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Norditerpenoid Alkaloids from Aconitum spicatum Stapf

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Journal of Integrative Plant Biology 2006年第3期48卷 364-369页

作者： Li-Ming Gao Hai-Yan Yan Yang-Qing He xiao-mei wei Department of Chemistry Key Laboratory of Polymer Materials of Gansu Province Northwest Normal University Lanzhou 730070 China

To search for pharmacologically and structurally interesting substances from traditional Chinese medicines, we Investigated the chemical compounds of Aconitum spicatum Stapf. Two new nordlterpenold alkaloids, namely spicatlne A （compound 1） and splcatine B （compound 2）, as well as 11 known norditerpenoid alkaloids were Isolated from the CHCIs portion of the 90% ethanol extract of the roots of A. spicatum. The structures of the alkaloids were characterized on the basis of their spectral data. One of the Isolated compounds showed significant cytotoxic activities （IC50 values 〈 200μmol/l.） against the HL-60 cell line.

关键词： Aconitum spicatum cytotoxic activity norditerpenoid alkaloids spicatine A spicatine B.

Two new diterpene alkaloids from Delphinium chrysotrichum

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Chinese Chemical Letters 2007年第5期18卷 545-547页

作者： Yang Qing He xiao mei wei Yi Li Han Li Ming Gao Department of Applied Chemistry Xi＇ an University of Technology Xi＇ an 710054 China Department of Chemistry Key Laboratory of Polymer Materials of Gansu Province Northwest Normal University Lanzhou 730070 China

Chemical investigation on the ethanol extract from the whole plants of Delphinium chrysotrichum resulted in the isolation of two new diterpene alkaloids named delphatisine A （1） and delphatisine B （2）, respectively. The structures of the new compounds were deduced on the basis of their spectral data （IR, HREIMS, EIMS, 1 D, 2D-NMR）. This is the first report on the isolation of diterpenoid alkaloids from the D. chrysotrichum.

关键词： Delphinium chrysotrichum Diterpene alkaloids Delphatisine A Delphatisine B

Two New Iridoid Glucosides from Clerodendrum serratum

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Chinese Chemical Letters 2000年第5期11卷 415-416页

作者： xiao mei wei Qi Xiou ZHU Jin Chun CHEN Dong Liang CHENG (Department of Chemistry, National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000) Department of Chemistry Natl. Lab. of Appl. Organ. Chemistry Lanzhou University Lanzhou 730000 China

Two new iridoid glucosides, named 7 beta -coumaroyloxyugandoside (1) and 7 beta - cinnamoyloxyugandoside (2) were isolated from the leaves of Clerodendrum serratum, and their structures were elucidated by spectral means.

关键词： Clerodendrum serratum Verbenaceae iridoid glucoside 7 beta-coumaroyloxyugandoside (1). 7 beta-cinnamoyloxyugandoside (2).

Localization and Functional Analysis of SeMNPV IE1 in Mammalian Cells

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Virologica Sinica 2010年第3期25卷 183-190页

作者： xiao-wei mei Li YAO Zhong-xin ZHANG State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China Graduate school Chinese Academy of Sciences Beijing 100039 China

In this paper, the function of the iel gene from baculovirus Spodoptera exigua multiple nucleopolyhedrovirus （SeMNPV）, belonging to group II nucleopolyhedrovirus, was studied in mammalian cells We amplified the SeMNPV iel gene and expressed it by fusing to the C terminal of enhanced GFP protein in HEK 293 cells. Confocal microscopy revealed that the IE1-GFP fusion protein was localized in the nucleus of the mammalian cells. The promoter sequences of AcMNPV gp64, SeMNPV F protein and Drosophila hsp70 were also analyzed, to further study the function of SeMNPV IE1. The results showed that, in the absence of the hr sequence, IE1 improved the expression of the F promoter but didn＇t influence the gp64 promoter significantly, but IE1 moderately stimulated the hsp70 promoter.

关键词： Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) ie1 gene Function Mammalian cells

Outcome of in vitro fertilization in endometriosis-associated infertility： a 5-year database cohort study

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Chinese Medical Journal 2012年第15期125卷 2688-2693页

作者： LIN xiao-na wei Min-ling TONG xiao-mei XU wei-hai ZHOU Feng HUANG Qiong-xiao WEN Guo-feng ZHANG Song-ying Assisted Reproduction Unit Department of Obstetrics andGynecology Sir Run Run Shaw Hospital Zhejiang UniversitySchool of Medicine Hangzhou Zhejiang 310016 China

Background Endometriosis affects natural fertility through various approaches, and in vitro fertilization （IVF） is a good treatment. But the IVF result of endometriosis patients is still under debate. We investigated the effect of endometriosis on IVF by analyzing the data from a single reproductive center. Methods A retrospective, database-searched cohort study was performed. Relevant information was collected from the electronic records of women who underwent IVF/intracytoplasmic sperm injection between January 2006 and December 2010 in the Assisted Reproductive Unit of Sir Run Run Shaw Hospital. Patients with endometriosis were enrolled the study group. The rest of the women formed the control group. The main outcome was the clinical pregnancy rate. Secondary outcomes were oocytes retrieved number, fertilization rate, high-quality embryo rate, number of high-quality embryo for embryo transplantation, and implantation embryo/high-quality embryo ratio （IE/HQE ratio）. Comparisons were performed by the z2-test and independent t-test. Results The endometriosis group （n=177） had a markedly lower oocytes retrieved number, fertilization rate, implantation rate, and clinical pregnancy rate （7.6_＋5.1, 63.6%, 27.7%, and 45.2%, respectively） compared with the non-endometriosis group （n=4267; 11.8＋7.3, 68.4%, 36.2%, and 55.2%, respectively）. Stratified analysis showed that this difference was found in the subgroup younger than 35-years old, while only fertilization rate and implantation rate were different in the elder subgroup. The ratio of high-quality embryos transferred is lower in endometriosis group （53.7% vs. 71.8%, P 〈0.05）, but there is no difference in IE/HQE ratio between two groups. There is no significant difference in fertilization rate, implantation rate, and clinical pregnancy rate between mild and severe endometriosis patients. Conclusions Endometriosis patients suffer a decreasing IVF pregnancy rates mainly caused by reducing oocytes number and fertilization

