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81.
82.
娄立国 《佳木斯教育学院学报》2014,(2):84-86
比较分析霍桑的三部作品,我们发现一个共性:女主角形象光辉照人,男主角形象晦涩黯淡。信仰,准则,神性,人性,男人,女人,----纵横交织构成了复杂的现实世界,而这个世界却是不平衡的。男性通过压迫女性来彰显自我往往导致得不偿失;阴阳平衡的状态一旦打破,就会产生这样那样的问题。霍桑小说中的很多社会问题都可以归结于社会生态的失衡。在霍桑看似绝望的文学蓝图中隐藏着永恒的希望,这希望便是女性的光辉。 相似文献
83.
合成生物学基于生物、化学、物理、计算、工程等多学科交叉,对生物体以工程化的方式重新设计甚至是从头合成,将克服自然进化的局限,创造超越自然生命能力的合成生物,不仅对探索生命活动基本规律具有重要科学意义,也在工农业生产、环境保护、健康保健等领域具有巨大应用前景。随着合成生物技术发展的日新月异,合成生物的应用范围日益广泛,如何保障合成生物的生物安全性成为一个极其重要并且亟待解决的关键问题。合成生物学研究中大量涉及来自于病毒、致病性细菌和真菌的强毒力基因元器件,且被设计和使用的毒性基因元件和调控元件的数目也从少数几个跃升为几十个、上百个,乃至整个基因组的重新设计和编辑改造。如果缺乏有效管控或被恶意谬用,这些人工合成生物体可能会对生态环境平衡、公共卫生安全乃至国家国防安全造成威胁。因此,在人工设计和改造生物体的过程中,必须建立系统的防范和监控体系,设计有效的方法和技术来阻止人工生命体在野外环境下的复制和增殖、遗传信息的漂移以及阻断其进化出新的环境适应性,做到完全的人工改造生物隔离,达到真正的人工可控生命目标,确保其生物安全性。文章综述了合成生物学的研究进展和合成生物潜在的生物安全性威胁,以及合成生物的生物安全性防控设计策略,并对相关安全政策规章的制定给出了建议。 相似文献
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85.
从教学环境、学生和教师的角度,分析网络语音实验室条件下高校英语教学的优势与问题,并提出有必要对师生进行课程前期实验室使用和维护的培训;学生需要建立科学的网络学习观,培养个性学习策略和方法;教师应强化网络教学的教学形式、评价体系并适应角色转换。 相似文献
86.
Polyethylenimine-cyclodextrin-tegafur (PEI-CyD-tegafur) conjugate was synthesized as a novel multifunctional prodrug of tegafur
for co-delivery of chemotherapeutic agent tegafur and enhanced green fluorescent protein (EGFP) reporter plasmid DNA. Conjugation
of tegafur to PEI-CyD via chemical linkage was characterized by 1H NMR spectrometry and ultraviolet (UV) spectrometry. PEI-CyD-tegafur was able to condense plasmid DNA into complexes of around
150 nm with positive charge at the N/P ratio of 25, in accordance with electron microscopy observation of compact and monodisperse
nanoparticles. The results of in vitro experiments showed enhanced cytotoxicity and considerable transfection efficiency in
B16F10 cell line. Therefore, PEI-CyD-tegafur may have great potential as a co-delivery system with anti-cancer activity and
potential for gene delivery. 相似文献
87.
Moore ML 《The Journal of perinatal education》2002,11(3):43-47
Misoprostol (Cytotec) is a synthetic prostaglandin E1 analogue that was designed for the prevention and treatment of peptic ulcer associated with the use of nonsteroidal anti-inflammatory drugs. In obstetrics, misoprostol has been administered for induction of first and second trimester abortion, for induction of labor in the third trimester, and to control postpartum hemorrhage. None of these uses has been approved by the Food and Drug Administration. Nevertheless, misoprostol is widely used in the United States and throughout the world. Advantages are cited as reduced rate of cesareans, shorter time from induction to birth and, particularly in developing countries, lower cost, oral, vaginal or rectal administration, and stability without refrigeration. Disadvantages are uterine hyperstimulation and, in rare instances, uterine rupture and death. Mothers should be informed of both the risks and the possible benefits of misoprostol. Further research with large samples is necessary to determine whether the risks outweigh any possible benefits. 相似文献
88.
The authors argue that the knowledge work metaphor is the most powerful image of schools for understanding reform. Using themes from the new management literature, such as shared decision making, collegiality, innovation, and experimentation, as additional guides for school improvement, the authors develop a case for systemic reform based on the professionalization of teaching and the integration of theory, research, and practice, Finally, transformational leadership is presented as the key to facilitating systemic reform. 相似文献
89.
鸢尾紫色素的提取与理化性质研究 总被引:2,自引:0,他引:2
以高原鸢尾花为原料,提取紫色色素,并对紫色色素的理化性质进行了研究。结果表明色素具有较好的稳定性,具有一定的开发利用价值。 相似文献
90.
Moore ML 《The Journal of perinatal education》2003,12(2):44-46
IN THIS COLUMN, THE AUTHOR EXAMINES RECENT RESEARCH ON TWO SEPARATE TOPICS: 1) breastfeeding; 2) postpartum length of hospital stay. Recent studies suggest long-term effects of breastfeeding that benefit both mother and infant. Benefits include a reduced risk of breast cancer in breastfeeding mothers and a reduced level of total and LDH cholesterol in adults who were breastfed as infants. Infants of mothers with maternal asthma had lower rates of asthma if the mother breastfed. In a study of women in the United States who planned to breastfeed, those mothers who breastfed exclusively and planned to breastfeed more than three months were more likely to achieve their goals than mothers who planned to combine breast and human-milk substitute feeds and to breastfeed less than three months.In a Canadian study, shortened postpartum stays led to increased re-admission to hospital for mothers with cesarean births. In contrast, in a Massachusetts study, shortened postpartum stays did not lead to an increase in infant visits for urgent care. However, the Massachusetts study did not reflect a decrease in maternity-related costs associated with shortened length of postpartum stay. 相似文献