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51.
52.
Smoking and raven IQ 总被引:1,自引:0,他引:1
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks. 相似文献
53.
R. Schall F. O. Müller H. K. L. Hundt L. Duursema G. Groenewoud M. Van Dyk A. M. C. Van Schalkwyk 《Biopharmaceutics & drug disposition》1994,15(6):493-503
Four controlled-release nifedipine products were investigated in two clinical studies. In study 1, 22 healthy male volunteers took part in an open, multiple-dose, randomized, crossover study to determine the relative bioavailablity of two 10 mg controlled-release nifedipine tablet (Adalat® Retard, Bayer), administered 12 hourly, and one 20 mg controlled-release nifedipine tablet (Adalat® Retard, Bayer) administered 12 hourly. In study 2, 24 healthy male volunteers took part in an open, multiple-dose, randomized, three-period, crossover study to determine the relative bioavailability of (i) two 30 mg nifedipine gastro-intestinal therapeutic system (GITS) tablets (Adalat® XL, Bayer) administered once daily; (ii) one 60 mg nifedipine GITS tablet (Adalat® XL, Bayer) administered once daily; and (iii) one 20 mg plus one 10 mg nifedipine controlled-release tablet (Adalat® Retard, Bayer), administered 12 hourly. In both studies detailed pharmacokinetic data, in particular with respect to the controlled-release characteristics of the different formulations, were collected. Results of both studies indicate that all nifedipine products investigated are bioequivalent with respect to the extent of absorption of nifedipine. The nifedipine GITS products (Adalat® XL) have better controlled-release properties than the Adalat® Retard product, and are suitable for once-a-day administration. 相似文献
54.
系统地介绍了军队卫生系统计算机应用的概况,总结了军队卫生系统自动化建设的主要经验,并提出了加强军队卫生系统计算机应用的设想。 相似文献
55.
Neurotoxic effects of flunarizine (Fz), a selective calcium channel blocker, on the nigrostriatal dopamine system was investigated. Systemic injections of Fz to mice resulted in a transient loss of tyrosine hydroxylase (TH) immunoreactive nigrostriatal neurons without cell loss. TH immunoreactivity in these neurons was greatly reduced as rapidly as one day after drug administration (regardless of dosage used) and thereafter recovered in both dose- and time-dependent manners. Such a novel neurotoxic action of Fz may constitute a morphological substrate for reversible drug-induced parkinsonian signs described in recent clinical case reports. 相似文献
56.
建立了小鼠脾脏、胸腺细胞体外转化微量培养系统,确定了最佳实验条件.点蜡法充CO_2,简便易行,效果好.RPMI-1640培养基内补充胎牛血清,其浓度确定为在脾细胞培养为10%,在胸腺细胞培养为20%.脾细胞培养最适细胞密度为2~5×10~6/ml,Con A最适量为2~4μg/培养;胸腺细胞培养细胞最适密度为1×10~7/ml,Con A最适量为2~4μg/培养.两种已知免疫活性的药物在脾细胞培养体系有明确肯定的反应. 相似文献
57.
The blood–brain barrier (BBB) is an immense neurovascular interface. In neurodegenerative, ischemic, and traumatic disorders of the central nervous system (CNS), the BBB may hinder the delivery of many therapeutic peptides and proteins to the brain and spinal cord. Fortunately, the mistaken dogma that peptides and proteins do not cross the BBB has been corrected during the past two decades by the accumulating evidence that peptides and proteins in the periphery exert potent effects in the CNS. Not only can peptides and proteins serve as carriers for selective therapeutic agents, but they themselves may directly cross the BBB after delivery into the bloodstream. Their passage may be mediated by simple diffusion or specific transport, both of which can be affected by interactions in the blood compartment (outside the BBB) and within the endothelial cells (at the BBB level). Although the majority of current delivery strategies focuses on modification of the molecule to be delivered, understanding the mechanisms of transport will eventually facilitate regulation of the BBB directly. We review the different aspects of interactions and discuss recent advances in the cell biology of peptide/protein transport across the BBB. Better understanding of the nature and regulation of the transport systems at the BBB will provide a new direction to enhance the interactions of peripheral peptides and proteins with the CNS. 相似文献
58.
多层螺旋CT尿路造影在尿路梗阻性疾病中的临床应用 总被引:10,自引:1,他引:9
目的探讨多层螺旋CT尿路造影在泌尿系梗阻性疾病诊断中的应用价值。方法对48例泌尿系统梗阻性疾病者,分别进行多层螺旋CT平扫及多时相期CT增强扫描。对增强后各期图像进行相关处理,以不同的三维重建方式获得CTA、CTU影像。所有病例均经临床及手术证实。结果48例中肾脏及输尿管先天畸形者15例;输尿管阴性结石致肾盂输尿管积水者4例;泌尿系炎症者5例;肾及输尿管、膀胱结核6例;外源性压迫导致肾盂及输尿管积水者8例;泌尿系肿瘤者10例。结论多层螺旋CT泌尿系造影对尿路梗阻性疾病的诊断具有很高的应用价值。 相似文献
59.
Anesthesia safety for endoscopic laryngeal laser surgery has been a major limiting factor for laser applications in the larynx and the hypopharynx. Several anesthesia techniques have been proposed and each technique appears to have its own limitations. This paper will deal with the distinct advantages offered by the malleable copper tube which is used for delivery of the open Venturi system anesthesia for endoscopic laser surgery. A retrospective study of 100 patients who have undergone this modality of anesthesia at our institution will be presented. Our conclusion from this study shows clearly the superiority of the copper tube over the conventional aluminium-foil-wrapped endotracheal tube in safety and the exposure of the larynx during surgery. 相似文献
60.
目的本文以医院信息系统(hispitalinformation system,HIS)系统实施的一般规律为例,讨论了HIS系统实施的一般规律,深入探讨了范围变更产生的原因、接受依据以及管理技术,对于HIS系统实施中最常发生的范围变更管理提出了对策,以使医院业务与HIS软件系统有机会结合在一起,真正实现医院业务信息化的目标。方法文章认为,系统范围变更管理应贯穿于系统实施过程的始终,每一项需求变更都应分析其产生的原因、对医院业务的影响和对系统实施的影响,以确定是否接受范围变更。结果当决定接受或拒绝范围变更申请时,信息科都应与提供产品公司的实施工程师沟通。结论在范围变更管理中,要充分使用好文档模板,并制定出规范的范围变更管理流程,以提高范围变更管理效率。 相似文献