关键词： fertilization in vitro, endometriosis pregnancy rate cohort study

QoS Guaranteed and Adaptive Downstream Bandwidth Utilization Scheme for Ethernet Passive Optical Networks

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Journal of Electronic Science and Technology 2011年第2期9卷 145-154页

作者： Chen Liu xiao-mei Fu Hong-wei Zhang School of Electronic Information Engineering Tianjin UniversityTianjin 300072China

Dynamic bandwidth allocation（DBA） is an open and hot topic in the Ethernet passive optical network（EPON） ,which is regarded as one of the best choices for next-generation access networks. However,most proposed DBA schemes ignore the quality of service（QoS） guarantee on maximum delay and delay jitter for the real-time traffic and the downstream bandwidth utilization under light upstream load in EPON. In this paper,a new DBA scheme,QoS guaranteed adaptive downstream bandwidth utilization（QoS-ADBU）,is proposed. This scheme can provide better QoS assurance by determining the maximum transmission cycle time according to the maximum acceptable packet delay and delay jitter for real-time traffic. Besides,the downstream utilization can also be improved by adapting the polling frequency to downstream traffic load.

关键词： Downstream bandwidth utilization dynamic bandwidth allocation Ethernet passive optical network quality of service guarantee

Oleanane-triterpene Saponins from Clinopodium urticifolium

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Chinese Chemical Letters 2003年第10期14卷 1041-1044页

作者： Li Ming GAO, xiao mei wei, Dong Liang CHENGDepartment of Chemistry, National Laboratory of Applied Organic Chemistry,Lanzhou University, Lanzhou 730000 Department of Chemistry, Northwest Normal University, Lanzhou 730070 Department of Chemistry National Laboratory of Applied Organic Chemistry Department of Chemistry Northwest Normal University

Four new oleanane triterpene saponins were isolated and purified from the whole plant of Clinopodium urticifolium. They were 3B 16B, 23, 28-tetrahydroxyoleana-9 (11), 12(13)-diene-3-yl-[B-D-glucopyranosyl-(1-2)]-[B-D-glucopyranosyl-(1-3)]- B-D-fucopyranoside 1; 3B, 16B, 21B, 23, 28-pentahydroxyoleana-9(11), 12(13)-diene-3-yl-[B-D-glucopyranosyl-(1-2)]-[B-D-glucopyranosyl-(1-3)]- B-D-fucopyranoside 2; 3B, 16B, 23, 28-tetrahydroxyoleana-9(11), 12(13)-diene-3-yl-[B-D-glucopyranosyl-(1-6)-B-D-glucopyranosyl-(1-3)]-[B-D-glucopyranosyl-(1-2)]-B-D-fucopyranoside 3; 3B, 16B, 23, 28-tetrahydroxyoleana-9(11), 12(13)-diene-3-yl-[B-D-gluco-pyranosyl-(1-4)-B-D-glucopyranosyl-(1-6)-B-D-glucopyranosyl-(1-3)]-[B-D-glucopyranosyl-(1-2)]- B-D-fucopyranoside 4. Their structures were elucidated on the basis of interpretation of NMR and MS data and from chemical evidence.

关键词： Clinopodium urticifolium Labiatae oleanane triterpene saponins.

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu xiao wei xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

<i>In Situ</i>Conservation of Wild Rice Populations: A Targeted Study of Common Wild Rice <i>Oryza rufipogon</i>from China

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American Journal of Plant Sciences 2012年第7期3卷 854-868页

作者： Li-Zhi Gao Dao-Yuan Li Xian-Qiang Wu Wen Chen Zhen-Man Huang xiao-mei wei Guangxi Agricultural School Nanning 530007 China Institute of Crop Germplasm Resources Guangxi Academy of Agricultural Sciences Nanning 530007 China Liaozhou Prefecture Institute of Agricultural Sciences Liaozhou 545000 China. Plant Germplasm and Genomics Center Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sci-ences Kunming China Rice Research Institute Hainan Academy of Agriculture Sciences Haikou 570000 China

Although great accomplishments of in situ conservation have been made during the last decade throughout the world, there is an urgent need to conduct more targeted research to explore many basic questions about crop wild relatives (CWR) in situ conservation such as how to better identify and manage the target in situ conservation populations of CWR. In this study, we performed an extensive field investigation of 201 natural populations or habitats of O. rufipogon, a seriously endangered wild progenitor of cultivated rice in China. Our updated information suggests that: 1) the majority of the natural populations have been extinct throughout China, which leads to serious fragmentation of the population system as a whole;and 2) the survived populations have become small in size and thus fragmented within the population as a result of the loss of subpopulations. To assess the relationships between the biodiversity education and conservation of wild rice, we employed participatory approaches in the field investigation. Our data indicate that the continuous rapid decline of biodiversity education seemed closely related to the extinction of wild rice germplasm. These findings imply the potential necessity and huge challenge for making in situ conservation plans in the future. By means of our understanding of ecogeography, sociology and culture, and population genetics of the species, we propose a strategy for selecting in situ conservation locations as well as priority sites for establishing in situ conservation practices in China.

关键词： In Situ Conservation Wild Rice Oryza rufipogon China