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848篇 您的检索式:作者名="Xiaoli Li"
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1Orbit determination and time synchronization for a GEO/IGSO satellite navigation constellation with regional tracking network显示文摘Aiming at regional services,the space segment of COMPASS (Phase I) satellite navigation system is a constellation of Geostationary Earth Orbit (GEO),Inclined Geostationary Earth Orbit (IGSO) and Medium Earth Orbit (MEO) satellites.Precise orbit determination (POD) for the satellites is limited by the geographic distribution of regional tracking stations.Independent time synchronization (TS) system is developed to supplement the regional tracking network,and satellite clock errors and orbit data may be obtained by simultaneously processing both tracking data and TS data.Consequently,inconsistency between tracking system and TS system caused by remaining instrumental errors not calibrated may decrease navigation accuracy.On the other hand,POD for the mixed constellation of GEO/IGSO/MEO with the regional tracking network leads to parameter estimations that are highly correlated.Notorious example of correlation is found between GEO's orbital elements and its clock errors.We estimate orbital elements and clock errors for a 3GEO+2IGSO constellation in this study using a multi-satellite precise orbit determination (MPOD) strategy,with which clock error elimination algorithm is applied to separate orbital and clock estimates to improve numerical efficiency.Satellite Laser Ranging (SLR) data are used to evaluate User Ranging Error (URE),which is the orbital error projected on a receiver's line-of-sight direction.Two-way radio-wave time transfer measurements are used to evaluate clock errors.Experimenting with data from the regional tracking network,we conclude that the fitting of code data is better than 1 m in terms of Root-Mean-Square (RMS),and fitting of carrier phase is better than 1 cm.For orbital evaluation,difference between computed receiver-satellite ranging based on estimated orbits and SLR measurements is better than 1 m (RMS).For clock estimates evaluation,2-hour linear-fitting shows that the satellite clock rates are about 1.E-10 s/s,while receiver clock rates are about 1×10 13-1×10 12 s/s.For the 72-hour POD experiment,the average differences between POD satellite clock rates estimates and clock measurements based on TS system are about 1×10 13 s/s,and for receiver clock rates,the differences are about 1×10 15 s/s.ZHOU ShanShi HU XiaoGong WU Bin LIU Li QU WeiJing GUO Rui HE Feng CAO YueLing Wu XiaoLi ZHU LingFeng SHI Xin TAN HongLi 2011Science China(Physics,Mechanics & Astronomy)2011,54,6:44
2Anatomical and chemical characteristics associated with lodging resistance in wheat显示文摘Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diameter, and stem diameter, were extensively investigated in earlier studies. However, the solid stem trait was rarely considered. In this study, we measured a range of anatomical and chemical characteristics on solid and hollow stemmed wheat cultivars. Significant correlations were detected between resistance to lodging and several anatomical features, including width of mechanical tissue, weight of low internodes, and width of stem walls. Morphological features that gave the best indication of improved lodging resistance were increased stem width, width of mechanical tissue layer, and stem density. Multiple linear regression analysis showed that 99% of the variation in lodging resistance could be explained by the width of the mechanical tissue layer, suggesting that solid stemmed wheat has several anatomical features for increasing resistance to lodging. In addition, microsatellite markers GWM247 and GWM340 were linked to a single solid stem QTL on chromosome 3BL in a population derived from the cross Xinongshixin(solid stem)/Line 3159(hollow stem). These markers should be valuable in breeding wheat for solid stem.Eryan Kong Dongcheng Liu Xiaoli Guo Wenlong Yang Jiazhu Sun Xin Li Kehui Zhan Dangqun Cui Jinxing Lin Aimin Zhang 2013The Crop Journal2013,1,1:43
