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活性氧在海带抗褐藻酸降解菌感染中的作用 总被引:3,自引:0,他引:3
海带是我国大型经济海藻养殖的主要对象 ,养殖历史长 ,用途广泛。海带人工育苗是发展我国海带养殖事业的一个重要环节。海带病烂 (烂柄病 ) ,尤其在育苗期 ,将造成很大的经济损失。研究指出 ,海带的病烂与褐藻酸降解菌的大量繁殖有关[1- 3 ] 。褐藻酸降解菌是海带藻体上主要附生细菌 ,正常情况下并不引起病烂 ,但若养殖环境恶化 ,如过于密植、损伤、温度过高等 ,使海带的抵抗力下降 ,细菌易于侵入并大量繁殖而导致病害。本文以褐藻酸降解菌为病原细菌 ,研究海带活性氧的产生及其在抵抗褐藻酸降解菌感染过程中所起的作用 ,以期为揭示海带活性… 相似文献
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世界上养殖生产很多贝类,我国有世界上历史最为悠久的贝类养殖产业,可是贝类人工育苗产业化才只有半个世纪的时间,我国在这一科学和生产领域起到了带头和领先的作用。现在需要建设生态环境优美而又科学合理的贝苗工厂,在贝类人工育苗产业化的基础上,进行选种育种和品种培育,促使贝类养殖的科学和生产再有重大的进步和发展。介绍了我国贝类人工育苗产业化的由来,以及贝类人工育苗的发展方向。 相似文献
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海带(Laminaria japonica)和紫菜(Porphyra)均为经济价值较高的海藻。是人们喜爱的美味食品,海带还是提制碘、甘露醇和褐藻胶的主要工业原料。目前我国已经实现了海带和紫菜的全人工养殖。海带产量居世界首位,产品不仅满足了我国人民生活的需求,还远销世界五大洲。我国先后建成了世界上最大的褐藻胶提制工业和第二大紫菜生产工业,在世界上产生了举世瞩目的影响。究其原因,这是与对海带和紫菜的基础理论研究同养殖生产紧密结合分不开的。其中特别是和深入研究海带、紫菜的生活史及其各阶段的生活条件密切相关。下面分别谈谈海带和紫菜的生活史及其与人工养殖的关系。 相似文献
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海水经济贝类在海水养殖中占有重要的地位,开展贝类育种、育苗对提高重要经济贝类的产量和质量意义重大。多倍体育种作为贝类育种的方法之一,研究者希望通过这种方法,诱导出个体大、生长快、肉质好的三倍体贝类,以提高群体生长速度,改善经济性状,增强养殖生物的抗逆性。对多倍体贝类的亲贝培育、育种原理、诱导方法、检测技术,以及生物学性状作了综述,最后探讨了多倍体研究中存在的主要问题。 相似文献
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高产高碘海带新品种的培育 总被引:6,自引:0,他引:6
《遗传学报》1976,(3)
海带是我国人民长期以来习惯食用的副食品。解放后,我国海带养殖事业迅速发展,从北到南广泛开展人工养殖,特别是在无产阶级文化大革命的推动下,海带养殖面积成倍扩大。这就要求培育不同性状的新品种来适应不同的环境条件,以提高单位面积产量。同时,由于利用海带作为原料的藻胶工业的发展,需要大量回收副产品,包括碘,积极开展综合利用,从而提出了培育高碘海带新品种的迫切要求,以解决工业的需要。 相似文献
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马海飞 《中国生物工程杂志》1994,14(2):28-30
鳗鲡(Anguillajaponica)人工育苗技术研究进展马海飞(中国科学院发育生物学研究所,北京100080)一、鳗鲡人工育苗技术研究的意义鳗鲡养殖是我国及周边国家和地区水产动物养殖业的一项重要内容,也是我国水产养殖的主要创汇项目之一。我国周边地区和国家鳗鲡养殖中使用的鳗鲡苗主要产自我国,全部为天然苗。鳗鲡的产卵场在我国沿海附近。每年春季鳗苗进入我国河口水域。由于自然资源自身的产量有限,加上工业污染造成资源破坏,现 在天然苗的捕获量已经越来越不能满足日趋增长的市场需求,因此人工繁殖鳗苗技术的研究和开发已迫在眉睫。 相似文献
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Although the importance of the endosperm as a food store inmany angiosperm seeds is well known, its significance duringearly embryogenesis has been neglected. In many interspecifichybrids, and in some other situations, embryos do not developfully and abort. It has often been stated that this is causedby the endosperm failing to conduct sufficient nutrients tothe embryo, but seldom has it been suggested that the endospermactively controls most of the early stages of morphogenesisof the embryo. Information gleaned from a broad survey of theliterature, combined with additional evidence presented here,obtained fromSolanum incanumand interspecific hybrids, indicatethat the endosperm is dynamic and very active in regulatingearly embryo development. This requires highly integrated geneticcontrol of rapidly changing metabolism in the endosperm. Ininterspecific hybrids, lack of coordination may cause unbalancedproduction of growth regulating substances by the endospermand hence abortion of the embryo, or even unregulated productionof nucleases and proteases resulting firstly in autolysis ofthe endosperm and then digestion of the embryo. The endospermmay thus serve to detect inappropriate hybridization of speciesor ploidy levels and so prevent waste of resources by producingseeds that would result in sterile hybrids or unthrifty subsequentgenerations. This discriminatory function of the endosperm hasdiminished during evolution and domestication of the crop plantSolanummelongenaL.Copyright 1998 Annals of Botany Company Solanum, embryo morphogenesis, endosperm, hybrid, seed development. 相似文献
