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Estimates of Autumntime Benthic Secondary Production in Laizhou Bay and Adjacent Bohai Sea Waters

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Journal of Ocean University of China 2010年第3期9卷 279-285页

作者： HUA Er zhou hong ZHANG Zhinan yu Zishan ~ College of Marine Life Science Ocean University of China Qingdao 266003 P. R. China

The whole metazoan community inhabiting Laizhou Bay and adjacent Bohai Sea waters were sampled in late autumn, 2006. Secondary production estimates for macrofauna and meiofauna were made separately. Total benthic secondary production was as high as 8.38 ±4.08 g ash-free dry weight （AFDW） m^-2 a^-1, which represented the autumn production level. In general, macrofaunal secondary production in Laizhou Bay was much lower than that in adjacent Bohai Sea areas. In contrast, meiofaunal secondary production in Laizhou Bay was higher than that in adjacent Bohai Sea areas. Macrofatma contributed 61% to benthic secondary production （5.09 ±3.26 g AFDW m^-2 a^-1）, lower than the value in previous studies in Bohai Sea. Sediment granulometric characteristics and bottom-water salinity could explain the substantial variability in the macrofauna biomass and production. Meiofaunal production was an important component of benthic production and exceeded macrofauna production under exceptional conditions, e.g. in Laizhou Bay, where macrofauna was restricted. Chlorophyll pigments （Chl-a） concentrations in sediment explained the general meiofaunal biomass and production distribution here.

关键词： benthic secondary production meiofauna macrofauna Laizhou Bay the Bohai Sea

Separation and Bio-activities of Spirostanol Saponin from Tribulus terrestris

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Chemical Research in Chinese Universities 2010年第6期26卷 915-921页

作者： ZHANG Shuang YANG Rui-jie LI hong YIN Zong-yuan zhou hong-yu LI Xu-wen JIN Yong-ri YANG Shi-jie Norman Bethune College of Medicine Jilin University Changchun 130021 P. R. China College of Chemistry Jilin University Changchun 130012 P. R. China

Gross saponins of Tribulus terrestris（GSTT） have exact effect on cardiovascular and cerebrovascular *** as a mixture,the specific efficient component of GSTT is still *** monomers of spirostanol saponins were isolated and idendified as JA―JI（named transitorily） by means of NMR *** bio-activity screening on them,we defined that monomers tigogenin 3-O-β-D-xylopyranosyl（1→2）-[β-D-xylopyranosyl（1→3）]-β-D-glucopyranosyl（1→4）-[α-L-rhamnopyranosyl（1→2）]-β-D-galactopyranoside（compound JB） and hecogenin3-O-β-D-glucopyranosyl（1→4）-β-D-galactopyranoside（compound JG） have cytoprotective *** JB display effective dose in 10-8 and 10-9 mol/L,and JG in 10-6―10-9 mol/*** rate,lactate dehydrogenase（LDH） and apoptosis also show that JB（at dose 10-8,10-9 and 10-10 mol/L） can protect myocardial injury caused by hypoxia/reoxygenation（H/R）.While morphology change also shows JG has cytoprotective bio-activity.

关键词： Tribulus terrestris Spirostanol monomer Bio-activity Cytoprotective

Determination of Saponins in Leaf of Panax Ginseng C. A. Mey. by High Performance Liquid Chromatography

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Chemical Research in Chinese Universities 2009年第3期25卷 297-301页

作者： LIU Gui-ying zhou hong-yu LU Juan ZHU Na GUI Ming-yu JIN Yong-ri ZHANG Yi-hua WANG Xin LI Xu-wen Department of Analytical Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China Department of Radiation Medicine School of Public Health Jilin University Changchun 130021 P. R. China

A high performance liquid chromatography（HPLC） with UV detection was established for simultaneous determination of saponins in the leaf of Panax ginseng C. A. Mey. Nine ginsenosides（Rbl, Rb2, Rb3, Rc, Rd, F1, F2, F3, F5） and notoginsenoside Fe（NFe） were studied. Among the saponins, the ginsenosides F1, F2, F3, F5 and NFe were determined by HPLC-UV method for the first time. The determination of the ginsenosides via the HPLC-UV method was performed on a reversed-phase C18 column with gradient elution in 40 min. The linearity, precision, accuracy, and detection limit for determining the saponins were studied and the samples from different areas in China were analyzed. The HPLC-ESI-MS was used to identify the saponins. The results indicate that the HPLC-UV provided a good accuracy, reproducibility and sensitivity for the determination of the ten saponins.