3Impact of land use change on water resource allocation in the middle reaches of the Heihe River Basin in northwestern China显示文摘In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid re- gions of northwestern China. In order to sustain the expanding cropland, people increased groundwater exploitation in these regions. The purpose of this study was to quantitatively analyze the changes in land use and water re- sources, and their relationship in the middle reaches of the Heihe River Basin, a typical inland river basin in northwest China. The data of land use change were interpreted using aerial photographs(1965) and Landsat TM images(1986 and 2007). The data of irrigation water volume in the irrigation districts were spatialized in the middle reaches of the Heihe River Basin. The spatial variation of the groundwater depth was interpolated using the geo- statistical method. The results showed that the cultivated cropland area along oasis fringe increased by 15.38% and 43.60% during the periods 1965–1986 and 1986–2007, respectively. Surface water amount for irrigation had almost doubled from 1956 to 2010. The decrease of grassland area mainly occurred at the alluvial fan in front of the Qilian Mountains, with 36.47% during 1965–1986 and 38.56% during 1986–2007, respectively. The groundwater depth in front of the mountain constantly increased from 1986 to 2007. We found that the overuse of surface water and overexploitation of groundwater had direct consequences on the natural environments. We suggests that the efficiency of surface water resources use among different irrigation districts needs to be improved, which will sig- nificantly ease the conflicts between increasing water demand for irrigation and a shortage of water resources in the middle reaches of the Heihe River Basin.YanYun NIAN Xin LI Jian ZHOU XiaoLi HU 2014Journal of Arid Land2014,6,3:32
4Structural changes of gut microbiota in Parkinson's disease and its correlation with clinical features显示文摘The aim of this study was to compare the structure of gut microbiota in Parkinson's disease(PD) patients and healthy controls;and to explore correlations between gut microbiota and PD clinical features. We analyzed fecal bacterial composition of 24 PD patients and 14 healthy volunteers by using 16 S rRNA sequencing. There were significant differences between PD and healthy controls, as well as among different PD stages. The putative cellulose degrading bacteria from the genera Blautia(P=0.018),Faecalibacterium(P=0.048) and Ruminococcus(P=0.019) were significantly decreased in PD compared to healthy controls.The putative pathobionts from the genera Escherichia-Shigella(P=0.038), Streptococcus(P=0.01), Proteus(P=0.022), and Enterococcus(P=0.006) were significantly increased in PD subjects. Correlation analysis indicated that disease severity and PD duration negatively correlated with the putative cellulose degraders, and positively correlated with the putative pathobionts. The results suggest that structural changes of gut microbiota in PD are characterized by the decreases of putative cellulose degraders and the increases of putative pathobionts, which may potentially reduce the production of short chain fatty acids, and produce more endotoxins and neurotoxins; and these changes is potentially associated with the development of PD pathology.Wei Li Xiaoli Wu Xu Hu Tao Wang Shan Liang Yunfeng Duan Feng Jin Bin Qin 2017Science China(Life Sciences)2017,60,11:26
