检索结果-南通市图书馆

Identification of Nodulation Genes (nod Locus 5) From Azorhizobium caulinoaans ORS571

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 1993年第10期36卷 1177-1185页

作者：高盟生尤崇杓 K.Goethals M.Holsters Department of Biotechnology IAAE Chinese Academy of Agricultural Sciences Beijing 100094 PRC Laboratrium vor Genetica Universiteit Gent. B-9000 Gent Belgium

An 800 bp AccI-PUCII DNA containing promoter region of nodABC （Pi）from A. caulinodans ORS571 was cloned and used as a hybridization probe against the chrom（?）some DNA, which led to the identification of another 8.4-kb EcoRI fragment showing homology to P1. A corresponding clone of 8.4-kb DNA was isolated from a pLAFI gene bank （pRG90）. The restriction enzyme analysis and DNA-DNA hybridization of 8.4-kbDNA indicated the P1 homology was located in the 450-bp SmaI-SphI region （P2 region）. ω insertion deletion of 8.4 kb DNA resulted in a mutant strain ORS571-5 that delayed to nodulate the stems of S. rostrata. This phenotype was complemented by the introduction of pRK84 carrying nod locus 5 DNA.

关键词： nod gene promoter DNA-DNA hybridization ω factor.

Objective Omega vortex identification method

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2019年第3期31卷 455-463页

作者： Jian-ming Liu Yi-sheng Gao Yi-qian Wang Chaoqun Liu School of Mathematics and Statistics Jiangsu Normal University Xuzhou 221116 China Department of Mathematics University of Texas at Arlington Arlington 76019 Texas USA School of Aerospace Engineering Tsinghua University Beijing 100084 China

A new vortex identification method (Liu et al. 2016) was proposed to represent the rotation relative strength and capture and visualize the vortices in our previous study. The basic idea of the ω method is that a ratio of the vorticity squared over the summation of the vorticity squared and the deformation squared should be used to measure the relative rotation strength. However, the vorticity tensor norm is not objective. Thus, a moving observer will observe different vortex structures in a moving reference frame, which will make confusions about the real vortex structures. In the present study, by the definitions of the net spin tensor and the net vorticity vector, an objective ω vortex identification method is presented with examples to verify that the vortex structures retain in a moving reference frame.

关键词： Vortex identification the ω method objectivity turbulence visualization turbulence

MORPHOLOGICAL STRUCTURE AND FUNCTION OF AUDITORY NEURON IN BUSHCRICKET——Gampsocleis gratiosa

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1989年第16期34卷 1381-1385页

作者：沈钧贤关力 Institute of Biophysics Academia Sinica Beijing

Acoustic communication is an important way for information exchange both in animals and human species. Orthopterans can produce species-specific songs and their behavioral activities, such as mate attraction, aggression or alarm, are mediated by the songs. There-fore, the study on acoustic reception, feature extraction and processing and recognition and understanding of different songs is an advanced and important problem in the auditory neurosciences. The authors have made quantitative analyses on the acoustic behavior of

关键词： bushcricket auditory ω neuron auditory information processing

ASYMPTOTIC BEHAVIOR OF SOLUTIONS OF INITIAL PROBLEM TO SYSTEMS OF GAS DYNAMICS WITH VISCOUS TERM

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1989年第1期34卷 7-11页

作者：陆云光 Wuhan Institute of Mathematical Sciences

the existence behavior of solution has been considered in many papers. Unfortunately there are no results to the asymptotic behavior of Cauchy problem with great data. In this report, we mainly consider the asymptotic... 详细信息

关键词： Lyapunov function invariable region positive ω set.

ω-3多不饱和脂肪酸对糖尿病的影响-meta分析

在线全文

学校读者我要写书评

暂无评论

中文科技期刊数据库（全文版）医药卫生 2022年第4期 22-25页

作者：吕飞燕烟台市莱山区疾病预防控制中心山东烟台264003

系统评价ω -3多不饱和脂肪酸对糖尿病病人空腹血糖的影响。方法通过数据库共检索文献1567篇排除重复文献后确定文献1550篇。通过标题及摘要排除文献1505篇,阅读45篇文献的全文,判断文献是否符合标准阅读全文排除文献25篇收集20篇文... 详细信息

