The role of vital exhaustion in predicting the recurrence of vascular events: A longitudinal study

Background/objective

The aim of this study was to examine the role of vital exhaustion in predicting the recurrence of vascular events.

On maximal intermediate predicate constructive logics

We extend to the predicate frame a previous characterization of the maximal intermediate propositional constructive logics. This provides a technique to get maximal intermediate predicate constructive logics starting from suitable sets of classically valid predicate formulae we call maximal nonstandard predicate constructive logics. As an example of this technique, we exhibit two maximal intermediate predicate constructive logics, yet leaving open the problem of stating whether the two logics are distinct. Further properties of these logics will be also investigated.Presented by H. Ono     

Fighting experiences and natural killer cell activity in male laboratory mice

There is currently much interest in the potential impact of psychological factors on immune responses. An attempt was made to assess the effects of dominant/subordinate polarity in male mice on the cytotoxic activities of their natural-killer (NK) cells. On the basis of repeated agonistic encounters, categories of subordinate and dominat animals were selected. These animals were compared with manipulated controls (introduced to a novel test cage without an opponent on each occasion) and undisturbed controls (who remained in isolation without manipulation). In terms of NK activity, immunosuppression was observed in both dominant and subordinate categories when compared to undisturbed controls. There were, however, no differences between the fighting exposed subjects and the manipulated controls, suggesting that stress accounts for any changes. © 1994 Wiley-Liss, Inc.     

Bilateral Transcranial Direct Stimulation Over the Primary Motor Cortex Alters Motor Modularity of Multiple Muscles

Abstract

Transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) has been demonstrated to modulate the motor performance of both healthy individuals and patients with neuromuscular disorders. However, the effect of tDCS on motor control of multiple muscles, which is a prerequisite to change in motor performance, is currently unknown. Using dimensionality reduction analysis, we investigated whether bilateral tDCS over M1 modulates the coordinated activity of 12 muscles. Fifteen healthy men participated in this randomized, double-blind crossover study. Each participant received a 20-min sham and 2-mA stimulation bilaterally over M1 (anode on the right M1 and cathode on the left M1), with a minimum washout period of 4?days. Muscle activation and end-point kinematics were evaluated during a task where participants reached out to a marked target with non-dominant hand as fast as possible, before and immediately after tDCS application. We found decreased similarity in motor modularity and significant changes in muscle activation in a specific motor module, particularly when reaching out to a target placed within arm’s length and improved smoothness index of movement only following 2-mA stimulation. These findings indicate that clinicians and researchers need to consider the simultaneous effect of bilateral tDCS over M1 on multiple muscles when they establish tDCS protocol to change in motor performance of patients with neuromuscular deficits.     

关于胚胎干细胞研究的一场伦理之争

关于“人兔细胞融合”的伦理之争,主要围绕“人兔细胞融合”实验是否违背伦理,要不要经过知情同意,以及科学技术与伦理道德的关系等问题而进行。这场讨论是正常的,健康的,有益的,倘能加以认真总结,将有助于推进学术争鸣。     

应用分子靶向治疗的时机选择

分子靶向药物的出现显示出肿瘤治疗传统模式的重要进展。与传统放疗、化疗相比,分子靶向治疗因其特异性高、不良反应轻微,在恶性肿瘤个体化治疗中扮演重要角色。十五年来,分子靶向药物的出现,给肿瘤的治疗模式带来重大改变,也给临床医生带来新的挑战。准确把握分子靶向药物应用时机,获得最大临床效果,已成为肿瘤治疗领域关注热点。本文就非小细胞肺癌、消化系统肿瘤、乳腺癌、肾癌治疗中分子靶向药物如何选择应用时机进行阐述。     

CXCR4和CXCR7在甲状腺癌中的表达及病理意义

研究甲状腺癌组织中趋化因子4受体（CXCR4）和趋化因子7受体（CXCR7）的表达情况及临床病理意义。应用免疫组织化学PV-6000法及Westernblot法检测CXCR4与CXCR7在甲状腺癌中的表达。二者在甲状腺癌与甲状腺良性疾病组织的差异均具有统计学意义（P〈0．05）,在甲状腺癌中表达仅与淋巴结转移有关（P〈0．05）,CXCR4与CXCR7之间呈正相关。Westernblot结果提示二者在甲状腺癌中的表达率高于癌旁及甲状腺腺瘤。CXCR4和CXCR7的表达水平与淋巴结转移相关,可作为甲状腺癌预后的判断指标。     

非小细胞肺癌 EG FR 基因突变检测与临床意义

采用荧光PCR法对199例晚期非小细胞肺癌（NSCLC ）组织进行表皮生长因子受体（EGFR ）基因突变检测,分析EGFR基因突变的分布特征及其与临床病理特征的相关性。结果显示56例（28．1％）存在EGFR基因突变,其中27例（13．6％）为外显子19突变,25例（12．6％）为外显子21突变,2例为外显子18突变,1例外显子20突变,1例外显子18和20的共突变。另外,除广东及安徽省铜陵市外,辽宁地区NSCLC患者EGFR基因突变率及主要突变类型与其他地区相符,常见于外显子19、21突变,其中腺癌、不吸烟患者突变率更高,更适宜EGFR-TKI靶向治疗。     

我们应该“创造生命”吗？

人造细胞是现代生物科学技术中的热点问题之一,由人造细胞及其衍生出来人造生命的伦理问题也备受关注,关于是否应该继续研究人造生命,支持者和反对者之间各执其词。以克莱格·文特“创造人造细胞”事件为切入点,回顾了人造生命的历史,简要介绍人造细胞的产生过程,分析人造细胞的正面和负面影响;同时提出马克思主义哲学可以为医学伦理问题的研究提供不同的维度与角度,让人们对人造细胞产生的道德问题做出更全面的判断。     

Rate of Torque Development and Feedforward Control of the Hip and Knee Extensors: Gender Differences

The purpose of this study was to determine whether women demonstrate decreased rate of torque development (RTD) of the hip and knee extensors and altered onset timing of the vastus lateralis and gluteus maximus during a drop-jump task when compared with men. On average, women demonstrated significantly lower normalized RTD of the hip extensors (women: 11.6 ± 1.3 MVT.s^?1, men: 13.1 ± 0.9 MVT.s^?1; p ≤ .01); however, there was no significant difference in knee extensor RTD. Women also demonstrated significantly earlier activation of their vastus lateralis (women: 206.0 ± 130.6 ms, men: 80.9 ± 69.6 ms; p ≤ .01) and gluteus maximus (women: 85.7 ± 58.6 ms, men: 54.5 ± 35.4 ms; p = .02). In both men and women, there was a significant negative correlation between the hip extensor RTD and the vastus lateralis electromyographic onset time (men: r = –.386, p = .046; women: r = –.531, p = .008). The study findings suggest that women may utilize a feedforward control strategy in which they activate their knee extensors earlier than men to compensate for deficits in hip extensor RTD. The impaired capacity to rapidly stabilize the hip and knee joints during dynamic maneuvers may contribute to the increased risk of anterior cruciate ligament injury observed in women.