5Effect of Lichong decoction on expression of Bcl-2 and Bcl-2-associated X protein mRNAs in hysteromyoma model rat显示文摘OBJECTIVE:To study on effects of Lichong decoction on expression of apoptosis-controlling genes,Bcl-2 and Bcl-2-associated X protein(Bax) mRNAs in hysteromyoma tissue of the hysteromyoma model rat.METHODS:Fifty Wistar female rats were randomly divided into a normal group,a model group,a Lichong decoction group,a Guizifuling capsule group and a Mifepristone group.The hysteromyoma rat model was established by intraperitoneal injection of exogenous estrin and progestogens.Pathological examination of uterine tissue,uterine coefficient and uterine transverse diameter were made under optic microscope and expressions of Bcl-2 and Bax mRNAs in uterine tissue in the groups were detected with real-time fluorescent quantitative polymerase chain reaction(PCR) technique.RESULTS:After treatment,under microscope it was found that in the Lichong decoction group myometrium thinned,muscle fiber slightly overgrowth or long and thin,regular arrangement,inserting phenomenon of inner circular muscle and external longitudinal muscle was occasionally or not seen in the Lichong decoction group.The uterine coefficient and the uterine transverse diameter significantly decreased(P<0.01),and Bcl-2 mRNA expression significantly decreased(P<0.01) and Bax mRNA expression significantly increased in hysteromyoma tissue(P<0.01) in the Lichong decoction group as compared with the model group.CONCLUSION:Therapeutic effects of Lichong decoction on hysteromyoma is related with decrease of Bcl-2 mRNA expression and increase of Bax mRNA expression.Donghua Li Xin Xu Ruiya Qian Jianguo Geng Yan Zhang Xiaolei Xie Yasong Wang Xiaoli Zou 2013Journal of Traditional Chinese Medicine2013,33,2:24
6Altered trends in carbon uptake in China’s terrestrial ecosystems under the enhanced summer monsoon and warming hiatus显示文摘The carbon budgets in terrestrial ecosystems in China are strongly coupled with climate changes.Over the past decade,China has experienced dramatic climate changes characterized by enhanced summer monsoon and decelerated warming.However,the changes in the trends of terrestrial net ecosystem production(NEP)in China under climate changes are not well documented.Here,we used three ecosystem models to simulate the spatiotemporal variations in China's NEP during 1982–2010 and quantify the contribution of the strengthened summer monsoon and warming hiatus to the NEP variations in four distinct climatic regions of the country.Our results revealed a decadal-scale shift in NEP from a downtrend of–5.95 Tg C/yr^2(reduced sink)during 1982–2000 to an uptrend of 14.22 Tg C/yr^2(enhanced sink)during 2000–10.This shift was essentially induced by the strengthened summer monsoon,which stimulated carbon uptake,and the warming hiatus,which lessened the decrease in the NEP trend.Compared to the contribution of 56.3%by the climate effect,atmospheric CO2 concentration and nitrogen deposition had relatively small contributions(8.6 and 11.3%,respectively)to the shift.In conclusion,within the context of the global-warming hiatus,the strengthening of the summer monsoon is a critical climate factor that enhances carbon uptake in China due to the asymmetric response of photosynthesis and respiration.Our study not only revealed the shift in ecosystem carbon sequestration in China in recent decades,but also provides some insight for understanding ecosystem carbon dynamics in other monsoonal areas.Honglin He Shaoqiang Wang Li Zhang Junbang Wang Xiaoli Ren Lei Zhou Shilong Piao Hao Yan Weimin Ju Fengxue Gu Shiyong Yu Yuanhe Yang Miaomiao Wang Zhongen Niu Rcmg Ge Huimin Yan Mei Huang Guoyi Zhou Yongfei Bai Zongqiang Xie Zhiyao Tang Bingfang Wu Leiming Zhang Nianpeng He Qiufeng Wang Guirui Yu 2019National Science Review2019,6,3:24
