Patient-controlled epidural analgesia: demand dosing

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.     

Pharmacokinetics and metabolism of β-2′-deoxythioguanosine and 6-thioguanine in man

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 (t_1/2) of 14 min and a terminal t_1/2 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 t_1/2 was 40 min while the terminal phase t_1/2 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     

Tumorigenicity of 7, 12-dimethylbenz[a]anthracene, its hydroxy-methylated derivatives and selected dihydrodiols in the newborn mouse

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.     

Sex differences in inferior parietal lobule volume in schizophrenia

OBJECTIVE: The inferior parietal lobule is a heteromodal association cortical region that has been implicated in the pathophysiology of schizophrenia. Inferior parietal lobule gray matter volumes have been shown to differ between healthy male and female subjects, with male subjects having larger left volumes. The authors sought to determine whether these volumetric sex differences also exist in patients with schizophrenia. METHOD: The authors used magnetic resonance imaging to measure inferior parietal lobule volumes of 15 pairs of male and female schizophrenic subjects who were individually matched to each other and to 15 pairs of healthy male and female subjects. RESULTS: Male schizophrenic patients exhibited a reversal of the normal left-greater-than-right male asymmetry in this region and had left inferior parietal lobule gray matter volumes that were significantly smaller than those of healthy male subjects. Female schizophrenic patients did not differ significantly from healthy female subjects in left or right inferior parietal lobule volume or in asymmetry. CONCLUSIONS: This study provides further evidence of brain morphology sex differences in schizophrenia that possibly contribute to the differential clinical disease expression in men and women.     

Adult bacterial meningitis in Southern Taiwan: epidemiologic trend and prognostic factors

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.     

心律平治疗室性及室上性心律失常疗效分析

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。     

神阙穴贴药对原发性骨质疏松症超声穿透速度的影响

目的：观察神阙穴贴补血益精透皮贴剂，对原发性骨质疏松症超声穿透速度（SOS）的影响。方法：选择原发性骨质疏松症患者130例。分4组治疗。即补血益精透皮贴剂组（A组），西药对照组（B组），补血益精药丸组（C组），空白对照组（D组）。结果：补血益精透皮贴剂组能显著提高超声穿透速度。结论：补血益精透皮贴剂组与补血益精药丸组和西药对照组对原发性骨质疏松症的调整作用基本一致。为治疗原发性骨质疏松症提供了一种新的方法。     

面口合谷收的形态学基础

目的：探讨合谷穴与口面部联系的形态学基础。方法：采用荧光素单标记和双标记法，将荧光素碘化丙啶（PI）和双苯甲亚胺（Bb)分别注入“合谷”穴区和“四白”穴区，取同侧脊神经节颈1-颈8，胸1-胸2，颈上，中，下交感节及三叉神经半月节，荧光显微镜下观察计数。结果：在脊神经节颈5-颈8观察到大量PI单标记细胞，主要分布于颈6-颈7，在三叉神经半月节也可见大量Bb单标记细胞，另外在三叉神经半月节可见少量PI-Bb以标记细胞，占标记细胞的4.5%。结论：三叉神经半月节有向“合谷”穴和“四白”穴的分支投射，这可能是“面口合谷收”的形态学基础。     

迎随是针刺补泻的原则

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     

论中医"藏象"思维模型及其对系统复杂性研究的意义

构成人体子系统间的关联关系复杂 ,并且人体能不断与外界进行物质、能量、信息的交换 ,因此人体是一个开放的复杂巨系统[1] 。中医以其独特的研究方法和认知模式 ,能够有效地分析人体复杂的生命现象和维护人体的健康。本文认为思维模型的运用 ,是中医研究人体的基本手段和方法。思维模型不是利用物质实物做模型 ,而是在人们的思维中对认识对象的一种纯化、简化的映象 ,它是抽象的 ,是思维形式的模拟物 ,需要用思维把握[2 ] 。本文就中医“藏象”思维模型的建构过程、特点及其对人体系统复杂性研究的意义 ,探讨如下。1　“藏象”是中医认识人…