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1.
Seligson DB  Horvath S  Shi T  Yu H  Tze S  Grunstein M  Kurdistani SK 《Nature》2005,435(7046):1262-1266
Aberrations in post-translational modifications of histones have been shown to occur in cancer cells but only at individual promoters; they have not been related to clinical outcome. Other than being targeted to promoters, modifications of histones, such as acetylation and methylation of lysine and arginine residues, also occur over large regions of chromatin including coding regions and non-promoter sequences, which are referred to as global histone modifications. Here we show that changes in global levels of individual histone modifications are also associated with cancer and that these changes are predictive of clinical outcome. Through immunohistochemical staining of primary prostatectomy tissue samples, we determined the percentage of cells that stained for the histone acetylation and dimethylation of five residues in histones H3 and H4. Grouping of samples with similar patterns of modifications identified two disease subtypes with distinct risks of tumour recurrence in patients with low-grade prostate cancer. These histone modification patterns were predictors of outcome independently of tumour stage, preoperative prostate-specific antigen levels, and capsule invasion. Thus, widespread changes in specific histone modifications indicate previously undescribed molecular heterogeneity in prostate cancer and might underlie the broad range of clinical behaviour in cancer patients.  相似文献   

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评价近20多年来(1992—2016)中国儿童精神发育迟滞(Mental retardation,MR)发病状况与病因,为MR预防和干预提供基础资料。以精神发育迟滞或智力低下为关键词,以风险因素和病例-对照为联合关键词,检索中国期刊全文数据库、维普数据库和万方数据库有关MR的研究论文。对筛选的文献,采用Revman软件(version 5.0)合并分析筛选出的数据。共纳入相关文献486篇,按照标准筛选出15篇文献,涉及MR儿童7329例,正常对照7511例。数据分析结果表明,在发病风险因素中,新生儿体重低下、MR家族史和早产具有异质性,而产时窒息和父母近亲结婚具有较高的一致性。Meta分析显示MR各因素合并比值依次为:MR家族史(9.90)、产时窒息(7.73)、父母近亲结婚(6.36)、难产(5.60)、早产(4.36)和出生时低体重(3.08)。近20多年来,中国儿童MR发生影响因素中,家族性遗传仍然是高风险因素,提示积极开展遗传咨询和指导有助于降低MR的发生;其次,产时因素是另一大类风险因素,提高医务人员素质,增强育龄夫妇保健意识,加强围产期孕妇的监护,将会有效降低后天因素导致MR的发生。  相似文献   

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Germline transmission of genetically modified primordial germ cells   总被引:3,自引:0,他引:3  
Primordial germ cells (PGCs) are the precursors of sperm and eggs. In most animals, segregation of the germ line from the somatic lineages is one of the earliest events in development; in avian embryos, PGCs are first identified in an extra-embryonic region, the germinal crescent, after approximately 18 h of incubation. After 50-55 h of development, PGCs migrate to the gonad and subsequently produce functional sperm and oocytes. So far, cultures of PGCs that remain restricted to the germ line have not been reported in any species. Here we show that chicken PGCs can be isolated, cultured and genetically modified while maintaining their commitment to the germ line. Furthermore, we show that chicken PGCs can be induced in vitro to differentiate into embryonic germ cells that contribute to somatic tissues. Retention of the commitment of PGCs to the germ line after extended periods in culture and after genetic modification combined with their capacity to acquire somatic competence in vitro provides a new model for developmental biology. The utility of the model is enhanced by the accessibility of the avian embryo, which facilitates access to the earliest stages of development and supplies a facile route for the reintroduction of PGCs into the embryonic vasculature. In addition, these attributes create new opportunities to manipulate the genome of chickens for agricultural and pharmaceutical applications.  相似文献   

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酸雨的形成与危害   总被引:1,自引:0,他引:1  
从地理和化学的角度论述了酸雨形成的过程及影响酸雨形成和分布的自然因素,阐明了酸雨对环境的危害,以及防治酸雨的措施.  相似文献   

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在不确定条件下,经济过程中不同主体由于所拥有的资源和对风险偏好态度不同而产生不同的决策行为。以参加保障者在不确定经济风险条件下的效用函数为研究内容,通过引入无差异曲线,并证明引入的无差异曲线是效用函数值的消费束集合,求得最优解以提供在不确定风险条件下参保主体和政府对经济风险保障的偏好分析,构造参保主体效用最大化的选择方程,为参保主体和政府在进行保障项目的设置和实施中的决策行为提供参考基础。  相似文献   

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残留农药污染危害及其防治   总被引:16,自引:0,他引:16  
农药、化肥是目前农业增产的主要依靠,由其引起的残留污染对人的健康危害已上升为重要问题,只有在政府的倡导下,科学工作者的努力下,公众的支持和参与下,方可逐步降低农药残留污染,改善环境,提高人类健康水平。  相似文献   

9.
微波的危害及微波防护膜的研究   总被引:1,自引:0,他引:1  
从近期的国内外研究报告看出,人们对微波生物效应有了新的认识。为了消除微波对人体辐射的不良影响,笔研究了有效的防护措施,提出一种由微波吸收材料和微波反射材料组成的防护膜,设置在微波源与保护主体之间。经实验测得手机上采用微波防护膜后,防护区域微波射场强可降至5μW/cm^2以下,符合国家的卫生标准,有效地多功能解决了微波辐射的危害问题。  相似文献   