7Inferring three-dimensional surface displacement field by combining SAR interferometric phase and amplitude information of ascending and descending orbits显示文摘Conventional Interferometric Synthetic Aperture Radar(InSAR) technology can only measure one-dimensional surface displacement(along the radar line-of-sight(LOS) direction).Here we presents a method to infer three-dimensional surface displacement field by combining SAR interferometric phase and amplitude information of ascending and descending orbits.The method is realized in three steps:(1) measuring surface displacements along the LOS directions of both ascending and descending orbits based on interferometric phases;(2) measuring surface displacements along the azimuth directions of both the ascending and descending orbits based on the SAR amplitude data;and(3) estimating the three-dimensional(3D) surface displacement field by combining the above four independent one-dimensional displacements using the method of least squares and Helmert variance component estimation.We apply the method to infer the 3D surface displacement field caused by the 2003 Bam,Iran,earthquake.The results reveal that in the northern part of Bam the ground surface experienced both subsidence and southwestward horizontal movement,while in the southern part uplift and southeastward horizontal movement occurred.The displacement field thus determined matches the location of the fault very well with the maximal displacements reaching 22,40,and 30 cm,respectively in the up,northing and easting directions.Finally,we compare the 3D displacement field with that simulated from the Okada model.The results demonstrate that the method presented here can be used to generate reliable and highly accurate 3D surface displacement fields.HU Jun LI ZhiWei ZHU JianJun REN XiaoChong DING XiaoLi 2010Science China Earth Sciences2010,53,4:21
8Radix Astragali-induced differentiation of rat bone marrow-derived mesenchymal stem cells显示文摘BACKGROUND:Chemical induction has been shown to be effective at promoting the differentiation of bone marrow-derived mesenchymal stem cells(MSCs).However,these inductors have cytotoxicity side effects that may damage cells over time.Traditional Chinese medicines avoid this disadvantage while still producing effective induction. OBJECTIVE:To investigate the influence of Radix Astragali(Huangqi) on the differentiation of MSCs. DESIGN,TIME AND SETTING:In vitro study of traditional Chinese medicine in neural stem cell differentiation.The experiment was performed at the Central Laboratory of Hebei North University between April and June 2007. MATERIALS:Radix Astragali solution(lot No.060105;license No.Z53021585) was purchased from Dali Pharmaceutical Co.,Ltd.,China;rabbit anti-rat nestin,rabbit anti-rat neuron-specific enolase (NSE),mouse anti-rat microtubule-associated protein 2,and rabbit anti-rat glial fibrillary acidic protein were purchased from Wuhan Boster,China. METHODS:Whole bone marrow was isolated from the femur and tibia of 6-week-old male Wistar rats and subcultured.The fourth passage of MSCs were harvested and induced by different concentrations(50,100,200,400 g/L) of Radix Astragali. MAIN OUTCOME MEASURES:Hematoxylin-eosin staining was used to observe MSC morphology after 24 hours of induction.Immunocytochemistry was employed to observe the expression of NSE (specific neuronal marker),nestin(marker of neural stem cell),glial fibrillary acidic protein and microtubule-associated protein 2(markers of astrocytes). RESULTS:Following Radix Astragalitreatment,changes occurred in cell morphology including:cell body pyknosis;thin and long processes formed in some cells,with growth corresponding to drug concentration and induction time;and the formation of network-like connections between some cells. With increasing drug concentration and induction time,nestin expression was upregulated,and the number of positive cells increased;cells produced NSE,glial fibrillary acidic protein and microtubule-associated protein 2;nestin was expressed earlier than glial fibrillary acidic protein and microtubule-associated protein 2 expression.In addition,the number of NSE-positive cells was increased significantly more than glial fibrillary acidic protein-positive cells. CONCLUSION:Radix Astragali promoted process formation in stem cells.It may induce the differentiation of MSCs into neural stem cells,and subsequently into neuronal-and glial-like cells. Radix Astragali exhibits stronger inductive effect on neuronal differentiation than glial differentiation of MSCs.Xinsheng Wang Haifeng Li Ying Zhao Xiaoli Zhang Aihua Bo 2009Neural Regeneration Research2009,4,7:21
