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61.
利用离体转录载体pSP18、pGEM-3Z和萤火虫荧光素酶基因(Luc)及其缺失片段构建了一组融合质粒。以这些质粒为模板,通过离体转录产生荧光素酶基因的mRNA,反义RNA及大小和结构不同的反义RNA缺失片段,再通过显微注射分别将其引入爪赡卵母细胞的细胞质。注射后的卵母细胞经一定时间培育,然后检测其翻译产物一荧光素酶的相对活性。结果表明,荧光素酶基因的表达受反义RNA及其缺失片段的严重阻抑,表达抑制和反义RNA之间存在明显的剂量效应。而且,基因表达的抑制程度主要的和反义RNA片段的结构有关。 相似文献
62.
高维空间中基于DNA计算的RNA数字编码的运算法则 总被引:5,自引:0,他引:5
随着DNA计算机的发展,用RNA代替DNA来进行大规模的计算已成为很有价值的研究课题,同时对RNA序列进行数字编码有其生物学和数学背景.RNA序列的高维空间二进制数字编码,除可以对RNA序列的碱基结构、功能基团、碱基互补、氢键强弱等性质进行编码之外,还可以方便地进行数学运算和逻辑运算.RNA序列高维空间数字编码的运算法则是:(1)根据:RNA序列数码的奇偶性质,可以推导出其与末位碱基的对应关系.当RNA序列R的数值X(R)=4n,4n 1,4n 2,4n 3时,其末位碱基依次为C,U,A,G(n=1,2,…);(2)提出RNA序列高维空间的表观维数Nn,数值维数Nx及差异维数Nd的概念.当Nd=0时,首位碱基为A或G,当Nd=2n或2n 1(n=1,2,…)时,首位碱基为C^n或(C)^nU;(3)提出RNA子序列的概念并定义RNA子序列的定值部Xi(digital value)和定位部职(location value)及其计算公式;(4)导出RNA序列的延长运算、删除运算、缺失运算、插入运算、转位运算、换位运算和置换运算等的运算法则. 相似文献
63.
64.
Cd极易被水稻等作物吸收并伴随食物链在人体内累积, 严重威胁人类健康.基于水稻Cd累积机制的现有研究, 克隆与水稻Cd累积相关的基因OsLCD和OsHMA 3, 并克隆一个维管组织特异性表达的启动子OsMTP 11 P, 利用Gateway 技术及传统酶切、连接方法, 成功构建适用于水稻等单子叶植物农杆菌转化的RNA 干扰载体pRI-M-LCD和根特异性表达载体pCB2022-H.期望通过这2个载体共转化水稻, 使大量的Cd扣留在根细胞的液泡中, 限制Cd向地上部分及籽粒中的转运, 从而实现Cd在水稻籽粒中的低累积. 相似文献
65.
INTRODUCTIONBroadbeanwiltvirus (BBWV)isthetypememberofthegenusFabavirus.Ithasawidehostrangeamongdicotyledonsandsomefamiliesofmonocotyledons,andisaneconomicallyim portantvirusinChina (Zhouetal.,1 994 ) .BBWVhasisometricparticles,hexagonalinout lineand 3 0nmindiam… 相似文献
66.
To gain better understanding of telomerase’s possible role in the carcinogenesis of gestational trophoblastic tumors, the
authors conducted RT-PCR amplification-based analysis and carried out telomeric repeat amplification to determine the levels
of the human telomerase RNA (hTR) and that of telomerase enzymatic activity itself in 43 normal human placental tissues, 35
gestational trophoblastic tumor tissues and three choriocarcinoma cell lines. hTR was expressed in malignant gestational trophoblastic
tumor tissues as well as choriocarcinoma cell lines. The results showed that hTR of early placenta villi and a part of hydatidiform
mole were positive. But relatively low levels of the hTR could be found in placental tissues. Telomerase enzymatic activity
was strongly positive in 32 of the 35 (91.4%) gestational trophoblastic tumor tissues and all the three choriocarcinoma cell
lines. The enzymatic activity of telomerase itself was detectable at relatively low lelves in 14 of the 21 (66.7%) early placental
villi, only three of the 22 (13.6%) term placenta were weakly positive. These results suggest that telomerase activity may
be correlated with the development of trophoblastic tumors, and so, may be a useful diagnostic marker for detecting the existence
of malignant trophoblastic cells.
