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RAPD analysis of natural populations of Acanthopanax brachypus

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Cell Research 1997年第1期7卷 99-106页

作者： YAN HUA JUN SI LAN DAI NAI HU WU(Institute of Developmental Biology, Chinese Academy of Sciences, Beiling 100080) Institute of Developmental Biology Chinese Academy of Sciences Beijing 100080&#x0002A This paper is specially dedicated to Professor Lu Ji SHI on the 80th anniversary of his birthdayReceived 31March1997 Revised 23May1997 accepted 2june1997

Random Amplified Polymorphic DNA (RAPD) analysis is a new technology of molecular marking which has proved very powerful in detecting genetic diversity at the level of population. The genomic DNAs used in our experiment were extracted from fresh leaves taken from 59 individuals sampled from three natural populations in Yan An, Shanxi Province. Through more than 2,000 PCRs, deep-going RAPD analysis was carried out on DNA samples from 49 inviduals. The percentage of polymorphic RAPD loci found in these three populations were respectively 27.2 %, 18.6 % and 5.4 %; the average genetic distances within population, 0.055, 0.036 and 0.008; the average genetic distances between populations (Ⅰ-Ⅱ), (Ⅰ-Ⅲ) and (Ⅱ-Ⅲ), 0.105, 0.096 and 0.060. The genetic diversity of A. brachypus within and between populations was found, for the first time, to be rather poor,thus revealing innate factors as the cause contributing to its endangered status. In addition, our work also provides basic materials for elucidating the underlying cause of its endangerment and for its protection biology.

关键词： Acanthopanax brachypus genetic diversity random amplified polymorphic DNA(RAPD) analysis

Increment of hFIX expression with endogenous intron 1 in vitro

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Cell Research 1997年第1期7卷 21-29页

作者： ZHENG BING XIAO YUN QIU MIN TAN YONG NA XING DARU LU JING LUN XUE XIN FANG QIU(Institute of Genetics, Fudan Univerisity, Shanghai 200433) The first two authors made equally significant contributions to this work.* This paper is dedicated to Professor Lu Ji SHI on the 80th anniversary of his birthdayReceived 27September1996 Revised 21April1997 accepted 29May1997

This paper probes into the feasibility of increasing expression level of hFIX gene with endogenous nitron 1 sequence. hFIX minigene was obtained with middle sequence truncated nitron 1 inserted into the relative site of hFIX cDNA, and plasmid vector pKG5i'IX, retroviral vector GINaCi'IX were constructed. These vectors were transduced into target cells of PA317, C2C12, primary rabbit skin fibroblasts (RSF) and primary human skin fibroblasts (HSF). The expression level of mixed colonies are PA317/pKG5i'IX, 151 "g/106 cells/24h; PA317/GINaCi'IX, 308ng/106 cells/24 h; C2C12/G1 NaCi'IX, 186 ng/106 cells/24 h; RSF/GINaCi'IX, 1929 ng/106 cells/24 h; HSF/GlNaCi'IX, 1646 ng/106 cells/ 24 h. These results indicated that hFIX minigene with nitron 1 is able to increase the expression level to about 3 times of that of hFIX cDNA. Meanwhile, in order to study the application of hFIX minigene in the retroviral-mediated gene transfer system and refrain from nitron splicing during viral production, a retroviral vector GlNaCi'IXR with reversely inserted hFIX minigene expression cassette was constructed. The expression level of reverse constructor in PA317 cells was 390 ng/106 cells/24 h with 79% of bioactivity. PCR detection of HT/GlNaCi'IXR cells infected with PA317/ClNaCi'IXR supernatant confirmed the existence of nitron 1 sequence. These results suggested that expression vector with forward-inserted intronl-carrying hFIX expression cassette can be used in directed gene Human factor IX expression with nitron transfer, but when using the retroviral-mediated gene transfer system, reversely-inserted intronl-carrying hFIX expression cassette should be considered.

关键词： Intron 1 human clotting factor IX (hFIX) gene transfer gene expression reverse inserted sequence

Chromatin remodeling regulated by steroid and nuclear receptors

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Cell Research 1997年第2期7卷 127-142页

作者： ALAN P WOLFFE(Laboratory of Molecular Embroyology Nat’l Institute ofChild Health and Human Development NIH Bldg, 18T,Rm. 106 Bethesda, MD 20892-5431 USA. e-mail:awlme @helix. nih.gov) Laboratory of Molecular Embroyology Nat'l Institute of Child Health and Human Development NIH Bldg 18T Rm. 106 Bethesda MD 20892-5431 USA. e-mail: awlme@helix.nih.govReceived 27October1997 accepted 4November1997.

