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植物种质的玻璃化超低温保存 总被引:19,自引:0,他引:19
植物种质的玻璃化超低温保存技术已受到广泛重视。玻璃化法主要由装载、玻璃化保护液脱水、降温、复温、洗涤这5个环节构成。目前已对百余种植物进行过玻璃化冻存研究,但主要应用于高等植物,而用该法保存藻类获得成功的报道很少。将玻璃化法用于某些藻类种质的冻存将会有广阔的应用前景。 相似文献
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2-细胞期胚胎经激光显微照射(功率为90毫瓦)其中一个卵裂球时能产生明显的损伤光斑,受照射的卵裂球立即停止发育。另一未受照射的卵裂球仍能正常卵裂直至孵化幼鱼,所获得的幼鱼在形态上与正常幼鱼相同。8-细胞或囊胚期胚胎经激光显微照射(功率为372毫瓦)时,则可在受照射的卵裂球上产生明显伤斑,并在照射部位溢出部分细胞内含物,绝大部分胚胎发育成不正常的胚体和各种畸形幼鱼。 相似文献
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美国休斯敦得克萨斯健康中心大学人口统计和群体遗传中心人类遗传学教授威廉·丁·舒尔于1979年2月访华期间在中国科学院遗传研究所作了有关美国遗传学教学情况的介绍,现简介如下: 相似文献
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The Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), has become a worldwide cereal pest with its dispersion to over 30 countries in this century. According to the natural history of its occurrence around the world, it is postulated RWA originated from western or central Asia. The aphid dispersed gradually to Europe and northern Africa, but its big jump across the ocean to North America is still a mystery. There are two overwintering strategies in RWA. The anholocyclic biotype, often reproducing earlier and more offsprings than the holocyclic one, has greater impact on crops in South Africa and United States. According to the experiments on its thermal response, RWA could withstand temperatures below -20℃, while temperatures above 30℃ would be harmful to its survival. The preference to colder condition may determine its distribution on the world. RWA has made great damages to cereal crops worldwide. It caused loss in crop yield by directly feeding on plant nutrition and disturbing the plant metabolism. But its status as plant virus transporter is open to question. By now, the aphid is still a serious pest in many countries and its invasion to more countries and areas maybe continues. Therefore, the research on its biological characteristics as well as its dispersion apparently needs to be enhanced in the future. 相似文献
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螺旋藻中药用成分的综合开发与应用 总被引:5,自引:0,他引:5
综述了螺旋藻中藻蓝蛋白、γ-亚麻酸、螺旋藻多糖、色素等综合开发与应用. 相似文献
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