关键词： Panax ginseng C. A. Mey. Saponins HPLC Quantification Determination

Preparation and Inhibitory Effects of 20(S)-Ginsenoside Rh_2 on Hep-A-22 Cells

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Chemical Research in Chinese Universities 2010年第4期26卷 567-571页

作者： zhou hong-yu JIN Yong-ri WEI Wei SHI Xiao-lei YANG Rui-jie YANG Shi-jie LI Xu-wen College of Chemistry Jilin Uuniversity Changchun 130012 P. R. China Basic Medical School Jilin Uuniversity Changchun 130021 P. R. China

A modified method of preparing 20（S）-ginsenoside Rh2（G-Rh2） and the inhibitory effect of 20（S）-ginsenoside Rh2 on Hep-A-22 cells were investigated. The total saponins and strong alkali were dissolved in glycerol at the atmospheric pressure, and the degradation was performed at a high temperature. After G-Rh2 had been isolated and purified, MTT（methyl thiazolyl tetrazolium） assay was applied to evaluating the effect of 20（S）-ginsenoside Rh2 on the cells viability and morphological changes were observed. It was shown that 20（S）-ginsenoside Rh2 can reduce Hep-A-22 cells viability in dose-dependent manner and the cells took on cell shrinkage, membrane blebbing, chromosomal condensations, especially under the higher concentrations of it. In conclusion, 20（S）-ginsenoside Rh2 can be prepared effectively that not only decreases viability but also induces the apoptosis of Hep-A-22 cells.

关键词： 20(S)-Ginsenoside Rh2 Preparation Alkaline-degradation Hep-A-22 cell Inhibitory effect

Matrix Solid-phase Dispersion Extraction of Alkaloids from the Roots of Aconitum kusnezoffii Reichb

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Chemical Research in Chinese Universities 2011年第1期27卷 23-27页

作者： WEI Wei LI Xu-wen SHI Xiao-lei zhou hong-yu YANG Rui-jie ZHANG Han-qi JIN Yong-ri College of Chemistry Jilin University Changchun 130012 P. R. China

Matrix solid-phase dispersion（MSPD） was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots ofAconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid support material, type of the elution solvent and the volume of the elution solvent were tested. Mean recoveries ranged from 93.16% to 102.73%, with relative standard deviations from 0.27% to 4.17%. With the extraction efficiency and time expenditure taken into account, MSPD extraction should be a comparatively good method.

关键词： Matrix solid-phase dispersion Aconitine-type alkaloid Aconitum kusnezoffii Reichb. Extraction High-performance liquid chromatography 1005-9040(2011 )-01-023-05

Dynamin like protein 1 participated in the hemoglobin uptake pathway of Plasmodium falciparum

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Chinese Medical Journal 2009年第14期122卷 1686-1691页

作者： zhou hong-chang GAO yu-hui Zhong Xiang WANG Heng Department of Microbiology and Parasitology Institute of Basic Medical Sciences Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College 5# Dong Dan San Tiao Rm. 522 Beijing 100005 China

Background During the blood stage of malaria infection, parasites internalize in the host red blood cells and degrade massive amounts of hemoglobin for their development. Although the morphology of the parasite＇s hemoglobin uptake pathway has been clearly observed, little has been known about its molecular mechanisms. Methods The recombinant proteins from Plasmodium falciparum, dynamin like protein 1 （PfDYN1） and 2 （PfDYN2） GTPase domain, were expressed in E .coil and showed GTPase activity. By using a dynamin inhibitor, dynasore, we demonstrated the involvement of PfDYN1 in the hemoglobin uptake pathway. Results The GTPase activity of the two recombinant proteins was inhibited by dynasore in vitro. Treatment of parasite cultures with 80 μmol/L dynasore at the ring and early trophozoite stage resulted in substantial inhibition of parasite growth and in an obvious decline of hemoglobin quantum. Furthermore, reduced intracellular hemozoin accumulation and decreased uptake of the FITC-dextran were also observed, together with distinctive changes in the ultrastructure of parasites after the dynasore treatment. Conclusions Our results show that PfDYN1 plays an important role in the hemoglobin uptake pathway of P. falciparum and suggest its possibility of being a novel target for malaria chemotherapy.