系统评价ω -3多不饱和脂肪酸对糖尿病病人空腹血糖的影响。方法通过数据库共检索文献1567篇排除重复文献后确定文献1550篇。通过标题及摘要排除文献1505篇,阅读45篇文献的全文,判断文献是否符合标准阅读全文排除文献25篇收集20篇文献的数据判断是否符合标准数据处理后排除文献10篇。结果空腹血糖(FPG)的有效量为-1.14(95%CI:-3.51至1.22,p> 0.05)。鱼油补充使相关的低密度增加脂蛋白(LDL)胆固醇水平降低了0.15(95%CI:0.02至0.29,p ω -3脂肪酸可导致有利的血脂状况,但不能改善血糖控制。

关键词： ω -3多不饱和脂肪酸糖尿病血糖血脂 meta分析

亚麻籽饲粮中添加不同水平酵母硒对蛋鸡肝脏抗氧化能力、蛋黄脂肪酸组成和蛋中硒含量的影响

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

动物营养学报 2020年第5期32卷 2138-2147页

作者：司雪阳王浩郭晓青赵青余汤超华秦玉昌张军民中国农业科学院北京畜牧兽医研究所动物营养学国家重点实验室北京100193 中国农业科学院北京畜牧兽医研究所农业农村部华北动物遗传资源与营养科学观测实验站北京100193

本试验旨在研究在亚麻籽饲粮中添加不同水平酵母硒对蛋鸡生产性能、肝脏抗氧化能力、蛋品质、蛋黄脂肪酸组成和蛋中硒含量的影响。采用单因素试验设计,选取28周龄、体重[(1.99±0.05)kg]和产蛋率[(88.42±3.57)%]接近的海兰褐蛋鸡360只... 详细信息

本试验旨在研究在亚麻籽饲粮中添加不同水平酵母硒对蛋鸡生产性能、肝脏抗氧化能力、蛋品质、蛋黄脂肪酸组成和蛋中硒含量的影响。采用单因素试验设计,选取28周龄、体重[(1.99±0.05)kg]和产蛋率[(88.42±3.57)%]接近的海兰褐蛋鸡360只,随机分为4组,每组6个重复,每个重复15只鸡。各组蛋鸡分别饲喂在含15%膨化亚麻籽基础饲粮中添加0.3(Se0.3组)、0.6(Se0.6组)、0.9(Se0.9组)和1.2 mg/kg(以硒计)酵母硒(Se1.2组)的试验饲粮。预试期2周,正试期12周。结果显示:1)在亚麻籽饲粮中添加不同水平酵母硒对蛋鸡的生产性能和蛋品质均无显著影响(P>0.05)。2)与Se0.3组相比,Se1.2组肝脏总抗氧化能力(T AOC)显著降低(Pω 3多不饱和脂肪酸(PUFA)含量均无显著影响(P>0.05),各组蛋黄中ω 3 PUFA含量均高于41 mg/g(干物质基础)。4)鸡蛋中硒含量随着饲粮酵母硒添加水平的升高而显著增加(Pω 3 PUFA同时富集于鸡蛋中的效果。

关键词：蛋鸡抗氧化能力蛋品质 ω 3 PUFA 酵母硒

Effects of Various Foods Intakes on Plasma Levels of Trans Fatty Acids in Japanese Old Men

在线全文

学校读者我要写书评

暂无评论

Food and Nutrition Sciences 2018年第7期9卷 797-805页

作者： F. Shimizu Y. Ishii M. Ogawa T. Takao S. Koba A. Takada Faculty of Life and Environmental Sciences Showa Women’s University Tokyo Japan Division of Cardiology Department of Medicine Showa University School of Medicine Tokyo Japan International Projects on Food and Health (NPO) Tokyo Japan

Background: Trans fatty acids are said to be formed by the partial hydrogenation of vegetable oils. Some amounts are produced in digestive organs of ruminants and present in dairy products or meat. In Japan, use of trans fatty acids in the foods is prohibited, thus trans fatty acids must come from foods or microbes in the digestive organs. Methods: Plasma levels of fatty acids including trans forms of healthy old men are measured by gas chromatography and correlations between various foods intakes and plasma levels of trans fatty acids such as palmitoelaidic, elaidic and linoelaidic acids are examined. Results: No correlations between various foods intakes and trans fatty acids were found except between intake of preference drinks such as tea or coffee and plasma levels of palmitoelaidic and linoelaidic acids. Conclusion: Since palmitoelaidic acid is cardioprotective, increase in plasma levels of palmitoelaidic acid may indicate that intakes of tea and coffee may be beneficial for heath by increasing palmitoelaidic acids.

