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引起生物转基因沉默的因素、作用和对策 被引量:1
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作者 魏决 《四川食品与发酵》 2002年第2期13-16,共4页
基因沉默是生物体基因表达调控的一种重要的机制,它具有重要生物学功能,转基因沉默是导致外源基因不能在生物体中正常表大的主要原因,并已成为转基因植物商品化生产的严重阻碍。本文就基因沉默的机制作了简要综述,并对基因沉默在生物生... 基因沉默是生物体基因表达调控的一种重要的机制,它具有重要生物学功能,转基因沉默是导致外源基因不能在生物体中正常表大的主要原因,并已成为转基因植物商品化生产的严重阻碍。本文就基因沉默的机制作了简要综述,并对基因沉默在生物生长发育中的作用及如何消除植物中外源因沉默,促使其高效表达的策略进行了初步的探讨。 展开更多
关键词 基因沉默 转基因 基因表达 生物生长发育
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锌的生物学效应 被引量:2
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作者 李慎涛 吴文甲 《黑龙江畜牧兽医》 CAS 北大核心 1989年第6期35-36,共2页
锌是人和动物所必需的微量元素之一。自1869年Raulin发现锌与生物生长发育有关以来,锌在生物学和医学的很多领域又获得突破性的进展。其生物学效应和药理作用也日益受到人们的重视。现根据近期的大量文献,将其生物学效应综述如下:
关键词 药理作用 动物实验 生物生长发育 氧自由基 免疫功能 细胞分化 脂质过氧化反应 机体细胞免疫 脾脏重量 缺锌
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浅谈生物课外活动在农村学校的开展 被引量:1
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作者 廖慧萍 《广西师范大学学报(自然科学版)》 CAS 2000年第S3期179-180,共2页
关键词 生物课外活动 农村学校 课外活动小组 组织形式 课堂教学 农业生产 理论联系实际 个人活动 创造性 生物生长发育
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Wnt/β-catenin信号通路在慢性肾炎中的作用及研究进展 被引量:5
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作者 冒慧敏 杨丽平 +1 位作者 占永立 李平 《中国中西医结合肾病杂志》 2014年第11期1033-1034,共2页
Wnt/β-catenin信号通路是生物进化过程中极为保守的通路。其功能涵盖了生物生长发育、疾病、死亡、细胞形态与功能的分化、内环境稳态的维持等。在肾脏方面,Wnt/β-catenin通路亦逐渐成为学者关注的焦点之一。目前研究表明,该通路在肾... Wnt/β-catenin信号通路是生物进化过程中极为保守的通路。其功能涵盖了生物生长发育、疾病、死亡、细胞形态与功能的分化、内环境稳态的维持等。在肾脏方面,Wnt/β-catenin通路亦逐渐成为学者关注的焦点之一。目前研究表明,该通路在肾脏肿瘤的发生和发展[1]、急性肾小管损伤时肾小管的再生与修复[2]以及多囊肾的发病机制[3]中起关键作用。 展开更多
关键词 CATENIN 慢性肾炎 Wnt 信号通路 肾脏肿瘤 急性肾小管损伤 系膜细胞 细胞外基质 阿霉素肾病 生物生长发育
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生命进化的分子冗余特征 被引量:1
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作者 李跃强 盛承发 《科学中国人》 1996年第7期38-41,共4页
随着现代科学技术的迅速发展,人们对涉及人类自身的最基本问题,如生命的本质是什么越来越关注。计算机科学家声称通过指令可使计算机复制自身,而美国化学家Rebek在试管中创造出一种酰胺分子,该分子以一种类似DNA复制的方式拷贝。那么,... 随着现代科学技术的迅速发展,人们对涉及人类自身的最基本问题,如生命的本质是什么越来越关注。计算机科学家声称通过指令可使计算机复制自身,而美国化学家Rebek在试管中创造出一种酰胺分子,该分子以一种类似DNA复制的方式拷贝。那么,计算机和有机小分子是否就成了生命呢?严格说来它们还不是生命。生命除了有自我复制的能力外,还应该具有每代增加变异并向前进化的能力;也就是说生命体可以通过产生变异为生命进化提供动力,从而使生命体沿着由简单到复杂、由低级向高级的路线向前发展,最终不断适应新的外界环境条件,达到生命体的不断完善。 展开更多
关键词 生长冗余 生物大分子进化 生命进化 生命体 生物体内 生物生长发育 可调节性 生物进化 多拷贝 组蛋白
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地球静电研究与21世纪
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作者 徐好民 《太原师范学院学报(社会科学版)》 1999年第4期2-3,共2页
关键词 21世纪 静电 地球科学 道法自然 地震预报 生物生长发育 气象灾害 能源问题 卫星云图 人类持续发展
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论农业工业化
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作者 许经勇 《福建论坛(经济社会版)》 1987年第6期22-25,2,共5页
