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991.
Patient-controlled epidural analgesia: demand dosing 总被引:17,自引:0,他引:17
A double-blind, placebo-controlled study was designed to compare the efficacy of demand-dose patient-controlled epidural analgesia (PCEA) with continuous epidural infusion (CEI) for treatment of pain during labor and delivery. Forty patients were randomized to receive 0.125% bupivacaine with fentanyl (2 micrograms/mL) through CEI at 12 mL/h or through demand-dose PCEA. Patients using PCEA could demand 3 mL every 10 min without restriction. Analgesia in both groups was comparable. However, there was a significant reduction in total bupivacaine consumption (in milligrams) associated with the use of PCEA (mean +/- SEM: CEI = 76.1 +/- 8.5 mg; PCEA = 42.2 +/- 5.9 mg; 45% reduction). The hourly bupivacaine consumption during the first (CEI = 15.8 +/- 0.6 mg/h; PCEA = 8.8 +/- 1.1 mg/h) and second (CEI = 17.2 +/- 1.2 mg/h; PCEA = 6.8 +/- 1.2 mg/h) stages of labor was also reduced. Overall, this represented a 47% "sparing" of bupivacaine use per hour with PCEA. Similar reductions occurred in the use of fentanyl. The reductions in analgesic requirement, however, were not associated with a reduction in the degree of motor blockade or in the cephalad extent of sensory blockade. A significant dose-sparing effect was associated with the use of demand-dose PCEA as compared with standard CEI for analgesia during labor and delivery. 相似文献
992.
Katherine Lu John A. Benvenuto Gerald P. Bodey Jeffrey A. Gottlieb Michael G. Rosenblum Ti Li Loo 《Cancer chemotherapy and pharmacology》1982,8(1):119-123
Summary Resistance to the antileukemic agent 6-thioguanine (TG) inevitably develops in animal tumors. However, a new agent, -2-deoxythioguanosine (-TGdR) can overcome TG resistance in animal tumor models and is therefore of potential clinical use. The pharmacokinetics of radiolabeled TG were compared with those of -TGdR in patients with cancer after intravenous administration. [35S]--TGdR (5.4 mg/kg, 200 mg/m2, 200 Ci total) was administered to five patients; the radiolabel in the plasma declined with an initial half-life (t1/2) of 14 min and a terminal t1/2 of 19.3 h. Within 24 h, 65% of the radiolabel was excreted in the urine. In contrast, after administration of [35S]-6-TG (3.4 mg/kg, 125 mg/m2, 200 Ci total) the average initial t1/2 was 40 min while the terminal phase t1/2 was 28.9 h. Urinary excretion of the radiolabel was 75% of the dose 24 h after administration. Both thiopurines were rapidly and extensively degraded and excreted as 6-thioxanthine, inorganic sulfate, S-methyl-6 thioxanthine, and 6-thiouric acid in addition to other products. Small amounts of unchanged drug were also excreted. These studies suggest that -TGdR is merely a latent form of TG.Deceased, to whose memory this paper is dedicated 相似文献
993.
Wisloclki Peter G.; Juliana M. Margaret; MacDonald James S.; Chou Ming W.; Yang Shen K.; Lu Anthony Y. H. 《Carcinogenesis》1981,2(6):511-514
The newborn mouse lung adenoma model has been shown to be asensitive test for studying the tumor-igenicity of bay regiondiol epoxides and their precursor dihydrodiols. When a totaldose of 28 nmol of 7, 12-dimethylbenz[a]anthracene (DMBA) orits derivatives was injected i.p. into the preweaning mice,it was found that the 3, 4-dihydrodiols of both DMBA and 7-hy-droxymethyl-12-methylbenz[a]anthracenecaused 13.3 and 4.1 times more lung adenomas than DMBA, respectively.The mice treated with the 5, 6- and 8, 9-dihydro-diols of DMBA,7-hydroxymethyl-12-methylbenz[a]-anthracene and its 5, 6- 8,9-and 10,11-dihydrodiols, 7-methyl-12-hydroxymethylbenz[a]an-thraceneand 7,12-dihydroxymethylbenz[a]anthracene developed a levelof lung adenomas/mouse less than Mold higher than that foundin the DMSO-treated control group. Liver tumors also developedin some of the mice. The percentage of mice with liver tumorsalso indicated that the 3, 4-dihydrodiols of both DMBA and 7-hydroxymethyl-12-methylbenz[a]anthracenewere more tumorigenic than DMBA itself. These data indicatethat the 3, 4-dihydrodiols of both DMBA and its 7-hydroxymethylderivative may be proximate carcinogenic metabolites of DMBAin the newborn mouse. 相似文献
994.
