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排序方式: 共有124条查询结果,搜索用时 31 毫秒
21.
为探讨转DREB1A基因草地早熟禾(Poa pratensis)对水分亏缺及旱后复水的生理响应,本研究选择了草地早熟禾‘巴润’品种5个转DREB1A基因株系,在光照生长室内培养12周后,进行水分亏缺及旱后复水处理,测定了草坪质量、叶片相对含水量(RWC)、叶绿素、电解质渗漏(EL)、丙二醛(MDA)、过氧化氢(H2O2)、抗氧化相关酶活性和总非结构性碳水化合物(TNC)。结果表明,转基因植株适应干旱及旱后复水的能力与抗氧化相关酶活性的增加和TNC的积累有关。 相似文献
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为了深入探索Trxs基因的功能,给转基因大麦育种提供理论依据,以啤酒大麦品种Harrington及其过量表达硫氧还蛋白S基因(Trxs)的转基因大麦株系为试验材料,对籽粒灌浆后期旗叶中还原型谷胱甘肽(GSH)含量、抗坏血酸过氧化物酶(APX)活性、叶绿素荧光特性以及不同发育阶段籽粒中GSH含量和产量性状进行研究.结果显示:(1)籽粒灌浆后期转基因大麦旗叶GSH含量与APX活性显著高于非转基因对照;(2)花后15 d时各测定时间点和籽粒灌浆后期不同测定时间转基因大麦旗叶叶绿素荧光参数Fv/Fm与Fv/Fo值普遍高于对照;(3)转基因大麦的产量性状优于对照,其千粒重、单株穗数和单株产量平均分别比对照提高了12.29%、34.34%与41.01%.这些结果表明,Trxs通过影响旗叶和籽粒中GSH含量和旗叶中APX活性,提高了籽粒灌浆后期转基因啤酒大麦抗逆境胁迫的能力,改善了啤酒大麦转基因株系在籽粒灌浆后期的光合性能,有利于提高了单株产量. 相似文献
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24-表油菜素内酯对低氧胁迫下黄瓜幼苗根系抗氧化系统的影响 总被引:5,自引:2,他引:3
【目的】探讨外源EBR(24-表油菜素内酯)对低氧胁迫下黄瓜(Cucumis sativus L.)根系的生长和抗氧化系统的影响。【方法】采用营养液水培法,以抗低氧能力较强的黄瓜品种绿霸春4号和抗低氧能力较弱的品种中农8号为材料,研究根际低氧胁迫下外源施用EBR对黄瓜根系生长、ROS及抗氧化酶活性的影响。【结果】在低氧胁迫下,EBR处理显著促进了低氧胁迫下两品种黄瓜幼苗根系生长,提高了SOD、APX、GR活性及AsA、GSH含量,降低了O 、H2O2及MDA含量。【结论】外源EBR处理通过促进低氧胁迫下黄瓜幼苗根系中抗氧化酶活性和抗氧化剂含量的提高,降低ROS含量,增强植株抗低氧胁迫的能力。 相似文献
25.
茶树花多酚粗提物分离纯化及抗氧化性 总被引:4,自引:1,他引:3
在采用超滤膜一树脂吸附乙醇一次洗脱联用技术提取茶树花多酚工艺得到粗提物的基础上,探索了不同体积分数乙醇水溶液梯度洗脱法制备高纯度茶树花多酚的方法,分离纯化得到了各洗脱物,应用HPLC法分析了各洗脱物的儿茶素的组成,并采用清除·OH及DPPH·方法比较了各洗脱物的抗氧化性能。结果表明,收集10%、20%、30%和40%乙醇洗脱液浓缩干燥后可得到得率为84.19%,质量分数为92.25%的茶多酚精制品,比一次用体积分数为70%乙醇水溶液洗脱得到多酚质量分数84.32%的样品纯度高。其中体积分数为20%乙醇的洗脱组分多酚质量分数为97.71%;各洗脱组分中不同儿茶素得到有效富集分离,它们对·OH及DPPH·清除率均呈量效关系,都高于未分离纯化的样品,其中体积分数为20%乙醇的洗脱组分中,EGCG质量分数最高为67.39%,咖啡碱得到有效去除,其对自由基清除率最高,可作为高级抗氧化剂使用。 相似文献
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27.
盐胁迫下栽培大豆黑农40不同器官中抗氧化酶活性的变化 总被引:1,自引:0,他引:1
通过对盐胁迫下栽培大豆黑农40的根、茎、叶等不同器官中主要的抗氧化酶活性的测定与分析,探讨了大豆耐盐性的机理.结果表明,黑农40叶片中的SOD、POD和APX活性水平明显高于根部和茎部.叶片中的POD和APX在高盐胁迫下的应答反应都比在低盐时快速.盐胁迫时间的延长引起根、茎、叶中的SOD和POD活性发生明显的下降,在高盐胁迫下这种下降比在低盐时更为急剧. 相似文献
28.