10.
从内因、外因两方面论证了湖北师范学院体育系增设社会体育本科专业的必要性和可能性,认为湖北师范学院体育系增设社会体育专业不仅必要,而且可行。  相似文献   

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电磁辐射污染直接威胁人体健康。本文对电磁辐射污染的分类 ,对人体健康的危害及防治措施进行了论述  相似文献   

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[目的]探究风险规避、社会网络对农地转出契约期限的影响,以此了解农户地转出契约期限决策以及促成更多的农地长期流转.[方法]提出研究假设并利用中国家庭金融调查(CHFS)2015数据进行实证检验,实证研究中利用Logit模型进行基准回归,并采用Probit模型、OLS模型和异质性检验等方法进行稳健性检验.[结果]风险规避...  相似文献   

13.
黄山  刘洋  沈思 《工程与建设》2011,25(1):69-71
近年来地震对人类的危害变得越来越大,做好建筑物震害预测工作具有非常重要的现实意义,尤其是目前城市中一些旧的多层砖混结构房屋,其抗震能力较差.为了较好的预测多层砖混结构房屋的震害,该文采用结构易损性分析方法对该类房屋的未来震害进行了预测分析,对今后进行抗震防灾规划和震害预测工作具有一定的参考意义.  相似文献   

14.
浅谈铅的污染及对人的危害   总被引:7,自引:0,他引:7  
林丹 《新余高专学报》2006,11(2):109-110
铅广泛应用于人们的生产、生活领域,但铅又是一种极具污染性的物质。它通过在环境和人体中的循环,对人体的神经系统、血液系统及其它方面产生毒害作用。铅对人体的危害主要有环境类、职业类、生活类、药物类、母源类五种方式。  相似文献   

15.
与传统智力理论不同,情绪智力强调能力的情绪因素。戈尔曼的研究动机在于运用情绪智力概念去解释个体的绩效和成功。研究发现,管理者的情绪智力是管理绩效的重要影响变量。管理者进行成功管理,应从自我情绪意识、自我情绪调控和激励、"情感移入",以及协调人际关系4个方面来提升情绪智力。  相似文献   

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六氟化硫气体的危害与预防   总被引:1,自引:0,他引:1  
六氟化硫(SF6)具有优异的绝缘和灭孤性能,被广泛应用于高压电器设备的生产和使用中,但由于各种原因,导致SF6气体及其在高温电弧作用下产生的有毒分解物排放到大气中,这不仅污染环境,同时也给电器设备的正常运行和人们的身体健康带来了不利影响.探讨了减小或消除这种危害的合理措施.  相似文献   

18.
V Lindgren  M Ares  A M Weiner  U Francke 《Nature》1985,314(6006):115-116
U2 RNA is one of the abundant, highly conserved species of small nuclear RNA (snRNA) molecules implicated in RNA processing. As is typical of mammalian snRNAs, human U1 and U2 are each encoded by a multigene family. In the human genome, defective copies of the genes (pseudogenes) far outnumber the authentic genes. The majority or all of the 35 to 100 bona fide U1 genes have at least 20 kilobases (kb) of nearly perfect 5' and 3' flanking homology in common with each other; these U1 genes are clustered loosely in chromosome band 1p36 (refs 5, 7) with intergenic distances exceeding 44 kb. In contrast, the 10 to 20 U2 genes are clustered tightly in a virtually perfect tandem array which has a strict 6-kb repeating unit. We report here the assignment, by in situ hybridization, of the U2 gene cluster to chromosome 17, bands q21-q22. Surprisingly, this region is one of three major adenovirus 12 modification sites which undergo chromosome decondensation ('uncoiling') in permissive human cells infected by highly oncogenic strains of adenovirus. The two other major modification sites, 1p36 and 1q21, coincide with the locations of U1 genes and class I U1 pseudogenes, respectively. We suggest that snRNA genes are the major targets of viral chromosome modification.  相似文献   

19.
谐波的危害及治理   总被引:1,自引:0,他引:1  
随着电力电子技术的广泛应用、家用电器的普及、工业用炼钢电弧炉的发展等,大量具有非线性、冲击性以及不平衡的用电特性的电力电子设备接入电网使得电力系统电压及电流波形发生严重的崎变,这就是通常所说的谐波。文章就谐波对供电线路、电力设备、用电设备、弱电系统以及人体产生的危害和影响,谐波治理的标准、谐波治理的措施等作了完整的分析阐述。  相似文献   

20.
通过WGD-8A光栅光谱仪采集光谱,对市面上最常见和使用最广泛的照明光源(节能灯)进行光谱测量,并进行分析;根据不同特征的光谱,找出其中起主要作用的成分,分析其对人体(尤其是人眼)的影响,并尽可能提出相应的解决方法,以寻找对人体最无害的理想光源。结果显示,在众多的节能灯品牌中,Philips节能灯性能出众。  相似文献   

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