自己在家中提取草莓的DNA（很有意思的科学实验）
自己在家中提取草莓的DNA（很有意思的科学实验）。来源：HadronMesons - Science and Tech
从外周血中提取Drabek基因组DNA
Drabek genomic DNA extractions from peripheral blood. Employing a novel DNA extraction procedure adapted from Drabek [Biomed. Papers 146(2), 37–39 (2002)] and Nasiri [Journal of Clinical Laboratory Analysis 19:229–232 (2005)]for human peripheral blood samples.
实验室中的温度控制：冷却保存样品
低温保存实验室样品，样本和试剂在生物医学研究实验室中会经常用到。本短片将讨论让实验室样品保持冷却的一些方法，还将阐明针对每个实验要求选择使用正确的冷却方法。例如，冰和干冰这一类冷却试剂，通常用来在实验过程中保持样品冷却。本视频讨论了最常用的冷却试剂的物理属性，以及操作使用它们时要注意的安全事项。若要在不同实验之间保存样品冷却，则需用到制冷仪器，包括实验室级别的冰箱和冻箱来对样品做长时间的保存。本视频还讨论了可用目前常用实验室制冷仪器存储的样品和试剂的类型。最后还介绍了超低温保存的概念，它是将组织，细胞和生物分子冷却到0度以下的过程，可有效终止所有降解样品的生物学反应。这里讨论了几种可以尽量减小或避免形成能造成损伤的冰晶的超低温保存方法。
实验室中的称重操作
分析天平是科研实验室中一种常见的设备。这些高度精确的仪器能够测量到万分之一克甚至十万分之一克。三梁式天平使用三梁上的平衡物来平衡托盘中的样品。而现代的分析天平使用复杂的电子传感器系统来准确地称量物质的重量。分析天平非常敏感，所以通常会有一个防风罩来防止气流对称量的干扰。称量时会使用称量船皿或者称量纸来盛装物质并保护称量盘。在称量物质之前，将称量船皿或称量纸放到托盘中然后重新调零。调零是指将天平指针调回读零的状态，这样就可准确称量物质。除了化学物质之外，分析天平还可以称量动物和昆虫，以及在超离心实验中的离心管。
端粒和端粒酶在人类干细胞和癌症中的作用 - Elizabeth Blackburn P2
本视频由科普中国和生物医学大讲堂出品
Elizabeth Blackburn (UCSF) Part 2: Telomeres and Telomerase in Human Stem Cells and in Cancer
Telomerase, a specialized ribonucleprotein reverse transcriptase, is important for long-term eukaryotic cell proliferation and genomic stability, because it replenishes the DNA at telomeres. Thus depending on cell type telomerase partially or completely (depending on cell type) counteracts the progressive shortening of telomeres that otherwise occurs. Telomerase is highly active in many human malignancies, and a potential target for anti-cancer approaches. Furthermore, recent collaborative studies have shown the relationship between accelerated telomere shortening and life stress and that low telomerase levels are associated with six prominent risk factors for cardiovascular disease.
枯草芽孢杆菌中芽孢的形成 - Richard Losick P1
本视频由科普中国和生物医学大讲堂出品
Richard Losick (Harvard) Part 1: Spore Formation in Bacillus Subtilis
How do simple cells differentiate, assemble into communities, and cope with change? Losick's seminar addresses these questions in the spore-forming bacterium Bacillus subtilis. Part I is an overview of how B. subtilis makes a spore.
在染色体分离中有关长度和数量的问题 - Richard McIntosh P1
本视频由科普中国和生物医学大讲堂出品
Richard McIntosh (U. Colorado, Boulder) Part 1: Separating Duplicated Chromosomes
The goal of these three talks is to define the problems that a cell faces as it prepares for division and to describe some of the ways it solves them. In Part 1, both the length and amount of DNA are presented as problems for chromosome segregation, particularly in eukaryotic cells. The actions of cohesins and of chromosome condensation are described as solutions. The mitotic machinery is introduced, including its diversity of form across phylogeny, however, the features that appear to be conserved are emphasized. This lecture may be useful for upper level undergraduate and graduate courses discussing mitosis and cell division. See more at www.ibioseminars.org