after withdrawing medication. These observations in children complement previous reports in adults and indicate that cough may be induced by treatment with these agents. 相似文献
55.
T. N. RAMUTHAGA M. s. BORNMAN M. F. MAHOMED D. BOOMKER A. S. GREEF H. H. CREWE-BROWN S. REIF 《International journal of andrology》1994,17(1):9-12
Swabbing the urethrae of men has been the traditional approach for collecting specimens for detection of Chlamydia trachomatis . Recently, however, urine testing using enzyme immunoassay has yielded promising results. A total of 105 patients attending the Andrology Clinic at Ga Rankuwa Hospital, Medunsa were included in the study. These patients were asymptomatic and had no urethral discharge. Three endo-urethral swabs and first-catch urine were collected fiom each patient. The urethral swabs were used for enzyme immunoassay (EIA) (IDEIA 111), tissue culture and direct immonufluorescent antibody (DFA) test (IMAGEN) to detect C. trachomatis . In addition about 15–30 ml of first-catch urine, or urine collected at least 2h after the previous micturition, was collected for each patient for EIA testing. Fifteen (14.3%) of 105 patients were positive on urethral swab EIA, in comparison with the DFA test in which 14 (13.3%) were positive. Eight (7.8%) were positive in tissue culture. Urine EIA was positive in 17 (16.2%) patients, of whom five (4.8%) were positive in urine EIA only. All EIA positive urines were confirmed by DFA. We recommend that first-catch urine or urine collected at least 2h after the previous micturition in infertile males may be considered a suitable alternative to urethral swab for chlamydial diagnosis because it is noninvasive and nontraumatic. 相似文献
56.
在原发性高血压(EH)患者、大鼠腹主动脉狭窄和高盐摄入引起高血压模型上,观察到口服牛磺酸治疗4周后均明显降低平均动脉压和收缩压,42.2%的患者血压恢复正常,并能抑制EH患者和高血压大鼠血浆内皮素(ET)、血管紧张素II(AII)水平的升高,增加高血压大鼠血浆降钙素基因相关肽(CGRP)和主动脉组织中的牛磺酸含量.以上结果表明,牛磺酸在降压作用同时伴有缩血管物质的降低和舒血管物质的增加,为以牛磺酸作为降血压辅助药物提供了依据. 相似文献
57.
蝮蛇抗栓酶对骨内高压降压作用实验研究 总被引:12,自引:0,他引:12
本实验随机将家兔一侧后肢于膝关节伸直位夹板外固定5周,制成固定侧胫骨上端骨内高压模型。对其全身和局部血液流变学指标进行测定,发现全血粘度,血浆粘度增大,血沉增快,血浆纤维蛋白原含量明显增高。对上述模型应用蝮蛇抗栓酶(svate)连续治疗21天,骨内压降低,血液流变学各项指标亦降低。本实验结果显示,蝮蛇抗栓酶通过改善骨内高压状态下的异常血液流变学状态可使骨内高压降低,从而认为血液流变学疗法可能成为临床治疗骨内高压症的一种新手段,而蝮蛇抗栓酶可能为其中高效药物之一。 相似文献
58.
Jaroslav Salamoun Jo
rg Remien 《Journal of pharmaceutical and biomedical analysis》1992,10(10-12):931-936
The inhibiting compounds were separated by micro-column liquid chromatography in the mobile phase containing the natural substrate acetylcholine. A home-made packed bed microbioreactor system containing immobilized enzyme acetylcholinesterase (ACHE) in human red blood cell membrane and choline oxidase (CHO) from alcaligenes was used for the post-column conversion of acetylcholine to hydrogen peroxide which was detected by an electrochemical detector. The inhibition effect of the solutes caused a decrease in the acetylcholinesterase activity, a decrease in the formation of hydrogen peroxide and also a decrease in the response corresponding to the concentration of the solutes. The rate of the enzyme regeneration was also recorded. The micro-system was compared with a conventional LC system comprising commercially prepared enzyme reactor. The stability of the enzymes is at least 3 weeks at ambient temperature. The limit of detection depends on biological activity of inhibition and for galanthamine was 1 pmol. 相似文献
59.
对25例急性心肌梗塞(AMI)并左心功能不全患者早期应用血管紧张素转换酶抑制剂(ACEI)治疗的对照性临床分析,结果:用小剂量的ACEI治疗对患者心率、血压无显著的影响〔治疗前后心率分别为89.90±10.22次/分与89.42±8.19次/分,血压分别为15.37±3.46/9.74±2.32kPa(1kPa=7.5mmHg)〕和14.96±2.60/9.46±1.76kPa〕;对合并轻、中度泵衰竭患者的疗效显著,但对重度泵衰竭的疗效与对照组比较无显著性差异;治疗组恶性心律失常的发生率较对照组减低13.38%,警告性室早的发生率治疗组较对照组减少26.39%,但Ⅱ°~Ⅲ°房室传导阻滞的发生率治疗组高于对照组;两组4周病死率比较无显著性差异。作者认为:ACEI治疗AMI并轻、中度泵衰竭安全有效;ACEI有一定抗心律失常作用,但应注意传导系统的并发症,使用中应注意各种副作用的发生。 相似文献
60.
S. Gasic G. Heinz C. Kleinbloesem 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(4):436-440
Summary The renin-angiotensin system relevantly contributes to the maintenance of systemic vascular tone and there is experimental evidence that large amounts of angiotensin-converting enzyme (ACE) are present in peripheral vascular tissues, including resistance vessels. To determine and quantify peripheral vascular conversion of angiotensin-I (ANG-I) to angiotensin-II (ANG-II) across the human leg, the response of regional blood flow to local regional intra-arterial infusion of ANG-I and changes in associated ANG-I1 balance were evaluated during ANG-I infusion and following additional ACE inhibition. Ten sodium-loaded healthy men were enrolled in the study. Following cannulation of both femoral arteries and the right femoral vein, leg blood flow was determined (indocyanine-green dye-dilution method) at baseline conditions and during constant intra-arterial infusion of haemodynamically ineffective doses of ANG-I as well as following concomitant intra-arterial administration of low doses of the non-sulfhydril ACE inhibitor cilazapril. From the transfemoral arterio-venous differences in ANG-II plasma concentrations and the corresponding regional blood (plasma) flow, the ANG-II balance across the leg was calculated. Systemic blood pressure did not change throughout the trial, indicating that no major systemic effects were present during ANG-I infusion or concomitant ACE inhibition. Moreover, arterial ANG-II plasma concentrations were not significantly changed by ANG-I infusion. Leg blood flow decreased to below baseline values following ANG-I infusion, increasing again then in a dose-dependent manner during concomitant cilazapril administration. The calculated baseline ANG-II balance across the leg revealed a net extraction in 6 out of 10 subjects and a net ANG-II formation in 4. Following ANG-I, a shift towards net ANG-II formation or decrease in extraction was seen in 8 subjects, while 2 had no change in ANG-II balance.During concomitant ACE inhibition, ANG-II balance was again shifted towards net extraction or reduced formation. Our results confirm that, in man, considerable regional arterio-venous differences in ANG-II plasma concentrations are present, resulting in either net transfemoral extraction or net formation of the peptide. It is suggested that systemic vascular conversion of circulating ANG-I might contribute to the maintenance of peripheral vasuclar tone in man.
Send offprint requests to S. Gasic at the above address 相似文献