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1.
阐述了甾类激素的调节基因转录活性作用和信号转导作用。  相似文献   

2.
表观遗传学使人们可以从生物学机制层面对环境影响表型的途径进行研究。通过定量分析的方法,研究了基因MLL1对可诱导转录因子NF-kappaB下游基因的调控作用,探索组蛋白H3K4甲基化酶参与基因表达的机制。结果表明,MLL1的调控主要是通过对NF-kappaB靶基因启动子进行H3K4甲基化来实现的,表观遗传学已经成为参与调节基因转录和细胞身份的关键因素。  相似文献   

3.
大学学报     
《中国科技信息》2009,(13):10-14,281-288
美洲斑潜蝇自然种群的生态控制研究;线粒体疾病与核基因-线粒体基因的表达调控;α1,2-岩藻糖转移酶基因转染对卵巢癌细胞生物学行为的影响;P-body及其与mRNA的转录后调节之间的关系;兔机械性角膜上皮损伤对结膜杯状细胞及结膜上皮细胞的作用研究  相似文献   

4.
为探索水稻响应高盐低温逆境胁迫的分子调控机制,采用Affymetrix水稻表达谱芯片,分析研究了高盐低温胁迫下水稻转录因子基因的表达谱.检测到491个差异表达的水稻转录因子基因,属于56个转录因子家族.其中17个转录因子基因,高盐低温处理后表达均显著上调,4个转录因子基因,高盐低温下表达均显著下调,9个转录因子基因经高盐、低温处理后表达水平向相反方向变化.进一步采用实时荧光定量PCR,验证了6个转录因子基因在高盐低温胁迫条件下的差异表达变化,其结果和芯片杂交结果基本一致.  相似文献   

5.
许守明  洪宪珍  王得利 《中国科技信息》2007,36(12):181-181,189
转录调控是分子生物学领域的研究热点。转录因子一般通过激活或者抑制启动子来调控基因的表达;转录抑制因子通过与特异蛋白因子或染色体部位结合来阻碍基因的活化,对转录进行负调控;而核心组蛋白的乙酰化/去乙酰化过程是调控基因活性的一个关键步骤,它在真核生物的基因转录调控中起到了很重要的作用。  相似文献   

6.
《中国科学院院刊》2009,(3):311-312
上海生科院神经科学所熊志奇研究组发现神经元电活性可以诱导CREB的转录共激活因子TORC1从胞浆穿梭到胞核,从而启动CREB下游基因的转录;而盐诱导激酶SIK,CREB的一个下游基因,则通过负反馈机制磷酸化TORC1并将其从核内排除,从而终止了CREB下游基因的转录。此项研究的意义在于为CREB介导的基因转录提供了新的机理。并且解释了CREB激活和下游基因表达在时程上的不一致性。  相似文献   

7.
核糖体在转录和翻译两个水平上调节相关基因表达,从而调控微生物的次级代谢.核糖体工程通过诱导核糖体结构的改变,从而改变其代谢产物合成的调控系统,达到改良菌株的目的.本文以rplF基因、rpsL基因、fusA基因、rpoB基因为例综述了核糖体工程的机理及其重要类型;同时通过介绍核糖体工程在抗生素产量提高、新抗生素开发、产酶能力提高、抗逆境能力改善等方面的应用,展示了其在微生物菌种改良方面的最新研究进展.  相似文献   

8.
6周大的龙葵幼苗在30 ~ 100μmoL/L CdCl2溶液中胁迫0~72 h,叶和根SOD、POD、CAT和APX活性均随Cd浓度的提高和胁迫时间的延长而上升.实时定量PCR分析表明,100μmol/L CdCl2胁迫上调幼苗叶FSD1、CSD2、POD2和CAT2与根FSD1、CSD2、POD1和APX3的转录,下调叶POD1和CAT1与根CSD1、MSD1和CAT1的转录,而对叶CSD1、MSD1、APX1和APX3与根POD2、CAT2和APX1的表达水平无明显影响.这些结果表明Cd可增强或稳定多种抗氧化酶基因的转录水平或转录后水平的调节,提高酶活性.  相似文献   

9.
次生萜类生物合成的调控   总被引:1,自引:0,他引:1  
克隆了青蒿单萜合成酶(芳樟醇合成酶)cDNA,发现该酶基因的 转录可被伤透导。在棉花悬浮细胞中,真菌激发子诱导这两个基因的转录表达。在棉芬发育 种子中,FPS基因和杜松烯合成酶基因(CAD1)随腺体的出现而大量表达,导致棉酚等倍半萜 醛类的积累。在棉花幼苗和植株中,CAD1-A和CAD1-C具有不同的表达特征。  相似文献   

10.
陈华  朱良均  闵思佳 《科技通报》2003,19(3):260-263
3种丝素基因的全序列已被测定,其中重链基因的中心区域由12个具有多态性的重复区和11个保守性较强的无定形区组成.丝素基因的表达主要在转录水平受到调控,已分离到了9种反式作用因子.丝素基因存在4种变异系统:Nd、Nd(2)、Nd-s和Nd-s^D,Nd和Nd(2)能抑制重链基因的转录,Nd-s和Nd-s^D为轻链基因的等位基因.利用同源重组技术,GFP等外源基因已被插入到家蚕重、轻链基因中.  相似文献   

11.
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.  相似文献   

12.
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.  相似文献   

13.
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.  相似文献   

14.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.  相似文献   

15.
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.  相似文献   

16.
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.  相似文献   

17.
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.  相似文献   

18.
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence  相似文献   

19.
<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese  相似文献   

20.
<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages.  相似文献   

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