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尼麦角林是一种麦角生物碱衍生物,广泛应用于脑血管病患者认知障碍的治疗。多项临
床前研究显示,尼麦角林对于认知障碍的改善可能与以下因素有关:尼麦角林除能够改善脑循环,
促进神经递质释放外,还具有营养神经及抗氧化等作用。目前的研究认为,尼麦角林能够改善患者
卒中后抑郁相关的情绪障碍以及有效改善血管性痴呆,提高患者的日常生活能力。同时,尼麦角林具
有良好的安全性,目前暂无尼麦角林治疗导致纤维化或麦角中毒的研究报道。本文就尼麦角林在神
经系统的作用机制、临床疗效及安全性进行综述,以期为临床应用提供参考。 相似文献
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Mao-Sheng Ran Meng-Ze Xiang Jie Li Jian Huang Eric Yu-Hai Chen Cecilia Lai-Wan Chan Yeates Conwell 《Archives of Suicide Research》2007,11(1):119-127
The aim of this study was to compare the demographic and clinical characteristics of individuals with affective disorders who had attempted suicide at some time in their lives and those who had not made a suicide attempt. In a Chinese rural community, individuals with suicide attempt (N = 30) and those without suicide attempt (N = 166) were assessed with Present State Examination (PSE). Attempters had a significantly higher level of family economic status, higher rate of lifetime depressed mood and hopelessness, and delusions than nonattempters. The logistic regression models also indicated that depressed mood and hopelessness were the most important predictors of suicide attempts. No significant difference in treatment condition was found between attempters and non-attempters. Early identification and interventions focusing on reducing depressed mood, hopelessness, and controlling psychotic symptoms may be helpful in reducing the risk of suicide attempts among individuals with affective disorders residing in the community. 相似文献
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Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
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Ying-Ying Huang Aaron C.-H. Chen James D. Carroll Michael R. Hamblin 《Dose-response》2009,7(4):358-383
The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response. 相似文献