Coactivators and corepressors regulate transcriptionby controlling interactions between sequence-specific transcription factors, the basal transcriptional machinery andthe chromatin environment. This review consider the access of nuclear and steroid receptors to chromatin, theiruse of corepressors and coactivators to modify chromatinstructure and the implications for transcriptional *** assembly of specific nucleoprotein architectures andtargeted histone modification emerge as central controlling elements for gene expression.

关键词： Steroid receptor nuclear receptor coactitvator corepressor transcriptional activation nucleosome positioning histone modification transcriptional repression

Association of DNA with nuclear matrix in in vitro assembled nuclei induced by rDNA from Tetrahymena shanghaiensis in Xenopus egg extracts

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Cell Research 1997年第1期7卷 107-117页

作者： CHEN YING BO ZHANG XIU FEN LI ZHONG HE ZHAI(Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871) Department of Cell Biology and Genetics College of Life Sciences Peking University Beijing 100871On the occasion of Professor Lu Ji SHI's (L. C. Sze) eightieth birthday we present this paper and extend our sincere greetings to Professor SHI. As we mentioned in our paper in early 1950's it is Professor SHI who first studied the behavior of exogenous homologous desoxyribose nucleoprotein (chromatin) in amphibian eggs. His work later led to the study of nuclear assembly in cell-free system. No words can be said too much to describe Professor SHI's achievements in this field. Since the beginning of our research in this field in 1989 Professor SHI always shows high interests in our work exchanges ideas with us and encourages us. We want to express our deep indebtedness to Professor SHI for his many kindness.Received 31March1997 Revised 7May1997 accepted 6june1997

The nuclei assembled from exogenous DNA or chromatin in egg extracts resemble their in vivo counterparts in many aspects. However, the distribution pattern of DNA in these nuclei remains unknown. We introduced rDNA from the macronuclei of Tetrabymena into Xenopus cellfree extracts to examine the association of specific DNA sequences with nuclear matrix (NM) in the nuclei assembled in vitro. Our previous works showed the 5'NTS (nontranscription sequences) of the rDNA specifically bind to the NM system in the macronuclei. We show now the rDNA could induce chromatin assembly and nuclear formation in Xenopus cell-free system. When we extracted the NM system and compared the binding affinity of different regions of rDNA with the NM system, we found that the 5'NTS still hold their binding affinity with insoluble structure of the assembled nuclei in the extracts of Xenopus eggs.

关键词： Nuclear assembly nuclear matrix Xenopus egg extracts Tetrahymena rDNA

Diurnal SST warming in the Bay of Biscay:satellite measurements and model prediction

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Acta Oceanologica Sinica 1999年第2期18卷 167-176页

作者： Huang Weigen I. S. Robinson and N. C. Wells 1. Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China 2. Oceanography Department, Southampton University, Southampton SO9 5HN, UK (Received December 9, 1997 accepted june 12 Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Oceanography Department Southampton University Southampton SO9 5HN United Kingdom

NOAA AVHRR data from the Bay of Biscay between 1988 and 1990 have been examined in order to extract information on the fluctuations of sea surface temperature (SST) at the diurnal time scale. The temporal and spatial distributions of diurnal warming in the area are obtained. The diurnal warming occurs during the summer months. Large diurnal warming in excess of 1℃ is found within 100 km along the west coast of France and within 30 km along the north coast of Spain. In the central Bay of Biscay the diurnal warming is typically about 0.5℃. The diurnal warming up to 6℃ is observed occasionally in the coastal areas where the wind speed is very low. A one-dimensional oceanic mixed-layer model has been used to simulate the diurnal warming. The results demonstrate that the diurnal warming increases with the decrease of the wind speed and the increase of the net heat flux. The comparison shows that the model results are in good agreement with the satellite measurements.

关键词： Diurnal warming satellite measurements model prediction

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彩色混凝土屋面瓦发展概况

房材与应用 1997年第1期25卷 13-15页

作者：李宏魁武汉建筑材料工业设计研究院武汉市武昌东湖路5号430071

彩色混凝土屋面瓦具有多种独特的优点已逐渐被国人所接受。本文从国外形瓦的发展谈及国内彩瓦市场和建厂情况，引导投资者以平和的心态寻求一种最佳的投资方案，以期获得良好的投资及社会效益。

关键词：彩色混凝土瓦瓦混凝土屋面瓦发展市场

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