在农业生产的物质技术基础依然十分薄弱的情况下,农业生产持续增长的途径何在?农业工业化是社会生产发展的必然趋势,那么它会完全消除农业部门与工业部门的差别吗?在农业诸部门农业工业化的不同发展程度受制于哪些因素?这些问題迫切需... 在农业生产的物质技术基础依然十分薄弱的情况下,农业生产持续增长的途径何在?农业工业化是社会生产发展的必然趋势,那么它会完全消除农业部门与工业部门的差别吗?在农业诸部门农业工业化的不同发展程度受制于哪些因素?这些问題迫切需要从理论上加以解决。本期发表许经勇同志的《论农业工业化》一文,对此做了深入的探讨,文章论证充分,希望能启发您的思路。 展开更多
关键词 农业工业化 农业部门 农业生产 物质技术基础 工业部门 许经勇 持续增长 生产条件 社会生产发展 生物生长发育
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中国农业的演变及其历史作用
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作者 叶依广 《古今农业》 1990年第2期90-93,共4页
中国是世界上农业历史最悠久的国家之一,有近万年的历史。在古代,我国农业一直是以精耕细作闻名于世的。一、中国农业的起源与发展我国农业的发展,大体上经历了如下三个阶段。(一)原始农业在原始社会的早期,我们的祖先就开始了渔猎和采... 中国是世界上农业历史最悠久的国家之一,有近万年的历史。在古代,我国农业一直是以精耕细作闻名于世的。一、中国农业的起源与发展我国农业的发展,大体上经历了如下三个阶段。(一)原始农业在原始社会的早期,我们的祖先就开始了渔猎和采集活动,借以维持共生存。后来,由于人类的不断繁衍,单纯依靠大自然的有限恩赐已经不能满足人们生活的最低要求。 展开更多
关键词 农业现代化 采集活动 农业资源 当代农业 出口商品 资金积累 农村产业结构 农副产品加工 生物生长发育 农牧结合
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物候、天时和渔业资源的保护利用
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作者 高梁 《古今农业》 2001年第4期46-49,共4页
人类远在旧石器时代就已经从事渔猎活动。通过长期的实践,早就认识到许多生物的活动是与环境条件特别是与气候条件的变化紧密相关的。生物的活动,随着气候的周期变化,也呈现周期变动的现象。如鱼类的定期洄游,就是最明显的例子。这种生... 人类远在旧石器时代就已经从事渔猎活动。通过长期的实践,早就认识到许多生物的活动是与环境条件特别是与气候条件的变化紧密相关的。生物的活动,随着气候的周期变化,也呈现周期变动的现象。如鱼类的定期洄游,就是最明显的例子。这种生物对应“天时”(气候、季节)变动而出现的变动现象,称之为物候。古代,人们最初对农时的认识和掌握来自物候。因为人们最容易感觉和直接观察到的是某些动物的出现和消失, 展开更多
关键词 渔业资源 鲥鱼 鄱阳湖 生物生长发育 保护利用 《吕氏春秋·十二纪》 先秦时期 海洋渔业 周期变化 周期变动
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Effect of Microbial Inoculum Fertilizer on the Growth and Yield of Super Hybrid Rice 被引量:1
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作者 郭夏宇 艾治勇 《Agricultural Science & Technology》 CAS 2015年第11期2396-2398,共3页
The research designed four application quantities of 0, 2 250, 4 500 and 6 750 g/hm2 based on Liangyou No. 959 to explore the effects of microbial inocu- lure fertilizer on growth and yield of super hybrid rice. The r... The research designed four application quantities of 0, 2 250, 4 500 and 6 750 g/hm2 based on Liangyou No. 959 to explore the effects of microbial inocu- lure fertilizer on growth and yield of super hybrid rice. The results indicate that the treatment with traditional fertilizers and 4 500 g/hm2 HYT microbial inoculum fertilizer performed the best, where average number of tiller was 2.4 more than that of the control; the number of effective ear was 11.05% higher; yield increased by 10.3%. These have demonstrated that microbial inoculum fertilizer is of great value in pro- motion on super hybrid rice production. 展开更多
关键词 Microbial inoculum fertilizer Super hybrid rice Growth and development Yieid
