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交互网络(Internet)的发展为联网的计算机用户之间进行信息交流提供了有效途径.就分子生物学家而言,他们不仅可以利用电子邮件系统发送和接收信息,而且更重要的是能够存取大量的分子生物学数据库和软件.利用Internet可以开展多种序列分析作业,包括序列数据库的类似性检索、基因编码区鉴定和蛋白质二级结构分析等.一个数据库,例如GenBank,可以通过多种方式来存取:a.电子邮件文件服务器,b.文件传送协议(FTP),c.Gopher,WAIS或WWW等服务器-客户机(Server-Client)系统.专为分子生物学家设计的BIOSCI电子公告牌为研究人员开展学术讨论、寻求别人帮助和与数据库人员交流提供了极大的方便.  相似文献   
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Understanding the drivers of biodiversity is important for forecasting changes in the distribution of life on earth. However, most studies of biodiversity are limited by uneven sampling effort, with some regions or taxa better sampled than others. Numerous methods have been developed to account for differences in sampling effort, but most methods were developed for systematic surveys in which all study units are sampled using the same design and assemblages are sampled randomly. Databases compiled from multiple sources, such as from the literature, often violate these assumptions because they are composed of studies that vary widely in their goals and methods. Here, we compared the performance of several popular methods for estimating parasite diversity based on a large and widely used parasite database, the Global Mammal Parasite Database (GMPD). We created artificial datasets of host–parasite interactions based on the structure of the GMPD, then used these datasets to evaluate which methods best control for differential sampling effort. We evaluated the precision and bias of seven methods, including species accumulation and nonparametric diversity estimators, compared to analyzing the raw data without controlling for sampling variation. We find that nonparametric estimators, and particularly the Chao2 and second-order jackknife estimators, perform better than other methods. However, these estimators still perform poorly relative to systematic sampling, and effect sizes should be interpreted with caution because they tend to be lower than actual effect sizes. Overall, these estimators are more effective in comparative studies than for producing true estimates of diversity. We make recommendations for future sampling strategies and statistical methods that would improve estimates of global parasite diversity.  相似文献   
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在"互联网+"教育的大力推广之下,微课、慕课、翻转课堂、手机课堂等多种教学模式应运而生。通过在生物化学课程中运用"互联网+"教学模式:教师课前准备并向学生发布相关学习资源、学生预习情况和预习效果的评价、学生成绩量化标准,取得了初步的成效。本文从我国"互联网+生物化学"教育现状、"互联网+"教育在生物化学课程中的应用以及生物化学课程与"互联网+"教育结合的未来发展等三个方面进行了阐述。  相似文献   
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目的分析互联网教育对超声专业住培医师教学的影响。方法将我科接受超声专业住院医师规范化培训的50名住培医师为研究对象,其中以2019年1~4月的住培医师为对照组,以2020年1~4月的住培医师为实验组。对照组以传统教学方式教学,实验组以互联网教学为主要教学方式,两组住培医师通过考试成绩(笔试及技能)及问卷调查方法评估不同时期超声规范化培训的教学效果结果实验组的笔试和技能考核成绩低于对照组(P<0.05),考试通过率低于对照组(P<0.05)。从两组的问卷调查结果显示,实验组的住培医师认为在激发学习兴趣、提升交流能力、提高技能操作、满意带教老师、师生互动良好5个方面的肯定评价低于对照组(P<0.05);两组住培医师在关注人文关怀、临床思维培养2个方面比较,差异无统计学意义(P>0.05);两组在培养自学能力方面的肯定评价比较,实验组明显高于对照组(P<0.05)。与对照组比较,教师对实验组的教学气氛活跃、住培医师态度积极性及检查操作规范、报告书写规范4个方面的评价较低(P<0.05);教师对两组的课程安排与进度合理性的评价无差异性(P>0.05)。结论短期研究结果显示,以互联网教学为主的教学方式对超声住培教学质量造成一定负面影响,需加以教育经验总结,为今后教学工作的改进奠定基础。  相似文献   
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To better understand factors contributing to cat adoptions, this study was used to explore a possible association between an adoptable cat's popularity on Petfinder and the cat's length of availability for adoption at a managed-intake nonhuman animal shelter. This study was also used to examine factors associated with a cat's popularity on Petfinder and the percentage of adopters who visited Petfinder before making adoption decisions. One third of adopters surveyed visited Petfinder before adopting, and half of those had viewed their adopted cats' Petfinder profiles. The number