9Temporal variations and source apportionment of volatile organic compounds at an urban site in Shijiazhuang, China显示文摘Shijiazhuang,the city with the worst air quality in China,is suffering from severe ozone pollution in summer.As the key precursors of ozone generation,it is necessary to control the Volatile Organic Compounds(VOCs)pollution.To have a better understanding of the pollution status and source contribution,the concentrations of 117 ambient VOCs were analyzed from April to August 2018 in an urban site in Shijiazhuang.Results showed that the monthly average concentration of total VOCs was 66.27 ppbv,in which,the oxygenated VOCs(37.89%),alkanes(33.89%),and halogenated hydrocarbons(13.31%)were the main composite on.Eight major sources were identified using Positive Matrix Factorization modeling with an accurate VOCs emission inventory as inter-complementary methods revealed that the petrochemical industry(26.24%),other industrial sources(15.19%),and traffic source(12.24%)were the major sources for ambient VOCs in Shijiazhuang.The spatial distributions of major industrial activities emissions were identified by using geographic information statistics system,which illustrated the VOCs was mainly from the north and southeast of Shijiazhuang.The inverse trajectory analysis using Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)and Potential Source Contribution Function(PSCF)clearly demonstrated the features of pollutant transport to Shijiazhuang.These findings can provide references for local governments regarding control strategies to reduce VOCs emissions.Yanan Guan Lei Wang Shujuan Wang Yihao Zhang Jieying Xiao Xiaoli Wang Erhong Duan Li'an Hou 2020Journal of Environmental Sciences2020,32,11:19
10Water quality criteria research and progress显示文摘Water quality criteria (WQC) are threshold limits for pollutants or other hazard factors in the ambient water environment, which are based on scientific experiments and extrapolations. Until now, there is limited information available regarding the study of water quality criteria in China. It is imperative to launch national-level systematic WQC studies that focus on the regional characteristics of China and provide scientific support for the enactment or revision of water quality standards and environmental management. This article reviews the concept of WQC and discusses the methodology and global progress of WQC research. The article also summarizes the key scientific issues in WQC research, including species sensitivity distribution, toxicological endpoint selection, and models selection. Furthermore, we can adopt the derivation method used in the USA and divide WQC into acute and chronic criteria. Finally, considering the current status of WQC research in China, we point out important directions for future national studies, including the selection of native species and the comprehensive use of models.FENG ChengLian WU FengChang ZHAO XiaoLi LI HuiXian CHANG Hong 2012Science China Earth Sciences2012,55,6:18
11Identification of rice cultivars with low brown rice mixed cadmium and lead contents and their interactions with the micronutrients iron,zinc,nickel and manganese显示文摘Paddy fields in mining areas are usually co-contaminated by a cocktail of mixed toxic heavy metals(e.g.,Cd and Pb in Pb/Zn mines).However,previous studies on rice cultivars screened for effective metal exclusion have mostly focused on individual metals,and have been conducted under pot-trial or hydroponic solution conditions.This study identified rice cultivars with both low Cd and Pb accumulation under Cd-and Pb-contaminated field conditions,and the interactions of the toxic elements Cd and Pb with the micronutrient elements Fe,Zn,Mn and Ni were also studied.Among 32 rice cultivars tested,there were significant differences