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61.
To examine the effects of prolonged (> 24 h) intrathecal catheterization with the use of postoperative analgesia on the incidence of post–dural puncture headache (PDPH), charts of 45 obstetric patients who had accidental dural puncture following attempts at epidural block were reviewed retrospectively. Three groups were identified: Group I (n = 15) patients had a dural puncture on the first attempt at epidural block, but successful epidural block on a repeated attempt; Group II (n=17) patients had a dural puncture with immediate conversion to continuous spinal anaesthesia with catheterization lasting only for the duration of caesarean delivery; Group III (n= 13) patients had an immediate conversion to spinal anaesthesia and received post–caesarean section continuous intrathecal patient–controlled analgesia consisting of fentanyl 5 (ig'ml-1 with bupivacaine 0.25 mg·ml-1 and epinephrine 2 μg·ml-1 with catheterization lasting >24 h. No parturient in group III developed a PDPH. This was substantially lower ( P < 0.009) than the 33% incidence for group I and the 47% incidence for group II. The incidence of a PDPH did not differ between group I and II. Similarly, there was no difference between group I and II with regard to requests for a blood patch. Patients receiving continuous intrathecal analgesia had excellent pain relief, could easily ambulate and none complained of pruritus, nausea, vomiting, sensory loss or weakness. In conclusion, indwelling spinal catheterization > 24 h with continuous intrathecal analgesia following accidental dural puncture in parturients may for some patients be a suitable method for providing PDPH prophylaxis and postoperative analgesia.  相似文献   
62.
A number of factors affecting the stability of propranolol HC1 during electrophoretic control were investigated. It was found that significant degradation of propranolol HC1 and hydrolysis of water occurred when a current of 15 mA was used with platinized electrodes. This degradation was thought to be due to decomposition of propranolol HC1 at the electrodes. Degradation could be significantly reduced by using uncoated platinum electrodes and currents in the range of 0 to 2.5 mA, while still allowing control of drug delivery rates. Electrode reaction processes were found at high ionic strengths and high drug concentrations but were not thought to be associated with drug decomposition.  相似文献   
63.
尼莫地平控释片释放度试验研究   总被引:2,自引:0,他引:2  
本文研究了尼莫地平控释片的释放度试验方法——转篮法,释放介质为含有22%异丙醇的0.1mol·L-1盐酸液;磷酸盐缓冲液(pH5.8)和pH7.2的溶液。含量测定方法:紫外分光光度法,在三种介质中尼莫地平分别在1~30μg·ml-1,10~50μg·ml-1和10~50μg·ml-1的范围内,浓度与吸收度有较好的线性关系。回归方程分别为A=0.615C+0.023(r=0.9999);A=0.0614C+0.012(r=0.9995);A=0.0612C+0.0088(r=0.9999)。平均回收率分别为99.63%,99.98%及100.77%,RSD(%)分别为1.34%,1.59%及1.41%。本方法的体外释放百分率与体内吸收分数有较好的相关性(r=0.991)。  相似文献   
64.
OBJECTIVE: To examine the effect of short-term improvements in glycaemic control on brachial artery endothelial function as a marker of cardiovascular health. METHODS: Persons with Type 2 diabetes who were poorly controlled on oral therapy were randomly assigned to monotherapy with repaglinide or combination therapy with repaglinide plus metformin. Brachial artery flow-mediated vasodilation was assessed by ultrasonography at randomization and following 16 weeks of therapy. The primary outcome was change in brachial artery endothelial function from baseline. Comparison of randomized groups was a secondary aim. RESULTS: Eighty-six participants were randomized, and 83 were followed to study completion. Post occlusion brachial artery vasodilation was 3.74% at baseline and 3.82% following 16 weeks of therapy (P = 0.77). The treatment effect was 0.08% (95% CI: -0.48%, 0.64%). No difference was seen between treatment groups (P = 0.69). Overall, A1C was reduced from 8.3% to 7.0%, with a greater reduction in the combination therapy group (from 8.4% to 6.7%) than in the monotherapy group (from 8.3% to 7.3%, p for difference between groups = 0.01). Statistically significant reductions were observed in fasting glucose, and plasminogen activator inhibitor-1. Statistically significant increases were observed for fasting insulin, uric acid, weight and BMI. CONCLUSIONS: Brachial artery endothelial function was not influenced by short-term improvements in glycaemic control. The CONTROL DM group was successful in lowering A1C. Future research should explore more intensive and longer-lasting improvements in glycaemic control on endothelial function. Some data previously published in abstract form (Diabetes 2001; 50 (Suppl. 2): A217).  相似文献   
65.
目的 系统评价醒脑静注射液治疗缺血性中风急性期的疗效及安全性。方法 集醒脑静注射液治疗缺血性中风急性期随机对照试验文献,筛选合格研究,应用Jadad评分法进行质量评价,运用异质性检验、Meta-分析、漏斗图分析、敏感性分析等方法统计相关数据。结果 项研究符合纳入标准,Jadad评分所有研究得分均低于3分,属低质量文献。Meta-分析结果显示,总有效率比较的相对危险度(RR值)=1.04,99%的可信区间(CI值)为(0.88,1.23)。结论 前尚无充分证据证实醒脑静注射液治疗缺血性中风急性期的疗效及安全性。要进一步验证醒脑静注射液治疗缺血性中风急性期的疗效及安全性,尚需进行设计合理、执行严格、多中心大样本且随访时间足够的随机对照试验。  相似文献   
66.