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农业联产承包责任制的发展前景浅议
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作者 张复成 《理论探索》 1984年第10期10-19,共10页
现在,农业联产承包责任制已经受到绝大多数人的翘指称颂。就连许多怀疑、反对过它的人,也被它的巨大功绩折服了。然而,对于它的发展前景,却并不是人人都很明了的。我认为,联产承包责任制对我国农业发展和农村建设的影响将是极其广泛和... 现在,农业联产承包责任制已经受到绝大多数人的翘指称颂。就连许多怀疑、反对过它的人,也被它的巨大功绩折服了。然而,对于它的发展前景,却并不是人人都很明了的。我认为,联产承包责任制对我国农业发展和农村建设的影响将是极其广泛和深远的, 展开更多
关键词 农业现代化 发展前景 农村建设 家庭经营 农村工业 经营规模 农工商一体化 小流域治理 生物生长发育 专业化生产
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农业现代化与农民教育
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作者 周定滨 《西华师范大学学报(哲学社会科学版)》 1992年第5期127-129,共3页
一、农业现代化是实现社会主义现代化的重要组成部分。党的十三届八中全会明确提出:“没有农业现代化,就不可能有整个国民经济的现代化。”党和国家制定的十年规划和八五计划,都把大力加强和发展农业作为重点并当作首要任务。十三届八... 一、农业现代化是实现社会主义现代化的重要组成部分。党的十三届八中全会明确提出:“没有农业现代化,就不可能有整个国民经济的现代化。”党和国家制定的十年规划和八五计划,都把大力加强和发展农业作为重点并当作首要任务。十三届八中全会专门作了“关于进一步加强农业和农村工作的决定”。 展开更多
关键词 农业现代化 农村工作 农民教育 农业建设 农业生产 工农业产品 人口计算 物质技术基础 无机农业 生物生长发育
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人类世界面临的五大威胁
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作者 警言 《教育学报》 1995年第7期39-39,共1页
人类世界面临的五大威胁警言核战争、人口增长、贫穷、能源的滥用和有毒废物对环境的污染是当前人类世界面临的五大威胁。1.核战争。一旦发生了核战争,立即就会有数百万人死亡,而长期的核战争影响则更为严重。地球表面供生物生长发... 人类世界面临的五大威胁警言核战争、人口增长、贫穷、能源的滥用和有毒废物对环境的污染是当前人类世界面临的五大威胁。1.核战争。一旦发生了核战争,立即就会有数百万人死亡,而长期的核战争影响则更为严重。地球表面供生物生长发育的那层薄薄的生物圈,将受到严重的... 展开更多
关键词 人类世界 有毒化学品 人口增长 有毒废物 有毒化学废物 电力变压器 多氯联苯污染 遗传变异 生物生长发育 环境影响
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Effect of Fertilization in Organic Nursery for Later Growth and Fruiting of Apple Trees in the Orchard 被引量:1
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作者 Zygmunt Stanislw Grzyb Wojciech Piotrowski Lidia Sas Paszt 《Journal of Life Sciences》 2015年第4期159-165,共7页
There is a deficiency of nurseries in the world producing fruit trees using the organic material management. However, such material has been produced since 2009 at the Research Institute of Horticulture in Skierniewic... There is a deficiency of nurseries in the world producing fruit trees using the organic material management. However, such material has been produced since 2009 at the Research Institute of Horticulture in Skierniewice. To stimulate plant growth, various biopreparations were applied in an organic nursery. Apple trees ('Topaz'/M26) obtained from the organic nursery were used to establish an orchard in 2011. One of the combinations in the orchard consisted of trees produced in a conventional nursery. Trees whose maidens had not been fertilized at all in the organic nursery served as the control. The study was conducted for four years (2011-2014). The