in Cd(0.06-0.59 mg/kg) and Pb(0.25-3.15 mg/kg) levels in their brown rice,and similar results were also found for the micronutrient elements.Significant decreases in concentrations of Fe and Mn were detected with increasing Cd concentrations and a significant elevation in Fe,Mn and Ni with increasing Pb concentrations.A similar result was also shown by Cd and Ni.Three cultivars were identified with a combination of low brown rice Cd and Pb,high micronutrient and grain yield(Wufengyou 2168,Tianyou 196 and Guinongzhan).Present results suggest that it is possible to breed rice cultivars with low mixed toxic element(Cd,Pb) and high micronutrient contents along with high grain yields,thus ensuring food safety and quality.Bing Li Xun Wang Xiaoli Qi Lu Huang Zhihong Ye 2012Journal of Environmental Sciences2012,24,10:18
12Ground settlement of Chek Lap Kok Airport,Hong Kong,detected by satellite synthetic aperture radar interferometry显示文摘Satellite synthetic aperture radar (SAR) inter-ferometry is used to investigate the slowly accumulating ground settlement at the new Chek Lap Kok Airport in Hong Kong. Most of the land occupied by the airport was reclaimed from the sea and therefore certain ground settlement in the area has been expected. A pair of ERS-2 SAR images spanning nearly a year is used in the study. The high spatial resolution (20 m×20 m) ground settlement map derived indicates that the settlement that occurred in the area over the time period is as large as 50 mm. The SAR measurement results agree with the levelling measurements at some benchmarks in the area to well within 1 cm(rms error),and the overall correlation between the two types of results is 0.89. The paper presents some brief background of inter-ferometric SAR, and outlines the data processing methods and results.LIU Guoxiang DING Xiaoli CHEN Yongqi LI Zhilin LI Zhiwei 2001Chinese Science Bulletin2001,46,21:16
13Contrasting Effects of Ethylene Biosynthesis on Induced Plant Resistance against a Chewing and a Piercing-Sucking Herbivore in Rice显示文摘乙烯是有在草食动物抵抗上对比效果的压力荷尔蒙。然而,这些差别是否植物特定或草食动物特定,仍然保持未知。我们克隆米饭 1-aminocyclopropane-1-carboxylic 酸(ACC ) synthase 基因, OsACS2,其抄本响应由二个重要害虫的机械伤害和群袭是很快起来调整的:有斑纹的茎 borer (SSB ) Chilo suppressalis 和棕色的 planthopper (BPH ) Nilaparvata lugens。OsACS2 (当交流) 的 Antisense 表示减少了得到的乙烯排放,得到 SSB 的胰岛素朊酶禁止者(TrypPI ) 活动,导致 SSB 的不稳定的版本,和 SSB 抵抗。ACC 的外长的申请恢复了 TrypPI 活动和 SSB 抵抗。与 SSB 相对照, BPH 群袭在当交流线增加了不稳定的排放。因此, BPH 喜欢喂并且在上产卵野类型(WT ) 能被归因于二讨厌的 volatiles, 2-heptanone 和 2-heptanol 的 plantsan 效果,那被当交流植物在更高的数量射出。BPH 蜜露排泄被减少,生来的敌人吸引力在当交流线被提高,导致到 BPH 的更高全面的抵抗。这些结果证明发信号的乙烯对咀嚼和一只穿透吸昆虫在米饭防卫回答和电阻上有形成对照的、草食动物特定的效果,并且可以调停在不同的喂的草食动物之间的抵抗交易在米饭的行业协会。Jing Lu Jiancai Li Hongping Ju Xiaoli Liu Matthias Erb Xia Wang Yonggen Lou 2014Molecular Plant2014,7,11:15
14Numerical simulation and experimental investigation of natural convection heat transfer of molten salt around fine wire显示文摘In order to get the natural convection heat transfer mechanism of molten salt, the experimental investigation of natural convective heat transfer of LiNO3was studied after it was simulated by numerical calculation. Experiment was carried out on the nat-ural convection heat transfer of air and water around the fine wire using the method of Joule heating. The results showed that the natural convection heat transfer of air and water around the fine wire agreed well with Fand's correlation. Based on the aforementioned experiment, the natural convection heat transfer of molten salt LiNO3was studied by experiment and the same results were got. Therefore, the natural convection heat transfer of molten salt can be calculated by Fand's correlation, which takes into consideration the effect of viscosity dissipation.LU YuanWei LI XiaoLi LI Qiang WU YuTing MA ChongFang 2013Science China(Technological Sciences)2013,56,7:13
15Value of magnetic resonance imaging including dynamic contrast-enhanced magnetic resonance imaging in differentiation between inverted papilloma and malignant tumors in the nasal cavity显示文摘Wang Xinyan Zhang Zhengyu Chen Xiaoli Li Jing Xian Junfang 2014Chinese Medical Journal2014,,9:13
