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
通过实验了解有丝分裂 - Richard McIntosh P2
本视频由科普中国和生物医学大讲堂出品
Richard McIntosh (U. Colorado, Boulder) Part 2: Understanding Mitosis through Experimentation
The second lecture describes some key experiments showing the dynamics of a formed mitotic spindle and the ways these may contribute to accurate chromosome motion. Experiments that reveal aspects of the processes by which chromosomes attach to the spindle are presented. Mitotic motors are introduced and discussed in the light of what they probably do and do not accomplish to effect chromosome motion, including acting to improve the accuracy of chromosome segregation. See more at http://www.ibioseminars.org
有丝分裂后期：染色体向纺锤体两极移动 - Richard McIntosh P3
本视频由科普中国和生物医学大讲堂出品
Richard McIntosh (U. Colorado, Boulder) Part 3: Moving Chromosome to the Spindle Poles: Anaphase A
The third lecture presents evidence, largely from McIntosh's lab, that shows how microtubule depolymerization can move chromosomes in vitro and explores the nature of some of the protein complexes that can couple chromosomes to microtubules and take advantage of this reaction. See more at http://www.ibioseminars.org
免疫反应的细胞基础 - Ira Mellman P1
本视频由科普中国和生物医学大讲堂出品
Ira Mellman (Genentech) Part 1: Cellular Basis of the Immune Response
The immune system is charged with protecting us from invading microorganisms, a task that falls to a complex array of highly specialized cell types spread throughout the body but that must work together as an integrated system. How they accomplish and perform their functions can be wonderfully understood by probing the basic mechanisms governing their activities. In the first video, we will consider the overall organization of the immune response in cellular terms, the innate immune system (comprising evolutionarily ancient phagocytic cells that recognize conserved molecules of microorganisms) and the adaptive immune system (composed of lymphocytes that recognize chemically diverse antigens).
基因分裂和RNA剪接 - Melissa Moore P1
本视频由科普中国和生物医学大讲堂出品
Melissa Moore (U. Mass/HHMI) Part 1: Split Genes and RNA Splicing
In the first part of her talk, Dr. Moore explains that eukaryotic pre-mRNA contains long stretches of non-protein coding sequences interspersed with protein coding regions. By recognizing specific sequences, cellular machinery splices out the non-coding introns leaving just the protein-coding exons in mRNA. Although at first glance this may seem like a wasteful process, it is splicing that facilitates the evolution of new genes, and alternative splicing that allows a limited number of genes to produce a large number of proteins.
病毒包膜的内吞和渗透作用 - Ari Helenius P2
本视频由科普中国和生物医学大讲堂出品
Ari Helenius (ETH Zurich) Part 2: Endocytosis and Penetration
In the second lecture, the next steps in viral infection are described. Endocytosis of plasma membrane bound viruses can occur via a number of mechanisms including caveolar, clathrin, non-clathrin, or lipid raft mediated pathways. The internalized virus is enclosed in an endosome that may undergo increasing acidification resulting in acid mediated fusion between the viral envelope and the vesicle membrane. Following membrane penetration, the virus, once again, makes use of cellular machinery such as microtubules and their motors, to transfer its genome to the nucleus. Helenius describes experiments from his lab and others that have deciphered these complex processes.
用SDS-PAGE技术分离蛋白
十二烷基硫酸钠聚丙烯酰胺凝胶电泳，也称SDS-PAGE，是一种被广泛使用，仅根据分子量大小来分离蛋白质混合物的技术。阴离子去污剂SDS，在变性的线性蛋白表面沿长度均匀分布使其带电。将它们上样到聚丙烯酰胺凝胶后，施加电压，这些表面覆盖SDS的蛋白将被分开。电场作为驱动力，牵引SDS结合的蛋白朝阳极移动，分子量大的蛋白将比小的蛋白移动慢。为了判断蛋白的大小，已知分子量大小的蛋白质标准也会和样品一起上样并在同等条件下跑胶。
本短片介绍SDS-PAGE技术,首先将解释其背后的原理，然后演示每一步的操作过程。视频还将讨论实验中的各种参数，如聚丙烯酰胺浓度，和用于跑胶的电压。还会介绍电泳之后的考马斯亮蓝和银染色方法，以及其他电泳技术，如双向凝胶电泳。
Tagrisso的伴随诊断 - 陈巍学基因(31)
欢迎来到【陈巍学基因】。我们这个节目，主要是介绍基因组学，和临床分子诊断的最新技术进展。
今天，会和大家谈一谈阿斯利康在开发Tagrisso这个新药过程中对4种伴随诊断方法的研究结果。
Tagrisso是阿斯利康公司开发的一个针对EGFR基因有耐药突变的晚期非小细胞肺癌者的药物，是酪氨酸激酶抑制剂类的靶向抗癌药物。
Tagrisso可以选择性地抑制突变型的EGFR，对发生耐药的肿瘤有强抑制作用；而对野生型的EGFR的抑制作用较弱，即对身体正常表皮细胞的生长抑制作用较弱。
下载生物谷APP，观看行云学院视频，让播放更流畅，使用更快捷！
生物谷APP，每天都有新资讯，每天都有好视频！
官方下载地址：http://www.medsci.cn/m/
核酸性酶的发现 - 托马斯·罗伯特·切赫
本视频由科普中国和生物医学大讲堂出品
托马斯·罗伯特·切赫，在本次讲座中讲述了他那令人激动的实验，如何发现RNA可以催化来切割和连接生成化学键。在此之前发现，大多数科学家认为，只有蛋白质可以进行催化的生物反应。这项工作的重要性已被公认的1989诺贝尔化学奖。
下载生物谷APP，观看行云学院视频，让播放更流畅，使用更快捷！
生物谷APP，每天都有新资讯，每天都有好视频！
官方下载地址：http://www.medsci.cn/m/
抗原提呈和树突状细胞 - Ira Mellman Part 2
本视频由科普中国和生物医学大讲堂出品
早在100多年前，科学家就已经发现，免疫反应是由先天性和适应性免疫两个系统构成。而负责连接这两部分免疫反应的细胞类型，是最近才发现的树突状细胞。树突状细胞具有检测保守微生物产物的能力，可以激活细胞的先天免疫反应，并捕捉到广泛多样的微生物抗原抗体，也可以激活适应性免疫反应。抗原提呈和树突状细胞的独特能力，反映了细胞生物学的一系列显著的特化作用。
Ira Mellman (Genentech) Part 2: Antigen Presentation and Dendritic Cells
The immune response integrates two distinct systems of innate and adaptive immunity discovered over 100 years ago. Linking these two arms of the immune response is the task of a comparatively recently identified cell type, the dendritic cell. Dendritic cells have the capacity to detect the conserved microbial products that activate cells of the innate immune response and capture the dramatically wider diversity of microbial antigens to prime antibody and T cell responses characteristic of adaptive immunity. The unique capacity of dendritic cells for antigen processing and presentation reflects a series of remarkable specializations of basic principles of cell biology.
下载生物谷APP，观看行云学院视频，让播放更流畅，使用更快捷！
生物谷APP，每天都有新资讯，每天都有好视频！
官方下载地址：http://www.medsci.cn/m/