控制老化的基因 - Cynthia Kenyon P1
本视频由科普中国和生物医学大讲堂出品
Cynthia Kenyon (UCSF) Part 1: Genes that Control Aging
Once it was thought that aging was just a random and haphazard process. Instead, the rate of aging turns out to be subject to regulation by transcription factors that respond to hormones and other signals. In the nematode C. elegans, in which many key discoveries about aging were first made, the aging process is subject to regulation by food intake, sensory perception, and signals from the reproductive system. Changing genes and cells that affect aging can lengthen lifespan by six fold, and can also delay age-related disease, such as the growth of tumors.
来自生殖系统的信号显示衰老的规律 - Cynthia Kenyon P2
本视频由科普中国和生物医学大讲堂出品
Cynthia Kenyon (UCSF) Part 2: The Regulation of Aging by Signals from the Reproductive System
Once it was thought that aging was just a random and haphazard process. Instead, the rate of aging turns out to be subject to regulation by transcription factors that respond to hormones and other signals. In the nematode C. elegans, in which many key discoveries about aging were first made, the aging process is subject to regulation by food intake, sensory perception, and signals from the reproductive system. Changing genes and cells that affect aging can lengthen lifespan by six fold, and can also delay age-related disease, such as the growth of tumors.
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。
小熊直播第1期：如何赚取MedSci积分
欢迎收看小熊直播课堂节目，今天小熊教大家，如何在“MedSci医学”APP上来赚取积分！
除了购买积分外，总共有以下4种免费获取积分的方式哦~
一.注册即送10个积分
下载打开"MedSci医学"APP，在【我】里面，点击【立即登陆】，在登录页面选择【注册】，完成注册，即可获得10个积分。
官方下载地址：http://www.medsci.cn/m/
二.每日签到领取积分
每天，打开"MedSci医学"APP，在【我】里面，点击【签到+1积分】，即可获得1个积分。
三.资讯评论获得积分
打开"MedSci医学"APP，进入我们的【资讯】页面，评论相关资讯，即可获得2个积分。
四.分享好友送积分
打开"MedSci医学"APP，在【我】里面，点击【邀请好礼】，把里面的【邀请码】分享给好友。好友下载打开APP，输入你的验证码，你即可获得20个积分。
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/
剪接体的结构和动力学 - Melissa Moore Part 2
本视频由科普中国和生物医学大讲堂出品
本节课Melissa Moore讲述了，剪接体的成分和在每个工作周期中的剪接体。穆尔还解释了如何利用荧光蛋白标签和全反射显微镜的创新，使她和她的同事们能够更好地理解复接机器的有序组装与功能。
Melissa Moore (U. Mass/HHMI) Part 2: Spliceosome Structure and Dynamics
Moore goes on to describe the cellular splicing machine, the spliceosome, in greater detail in Part 2. She lists the components of the spliceosome and where each works in the spliceosome cycle. Moore also explains how the innovative use of fluorescent protein tags and total internal reflection microscopy has allowed her and her colleagues to better understand the ordered assembly and function of the complex splicing machine.
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/
我是如何成为一名科学家的 - Alfredo Quinones-Hinojosa
本视频由科普中国和生物医学大讲堂出品
Alfredo Quinones-Hinojosa（Q博士）（霍普金斯达大学）：我是如何成为一名科学家
出生于墨西哥的Q博士，19岁时翻越美国边界的栅栏，成为加利福尼亚的一名农场工人。由于他自己的决心，努力工作和自律，以及来自家庭和朋友的大量支持，他离开了农场工作，完成了大学和医学院的学业，最终成为一位非常成功的医生、科学家和脑外科医生。
关于讲师：Alfredo Quinones-Hinojosa是约翰霍普金斯大学，神经外科学和肿瘤学，神经系统的细胞与分子医学的副教授，脑肿瘤外科手术的主任。Q博士作为一个专家外科医生，他致力于干细胞，在脑肿瘤的病因和治疗领域的研究。
Alfredo Quinones-Hinojosa (Dr. Q) (Johns Hopkins): How I Became a Scientist
At age 19, Quiñones-Hinojosa jumped the fence from Mexico to become a farm worker in California. Thanks to his own determination, hard work and discipline and a lot of support from family and friends, he left farm work, completed university and medical school, and ultimately became a highly successful physician-scientist and brain surgeon.
About the speaker: Alfredo Quiñones-Hinojosa is an Associate Professor of Neurosurgery and Oncology, Neuroscience and Cellular and Molecular Medicine and Director of the Brain Tumor Surgery Program at Johns Hopkins University. As well as being an expert surgeon, he researches the role of stem cells both in causing brain tumors and potentially in fighting them.
This talk was first released in iBioMagazine Issue 5.
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/