16S phase-dependent interaction with DNMT1 dictates the role of UHRF1 but not UHRF2 in DNA methylation maintenance显示文摘最近的研究证明 UHRF1 被指向 DNMT1 到 DNA 复制 foci 为 DNA methylation 维护要求,大概通过它的唯一的半甲醇化物有 DNMT1 的 DNA 有约束力的活动和相互作用。UHRF2, UHRF 家庭蛋白质的另一个成员,高度类似于在顺序和结构的 UHRF1,关于它在 DNA methylation 的角色的涨的问题。在这研究,我们证明 UHRF2 象 UHRF1 一样,也优先地绑在 methylated histone H3 离氨酸 9 (H3K9 ) 通过它的保存 tudor,通过 SET 和戒指的领域和半甲醇化物 DNA 联系了领域。象 UHRF1 一样, UHRF2 在 pericentric heterochromatin 被充实。heterochromatin 本地化取决于到大程度它的 methylated H3K9 有约束力的活动并且到它的 methylated 上的更少的程度 DNA 有约束力的活动。Coimmunoprecipitation 实验证明 UHRF1 和 UHRF2 与 DNMT1, DNMT3a, DNMT3b 和 G9a 交往。尽管有所有这些保存功能,我们发现 UHRF2 不能在 Uhrf1 空老鼠救 DNA methylation 缺点胚胎的干细胞。这个罐头在房间周期的 S 阶段期间为 UHRF2 被归因于无能到成员 DNMT1 到复制 foci。确实,我们发现当 UHRF1 在房间以一种 S 阶段依赖者方式与 DNMT1 交往时, UHRF2 不做。因此,我们的学习证明 UHRF2 和 UHRF1 不在 DNA methylation 维护是机能上地冗余的并且作为为 DNA methylation 指向 DNMT1 的关键规章的机制揭示在 UHRF1 和 DNMT1 之间的 cell-cycle-dependent 相互作用。Jiqin Zhang Qinqin Gao Pishun Li Xiaoli Liu Yuanhui Jia Weicheng Wu Jiwen Li Shuo Dong Haruhiko Koseki Jiemin Wong 2011Cell Research2011,21,12:12
17Lichong decoction reduces Matrix Metalloproteinases-2 expression but increases Tissue Inhibitors of Matrix Metalloproteinases-2 ex-pression in a rat model of uterine leiomyoma显示文摘OBJECTIVE:To study the effect of Lichong decoction(LD) on expression of matrix metalloproteinase-2(MMP-2) and metalloproteinase-2(TIMP-2) in a rat model of uterine leiomyoma(UL).METHODS:UL was induced in rats using exogenous estrogen and progesterone.LD was administered(p.o.) for 4 weeks,and mifepristone(RU-486)used as a control.To observe the effect of LD on the uterine coefficient and uterine transverse diameter,a radioimmunoassay method was used to detect serum levels of sex hormones.Light microscopic analyses of pathologic changes in the tissues of UL rats were evaluated.Expression of the proteins of matrix metalloproteinases(MMPs) and tissue inhibitors of metalloproteinases(TIMPs) in uterine tissues was assessed by immunohistochemical staining and western blotting.RESULTS:A UL model in rats was established successfully.LD reduced uterine weight,uterine coefficient,and uterine transverse diameter compared with untreated controls.LD reduced levels of estradiol,progesterone,follicle-stimulating hormone,and luteinizing hormone in our UL models.LD improved the pathologic condition of uterine muscle.Expression of MMP-2 protein decreased to varying extents in LD-treated groups,but TIMP-2 levels were enhanced.LD appears to reduce MMP-2 expression and increase TIMP-2 expression in UL tissue.CONCLUSION:These data suggest that the mechanism of action of LD on ULs may involve reduction of MMP-2 expression and increase in TIMP-2 expression in rats.Wang Yasong Li Donghua Xu Xin Qian Ruiya Zhang Yalan Huang Yuhua Geng Jianguo Zou Xiaoli Han Hon-gjuan Zhang Wufang 2016Journal of Traditional Chinese Medicine2016,36,4:12
18Effects of Saikosaponin-D on syndecan-2,matrix metalloproteinases and tissue inhibitor of metalloproteinases-2 in rats with hepatocellular carcinoma显示文摘OBJECTIVE:To investigate effects of Saikosaponin D(SSd) on syndecan-2,matrix metalloproteinases(MMPs) and tissue inhibitor of metalloproteinases-2(TIMP-2) in livers of rat with hepatocellular carcinoma(HCC).METHODS:Male SD rats were divided into control(n=10),model(n=20) and SSd(n=20) groups,and model and SSd groups given intragastric 0.2%(w/v) N-diethylnitrosamine to induce HCC.SSd group received 0.03%(w/v) SSd in saline.Liver samples were analysed immunohistochemically for syndecan-2,MMP-2,MMP-13 and TIMP-2 at 16 weeks.RESULTS:The model group had more malignant nodules than the SSd group;all model-group HCC cells were grade III;SSd-group HCC cells were grades I-II.Controls showed normal hepatic cell phenotypes and no syndecan-2 + staining.Syndecan-2 + staining was greater in the model group(35.2%,P≤0.001) than