Project (39670753) supported by NSFC 相似文献
67.
Eun-Sung Kim 《Minerva》2008,46(4):463-484
This study explores the history of nanotechnology from the perspective of protein engineering, which differs from the history
of nanotechnology that has arisen from mechanical and materials engineering; it also demonstrates points of convergence between
the two. Focusing on directed evolution—an experimental system of molecular biomimetics that mimics nature as an inspiration
for material design—this study follows the emergence of an evolutionary experimental system from the 1960s to the present,
by detailing the material culture, practices, and techniques involved. Directed evolution, as an aspect of nanobiotechnology,
is also distinct from the dominant biotechnologies of the 20th century. The experimental systems of directed evolution produce
new ways of thinking about molecular diversity that could affect concepts concerning both biology and life.
Eun-Sung Kim is currently working at the Biotechnology Policy Research Center at the Korea Institute of Bioscience and Biotechnology. His academic career has been built on risk, bioethics, and science studies associated with life science, biomedicine, and the environment. He has published in Science, Technology, and Human Values and New Genetics and Society. His current interest is in social and policy studies of technological convergence. 相似文献
Eun-Sung KimEmail: |
Eun-Sung Kim is currently working at the Biotechnology Policy Research Center at the Korea Institute of Bioscience and Biotechnology. His academic career has been built on risk, bioethics, and science studies associated with life science, biomedicine, and the environment. He has published in Science, Technology, and Human Values and New Genetics and Society. His current interest is in social and policy studies of technological convergence. 相似文献
68.
Dongxu He Aiqin Mao Chang-Bo Zheng Hao Kan Ka Zhang Zhiming Zhang Lei Feng Xin Ma 《国家科学评论(英文版)》2020,7(5):881
The aorta, with ascending, arch, thoracic and abdominal segments, responds to the heartbeat, senses metabolites and distributes blood to all parts of the body. However, the heterogeneity across aortic segments and how metabolic pathologies change it are not known. Here, a total of 216 612 individual cells from the ascending aorta, aortic arch, and thoracic and abdominal segments of mouse aortas under normal conditions or with high blood glucose levels, high dietary salt, or high fat intake were profiled using single-cell RNA sequencing. We generated a compendium of 10 distinct cell types, mainly endothelial (EC), smooth muscle (SMC), stromal and immune cells. The distributions of the different cells and their intercommunication were influenced by the hemodynamic microenvironment across anatomical segments, and the spatial heterogeneity of ECs and SMCs may contribute to differential vascular dilation and constriction that were measured by wire myography. Importantly, the composition of aortic cells, their gene expression profiles and their regulatory intercellular networks broadly changed in response to high fat/salt/glucose conditions. Notably, the abdominal aorta showed the most dramatic changes in cellular composition, particularly involving ECs, fibroblasts and myeloid cells with cardiovascular risk factor-related regulons and gene expression networks. Our study elucidates the nature and range of aortic cell diversity, with implications for the treatment of metabolic pathologies. 相似文献
69.
艾滋病是由艾滋病毒感染而引起的传染病,目前在全世界广为流行,但目前还没有彻底的根治方法。该文简要综述了RNA干扰技术在抑制艾滋病毒感染中的研究进展、存在的问题和发展前景。 相似文献
70.
浅析RNA干扰研究的进展及其应用 总被引:1,自引:0,他引:1
近年来,人类对RNA i的研究有了新突破,发现其在基因表达调控中发挥着重要的作用。文章主要对RNA i领域的研究进展做了概况性的介绍,并对该领域的未来发展方向做了猜测。 相似文献