关键词： Plasmodium falciparum hemoglobin uptake dynamin inhibitor

Penetration depth and concentration distribution for implanted heavy ions with low energies in plant seeds by SEM and EDS

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Nuclear Science and Techniques 2001年第1期12卷 26-31页

作者： WANG Xin-Fu zhou yun-Long zhou hong-yu LU Ting Wang Chao SU Ying ZHU Guang-Hua WEN Chen-Lin LI Yong-Liang (Key Laboratory for Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Norm Key Laboratory for Beam Technology and Material Modificationof Ministry of Education Institute of Low Energy Nuclear PhysicsBeijing Normal University Beijing Radiation Center Department of Biology Beijing Normal University Center for Analysis and Testing Beijing Normal University

The penetration depth and concentration distribution of implanted ions have been studied for low energy heavy ions implanted in the dry seeds of plant, such as peanut, mung beau, sunflower, wheat and radish seeds, etc. by SEM+EDS. The results .how that the maximum penetration depth is about 12μm for V+ with an energy 200 keV implanted in cotyledon of the peanut, 18pm, spin, 20μm for V2+ with 90 keV implanted in sunflower, wheat, radish seeds, respectively. The penetration depth of implanted Cu2+ with 80 keV is about 90μm in the remainder funicle derivative of the mung beau seeds. The experimental result of the maximum penetration depth of implanted V+ in the peanut seeds was compared with the calculated value of the TRIM95.

关键词：离子移植渗透深度浓度分布植物种子

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直接俘获截面中的核晕效应

高能物理与核物理 2005年第10期29卷 974-977页

作者：刘祖华周宏余中国原子能科学研究院北京102413 北京师范大学低能核物理研究所北京100875

恒星能量下俘获截面非常难于直接测量.因此,通常借助于非直接方法或从最低能量下的实验数据外推到天体物理感兴趣能区.首先证明了用渐近归一化常数方法得到的结果近似与模型无关.因此,转移反应的渐近归一化常数方法处理提供了一可靠的... 详细信息

恒星能量下俘获截面非常难于直接测量.因此,通常借助于非直接方法或从最低能量下的实验数据外推到天体物理感兴趣能区.首先证明了用渐近归一化常数方法得到的结果近似与模型无关.因此,转移反应的渐近归一化常数方法处理提供了一可靠的途径用以确定恒星能量下的俘获截面.鉴于此优点,用渐近归一化常数方法计算了10Be(n,γ)11Be反应的俘获截面.11Be是一个众所周知的具有两弱束缚态的晕核.作为一个典型的例子,演示了俘获到晕态的辐射俘获截面明显增大,证明了入射中子波函数与晕的伸展尾部有较大重叠是俘获截面异常增大的原因.

关键词：核晕 ANC方法直接俘获晕效应辐射俘获截面转移反应归一化低能量直接测量天体物理

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中国创业投资网络的动态演进实证

系统工程理论与实践 2014年第11期34卷 2748-2759页

作者：周育红宋光辉华南理工大学经济与贸易学院广州510641 华南理工大学工商管理学院广州510641

文章基于所有投资于中国境内初创企业的7151件创业投资(以下简称"创投")事件,构建出历年来中国创投网络图,从社会网络结构角度考察中国创投业的动态演进特点,并与硅谷创投网络进行比较,研究发现:一、中国创投网络规模在逐年增加,但是网... 详细信息

文章基于所有投资于中国境内初创企业的7151件创业投资(以下简称"创投")事件,构建出历年来中国创投网络图,从社会网络结构角度考察中国创投业的动态演进特点,并与硅谷创投网络进行比较,研究发现:一、中国创投网络规模在逐年增加,但是网络质量却有下滑的趋势;二、不同所有权性质的创投机构在网络中的位置有明显的区别;三、在合作的创投网络中,中资创投机构表现消极处于弱势地位,外资一贯积极占据网络核心,合资善于学习网络地位越来越强.通过进一步分析,得出忽视网络建设的中资创投的快速增加,影响了中国创业投资网络质量,所以加强对经验不足的中资创投的引导就成为关键.

关键词：创业投资社会网络中心度凝聚子群动态演进