Adult bacterial meningitis in Southern Taiwan: epidemiologic trend and prognostic factors 总被引:5,自引:0,他引:5
In two investigative phases over a 13.5-year study period (January 1986-June 1999), 202 adult patients with culture-proven bacterial meningitis were enrolled in this study. In order to determine the epidemiologic trend, prognostic factors and therapeutic results for this disease. Klebsiella pneumoniae (K. pneumoniae), Pseudomonas aeruginosa, and Streptococcus pneumoniae were the three most commonly revealed pathogens, accounting for about 48% of the episodes. Although there was a change in relative frequency for the pathogens, K. pneumoniae remained the most prevalent during the two periods studied (January 1986-December 1992 and January 1993-June 1999). Multiantibiotic resistant strains have been in evidence since their appearance in 1994, with most of our patients acquiring their infection nosocomially. The overall mortality rates during the two periods were 40% and 34%, respectively. In stepwise logistic regression analysis, only initial conscious level, appropriate antibiotic therapy and septic shock were independently associated with mortality, after adjustment for other potentially confounding factors. Initial empirical antibiotics with both third-generation cephalosporin and penicillin G, should be considered for the majority of meningitis cases resulting from infection with Gram-negative bacilli and streptococcal species. Besides the evolution of newer pathogens, there has been increasing incidence for nosocomially acquired bacterial meningitis for patients postneurosurgery, with the emergence of resistant strains presenting a therapeutic challenge in recent years. Vancomycin and imipenem/cilastatin should be considered as the initial empirical antibiotics of choice for the treatment of this special group of patients. 相似文献
995.
心律平治疗室性及室上性心律失常疗效分析 总被引:1,自引:0,他引:1
目的 观察心律平治疗室性及室上性心律失常的疗效及副作用。方法 对于107例经心电图及临床确诊的室性及室上性心律失常患者,按口服心律平剂量不同分为:300mg/d组(33例)、450mg/d组(66例)、600mg/d组(8例)三组,10d为1个疗程;分析心律失常类型、心律平剂量与疗效的关系、副作用及原因。结果 心律平对室性及室上性心律失常总有效率分别为89.6%与79.7%(P>0.05);3种剂量与疗效关系不大(P>0.05);发生副反应19例,占17.8%,无效17例,占15.9%。结论 心律平对室性及室上性心律失常均;有良好治疗作用,较为安全。 相似文献
996.
997.
998.
迎随是针刺补泻的原则 总被引:1,自引:0,他引:1
以《灵枢·九针十二原》《难经·七十二难》等篇为据 ,说明在《内经》《难经》中 ,迎随不是某一具体的针刺补泻手法 ,只是一切针刺补泻法的代称和原则。对于迎随 ,后世大多宗于《难经》 ,发展为深浅迎随、针向迎随、流注盛衰时间迎随、补母泻子迎随等。现代多以针向迎随为补泻 ,但在临床上很少单独用。针向迎随在理论上不符合《灵枢》本义 ,在临床上只能在四肢穴作行气法用 ,没必要作为一种具体的针刺补泻手法存在 相似文献
999.
1000.
针灸抗早孕及引产催产研究进展 总被引:4,自引:3,他引:4
本文对近 5年针灸在抗早孕、引产催产方面的临床和实验研究的情况进行了总结。通过对 1 997年以来国内杂志相关文献进行综述 ,总结出在抗早孕方面 ,针灸主要应用于人流和药流的辅助治疗 ;在引产催产方面 ,针灸的应用与 5年前基本相同 ;在实验研究方面 ,主要是从电生理的角度验证和解释临床现象。针灸具有扩张宫颈、提高人流效果、镇静止痛、减少术中出血量等作用 ;针灸在药流中可加速排囊并提高完全流产率、减少出血、加快转经 ;针灸引产催产有效率较高 ,能促进宫颈成熟、缩短产程、减少产后出血量、减轻疼痛 ;实验研究发现针刺增强药流作用可能是通过调节子宫活动、改善妊娠相关组织血供而实现的 相似文献