of clicks per day that cats received on the site was negatively correlated with their length of availability. Age at adoption was positively correlated with length of availability and negatively correlated with number of clicks per day. Coat color was a strong predictor of number of clicks per day and length of availability. The only variable within the photographer's control significantly associated with number of clicks per day was whether the photos included toys. Although cats' physical characteristics are strong predictors of their popularity, strategic use of toys in cats' photographs may promote adoptions of cats who are typically overlooked.  相似文献   
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发酵工程是理工科高校生物工程学科领域的核心课程之一,是一门应用性、实践性极强的专业课程。该课程传统的实践模式已无法满足当前高校对大学生工程素质教育的需求。随着信息技术、自控技术的飞速发展,多层次、跨学科的“互联网+”教学已成为现今高等教育人才培养的新模式。本文中的发酵工程实操与虚拟仿真中试实验室平台以工程学为技术手段,通过“互联网+”将虚拟现实(virtual reality,VR)技术、信息自动化控制技术、数据库与发酵过程控制有机地结合在一起,构建一个“虚实”结合的“多维”工程中试实验室平台,并以此作为抓手开展食品发酵技能训练课程工程素质教育教学的创新与探索。初步建设成果与前期教学效果表明,该实验室平台的建设对发酵工程及相关专业学生的实践动手能力有明显的提高,为后期建设积累了宝贵的经验及大量有价值的工程实训数据。  相似文献   
8.
Abstract

Gastric cancer (GC) is the second leading cause of cancer-related deaths in the world. Due to the shortage of adequate symptoms in the early stages, it is diagnosed when the tumor has spread to distant organs. Early recognition of GC enhances the chance of successful treatment. Molecular mechanisms of GC are still poorly understood. LncRNAs are emerging as new players in cancer in both oncogene and tumor suppressor roles. High-throughput technologies such as RNA-Seq, have revealed thousands of lncRNAs which are dysregulated in GC. In this study, we retrieved lncRNAs obtained by High-throughput technologies from OncoLnc database. Consequently, retrieved lncRNAs were compared in literature-based databases including PubMed. As a result, two lists, including experimentally validated lncRNAs and predicted lncRNAs were provided. We found 43 predicted lncRNAs that had not been experimentally validated in GC, so far. Further Bioinformatics analyses were performed to obtain the expression profile of predicted lncRNAs in tumor and normal tissues. Also, the roles and targets of predicted lncRNAs in GC were identified by related databases. Finally, using the GEPIA database was reviewed the significant relationship of predicted lncRNAs with the survival of GC patients. By recognizing the lncRNAs involved in initiation and progression of GC, they may be considered as potential biomarkers in the GC early diagnosis or targeted treatment and lead to novel therapeutic strategies.

Communicated by Ramaswamy H. Sarma  相似文献   
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As the importance of personalized therapeutics in aggressive papillary thyroid cancer (PTC) increases, accurate risk stratification is required. To develop a novel prognostic scoring system for patients with PTC (n = 455), we used mRNA expression and clinical data from The Cancer Genome Atlas. We performed variable selection using Network‐Regularized high‐dimensional Cox‐regression with gene network from pathway databases. The risk score was calculated using a linear combination of regression coefficients and mRNA expressions. The risk score and clinical variables were assessed by several survival analyses. The risk score showed high discriminatory power for the prediction of event‐free survival as well as the presence of metastasis. In multivariate analysis, the risk score and presence of metastasis were significant risk factors among the clinical variables that were examined together. In the current study, we developed a risk scoring system that will help to identify suitable therapeutic options for PTC.  相似文献   
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