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1.
针对高校图书馆电子阅览室计算机系统维护过程中遇到的实际问题, 介绍了如何利用U盘量产技术构建USB-CDROM启动的WinPE维护系统。该技术不仅延伸了U盘的使用价值,还提高了电子阅览室计算机系统的维护效率。  相似文献   

2.
分析了Web of Science 2003-2012年收录的长链非编码RNAlong non-coding RNA long noncoding RNA, lncRNA)文献的发表时间、期刊分布、国家/地区分布、机构分布和学科分布,探讨了lncRNA文献的分布规律,评价了其研究阶段并预测了其未来发展,为我国lncRNA的相关研究提供参考。  相似文献   

3.
目的:系统评价脊髓型颈椎病(cervical spondylotic myelopathy,CSM)的前路手术与后路手术方式的临床效果。 方法:计算机检索Cochrane图书馆临床对照试验数据库(CENTRAL)PubMedEmbase、中国生物医学文献数据库(CBM)、中国期刊全文数据库(CNKI)、万方科技期刊全文数据库与重庆维普信息数据库(VIP)等,检索时间范围为19911月至20108月。按纳入、排除标准选择纳入脊髓型颈椎病的前路手术与后路手术方式的对照研究,评价纳入研究质量,并采用RevMan4.2进行定量分析。结果:共纳入10个对照研究。Meta分析结果表明,平均脊髓术后改善率指标的合并效应量标准化均差(SMD)0.630.19,1.06),术后并发症发生率指标的合并相对危险度(OR值)为2.40(1.15,4.37)。结论:前路手术入路途径治疗脊髓型颈椎病与后路手术入路途径相比,可提高病人平均脊髓术后功能改善率,但前路手术的术后并发症发生率要远远高于后路手术。  相似文献   

4.
目的:比较文拉法新与氯米帕明治疗抑郁症的疗效及副作用。方法:检索中国生物医学文献数据库(CBM)、中国期刊全文数据库(CNKI)及中文科技期刊全文数据库(VIP),时间截至2010531。纳入文拉法新与氯米帕明比较治疗抑郁症病人的随机对照试验。结果:共纳入16个随机对照试验,研究对象1158例。Meta分析结果显示:文拉法新与氯米帕明相比治疗病人的有效率较高[OR=1.34,95%CI(1.02,1.75)],两组病人治疗后痊愈率无统计学差异[OR=1.24,95%CI(0.97,1.58)],治疗后两组病人头晕、头痛、口干、便秘发生率差异有统计学意义,[OR=0.30,95%CI(0.19,0.49)]、[OR=0.60,95%CI(0.38,0.96)]、[OR=0.16,95%CI(0.12,0.23)]、[OR=0.21,95%CI(0.14,0.32)]。恶心呕吐发生率无统计学意义[OR=0.89,95%CI(0.56,1.41)]。结论:文拉法新治疗抑郁症有效率高于氯米帕明,头晕、头痛、口干、便秘发生率低于氯米帕明。  相似文献   

5.
通过对PubMed收录的1992-2011年骨桥蛋白(osteopontin,OPN)研究的文献计量分析,探讨了OPN研究及相关领域的发展趋势,为基础和临床研究提供有意义的参考。  相似文献   

6.
目的:通过Meta分析,进一步明确羟甲基戊二酸单酰辅酶A还原酶抑制剂(他汀)对房颤的作用,为其临床合理应用提供循证学依据。方法:检索MEDLINEEMBASECochrane Controlled Trials Register数据库,收集相关随机对照试验(RCT),进行Meta分析。结果:本文纳入20RCTs。他汀对房颤一二级预防均有显著作用(二级预防OR, 0.40; 95% CI 0.20-0.83; 一级预防OR, 0.67; 95% CI 0.51-0.88),两亚组比较并无统计学差异。阿托伐他汀亚组比其他亚组更能有效降低房颤风险(OR, 0.43; 95% CI 0.27-0.66),尤其在中小剂量亚组(OR, 0.29; 95% CI 0.19-0.45)。结论:他汀在房颤一、二级预防中均有显著作用。阿托伐他汀的抗房颤作用比普伐他汀强,且中小剂量有效性更显著。他汀的作用尚需更多的临床研究予以佐证。  相似文献   

7.
CNKI和万方数据库收录的《中华神经医学杂志》2002-2011年发表的论文为数据源进行共词分析,利用BICOMBSPSS软件研究了高频词间的关系,探讨了《中华神经医学杂志》2002-2011年的研究主题。  相似文献   

8.
通过对CNKI收录的2006-2010年图书馆学博硕士论文关键词的聚类分析,得出近几年图书馆学研究的热点,再与2002-2006年国内图书馆学研究热点和2005-2009年国外图书馆学研究热点对比,对图书馆学发展趋势做出了预测。  相似文献   

9.
概述了Google ScholarGS)学术搜索引擎的引文检索功能,并通过实例对比了GS,WS引文数据库的引文检索结果,分析了GS这一新兴学术搜索工具的引文检索功能特点和优劣,提出了其引文检索的相应改进措施。  相似文献   

