AMADIS防晒服盛夏全新体验

七月,阳光炙烈,在紫外线的侵袭下,暴露在外的皮肤不仅容易产生各种色斑、皱纹,更会加速老化。暴晒还会破坏细胞与基因,受伤的细胞会释放出一种化学物质,从而刺激毛细血管,造成其破裂,也就是我们通常所说的晒红。强烈的紫外线也会破坏皮肤的DNA,使皮肤失去弹性,严重者还会引起皮肤癌。怎样才能既不暴露皮肤,又使身体保持干爽呢？阿玛迪斯防晒服带来了这一全新体验。     

基于质粒模型的DNA计算机算法求解背包问题

本研究在穷举法的背包策略的基础上借鉴二表算法的思路,应用求解最大团问题的思路计算DNA计算机的NP完全计算问题。使用这种算法,能将DNA分子计算的维数从60扩大至120,这种算法的DNA链数可达亚指数的O(1 414n),这种算法拓展了穷举法背包策略的限制,使DNA计算机NP完全问题算法优化。     

Quantitative analysis of a panel of gene expression in prostate cancer——with emphasis on NPY expression analysis

Objective： To investigate molecular alterations associating with prostate carcinoma progression and potentially provide information toward more accurate prognosis/diagnosis. Methods： A set of laser captured microdissected （LCM） specimens from 300 prostate cancer （PCa） patients undergoing radical prostatectomy （RP） were defined. Ten patients representing ＂aggressive＂ PCa, and 10 representing ＂non-aggressive＂ PCa were selected based on prostate-specific antigen （PSA） recurrence, Gleason score, pathological stage and tumor cell differentiation, with matched patient age and race between the two groups. Normal and neoplastic prostate epithelial cells were collected with LCM from frozen tissue slides obtained from the RP specimens. The expressions of a panel of genes, including NPY, PTEN, AR, AMACR, DD3, and GSTP1, were measured by quantitative real-time RT-PCR （TaqMan）, and correlation was analyzed with clinicopathological features. Results： The expressions of AMACR and DD3 were consistently up-regulated in cancer cells compared to benign prostate epithelial cells in all PCa patients, whereas GSTP1 expression was down regulated in each patient. NPY, PTEN and AR exhibited a striking difference in their expression patterns between aggressive and non-aggressive PCas （P=0.0203, 0.0284, and 0.0378, respectively, Wilcoxon rank sum test）. The lower expression of NPY showed association with ＂aggressive＂ PCas based on a larger PCa patient cohort analysis （P=0.0037, univariate generalized linear model （GLM） analysis）. Conclusion： Despite widely noted heterogeneous nature of PCa, gene expression alterations ofAM,4CR, DD3, and GSTP1 in LCM-derived PCa epithelial cells suggest for common underlying mechanisms in the initiation of PCa. Lower NPY expression level is significantly associated with more aggressive clinical behavior of PCa; PTEN and AR may have potential in defining PCa with aggressive clinical behavior. Studies along these lines have potential to define PCa-associated gene expression alterations and likely co-regulation of genes/pathways critical in the biology of PCa onset/progression.     

演示DNA分子结构模型

1特点及用途(1)特点借用宏观的具体实图模拟微观的抽象结构,使抽象形象化,微观宏观化,能科学、生动、有趣的演示DNA分子结构。(2)用途①模拟DNA分子基本单位:脱氧核苷酸(4种碱基能直观展示)。②模拟DNA分子平面结构:由2条脱氧核苷酸链反向平行排列。③模拟DNA分子立体结构:平面     

RAPD标记及其在植物育种上的应用

对RAPD标记的基本原理及其在植物育种上的应用进行了综述 ,讨论了RAPD标记的优点及局限性 ,展望了其应用前景     

制作DNA双螺旋结构模型实验材料的筛选

本文针对制作DNA双螺旋结构模型实验的不足之处,应用塑料片、纸、绳子等材料进行了对比筛选。     

简介烟草花叶病毒

1烟草花叶病毒的发现 19世纪末期人们已知有某种威胁烟草作物生存的疾病,伊凡诺夫斯基（D.I.Iwanowski）于1892年首次证明了这个病害是由滤过性病原体即病毒所引起的。斯坦利（W.M.Stanley）开始时认为病原体是蛋白质,并于1935年首先从病叶榨汁中分离到病毒状结晶,最终了解这个结晶中还含有核酸,并确定其就是病原体。烟草花叶病毒是第一个已知的病毒。     

“表观遗传”教学中几个难点的分析

分析了表观遗传机制、表观遗传信息的遗传、表观遗传与中心法则的关系、蜂王的表观遗传,为中学生物学教学提供教学背景参考与教学建议。     

运动对骨质影响的表观遗传机制研究进展

骨质变化除了与性别、年龄、激素水平、生活方式和机械受力等因素有关外,还与表观遗传调控途径有关。表观遗传调控的3大主要途径包括DNA甲基化、组蛋白修饰及非编码RNA。在遗传-环境范畴内,运动作为外源性力学刺激,可以通过调控DNA去甲基化促成骨生成,调控组蛋白修饰维持骨稳态和非编码RNA影响骨代谢通路,这些均是运动通过表观遗传途径改善骨质健康的可能机制。梳理近年来表观遗传调控在骨组织运动医学领域的研究进展,有助于为运动健骨和防治骨质疏松等代谢性疾病提供新思路。     

“DNA的粗提取与鉴定”实验的改进

针对"DNA的粗提取与鉴定"实验,虽然人教版选修1教材提供了3种可选实验方案,但没有明确具体的实验操作步骤和实验材料。教材实验方案存在操作步骤复杂,实验时间长等不足。因此,应对操作步骤和实验材料进行优化,改进二苯胺试剂的配制方法。优化改进方案可为开展该实验的课堂教学提供方法支持,也可为培养学生实验探究能力提供思考。