67.
异丙酚及氯胺酮靶控输注全静脉麻醉临床应用   总被引:4,自引:1,他引:3  
目的 研究异丙酚复合不同镇痛剂量氯胺酮靶控输注全静脉麻醉临床应用的可行性及对血流动力学、麻醉恢复的影响。方法 择期手术患者 80例 ,分别采用异丙酚 (P组 ,n =16)及复合氯胺酮血药浓度 0 2 0mg/L(PK1组 ,n =16) ,0 40mg/L(PK2 组 ,n =16) ,0 60mg/L(PK3 组 ,n =16)和 0 80mg/L(PK4组 ,n =16)全静脉麻醉 ,采用微机控制Graseby 3 5 0 0输液泵靶控输注异丙酚或氯胺酮 ,连接Aspect-A10 0 0型脑电监护仪监测脑电变化 ,观察两组患者血流动力学改变及麻醉恢复情况。结果 单用异丙酚患者随着异丙酚血药浓度升高脑电双频指数 (BIS)值降低 ,呈明显负相关 (P <0 0 5 ) ,氯胺酮血药浓度从 0 2 0mg/L增至 0 80mg/L ,BIS值无明显变化 (P >0 0 5 )。与P组相比 ,PK1,PK2 ,PK3 ,PK4组异丙酚用量减少约 15 %~ 40 % ,PK4组停药至睁眼时间明显延长 ,其余各组无明显差异 (P >0 0 5 )。术中P ,PK1组收缩压、舒张压升高 ,PK2 ,PK3 ,PK4组无明显改变。术后无躁动、不良回忆等并发症。结论 异丙酚复合镇痛剂量的氯胺酮 (0 40~ 0 60mg/L)靶控输注全静脉麻醉具有血流动力学稳定、减少异丙酚用量、无明显术后并发症等优点。  相似文献   
68.
Post-polio syndrome (PPS) is characterized by new muscle weakness, atrophy, fatigue and pain developing several years after the acute polio. Some studies suggest an ongoing inflammation in the spinal cord in these patients. From this perspective, intravenous immunoglobulin (IvIg) could be a therapeutic option. We performed a double-blinded randomized controlled pilot study with 20 patients to investigate the possible clinical effects of IvIg in PPS. Twenty patients were randomized to either IvIg 2 g/kg body weight or placebo. Primary endpoints were changes in pain, fatigue and muscle strength 3 months after treatment. Surrogate endpoints were changes in cerebrospinal fluid (CSF) cytokine levels. Secondary endpoints were pain, fatigue and isometric muscle strength after 6 months. Patients receiving IvIg reported a significant improvement in pain during the first 3 months, but no change was noted for subjective fatigue and muscle strength. CSF levels of tumour necrosis factor- α (TNF- α ) were increased compared with patients with non-inflammatory neurological disorders. In conclusion, in this small pilot study no effect was seen with IvIg treatment on muscle strength and fatigue, however IvIg treated PPS patients reported significantly less pain 3 months after treatment. TNF- α was increased in the CSF from PPS patients. The results are promising, but not conclusive because of the low number of patients studied.  相似文献   
69.
An overview of randomised trials of cholesterol reduction (26 trials, 50,000 patients, net cholesterol reduction ?10%) provides clear evidence of a reduction in the incidence of coronary heart disease (CHD) after just a few years of treatment. Overall, the observed reduction in CHD death (9%± 3) was only half as large as the reduction in non-fatal myocardial infarction (19%±4), although both were statistically significant (2p <0.005). In these trials, 60% of all deaths were from CHD, and since treatment reduced these by about 9%, the expected reduction in total deaths was about 5–6%. This expected reduction falls within the 95% confidence interval of the observed effect of cholesterol reduction on total mortality in these trials. There were small excesses of deaths from cancer and deaths from trauma among patients allocated active treatment. However, in no single trial, nor in the trials collectively, were these increases individually statistically significant. Furthermore, the increases did not appear to be specific to any one agent nor were the increases consistent between trials of the same agent. These observations suggest that the small excesses of noncoronary deaths observed in the cholesterol reduction trials may have occurred by chance. Evidence from ongoing longer-term studies of treatments producing larger cholesterol reductions will be useful in further delineating the effects, if any, of such treatments on non-coronary mortality.  相似文献   
70.
Summary The aim of the study was to use a novel combination of two methods for the simultaneous evaluation of two effects of oral cisapride in 10 diabetic patients with autonomic neuropathy; gastric emptying time was measured by following radio-opaque markers and orocaecal transit time by the sulphasalazine-sulphapridine method. The study was of double-blind, randomized, placebo-controlled, cross-over design.It was possible to evaluate the effect of a prokinetic drug on gastric emptying and orocaecal transit times using these two noninvasive techniques at the same time. Cisapride significantly reduced both the gastric emptying (1.2 h versus 2.1 h) and orocaecal tansit (5.9 h versus 7.7 h) times.  相似文献   
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