10.
探讨了Web3.0环境下Lib3.0和学科馆员工作,阐述了Lib3.0环境下学科馆员的素质,提出了加强学科馆员工作的措施。  相似文献   

11.
12.
中国洁蛋生产与消费的重要性及关键加工技术   总被引:4,自引:0,他引:4  
综述了中国洁蛋生产消费的重要性研究进展,分析了洁蛋生产的现状及国外的生产情况,详细介绍了中国带壳鲜蛋的清洗、消毒、干燥、分级、涂膜保鲜等一系列的加工技术.  相似文献   

13.
【目的】通过对脆肉型梨品种‘早酥’和软肉型梨品种‘南果梨’16个部位多酚物质种类和含量的分析,揭示梨品种不同器官或组织内多酚物质组成及含量,以期找到提取多酚物质的最佳部位,为梨多酚物质的利用提供依据。【方法】以‘早酥’梨和‘南果梨’为试材,采用超高效液相色谱法测定其16个部位多酚物质的组成和含量。以熊果苷、没食子酸、原儿茶酸、新绿原酸、原花青素B1、DL-儿茶素、绿原酸、隐绿原酸、咖啡酸、原花青素B2、丁香酸、表儿茶素、原花青素C1、洋藓素、P-香豆酸、槲皮素-阿拉伯-葡糖苷、反式阿魏酸、芦丁、槲皮素-3-半乳糖苷、槲皮素-3-葡糖苷、木犀草-7-O-葡糖苷、异绿原酸B、莰菲醇-3-O-芸香糖苷、槲皮素-阿拉伯糖苷、异绿原酸A、水仙苷、异鼠李素-3-O-半乳糖苷、异鼠李素-3-O-葡糖苷、根皮苷、白藜芦醇、肉桂酸、二水槲皮素、根皮素、芹菜素和山奈黄酮醇35种多酚化合物标准品,对‘早酥’梨和‘南果梨’16个部位进行多酚的定量和定性分析。【结果】‘早酥’梨共检测到23种多酚物质,包括简单酚类2种,苯甲烯类1种,咖啡酰奎宁酸类5种,黄烷醇类5种,黄酮醇类9种和二氢查耳酮类1种;‘南果梨’共检测到21种多酚物质,包括简单酚类2种,酚酸类1种,苯甲烯类1种,咖啡酰奎宁酸类4种,黄烷醇类4种和黄酮醇类9种。‘早酥’梨16个部位以幼嫩叶片多酚含量最高,为93.82 mg·g~(-1),果肉多酚含量最低,为0.63 mg·g~(-1);熊果苷和绿原酸为各部位所共有,除果肉外,其他部位含量最高的多酚均是熊果苷,为0.08—64.86 mg·g~(-1);所检测到的6大类多酚中,每类含量最高的依次为熊果苷、丁香酸、绿原酸、表儿茶素、木犀草-7-O-葡糖苷和根皮苷,分别为403.5、0.04、79.83、16.16、9.07和0.13 mg·g~(-1);成熟叶柄所测酚种类最多为14种,木质部所测酚种类最少为3种。‘南果梨’16个部位以幼嫩叶片多酚含量最高,为104.04 mg·g~(-1),种子含量最低,为2.66 mg·g~(-1);熊果苷和绿原酸为各部位共有,除果肉和果心外,其他部位含量最高的多酚均为熊果苷,为0.87—51.75 mg·g~(-1);所检测到的6大类多酚中,每类含量最高的依次为熊果苷、原儿茶酸、表儿茶素、丁香酸、绿原酸、表儿茶素和木犀草-7-O-葡糖苷,分别为357.29、0.01、0.08、122.15、12.89和4.87 mg·g~(-1);成熟叶柄和果皮所测酚种类最多,为13种;果心所测酚种类最少,为3种。‘早酥’梨和‘南果梨’多酚含量最高的部位均为幼嫩叶片,果皮所测酚比果肉所测酚的组成及含量更丰富,花柄所测酚含量高于花,韧皮部所测酚种类和含量均高于木质部。【结论】‘早酥’梨和‘南果梨’所测酚中熊果苷和绿原酸为16个部位共有,且熊果苷是总含量最高的多酚;除根皮苷和原儿茶酸外,其他所测酚种类相同,幼嫩叶片多酚物质组成及含量均较丰富,可作为多酚提取资源进行开发利用。  相似文献   

14.
The allelopathic influence of aqueous extracts of Thymus kotschyanus on Bromus tomentellus and Trifolium repens germination (%), germination speed, and seedling growth (length, fresh and dry weight) was examined. It was noted that aqueous extracts had a considerable inhibitory effect on target plant germination, and the effect at 50%, 75%, and 100% concentration was found to be significantly higher than that at lower concentrations (5% and 25%) and control treatment (distilled water). Seedling length in addition to fresh and dry weights was also reduced significantly over control. The inhibitory effect was increased as the extract concentration was increased. B. tomentellus showed a higher sensitivity against T. kotschyanus in allelopathic effects compared to T. repens, which indicates that B. tomentellus planted in rangelands with leaf litter of T. kotschyanus will be adversely affected in terms of its germination, growth, and ultimately low forage production.  相似文献   

