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排序方式: 共有495条查询结果,搜索用时 31 毫秒
1.
山茱萸具有降血糖、抗氧化、抗肿瘤、抗菌等功能作用,开发山茱萸资源具有重要意义,其研究受到广大科技工作者的关注。为了解近10年来山茱萸的研究现状,本文采用文献计量学方法,以中国学术期刊网络出版总库(CNKI)2009—2018年的数据为检索对象,从年度分布、研究机构、学科分类、期刊来源等方面分析山茱萸研究文献,以期为研究者提供参考。 相似文献
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从药用植物巴戟天根部组织中克隆了3个1–脱氧–D–木酮糖5–磷酸合成酶基因MoDXS1、MoDXS2-1和MoDXS2-2,其全长cDNA分别为2676、2667和2610 bp,编码区序列长度为2154、2121和2190 bp,编码717、706和729个氨基酸。BlastP序列比对分析表明MoDXS蛋白与其他植物的DXS蛋白高度同源;系统进化发育树分析显示,MoDXS蛋白与中粒咖啡和小粒咖啡DXS蛋白亲缘关系最近。MoDXS1、MoDXS2-1和MoDXS2-2蛋白被分别归为clade 1、clade 3和clade 2。MoDXS1在巴戟天根中表达量最高;MoDXS2-1在巴戟天根、茎、叶中的相对表达量差异显著,叶中最高;MoDXS2-2在根中表达量最高,而在茎和叶中最低。MoDXS1、MoDXS2-1和MoDXS2-2基因的5′端上游启动子序列长度分别为2538、732和1744 bp。亚细胞定位预测3个MoDXS均在叶绿体上。 相似文献
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为了查明生物活性成分在黄花草木樨根、茎、叶、子中的含量与分布特征,本研究重点开展了黄花草木樨活性成分的检测及田间开发试验。分别采用凯式定氮法和高效气相色谱法测蛋白质;氨基酸自动分析仪法测氨基酸;气相色谱-质谱、分子蒸馏仪检测脂肪酸;重量法检测皂苷与生物碱;高效液相色谱仪检测香豆素;福林试剂比色法检测多酚;蒽铜-硫酸比色法检测多糖;亚硝酸钠-硝酸铝-氢氧化钠比色法检测黄酮。按产量测算后,得出每公顷牧草生物活性成分的总产量为3016.3 kg/hm2。其中粗蛋白质、氨基酸和粗脂肪酸原料的产量分别为1400.6 kg/hm2,112.2 kg/hm2,1246.8 kg/hm2。有效成分皂苷、生物碱、多酚、香豆素的产量分别为97.0 kg/hm2、77.9 kg/hm2、41.7 kg/hm2、40.1 kg/hm2。上述成分经分离提取纯化后,可作为开发医药、食物、化工等生物技术产品的天然原料。本文为开发利用植物自然资源提供了新的途径。 相似文献
5.
Atsuko Uragami Atsushi Yamasaki Kentaro Matsuo Takayuki Yamaguchi Hideo Tokiwa Tamio Takizawa 《The Journal of Horticultural Science and Biotechnology》2017,92(5):530-538
Rootstock-planting forcing culture was developed in asparagus to harvest spears even during the seasons when the plants become dormant, but the demand for them high. In this study, cumulative hours during which the air temperature remained lower than 5°C, i.e. chilling hours (CHs), were calculated to determine dormancy breakage for asparagus cultures. We also measured CIELab colour values for cut stems immediately before rootstock digging, and determined whether they could be substituted and/or compensated for CHs while evaluating asparagus plant productivity in different low-temperature backgrounds, and obtained regression equations for yield estimation. Asparagus seedlings were cultivated in seven different regions across Japan and brought to the study site for harvesting. Our regression equation based on CHs and rootstock weight for yield estimation had relatively high fitness (adjusted R2 = 0.5795). The colour values of cut stalks at rootstock digging can also be used to evaluate their productivity. These values can be useful in regions where CHs cannot be determined, although their effectiveness was slightly lower than that of CHs of areas adjacent to the study sites. 相似文献
6.
川牛膝是我国重要大宗药材,但近年来品质退化严重,品种真伪混杂。为深入研究川牛膝有效成分积累的分子基础,采用第二代测序技术利用Illumina Hi-seq 2000测序平台对川牛膝进行全基因组测序,使用AByss进行初步组装,得到一个包含大量基因组序列信息的数据集,并对其进行重复序列及编码序列注释。在该测序结果基础上,初步预测得到川牛膝体内甾体合成途径,并对鉴定川牛膝真伪的SCAR分子标记进行了初步定位,为研究川牛膝主要有效成分杯苋甾酮的合成途径,改良川牛膝品质提供了基础。 相似文献
7.
António V Sykes Pedro M Domingues Lorenzo Márquez José P Andrade 《Aquaculture Research》2011,42(3):441-449
The effects of different tank colours (white, yellow sandy and black) on the growth, mortality and biomass production were studied for hatchling and early juvenile cuttlefish. For hatchlings, the use of different colour tanks did not promote differences in growth due to the higher variability (standard deviation) found in the white‐ and sand‐coloured tanks. Black tanks promoted the lowest and highest values for total mortality and biomass respectively. For juveniles, the use of different tank colours promoted different growth (P<0.05), but not mortality. Black tanks promoted the best results in terms of growth and biomass. The results obtained in the present study advise the use of black (or dark colour) tanks in the hatchling and early juvenile stages to reduce the standard deviations associated with growth, mortality and biomass production. This will contribute to minimize problems associated with slow and fast growers and competition. 相似文献
8.
Asparagus is especially suitable for polyploidy breeding. The aim is to develop clone-based hybrid varieties, in particular male 4 × varieties. For this purpose, genetically divergent diploid idiotypes * * Idiotye (according to Reiger et al. 1976) is the sum of total hereditary determinants of an organism, consisting of its genotype (all determinants localized in the chromosomes) and its plasmotype (all determinants localized extra-chromosomally).
) are subjected to mitotic or meiotic polyploidization. In developing hybrid partners, special attention is paid to resistance in addition to yield and quality characters. Early diagnoses are applied in selection so as to shorten breeding times. Somaclonal variations may occur relatively often on in vitro propagation; these need to be eliminated. Triplex and quadruplex type males are suitable for paternal hybrid partners. Strong inbreeding depressions need to be avoided in their production. 相似文献
) are subjected to mitotic or meiotic polyploidization. In developing hybrid partners, special attention is paid to resistance in addition to yield and quality characters. Early diagnoses are applied in selection so as to shorten breeding times. Somaclonal variations may occur relatively often on in vitro propagation; these need to be eliminated. Triplex and quadruplex type males are suitable for paternal hybrid partners. Strong inbreeding depressions need to be avoided in their production. 相似文献
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