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1.
探讨目前流行的3种网络信息交流工具——博客、微博和微信,比较分析其在医院图书馆发展中的作用及其特征。指出医院图书馆应根据自身需要应用这些交流工具开展相应服务,为用户搭建互动交流平台,促进服务质量的提高。 相似文献
2.
以浙江省首届“云馆配”图书展示会为例,介绍了“云馆配”采访模式的具体实践,对“云馆配”与现场采访、征订目录采访、读者荐购、读者决策采购等不同采访模式进行了比较,指出了各种模式的优势与不足,提出了“云馆配”采访模式的优化发展策略。认为“云馆配”立足用户需求,不仅使图书馆(用户)、馆配商、出版社三方得到了及时、有效的沟通,还成为读者决策采购的一种新的积极尝试。“云馆配”采访模式已在疫情期间得到了较好应用,未来可辅助日常图书采访。 相似文献
3.
Contemporary analytical methods have the sensitivity required for Ochratoxin A detection and quantification, but direct application of these methods on real samples can be rarely performed because of matrix complexity. Thus, efficient sample pre-treatment methods are needed. Recent years have seen the increasing use of artificial recognition systems as a viable alternative to natural receptors, because these materials seem to be particularly suitable for applications where selectivity for Ochratoxin A is essential. In this review, molecularly imprinted polymers, aptamers and tailor-made peptides for Ochratoxin A capture and analysis with particular attention to solid phase extraction applications will be discussed. 相似文献
4.
Molecular analysis of bacteria in asymptomatic and symptomatic endodontic infections 总被引:4,自引:0,他引:4
The purpose of the present study was to use terminal restriction fragment length polymorphism analysis and the 16S rRNA gene clone library to investigate the diversity of the microbiota associated with asymptomatic and symptomatic endodontic infections and to compare the bacterial community structure in these two clinical conditions. Samples were taken from asymptomatic endodontic infections associated with chronic periradicular lesions and from symptomatic infections clinically diagnosed as acute abscesses. 16S rRNA genes from DNA isolated from clinical samples were used to construct clone libraries or were subjected to terminal restriction fragment length polymorphism analysis. Sequence analysis of 186 clones revealed 42 taxa; 23 (55%) were uncultivated phylotypes, of which seven were unique to endodontic infections. Clone sequencing and terminal restriction fragment length polymorphism analysis revealed that the most commonly detected taxa were Fusobacterium nucleatum (including terminal restriction fragment types 1 and 2), Peptostreptococcus micros/Peptostreptococcus sp. oral clone AJ062/BS044/FG014, Prevotella species, Dialister species, Mogibacterium species, Lachnospiraceae oral clone 55A-34, Filifactor alocis, Megasphaera sp. oral clone CS025/BS073, and Veillonella sp. oral clone BP1-85/Veillonella dispar/V. parvula. Bacteroides-like sp. oral clone X083/Bacteroidales oral clone MCE7_20 and Dialister sp. oral clone BS016/MCE7_134 were detected only in asymptomatic teeth. On the other hand, F. nucleatum terminal restriction fragment type 2, Prevotella intermedia, Dialister pneumosintes, and some phylotypes were exclusively detected in symptomatic samples. Bacterial profiles of symptomatic endodontic infections generated by terminal restriction fragment length polymorphism analysis were clearly different from those of asymptomatic infections. Overall, the average number of terminal restriction fragments in symptomatic samples was significantly larger than in asymptomatic samples. Molecular analysis of the microbiota associated with symptomatic or asymptomatic endodontic infections indicates that the endodontic bacterial diversity is greater than previously described by culture methods and that the structure of the microbiota differ significantly between asymptomatic and symptomatic infections. 相似文献
5.
目的 :N -乙酰氨基葡糖苷酶 (N -acetylglucosaminidase)是链球菌gordonii六种胞外糖苷酶之一。为研究该酶 ,克隆和表达该基因片段。方法 :将链球菌gordoniiFSS2染色体DNA分离提纯 ,用限制性内切酶Sau 3AI不完全酶切 ,产生长度不等的随机片段 ,琼脂糖凝胶电泳分离和回收 2 - 8kpb的随机片段 ,然后与BamHI线性化及 5’端脱磷处理的载体pUC 18连接 ,转化大肠杆菌XL1-Blue;β—半乳糖苷酶筛选系统及酶切 ,检测插入片段。根据N -乙酰氨基葡糖苷酶与特异人工底物X -GlucNac反应 ,有色物质X被释放原理 ,筛选表达克隆。结果 :共有 6×10 6个转化子 ,约 5 0 %转化子含有插入片段 ;检测到 8个N—乙酰氨基葡糖苷酶表达克隆。结论 :所构建的基因组文库具有完整性 ,该基因在大肠杆菌XL1-Blue中成功表达。 相似文献
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7.
随着医药领域对靶向调节特定生命活动过程的新分子化合物的需求日益增加,高效、低成本地发现亲和配体分子的新型小分子药物筛选技术——DNA编码的化合物库(DNA encoded compound library,DEL)筛选技术应运而生。DEL作为组合化合物库,可以是简单小分子化合物的集合,也可以是具有高级空间结构的复杂小分子库,每个化合物都以共价方式与特异的DNA序列偶联,因而可将库中所有化合物与靶标蛋白进行合并筛选,随后使用高通量测序对DNA编码序列进行测序来鉴定结合的配体分子。近年来,应用DEL技术筛选开发候选药物的例子已越来越多地被报道,本文回顾和总结了DEL技术的实施流程,特别是DEL库构建和亲和筛选方法的最新研究进展,展示了利用DEL技术筛选开发的最新亲和配体分子,并对DEL技术在生命科学领域的应用前景作了展望。 相似文献
8.
国际社会对传统知识的获取缺乏完善的管理制度与措施,菲律宾的健康传统知识数字图书馆在保护传统知识方面起到了重要防御作用.本文从基本情况、信息来源、主要内容及法律保障4个方面对健康传统知识数字图书馆进行系统分析,希望为中医药传统知识保护提供借鉴、启示与参考. 相似文献
9.
《Health & place》2019
In considering the influence of the neighborhood environment on cognitive function, little research has looked beyond the individual factors. Here, we conducted a study on 21,008 older adults aged 65 years and above in Hong Kong to examine the cross-sectional associations of neighborhood economic disadvantage, recreational resources, walkability, library accessibility and physical activities on cognitive function and dementia. Both smaller and larger census tracts were adopted as proxies for neighborhoods. Using multilevel regression, neighborhood economic disadvantage was found to be associated with cognitive decline, net of individual features. This association was not explained by neighborhood built environment. Recreational environment was not a significant factor for older adults' cognitive function while library accessibility was. Neighborhood walkability was only related to dementia but not the cognitive function score. Physical activity can partly explain the relationship between neighborhood environment and cognitive function. No significant interaction effect was identified except on the educational level and neighborhood library accessibility. To conclude, late life residential environments are important contexts for aging. Aging-in-place interventions in Hong Kong should thus address neighborhood poverty, improve accessibility of libraries and walkability to reduce future risks of cognitive decline. 相似文献
10.
Microscale Adaptation of In Vitro Transcription/Translation for High‐Throughput Screening of Natural Product Extract Libraries 下载免费PDF全文