15.
武定鸡快慢羽纯系选育及自别雌雄效果研究   总被引:2,自引:0,他引:2  
 1992年根据武定鸡农大Ⅰ系26个父系家系6批出壳雏鸡2013只主翼羽和覆主翼羽的生长特点,将该鸡种初生雏鸡羽型分为:快羽-型、慢羽四型.表型慢羽个体占13.26%,快羽个体占86.74%,K(慢)、k(快)基因频率分别为0.0698和0.9302,经基因型测交和纯繁扩群.基本育成武定鸡快、慢羽两个纯系.用两系配套繁殖或用该鸡种的慢羽母鸡同红布罗快羽公鸡杂交,其雏鸡羽速自别雌雄的准确率平均为98.57%.  相似文献   

16.
The response of wheat varieties and breeding lines to vernalization and photoperiod in pot experiments is studied and tested by means of allele-specific markers for genes Ppd and Vrn. These markers effectively predict the degree of photoperiod sensitivity of plants to vernalization, which attests to the expediency of using them in breeding practice.  相似文献   

17.
Screening of accessions from the collection of the All-Russian Research Institute of Plant Industry for resistance to the tan spot pathogen (Pyrenophora tritici-repentis) and an evaluation of the resistance of spring and winter wheat varieties being tested at Northwest Russia state crop testing stations showed a higher frequency of resistant winter than spring varieties. Another species of the genus Pyrenophora was discovered on spring wheat in 2007, namely, Pyrenophora teres. A high correlation was found in the indices of resistance of the varieties to P. tritici-repentis and P. teres. A hybridological analysis of resistance to P. tritici-repentis revealed that in winter wheat varieties this trait is controlled by a greater number of genes than in spring wheat.  相似文献   

18.
Introduction of the FeSOD gene enhanced the stability of the photosynthetic apparatus of plants to the action of oxidative stress caused by UV irradiation. The expression of Arabidopsis thaliana FeSOD gene, targeting the enzyme in chloroplasts due to a signal sequence, leaded to significant changes in ultrastructure of cell subcompartments of tobacco and tomato leaves. The activity of superoxide dismutase in leaves of transgenic tomato plants exceeded the value of activity of this enzyme of control plants. Transgenic tobacco plants showed increasing in SOD activity compared with control non-transgenic tobacco. The activity of AP in the leaves of transgenic tobacco and tomato plants was similar with that of control non-transgenic plants, but activity of one accession of transgenic tomato, which is also characterized by high values of SOD activity, exceeded the value of control plant. Differences in ultrastructural organization of chloroplasts in the cells of transgenic and control tobacco and tomato plants have been manifested in a strong enlargement in the size of plastoglobuli. These distinctions were evident especially in the cells of the leaf parenchyma of transgenic tomato as well as transgenic tobacco. Also, a quantity of starch grains in the plastids of guard cells was increased. Chloroplasts in the cells of leaf parenchyma in transgenic plants contained less a starch grains than in wild-type plants.  相似文献   

19.
以冰糖橙和大红甜橙为材料,研究两个品种果实发育过程中有机酸和氨基酸含量的变化。结果表明,果实发育过程中大红甜橙果实柠檬酸含量、总氨基酸含量均显著高于冰糖橙;大红甜橙和冰糖橙成熟果实中氨基酸总量分别为5.06 g/100g DW和3.46 g/100g DW,以天冬氨酸、谷氨酸和半胱氨酸含量较高。果实发育过程中,谷氨酸族氨基酸在大红甜橙果实中无明显变化,而在冰糖橙果实中逐渐降低;果实发育前期天冬氨酸族氨基酸含量在大红甜橙果实中高于冰糖橙,而果实成熟期两品种无明显差异;鲜味和甜味氨基酸在大红甜橙果实中含量均高于冰糖橙,且均伴随果实成熟而降低。  相似文献   

20.
The duration of the shooting–earing period of 265 barley samples from Dagestan was studied. During the 3 years of study at the Dagestan Experimental Station of VIR (Derbent), fast-ripening samples k-15008 and k-15013 were identified. Evaluation of spring forms in the northwestern region of the country made it possible to identify sample k-15027, which had a high rate of development over 2 years. It was found that Dagestan barleys are strongly influenced by growing conditions; that is, they have a high rate of response. Vernalization temperatures, short photoperiod, and high temperatures during the growing season contribute to fast barley ripening. Using molecular markers, the allelic diversity of genes Ppd-H1 and Ppd-H2, which are involved in the control of the duration of the shooting–earing period, was investigated. Most samples of local forms of barley carry dominant allele Ppd-H2, which causes early earing under short photoperiod. Translocation of the studied barley group to unusual conditions of northwest Russia leads to significant delay in plant development.  相似文献   

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