least vigorously growing trees were the control trees and those that had been treated in the nursery with the preparation Tytanit, and the most vigorously--those that had been treated there with manure and the biopreparations Micosat, Humus Active + Aktywit PM, and BF Quality and BF Amin. Trees whose maidens had been produced by the conventional method did not differ, in terms of growth vigour, from those treated with the biopreparations Humus UP or Vinassa. The highest cumulative fruit yields from the four-year-old trees were obtained in the combinations where the maidens had been treated in the nursery with the biopreparations BF Amin and BF Quality. The type of fertilization applied to maiden trees in the nursery had no significant effect on mean fruit weight, but it influenced the distribution of fruit in size classes. 展开更多
关键词 'Topaz'/M26 BIOPRODUCTS ROOTSTOCK yield fruit size and weight.
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Nitrogen/Ammonium Concentration Response of Vegetable and Flower Crops
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作者 Armando Hemandez-Perez Oscar Gabriel Villegas-Torres +5 位作者 Martha Lilia Dominguez-Patifio Martha Lilia Dominguez-Patino Hector Sotelo-Nava Antonio Rodriguez-Martinez Luis Alonso Valdez-Aguilar Iria Alia-Tejacal 《Journal of Agricultural Science and Technology(B)》 2014年第4期261-266,共6页
Nitrogen (N) is the element with the greatest influence on the growth of vegetables and ornamentals, however, form of delivery, either as nitrate (NO3) or ammonium (NH4+) has different effects on plant developm... Nitrogen (N) is the element with the greatest influence on the growth of vegetables and ornamentals, however, form of delivery, either as nitrate (NO3) or ammonium (NH4+) has different effects on plant development. The NO3 is the main form of N that plants absorb, but when it is the only source of N that has slight effects on root growth, no effects over enzymatic activities, and stimulates the absorption and translocation of cations within the plant. The NH4+ is the easiest way of assimilation but is highly toxic when the only source or with respect to the concentration of NO3 is too high. To avoid toxicity, the NH4+ must not exceed 20% of the total N amount in the formulation, however, it is important to consider the species, variety and environmental conditions. The N as supplied also affects the resistance or susceptibility of plants to diseases, but depends on the species and the type of pathogen. 展开更多
关键词 Nitrate AMMONIUM VEGETABLES ORNAMENTAL toxicity nutrition.
