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Veena Kumari Jeffrey A. Gray Philip J. Corr Owen F. Mulligan Paul A. Cotter Stuart A. Checkley 《Psychopharmacology》1997,129(3):271-276
The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using
a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning.
The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase
in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given
haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation
of abnormalities of procedural learning processes in schizophrenia.
Received: 28 June 1996/Final version: 2 October 1996 相似文献
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[目的]应用固体滴定技术监测羟基磷灰石(Hydroxyaptite,HA)的溶解平衡过程,观察组织液生理浓度CO2对羟基磷灰石溶解度的影响.[方法]在恒温水浴系统中以HA为固体滴定物.测试液为KCl溶液(0.1 mol/L),并引入恒定分压的CO2(占空气体积比为3.5%±0.1%).半导体二极管激光为发射光源,散射光源探测器用于监测HA的溶解平衡过程并判断超越溶解平衡点所出现的沉淀(合共17次滴定终点).固体滴定总量用于代表溶解度等温线上的数据点.[结果]引入恒定分压CO2后测定的HA在KCl溶液中的溶解度高于其在KCl溶液中所得50倍以上.[结论]固体滴定技术利于监测HA的溶解平衡过程.溶液体系中CO2增加HA的溶解度.推测该现象与CO2-3形成的复合物密切相关. 相似文献
4.
Biostatisticians have frequently uncritically accepted the measurements provided by their medical colleagues engaged in clinical research. Such measures often involve considerable loss of information. Particularly, unfortunate is the widespread use of the so‐called ‘responder analysis’, which may involve not only a loss of information through dichotomization, but also extravagant and unjustified causal inference regarding individual treatment effects at the patient level, and, increasingly, the use of the so‐called number needed to treat scale of measurement. Other problems involve inefficient use of baseline measurements, the use of covariates measured after the start of treatment, the interpretation of titrations and composite response measures. Many of these bad practices are becoming enshrined in the regulatory guidance to the pharmaceutical industry. We consider the losses involved in inappropriate measures and suggest that statisticians should pay more attention to this aspect of their work. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
电位滴定法测定胰激肽释放酶活力测试条件探讨 总被引:8,自引:0,他引:8
本文用FIP推荐的方法,以具有国际单位的参照品为标样,滴定液为0.01mol/LNaOH标准溶液,考查了以BAEE为底物的电位滴定法测定胰激肽释放酶活力的实验条件,通过正交试验得出直观和方差分析的结果,依据酶活力单位高、SD和RSD%较小的原则,求出酶活力测定的最适条件是:酶反应温度为25℃;缓冲液为0.0015mol/LNa2B4O7-0.25mol/LNaCL-2×10(-4)mol/LEDTA,pH为8.00;反应液中酶浓度为0.48IU/ml;底物浓度为5×10(-3)mol/L;胰蛋白酶抑制剂浓度为125μg/ml。胰激肽释放酶活力测定的实验数据的相对标准偏差小于5%。 相似文献
6.
The effect of lithium on slow wave sleep (SWS) was studied in ten normal male volunteers using home based cassette sleep recording and automatic sleep stage analysis. Lithium increased SWS, an effect consisten with a reduction in brain 5-HT2 receptor function. 相似文献
7.
野菊花中刺槐甙的库伦滴定法 总被引:2,自引:0,他引:2
野菊花Chrysanthemum indicum L.是一种常用中草药,对防治流行性脑脊髓膜炎、流感、高血压、肝炎、痢疾、痈疖疗疮有一定作用。最近还报道野菊花栓剂可用于治疗前列腺炎等症。野菊花的化学成分,据报道含有黄酮类化合物,已知的有刺槐甙(acaciin),水解后得刺槐素(acacetin),分子结构式为 相似文献
8.
Titration of Power Output During Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia 总被引:3,自引:0,他引:3
JONATHAN J. LANGBERG MARK HARVEY HUGH CALKINS RAFEL EL-ATASSI STEVEN J. KALBELEISGH FRED MORADY 《Pacing and clinical electrophysiology : PACE》1993,16(3):465-470
Radiofrequency lesions in the anterior, superior aspect of the tricuspid annulus result in selective elimination of fast pathway function in patients with typical atrioventricular (AV) nodal reentry tachycardia. This technique is simple and effective, but has been associated with a significant risk of inadvertent complete AV block. The purpose of this study was to compare the safety and effectiveness of two different techniques for radiofrequency catheter ablation of the fast AV nodal pathway. Initially, a fixed power output was used at each target site. This method was compared retrospectively to a newer technique where power output was gradually incremented at each site. Radiofrequency power was initially applied at 10 watts for 10–15 seconds. If no junctional ectopy or a change in PR intervoi was seen, power output was incremented by 2 to 4 watts every 10 to 15 seconds up to a maximum of 30 watts. Thirty seven of 38 (96%) patients treated using this incremental power output were cured of their AV nodal reentry tachycardia. None of these patients developed inadvertent complete AV block. In contrast, 92% of historic controls treated with a fixed power output between 20 and 30 watts achieved a primary success and nine of these 89 (10%) historic controls developed inadvertent complete AV block (P = 0.04). There was no difference in the amplitudes of atrial, His, or ventricular electrograms at the effective sites between the two groups. Conclusions: (1) the anterior approach to radiofrequency catheter ablation of typical AV nodal reentry is associated with a significant risk of inadvertent complete AV block if a fixed power output is used; (2) starting at low power and gradually incrementing the output during radiofrequency energy application reduces the risk of complete AV block; (3) this incremental technique does not compromise efficacy. 相似文献
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10.
本文设计的8模型血压自适应控制系统,试用于造成失血休克模型的家兔的血压自控治疗,22只休克家兔中18只能控制血压于预置水平。根据血压控制期间药物输注速率变化规律,可将22只家兔分为三类,剂量上升型、剂量下降型和迟钝型。实验表明多模型血压自适应控制系统应用于失血性休克家兔的血压控制治疗是可行的,能做到剂量个体化,按需给药。在血压控制期间显示的药物输注速率变化能在一定程度上反映机体休克状况,有可能为及 相似文献