关键词： Fatty Acid Trans Fatty Acid Palmitoelaidic Acid Elaidic Acid Linoelaidic Acid Saturated Fatty Acid Unsaturated Fatty Acid ω Fatty Acid DHA (Docosahexanoic Acid) EPA (Eicosapentanoic Acid) AA (Arachidonic Acid)

2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛肟的合成

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

化学研究与应用 2018年第11期30卷 1886-1891页

作者：黄静鲍涵徐铭张硕罗金岳刘祖广南京林业大学化学工程学院江苏南京210037 南京市金陵中学江苏南京210005 广西林产化学与工程重点实验室广西南宁530006

以ω-甲酰基莰烯为主原料,与盐酸羟胺、三水合乙酸钠经亲核加成反应,合成目标化合物2-(3,3-二甲基双环[2. 2. 1]庚-2-亚基)乙醛肟。采用FT-IR、GC-MS、1H NMR和13C NMR等手段对产物进行了表征,确定了产物结构。探讨了溶剂及碱的种类、... 详细信息

以ω-甲酰基莰烯为主原料,与盐酸羟胺、三水合乙酸钠经亲核加成反应,合成目标化合物2-(3,3-二甲基双环[2. 2. 1]庚-2-亚基)乙醛肟。采用FT-IR、GC-MS、1H NMR和13C NMR等手段对产物进行了表征,确定了产物结构。探讨了溶剂及碱的种类、碱的用量、物料比、反应温度以及反应时间对原料转化率、产物选择性和产率的影响,得到了适宜的工艺条件为:碱为三水合乙酸钠,n(ω-甲酰基莰烯)∶n(盐酸羟胺)∶n(三水合乙酸钠)=1. 0∶1. 2∶2. 0,溶剂为20 m L的75%乙醇,反应温度为70℃,反应时间为2. 5 h。在上述条件下,产物的产率为83. 9%。

关键词： ω -甲酰基莰烯亲核加成反应合成醛肟

Correlation of Various Foods Intakes and Plasma Levels of Omega Fatty Acids in Healthy Japanese Old Men

在线全文

学校读者我要写书评

暂无评论

Food and Nutrition Sciences 2019年第6期10卷 578-587页

作者： Akikazu Takada Fumiko Shimizu Shinji Koba International Projects on Food and Health (NPO) Tokyo Japan Faculty of Life and Environmental Sciences Showa Women’s University Tokyo Japan Division of Cardiology Department of Medicine Showa University School of Medicine Tokyo Japan

Background: Trans fatty acids are considered to impair health and some ω fatty acids are protective against atherosclerosis and diabetes mellitus. Trans fatty acids are said to be formed by the partial hydrogenation of vegetable oils. Some amounts are produced in digestive organs of ruminants and present in dairy products or meat. It is important how much these intaken fatty acids influence their plasma levels. Methods: Plasma levels of fatty acids including transforms of healthy old men are measured by gas chromatography and correlations between various foods intakes and plasma levels of trans fatty acids, and ω fatty acids are examined. Results: Intake of fish resulted in increase in plasma levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) but intake of meat such as beef, cow and chicken meat did not increase plasma levels of arachidonic acid (AA). Intakes of oils increased plasma levels of dihomo-g-linolenic acid significantly and AA to some extent. Conclusion: Plasma levels of EPA and DHA increased upon intakes of fish in Japanese old men. Oil intake but not meat intake increased DGLA significantly. These results may explain low incidence of cardiovascular diseases in Japanese people compared with American people whose plasma levels of DHA and EPA are lower.

关键词： Fatty Acid Trans Fatty Acid Palmitoelaidic Acid Elaidic Acid Linoelaidic Acid Saturated Fatty Acid Unsaturated Fatty Acid ω Fatty Acid DGLA (Dihomo-G-Linolenic Acid) DHA (Docosahexanoic Acid) EPA (Eicosapentaenoic Acid) AA (Arachidonic Acid)