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991.
AIM:To study the effect of hypoxia-inducible factor 1α (HIF-1α) silencing on the proliferation of hepatoma cells under hypoxia. METHODS:Rat hepatoma cell line CBRH-7919 was used in this study. Hypoxia model was established by treating the cells with cobalt chloride (CoCl2). The expression of HIF-1α was silenced by small interfe-rence RNA. Real-time RT-PCR and Western blotting were used to detect the mRNA and/or protein expression of HIF-1α, vascular endothelial growth factor (VEGF), p21 and cyclin D1 in CBRH-7919 cells under hypoxia. The proliferation of CBRH-7919 cells was measured by the technique of 5-bromo-2’-deoxyuridine (BrdU) incorporation. RESULTS:The expression of HIF-1α and VEGF at mRNA and protein levels was significantly increased under hypoxia (P<0.05). Silencing of HIF-1α significantly inhibited the expression of HIF-1α, VEGF and cyclin D1 at mRNA and/or protein levels, while increased the protein expression of p21 (P<0.05). The BrdU-positive cells in HIF-1α siRNA transfection group were significantly less than those in control group. CONCLUSION:HIF-1α silencing significantly inhibits the proliferation of hepatoma cells under hypoxia. 相似文献
992.
《Soil Science and Plant Nutrition》2013,59(4)
(Jpn. J. Soil Sci.Plant Nutr., 77, 273–281, 2006) “Kitanokaori” is a new variety of winter wheat (Triticum aestivum L.) for bread use bred at the National Agricultural Research Center for Hokkaido Region. The grain protein content of wheat for bread use should be higher than 120 g kg?1. Much nitrogen application is necessary to obtain high grain protein content. Therefore, it is necessary to determine the optimum amount of nitrogen to obtain the required protein content and to prevent nitrogen from remaining in the soil. Field experiments were conducted for four years from sowing in 2000 to study the effect of the amount of nitrogen and the time of top-dressing. In the experiment in which sowing was carried out in 2003, nitrogen treatments were 40, 40–60, 40–60–0–60, 40–60–0–60–30, 40–60–0–60–60, 40–60–60–60, 40–60–60–60–30, 40–60–60–60–60, 40–60–30–30, 40–60–30–30–30 and 40–60–30–30–60 (each value showing the amount of applied nitrogen at sowing · re-growing stage · panicle formation stage · flag leaf stage · full heading stage, kg ha?1). The experiments were conducted in Andosol, which has moderate nitrogen fertility, and in Histosol, which is fertile soil. Kitanokaori did not lodge with high-applied nitrogen, and both yield and protein content increased with an increase in applied nitrogen. In a moderate climate, Kitanokaori reached a protein content of 120 g kg?1 when the amount of absorbed nitrogen was about 190 kg ha?1, and the yield was about 7·8 Mg ha?1 at that time. The top-dressing at the panicle formation stage was effective to raise the yield and the top-dressing at the full heading stage was effective to raise the grain protein content. It is recommended that the amount of applied nitrogen should be 160 kg ha?1 until the flag leaf stage, and additional nitrogen should be applied at the full heading stage to obtain a grain protein content of more than 120 g kg?1. Nutritional diagnosis at the full heading stage will be necessary to determine whether more nitrogen is needed to achieve the required protein content. When the amount of total applied nitrogen did not exceed 220 kg ha?1, the amount of absorbed nitrogen was over 90% of applied nitrogen, and there was little inorganic nitrogen in the soil after harvest. Therefore, it was considered that the residue of nitrogen in the soil was small within 220 kg ha?1 of nitrogen application, while favorable growth and high yield were obtained. 相似文献
993.