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Modeling of Organ Morphology and Biomass Dynamics in Rice
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作者 D. Yan L. T. Wilson +5 位作者 Y. Yang J. Lv J. C. Medley L. Zhu Y. Guo S. O. P. B. Samonte 《Journal of Agricultural Science and Technology(B)》 2011年第7期1013-1024,共12页
Physiological processes governing rice plant light capture and subsequent crop growth and development are intimately tied to canopy architecture. Conversely, the production and spatial orientation of organs are depend... Physiological processes governing rice plant light capture and subsequent crop growth and development are intimately tied to canopy architecture. Conversely, the production and spatial orientation of organs are dependent on the underlying physiological processes. An integrated functional-architectural modeling system would allow greater refinement of intra- and inter-plant interactions, facilitate the incorporation of additional mechanistic processes, allow greater integration of processes across multiple structural scales, and improve the accuracy of predictions. The objective of this study is to quantify the physiological bases for organ morphological development of 3 rice cultivars (Banks, IR68886B, and their hybrid Banks × IR68886A). Detailed organ morphological data were obtained through repeated field observations and destructive samplings over the growing season, including leaf length, width, area, mass, and leaf phyllochron; sheath length, diameter and mass; internode length, diameter and mass; panicle length; stem and tiller number. The result showed that the plant age (GDD, 〉 10 ℃ d) at the first full leaf initiation (node = 2) was 147.92, 154.35, 166.23 for Banks, IR68886B, and Banks × IR68886A respectively. Banks × IR68886A produced 18 nodes, while IR68886B produced 17 nodes, and Banks 16 nodes. The Specific Leaf Weight (SLW, mg cm2) was fairly constant (about 6 mg cm2) during the growing season for the 3 cultivars, and appears to slowly increase for the latter nodes. The leaf length and SLW of Banks × IR68886A was more than Banks and IR68886B. Specific internodes weight of Banks x IR68886A was higher than IR68886B ×and Banks. Growing duration for Banks × IR68886A is longer than Banks and IR68886B. Banks × IR68886A shows positive heterosis,, and the mid-parent heterosis (MPH) for panicle length was 26.74% and that for stem and tiller number was 135.00%. Results from the experiments were used to parameterize a rice functional-architectural model that simulates organ dynamics and renders organ growth in a 3-dimensional space over the rice growing season. 展开更多
关键词 RICE leaf SHEATH INTERNODE PANICLE MORPHOLOGY development.
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Effect of Integrated Nutrient Management on Growth and Productivity of Hybrid Rice
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作者 Spurti Mondal Malavathu Mallikarjun +2 位作者 Mainak Ghosh Dulal Chandra Ghosh Jagadish Timsina 《Journal of Agricultural Science and Technology(B)》 2015年第5期297-308,共12页
Sustaining rice (Oryza sativa L.) productivity at high level is a great challenge, particularly in areas where rice productivity declines in spite of following recommended nutrient management practices. Nutrient man... Sustaining rice (Oryza sativa L.) productivity at high level is a great challenge, particularly in areas where rice productivity declines in spite of following recommended nutrient management practices. Nutrient management by integrating organic manures, inorganic fertilizers and biofertilizers may play an important role in improving and sustaining rice productivity. In this study, the authors tried to evaluate the suitable proportion of organic manures and inorganic fertilizers along with biofertilizer to maximize growth and productivity of hybrid rice on sandy-loam lateritic soils of West Bengal, India. The crop having 50% recommended dose of fertilizer (RDF) + 50% recommended dose of nitrogen (RDN) through mustard oil cake (MOC) and 75% RDF + 25% RDN through MOC + biofertilizer significantly increased plant height, number of tillers/m2, leaf area index (LAI), dry matter accumulation (DMA) and crop growth rate (CGR) at initial and vital period of grain growth over those of 25% RDF + 75% RDN through MOC and 100% RDN through MOC. The former two treatments also increased number of panicles/m2 and number of grains/panicle over those of only organic manuring (100% RDN) or only chemical fertilization (100% RDF) or 25% RDF + 75% RDN through MOC. Crop with 75% RDF + 25% RDN through MOC + biofertilizer or 50% RDF + 50% RDN through MOC produced 20.2%-33.8% higher grain yield and 11.0%-33.3% greater straw yield, and paid higher gross and net returns over other treatments. This study suggests growing hybrid rice with 75% RDF + 25% RDN through MOC + biofertilizer or 50% RDF + 50% RDN through MOC for better growth, higher productivity and greater profit. 展开更多
关键词 Hybrid rice BIOFERTILIZER imegrated nutrient management.