《Plant Production Science》2013,16(1):99-104
AbstractWe Examined The Contribution of Polyphenols To The Antioxidative Activity In The Grains of Common Buckwheat “Hitachi Akisoba” (H) and “Kanto No.1” (K) and In Those of Tartary Buckwheat “Rotundatum” (R) and “Pontivy” (P). The Antioxidative Activity In The 80% Ethanol Extracts Was 16.4 and 15.3 ?Mol-Trolox G-1 Dw In H and K, Respectively, and 52.9 and 57.4 µMOL-TROLOX G-1 Dw In R and P, Respectively. These Extracts Were Analyzed By Hplc. In Common Buckwheat, (-)-Epicatechin, (-)-Epicatechingallate, and Rutin Were Confirmed. The (-)-Epicatechin Content Was 20.2 and 15.6 Mg 100 G-1 Dw, and Those of Rutin Were 13.6 and 12.2 Mg 100 G-1 Dw In H and K, Respectively. (-)-Epicatechin Accounted For About 13 and 11% of The Total Antioxidative Activity In H and K, Respectively, and Rutin About 2% In Both Varieties. Since Each Polyphenol Accounted For Only About One Fifth of The Total Antioxidative Activity, The Existence of Unknown Antioxidants Was Suggested. In Tartary Buckwheat, Rutin Quercitrin, and Quercetin Were Confirmed. The Rutin Content Was 1808.7 and 1853.8 Mg 100 G-1 Dw, In R and P, Respectively. Rutin Accounted For About 90 and 85% of The Total Antioxidative Activity In R and P, Respectively. Accordingly, Rutin Appears To Be The Major Antioxidant In Tartary BuckwheaT. 相似文献
29.
《Communications in Soil Science and Plant Analysis》2012,43(12):1433-1444
Phosphorus (P) concentration and physiological and biochemical characteristics of the leaves of Pilea sinofasciata [both P-ME (ME) and nonME (NME)] grown in a greenhouse were determined under varying soil P conditions. Greater P concentration was observed in ME of P. sinofasciata. The concentration of chlorophyll a in the ME increased with an increase of P concentration in soil, whereas the reverse tendency was observed in the NME. A slight decrease of chlorophyll b concentration existed at 100 mg P kg?1 soil for ME. Pilea sinofasciata of ME growing under high P concentration presented greater bioactivities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) and less concentrations of malondialdehyde (MDA) and free proline than under low-P conditions, whereas the opposite tendency was manifested in the NME, which demonstrated normal growing status and steady accumulation efficiency. 相似文献
30.
Hideo Ohashi Tetsuya Kyogoku Takahiro Ishikawa Shin-ichiro Kawase Shingo Kawai 《Journal of Wood Science》1999,45(1):53-63
The present work was undertaken from the standpoint of radical-capturing ability with regard to the antioxidative ability of flavonoids, especially flavonols distributed widely in woody plants. In regard to the flavonols, six methyl derivatives were initially prepared from quercetin and its litinoside. Their radical-capturing constants were determined strictly by the stopped-flow spectroscopic method. It was proved that the radical-capturing ability of quercetin mainly involves the vicinal C3. and C4, hydroxyl groups and the C3 hydroxyl group. To clarify the reaction mechanism begun at the C3 hydroxyl group of quercetin, 5,7,3,4-tetramethylquercetin (TMQ), flavon-3-ol (F30) and so on were treated with 2,2-azo-bis-(2,4-dimethylvaleronitrile) (AMVN). Six products (1–6) containing one depside and its two hydrolytic products, two valeronitrile adducts, and others were isolated from the reaction mixture of TMQ and their structures determined by instrumental analyses. Similarly, F30 gave four products, 7–10, which corresponded to the above products 1–3 and 5 (one depside, its two hydrolytic products, and one adduct), respectively. 3,5,7,3,4-Pentamethylquercetin (PMQ) and flavon-3-O-methylate (F3M) gave no products. The quantitative change of the products with reaction time was determined spectroscopically. An initial reaction pathway for the radical-capturing reaction of flavon-3-ols with AMVN was proposed based on the products and their amounts. The main route — formation of depside and its hydrolytic products via ketohydroperoxide (3) or ketohydroperoxy radical (4) - was similar to that of the oxidation reaction of quercetin with quercetinase and light.Part of this paper was presented at the 46th and 47th annual meetings of the Japan Wood Research Society, Kumamoto and Kouchi, April 1996 and 1997 相似文献