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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。  相似文献   
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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。  相似文献   
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It is commonly assumed that persons who hold abortions to be generally impermissible must, for the same reasons, be opposed to embryonic stem cell research [ESR]. Yet a settled position against abortion does not necessarily direct one to reject that research. The difference in potentiality between the embryos used in ESR and embryos discussed in the abortion debate can make ESR acceptable even if one holds that abortion is impermissible. With regard to their potentiality, in vitro embryos are here argued to be more morally similar to clonable somatic cells than they are to in vivo embryos. This creates an important moral distinction between embryos in vivo and in vitro. Attempts to refute this moral distinction, raised in the recent debate in this journal between Alfonso Gómez-Lobo and Mary Mahowald, are also addressed.  相似文献   
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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。  相似文献   
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Cell phone use while driving (CPWD) has been shown to significantly reduce driver safety. This is a particular concern among young drivers who possess less driving experience and tend to engage in high rates of cell phone use. The present study identified psychological predictors of near accidents related to CPWD among a sample of 385 college student drivers. Participants answered a series of questions regarding their use of a cell phone while driving and completed measures of mindfulness, polychronicity, and intrusive thinking. Students who reported talking on their phone or texting more frequently while driving reported a higher incidence of near accidents related to each behavior. However, after controlling for CPWD, multiple regression analysis indicated that those who reported experiencing more cell phone-related intrusive thoughts also experienced more near accidents. Furthermore, two facets of mindfulness—acting with awareness and nonjudging of inner experience—were negatively associated with near accidents. These findings suggest that individuals who are more aware of the present moment and accepting of their affective responses may better regulate their attention while using a cell phone behind the wheel.  相似文献   
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This study investigates the acquisition of integrated object manipulation and categorization abilities through a series of experiments in which human adults and artificial agents were asked to learn to manipulate two‐dimensional objects that varied in shape, color, weight, and color intensity. The analysis of the obtained results and the comparison of the behavior displayed by human and artificial agents allowed us to identify the key role played by features affecting the agent/environment interaction, the relation between category and action development, and the role of cognitive biases originating from previous knowledge.  相似文献   
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ObjectivesThe present study aimed to investigate the difference in fundamental cognitive processing and neural oscillations between badminton players and sedentary controls.DesignA cross-sectional design was adopted to address this issue.MethodsWe compared time-frequency electroencephalographic (EEG) activity from collegiate female badminton players (n = 12, aged 20.58 ± 2.75 years) and age-and gender-matched sedentary non-athletic controls (n = 13, aged 19.08 ± 2.10 years) when they performed a task that involves visuo-spatial attention and working memory.ResultsWe observed that players responded faster than controls on the task without suffering any increase in error responses. Correspondingly, the players, relative to controls, exhibited higher task-related modulations in beta power in the attention condition as well as in theta and beta power in the working memory condition. Notably, the behavior-EEG correlations revealed that better attention performance is associated with lower beta power, while greater working memory is related to higher theta power.ConclusionsOur results shed light on the mechanisms of athletic superiority in fundamental cognitive functioning: the higher theta synchronization points to a greater engagement of attention, whereas the higher beta desynchronization supports the contribution of processing speed (or motor-related processing) to better performance in athletes. This study extends current understanding by suggesting that enhanced neurocognitive function seen in athletes may transfer to fundamental tasks, giving insight into the generalizability of sport experience to neurocognitive functioning.  相似文献   
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干细胞研究取得了里程碑式的进展,在临床疾病的预防和治疗中具有广阔的应用前景,这些研究成果凝聚了各国研究人员的集体智慧,多向立体思维方法得到了充分体现。  相似文献   
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通过检索国内外6个文献数据库以获取发表于2010年1月~2020年7月研究相关的文献,并对干细胞来源的生物材料采集的供者健康风险进行了系统性综述。50篇相关文献分析显示,在许多情况下,生物材料采集可使供者承受健康风险,包括麻醉、粒细胞集落刺激因子或促排卵药物使用、中心静脉导管放置、穿刺等带来的风险。此外,生物材料采集还可影响供者的心理健康。根据上述发现,建议干细胞来源的生物材料采集需要严格的伦理管控,以保障生物材料供者的健康权益。

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