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Chlorocholine Chloride Induces Cacao Reproductive Development Leading to Improved Fruitlets Productivity of Cacao Trees in the Field
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作者 Djoko Santoso Samanhudi Roedy Purwanto 《Journal of Agricultural Science and Technology(B)》 2013年第7期517-524,共8页
Fruitlet abscission (cherelle wilt) is a major factor contributing to lower productivity of cacao plantation in Indonesia. An attempt was made to reduce such cherelle wilt by spraying plant growth retardants (PGRs... Fruitlet abscission (cherelle wilt) is a major factor contributing to lower productivity of cacao plantation in Indonesia. An attempt was made to reduce such cherelle wilt by spraying plant growth retardants (PGRs) on cacao trees at about 10 weeks before flowering session. The treatment was repeated every three weeks. Both the flowering initiation time and the number of flowers on the treated trees were improved significantly. With the most effective composition, flowers were initiated at 24 days after spraying (DAS), where as the flowering initiation was 11-day later in the controls. At the 35 DAS, the chlorocholine chloride (CCC) 2,000 treatment induced about 20-80 folds more flowers than the controls. Extended observation was made to assess the treatment effect on the fruiting capacity. The treatments were found to improve fruiting ability by increasing the number of fruits set on the trees and shortening the time for fruit setting. At 20 weeks after the first spraying (WAS) there were on average 12.57 fruits per CCC 2,000-treated tree, as opposed to only 4.14 fruits per untreated tree. Analyses of the metabolites content in the flower cushions of the trees indicated that the reproductive growth is significantly correlated with the increased metabolites particularly the reduced sugar. Exogenous addition of sucrose to the PGR treatment gave greater improvement mainly in the fruiting. In conclusion, foliar spray of CCC induces flowering of cacao tress in the field that leads to improve the fruitlets productivity. 展开更多
关键词 Plant growth retardant induced flowering Theobroma cacao L
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生物教学中学生观察能力的培养
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作者 钱兴华 《无锡教育学院学报》 1999年第2期93-94,共2页
关键词 生物教学 学生观察能力 生物现象 演示实验 观察方法 观察法 亚显微结构 比较观察 课堂小实验 生物生长发育
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COMPARATIVE BIOLOGY OF TWO GEOGRAPHICAL POPULATIONS OF THE SOUTHERN COWPEA WEEVIL, CALLOSOBRUCHUS CHINENSIS (L.) (COLEOPTERA: BRUCHIDAE) IN SOUTHWEST CHINA 被引量:2
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作者 邓永学 王进军 +1 位作者 赵志模 刘怀 《Entomologia Sinica》 CSCD 2003年第4期257-264,共8页
The differences of bionomics and ecologics of the two populations of Callosobruchus chinensis on mung bean (Vigna radiatus) at six constant temperatures ( 20, 25, 28, 30, 32, 35℃) and 75% r. h. were researched. ANOV... The differences of bionomics and ecologics of the two populations of Callosobruchus chinensis on mung bean (Vigna radiatus) at six constant temperatures ( 20, 25, 28, 30, 32, 35℃) and 75% r. h. were researched. ANOVA showed that temperature affected the developmental period and fertility significantly (P<0.05). T-test indicated there was significant difference of the combined immature stages between the two geographical populations at 25 and 32℃ (P<0.05). The average oviposition between the two geographical populations differed significantly at the same temperature (P<0.05). At 30℃ and 75% r. h., effects of 5 commercially grown legume seeds on development and reproduction of the two geographical populations of Callosobruchus chinensis (L.) were researched. The results showed that broad bean and soybean were more suitable for increase for Xichang population in terms of r m values. The adult weight and diameter of emergency hole of the two populations were also compared. According to the differences in the characteristics of development, reproduction, and damage to host seeds between the two geographical populations, conclusion can be drawn that both are different geographical populations. 展开更多
关键词 Callosobruchus chinensis geographical population BIOLOGY
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