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Höpfl G Ogunshola O Gassmann M 《American journal of physiology. Regulatory, integrative and comparative physiology》2004,286(4):R608-R623
For most organisms oxygen is essential fo life. When oxygen levels drop below those required to maintain the minimum physiological oxygen requirement of an organism or tissue it is termed hypoxia. To counter act possible deleterious effects of such a state, an immediate molecular response is initiated causing adaptation responses aimed at cell survival. This response is mediated by the hypoxia-inducible factor-1 (HIF-1), which is a heterodimer consisting of an alpha- and a beta-subunit. HIF-1 alpha protein is stabilized under hypoxic conditions and therefore confers selectivity to this response. Hypoxia is characteristic of tumors, mainly because of impaired blood supply resulting from abnormal growth. Over the past few years enormous progress has been made in the attempt to understand how the activation of the physiological response to hypoxia influences neoplastic growth. In this review some aspects of HIF-1 pathway activation in tumors and the consequences for pathophysiology and treatment of neoplasia are discussed. 相似文献
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Michele Rivkin-Flsh 《Medical anthropology quarterly》2000,14(1):119-120
Pragmatic Women and Body Politics. Margaret Lock and Patricia A. Kaufert. eds. Cambridge, UK: Cambridge University Press, 1998. xii +364 pp.
Maternities and Modernities: Colonial and Postcolonial Experiences in Asia and the Pacific. Kalpana Ram and Margaret Jolly. eds. Cambridge, UK: Cambridge University Press, 1998. xiv. 305 pp. 相似文献
Maternities and Modernities: Colonial and Postcolonial Experiences in Asia and the Pacific. Kalpana Ram and Margaret Jolly. eds. Cambridge, UK: Cambridge University Press, 1998. xiv. 305 pp. 相似文献
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环腺苷酸应答元件结合蛋白与学习记忆 总被引:2,自引:0,他引:2
环腺苷酸(cAMP)应答元件结合蛋白(cAMP response element binding protein,CREB)是一种核转录因子,可与cAMP反应元件结合,调节基因转录,具有调节精子生成,昼夜节律,学习记忆等功能.近年来关于其在学习记忆中的作用成为医学研究热点.CREB是神经元内多条信息传递途径的汇聚点,参与长时记忆形成和突触可塑性.长时记忆(long-term memory)形成需依赖CREB介导的基因转录,干扰或抑制CREB活性可破坏长时记忆.长时程增强(long-term potentiation,LTP)是研究学习记忆的理想模型,在LTP诱导和维持过程中均可观察到CREB活性持续升高.但增龄过程中,海马CREB活性下降,影响学习记忆功能,与许多神经退行性疾病发生有关. 相似文献
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Studies of human constitution and mental features are traditionally among the main concepts of anthropological research. In
this research, we attempted to discover connections between morphological and constitutional features and self-esteem in children
and adolescents. Such a connection was discovered in some studied age groups. The obtained results could serve as a basis
for further studies in this field. 相似文献