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从近视眼的进化史来看,伴随人类生活方式的改变,眼睛对近距离信息摄取的需求膨胀是近视眼形成的终因.在漫长的人类历史中,近视眼获得的每一种益处,都伴随着相应的代价.而达尔文医学关于生物进化的不完美性决定了近视眼的进化适应和代价将长期共存.因此,从治疗模式来看,应该摒弃达尔文医学固有的消极性而考虑生物的整体性和生态性.近视眼的中医和基因治疗正是避免了达尔文医学治疗模式的理论消极性,而且融入了其有关生物进化、遗传与环境统一的部分理念,可能成为近视眼治疗的候选策略. 相似文献
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肥胖是体内脂质过度沉积的一种状态,其不仅可引起糖脂代谢紊乱、胰岛素抵抗,从而继发糖尿病、高血压、冠心病等疾病,而且当脂质水平超过脂肪细胞的储存容量及出现胰岛素抵抗时,血液中游离脂肪酸含量会随之升高,进而可引起脂质在心脏的异位沉积.沉积于心肌细胞的脂质可进一步通过神经酰胺、内质网应激等机制影响心肌细胞的结构和功能,最终导致心力衰竭的发生.但肥胖所致心肌脂毒性具体机制不明,本文就肥胖所致心肌脂毒性可能机制做一综述. 相似文献
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Weiping Hu Baojun Wu Xiaojuan Jia Xinfa Yi Chunyan Duan Winter Meyer James C. Kaufman 《创造性行为杂志》2013,47(1):3-21
The “Learn to Think” (LTT) Intervention Program was developed for raising thinking abilities of primary and secondary school students. It has been implemented in more than 300 schools, and more than 200,000 students took part in the experiment over a 10‐year span. Several longitudinal intervention studies showed that LTT could promote the development of students' thinking ability, learning motivation, and learning strategy as well as raise academic performance in primary schools. This article describes a study of the influence and the delayed effects of LTT on the scientific creativity of secondary school students. One hundred and seven students were selected from a secondary school, 54 of them participated in the LTT every 2 weeks and the rest had not. The intervention lasted 2 years, and the delayed effect was explored half a year after terminating the intervention. The Scientific Creativity Test for Secondary School Students was used four times from pre‐test to delayed post‐test. The results indicated that the LTT did promote the development of scientific creativity of secondary school students, and the effects on the scientific creativity were not necessarily immediate, but tended to be long‐lasting. 相似文献
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We investigated how age of faces and emotion expressed in faces affect young (n=30) and older (n=20) adults’ visual inspection while viewing faces and judging their expressions. Overall, expression identification was better for young than older faces, suggesting that interpreting expressions in young faces is easier than in older faces, even for older participants. Moreover, there were age-group differences in misattributions of expressions, in that young participants were more likely to label disgusted faces as angry, whereas older adults were more likely to label angry faces as disgusted. In addition to effects of emotion expressed in faces, age of faces affected visual inspection of faces: Both young and older participants spent more time looking at own-age than other-age faces, with longer looking at own-age faces predicting better own-age expression identification. Thus, cues used in expression identification may shift as a function of emotion and age of faces, in interaction with age of participants. 相似文献
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本研究选择北京地区幼儿园3岁、4岁、5岁儿童各31、48、33名, 采用单部件意识测验和部件位置及功能意识测验系统探查了学龄前儿童的正字法意识各个层面的发展状况。单部件意识测验包括部件替换、部件缺失和部件旋转三个部分; 部件位置及功能意识测验分为假字和非字两个部分, 而非字又包括两形非字和形声非字。结果发现单部件意识测验中, 5岁组儿童在部件替换水平上的得分显著高于3岁组儿童, 而3岁组与4岁组、4岁组与5岁组儿童之间无显著差异; 部件缺失和部件旋转水平上, 三个年龄段的儿童的得分表现出明显的增长趋势。部件位置及功能意识测验中, 假字得分在三个年龄段之间无显著差异; 非字得分随年龄增长显著提高。这些结果表明, 单部件意识在学前期处于不断发展的阶段, 其中对部件替换的非字的拒绝能力发展较早, 部件缺失和部件旋转非字的拒绝能力发展较晚; 部件位置及功能意识在学前期已经开始发展, 3岁儿童已经具有假字符合正字法规则的认识, 但对非字违反部件位置合法性和功能完整性的认识直到4岁左右才开始萌芽, 5岁还未成熟。 相似文献
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Tae Wook Heo Yi Wang Saswata Bhattacharya Xin Sun Shenyang Hu Long-Qing Chen 《Philosophical Magazine Letters》2013,93(2):110-121
We propose a phase-field model for modeling microstructure evolution during deformation twinning. The order parameters are proportional to the shear strains defined in terms of twin plane orientations and twinning directions. Using a face-centered cubic Al as an example, the deformation energy as a function of shear strain is obtained using first-principle calculations. The gradient energy coefficients are fitted to the twin boundary energies along the twinning planes and to the dislocation core energies along the directions that are perpendicular to the twinning planes. The elastic strain energy of a twinned structure is included using the Khachaturyan's elastic theory. We simulated the twinning process and microstructure evolution under a number of fixed deformations and predicted the twinning plane orientations and microstructures. 相似文献
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