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51.
The purpose of this trial was to study the additional anti-ischaemiceffects of amlodipine in coronary patients with ambulant ischaemiadespite beta-blocker therapy. Beta-blockers are the most effectivedrug therapy for reducing the frequency and duration of ambulatoryischaemic episodes. However, the therapeutic advantage of combinedcalcium antagonist-beta-blocker treatment remains questionable. Three hundred and thirteen patients with documented coronaryartery disease, a positive exercise test within 6 months beforeentry and background beta-blocker therapy, were screened. Inclusioncriteria (4 episodes of transient ST segment depression of 1.0 mm and/or 20 min of ischaemia) were demonstrated in a 48h ECG during the placebo run-in period in 84 (25%) of the patients.Eighty-nine percent of the ischaemic episodes were silent. Theeligible patients were then randomized in a 2-week, double-blind,parallel group study comparing placebo to amlodipune 10 mg dailyadded to the beta-blocker. The anti-ischaemic efficacy of thecombination therapy was assessed by 48 h ECG monitoring andexercise tests. Compared to placebo, amlodipine did not significantly reduceeither the frequency (3.7±4.3 vs 4±4.8 episodesin the amlodipune group) or the duration of ambulatory ischaemia(mean duration: 43.9±57.1 vs 39.6±65.7 min, totalduration 3.1±6.7 vs 2.8±6.1 h). Exercise-inducedST segment depression tended to decrease with amlodipine (58%vs 73% in the placebo group) and the ischaemia-free workloadcapacity was increased (+1.7 stage vs 0.7 stage in the placebogroup, P=0.08). These results suggest that 2 weeks treatment with amlodipinemay not provide any additional anti-ischaemic benefit in patientswith ambulant ischaemia resistant to a beta-blocker therapy.  相似文献   
52.
苦参生物碱的高效液相色谱法测定   总被引:51,自引:0,他引:51  
报道了苦参中五种主要生物碱——槐果碱、苦参碱、槐定、氧化槐果碱和氧化苦参碱的高效液相色谱测定法。用氨基键合相柱,乙腈—磷酸水溶液(pH 2)—无水乙醇(80:8:10)为流动相,220nm为检测波长。方法简便易行,可在15 min内完成测定。  相似文献   
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Background and Objective There are several sources that suggest that there is a link between allergy and sudden infant death syndrome. We endevavoured to look for evidence of an association between allergic disease and the risk of sudden infant death syndrome (SIDS). Methods A nationwide case-control study covering a region with 78% of all births in New Zealand during 1987–90. Interviews were completed with the parents of 393 (81.0% of total) infants who died from the sudden infant death syndrome (SIDS), and 1592 (88.4% of total) control families who were a representative sample of all hospital births in the study region. Results Eczema was reported in 13.9% control infants compared with only 8.0% of the SIDS infants, univariate odds ratio for this in terms of risk for SIDS was 0.56 (95% confidence interval 0.37, 0.84) for infants with eczema compared with those without. This lesser risk for SIDS was unchanged when adjusted for potential confounding factors. The risk of SIDS was not associated with reported cow's milk reactions or a family history of allergic symptoms once adjustments were made for possible confounding factors. Conclusion Infants with skin disorders identified by their parents as eczema had a low risk for SIDS. Families can be reassured that atopy is not a risk factor for SIDS.  相似文献   
54.
We investigated the relationship between myopia and peripheral refraction for distance and near vision by measuring peripheral refractive errors in 10 myopic and 10 emmetropic participants at viewing distances of 2.5 and 0.4 m. Measurements were made at the fovea, and at eccentricities of 10 degrees , 20 degrees and 30 degrees in the temporal and nasal hemispheres of the horizontal visual field. Our results showed that peripheral astigmatism increased with increasing eccentricity, but there was no significant difference between refractive error groups except at 30 degrees eccentricity in the temporal retina. Considering the Mean Spherical Equivalent errors, emmetropes became relatively myopic at peripheral eccentricities, but there was little change in myopes. The effect of viewing distance on astigmatism or Mean Spherical Equivalent error was not significant. Our results do not support the view that myopia is associated with changes in peripheral refraction during distance or near vision.  相似文献   
55.
本研究首次采用了较大的功率和剂量(5mW、10mW、18mW和25mW×60min)的He-Ne激光对实验性糖尿病新西兰兔进行了血管内照射,观察了其红细胞变形能力(RCD)随剂量和时间的变化。结果发现:①在未实验所选用的功率和剂量范围内,大剂量的照射对RCD的影响能较早地表现出来,且更持久。②在改善RCD的程度上,剂量(功率)越大,则越表现出优越性,特别是在照射后第1天和第3天,剂量越大的组其平均IF指数越小。③而照射12天以后各组无显著性差异,则说明一次照射不可能使RCD彻底恢复正常,所以在临床应用时,应进行多次照射。④从照后各天结果的相互比较可以看出,第三天的效果最好,这一结果可为疗程设计提供参考。未次实验过程中未发现溶血现象。  相似文献   
56.
BACKGROUND: The benefit of combined mechanical and pharmacologic methods for venous thromboembolism prevention after abdominal surgery has not been clearly established. OBJECTIVES: To compare the efficacy and safety of fondaparinux in conjunction with intermittent pneumatic compression vs. intermittent pneumatic compression alone in this context. PATIENTS AND METHODS: This was a randomized, double-blind, placebo-controlled superiority trial. Patients aged at least 40 years undergoing abdominal surgery were randomized to receive either fondaparinux 2.5 mg or placebo s.c. for 5-9 days, starting 6-8 h postoperatively. All patients received intermittent pneumatic compression. The primary efficacy outcome was venous thromboembolism up to day 10. The main safety outcomes were major bleeding and all-cause mortality. Follow-up lasted 32 days. RESULTS: Of the 1309 patients randomized, 842 (64.3%) were evaluable for efficacy. The venous thromboembolism rate was 1.7% (7/424) in the fondaparinux-treated patients and 5.3% (22/418) in the placebo-treated patients (odds ratio reduction 69.8%; 95% confidence interval 27.9-87.3; P = 0.004). Fondaparinux significantly reduced the proximal deep vein thrombosis rate from 1.7% (7/417) to 0.2% (1/424; P = 0.037). Major bleeds occurred in 1.6% (10/635) and 0.2% (1/650) of fondaparinux-treated and placebo-treated patients, respectively (P = 0.006), none being fatal or involving a critical organ. By day 32, eight patients (1.3%) receiving fondaparinux and five (0.8%) receiving placebo had died. CONCLUSIONS: In patients undergoing abdominal surgery and receiving intermittent pneumatic compression, fondaparinux 2.5 mg reduced the venous thromboembolism rate by 69.8% as compared to pneumatic compression alone, with a low bleeding risk as compared to placebo.  相似文献   
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