《Journal of Crop Improvement》2013,27(1-2):227-260
Abstract Pigeonpea (Cajanus cajan [L.] Millsp.), known by several vernacular and trade names such as red gram, tuar, Angola pea, Congo pea, yellow dhal and oil dhal, is one of the major grain legume crops of the tropics and sub-tropics. It is a favorite crop of small holder dryland farmers because it can grow well under subsistence level of agriculture and provides nutritive food, fodder, and fuel wood. It also improves soil by fixing atmospheric nitrogen. India by far is the largest pigeonpea producer where it is consumed as decorticated split peas, popularly called as ‘dhal’ In other countries, its consumption as whole dry seed and green vegetable is popular. Its foliage is used as fodder and milling by-products form an excellent feed for domestic animals. Pigeonpea seeds contain about 20-22% protein and appreciable amounts of essential amino acids and minerals. Dehulling and boiling treatments of seeds get rid of the most antinutritional factors such as tannins and enzyme inhibitors. Seed storage causes considerable losses in the quality of this legume. The seed protein of pigeonpea has been successfully enhanced by breeding from 20-22% to 28-30%. Such lines also agronomically performed well and have acceptable seed size and color. The high-protein lines were found nutritionally superior to the cultivars because they would provide more quantities of utilizable protein and sulfur-containing amino acids. 相似文献
994.
章晓燕 《农业图书情报学刊》2010,22(8):45-48
资源丰富的公共数字图书馆有提高全民素质、促进科技发展和社会进步的重大意义。为了克服资金不足的困难,可以在政府投资主导下,通过大企业资助建设行业技术资源库;和信息技术企业联合共建;和知识产权人合作共建;读者部分付费等多种渠道来进行资源建设。电子资源分布式建设和存储,在国家级平台下形成共享,以取得较好的资源建设效果。 相似文献
995.
[目的]探讨大豆高蛋白组合杂交F4代蛋白质含量与其亲本的相互关系。[方法]2005年以蛋白质含量高(45.00%以上)或产量高的8个大豆品种或品系为亲本,配制6个杂交组合进行杂交,2008年获得杂种F4代相关资料,分析杂种F4代蛋白质含量与亲本的相关关系。[结果]双亲蛋白质含量中值,尤其是母本蛋白质含量对F4代蛋白质含量仍有很大影响,呈正相关;高蛋白组合F4代蛋白质含量分离较大,蛋白质含量降低,低于双亲;F4代蛋白质含量与单株产量呈负相关,与百粒重呈正相关;F4代蛋白质含量与亲本的熟期差异呈负相关,相关性不显著。[结论]若要提高大豆F4代蛋白质含量,应选择蛋白质含量高的材料作为母本;在F4代单株个体的选择上,为保证后代产量应选择大粒型为主。 相似文献
996.
程应红 《农业图书情报学刊》2009,21(4):110-113
基于国外图书馆法的产生和现状。分析了各国图书馆立法的实践,认为现阶段我国图书馆事业立法,应立足于我国国情。当务之急应尽快制定《中华人民共和国图书馆法》作为基本法,然后具体细化。并提出了我国图书馆法应着重解决的几个问题。 相似文献
997.
998.
郝勤 《农业图书情报学刊》2009,21(8):199-201
冲突是组织中常见的一种对抗性的人际互动形式。本文阐述了冲突的分类、影响,并提出冲突管理在图书馆组织中的应用。 相似文献
999.
高校图书馆休闲文化提供模式研究 总被引:3,自引:0,他引:3
马花如 《农业图书情报学刊》2009,21(8):211-212,216
提供休闲文化已经成为高校图书馆新的发展趋势,在分析休闲文化的基础上,提出了高校图书馆提供休闲文化的意义,并提出了休闲文化应包括图书馆建筑物本身、图书馆的空间环境、休闲资源、休闲活动、休闲阅读区等。 相似文献
1000.
数字资源整合核心领域研究进展 总被引:2,自引:0,他引:2
田玉晶 《农业图书情报学刊》2009,21(3):36-39
从发展历程、研究内容、学科特点及国际研究热点问题和国内发展现状等方面对数字资源整合进行了探讨,总结了研究过程中出现的问题,并对未来的研究趋势做了预测。 相似文献