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51.
Voitova A. A. Dmitrieva M. D. Dymova M. A. Vasileva N. S. Nushtaeva A. A. Richter V. A. Kuligina E. V. 《Russian Journal of Bioorganic Chemistry》2019,45(6):783-792
Russian Journal of Bioorganic Chemistry - Brain tumors are among the most intractable types of malignant neoplasms. Despite advances in the treatment of cancer, in particular, the development of... 相似文献
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为研究杉木在中国的分布特征及其对气候变化的响应模式,本研究基于现有分布记录,应用最大熵(MaxEnt)模型和地理信息系统方法,结合气候、地形等环境要素,预测杉木在当前和未来气候变化下的潜在适生区。结果表明: 影响杉木分布的最主要因素是年平均降水量,在当前气候下,杉木适生区合计面积328万km2,占全国陆地总面积的34.5%,低、中和高适生区分别占18.3%、29.7%与52.0%。在未来气候情景下,杉木生长的适宜性在我国总体上呈上升趋势,适生区面积随气候变化增大,且明显向北扩张,南方湿润亚热带地区形成集中连片高适生区。模型经受试者工作特征曲线检验,训练集平均受试者工作特征曲线下面积为0.91,可信度高。 相似文献
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G M Zakharova T S Belova O V Kamzolkina S V Dmitrieva V N Danilenko 《Antibiotiki i khimioterapii͡a》1988,33(3):217-223
The paper is concerned with development of conditions for cultivation of the erythromycin-producing organism and preparation and maintenance of its stable viable protoplasts. Optimal conditions for the culture growth and protoplasting were developed. Two-stage cultivation of the organism on media PB and S provided dense diffuse or diffuse local growth characterized by low differentiation and higher homogenicity. The incubation time at stage I was 66 hours and that at stage II was not more than 24 hours at respective temperatures. The culture was incubated on a shaker in the presence of glycine at the minimum concentration. The presence of glycine in the medium altered the culture cell walls which was evident from changing of staining by Gram from + to +/- . Treatment of such a culture with lysozyme for 30 minutes provided formation of up to 2.10(9) protoplasts per 1. ml. It is possible to maintain the protoplasts in frozen state at -20 degrees C in medium P for 1 month. Under such storage conditions the titer of the viable protoplasts as compared to the initial one decreased only 2-fold after the one-month storage. 相似文献
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Dmitrieva ES Gel'man VIa Zaĭtseva KA Orlov AM 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2004,54(5):581-591
Cerebral mechanisms of musical abilities were explored in musically gifted children. For this purpose, psychophysiological characteristics of perception of emotional speech information were experimentally studied in samples of gifted and ordinary children. Forty six schoolchildren and forty eight musicians of three age groups (7-10, 11-13 and 14-17 years old) participated in the study. In experimental session, a test sentence was presented to a subject through headphones with two emotional intonations (joy and anger) and without emotional expression. A subject had to recognize the type of emotion. His/her answers were recorded. The analysis of variance revealed age- and gender-related features of emotional recognition: boys musicians led the schoolchildren of the same age by 4-6 years in the development of mechanisms of emotional recognition, whereas girls musicians were 1-3 years ahead. Musical education in girls induced the shift of predominant activities for emotional perception in the left hemisphere; in boys, on the contrary, initial distinct dominance of the left hemisphere was not retained in the process of further education. 相似文献
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