in controls or the SSd group(16.5%,P ≤ 0.001).The model group had more intense MMP-2 + staining than controls(0.37 vs 0.27,P≤0.01) or the SSd group(0.31 vs 0.37,P≤0.05);and higher MMP-13 + staining(72.55%) than in controls(12.55%,P≤0.001) and SSd group(20.18%,P≤0.01).The model group also had more TIMP-2 + staining(57.2%) than controls(20.9%,P≤0.001) and SSd group(22.7%,P≤0.001).Controls and SSd group showed no difference in TIMP-2 + rates.CONCLUSION:SSd inhibited HCC development,and downregulated expression of syndecan-2,MMP-2,MMP-13 and TIMP-2 in rat HCC liver tissue.Xiaoli Jia Shuangsuo Dang Yanan Cheng Xin Zhang Mei Li Yaping Li Siyuan Li 2012Journal of Traditional Chinese Medicine2012,32,3:12
19Urban expansion in China and its effect on cultivated land before and after initiating'Reform and Open Policy'显示文摘Urbanization in China has expanded at an unprecedented speed since the declaration of 'Reform and Open Policy'and presented many challenges. Unbalanced regional development, appearance of super megacities and concomitant problems,and conflicts between urbanization and cultivated land protection are three critical problems that Chinese urbanization has to face. To develop new plans for foreseeable future urbanization in China, it is critical to understand the evolving history of cities across China. This study maps urban expansion of 60 typical Chinese cities based on large amount of remote sensing data and the labor-intensive image interpretation method, in order to understand the history of urban expansion from the 1970 s to 2013.Results showed that area of cities expanded 5.23 times compared to their area in the 1970 s. Urban expansion in China accelerated three times(1988–1996, 1999–2006, and 2009–2011) and decelerated three times(1997–1998, 2007–2008, and 2012–2013) over the 40 years. The urban area of South China expanded most significantly 9.42 times, while the urban area in Northeast China expanded only 2.37 times. The disparity among different administrative ranks of cities was even greater than(3.81 times) the differences among different regions. Super megacities have been continuously expanding at a fast rate(8.60-fold), and have not shown obvious signs of slowing down. The proportion of cultivated land among the land sources for urban expansion decreased to a small extent in the 1990 s, but cultivated land continues to be the major land source for urban expansion. Effective future urbanization needs controlling the expansion scale of large cities and reasonably developing medium and small cities, as well as balancing regional development.ZHANG ZengXiang WEN QingKe LIU Fang ZHAO XiaoLi LIU Bin XU JinYong YI Ling HU ShunGuang WANG Xiao ZUO LiJun LI Na LI MinMin SHI LiFeng ZENG Tian JU HongRun 2016Science China Earth Sciences2016,59,10:12
20The enhanced X-ray Timing and Polarimetry mission—eXTP显示文摘In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources.The paper provides a detailed description of:(1) the technological and technical aspects, and the expected performance of the instruments of the scientific payload;(2) the elements and functions of the mission, from the spacecraft to the ground segment.ShuangNan Zhang Andrea Santangelo Marco Feroci YuPeng Xu FangJun Lu Yong Chen Hua Feng Shu Zhang Sφren Brandt Margarita Hernanz Luca Baldini Enrico Bozzo Riccardo Campana Alessandra De Rosa YongWei Dong Yuri Evangelista Vladimir Karas Norbert Meidinger Aline Meuris Kirpal Nandra Teng Pan Giovanni Pareschi Piotr Orleanski QiuShi Huang Stephane Schanne Giorgia Sironi Daniele Spiga Jiri Svoboda Gianpiero Tagliaferri Christoph Tenzer Andrea Vacchi Silvia Zane Dave Walton ZhanShan Wang Berend Winter Xin Wu Jean J.M.in't Zand Mahdi Ahangarianabhari Giovanni Ambrosi Filippo Ambrosino Marco Barbera Stefano Basso Jörg Bayer Ronaldo Bellazzini Pierluigi Bellutti Bruna Bertucci Giuseppe Bertuccio Giacomo Borghi XueLei Cao Franck Cadoux Francesco Ceraudo TianXiang Chen Yu Peng Chen Jerome Chevenez Marta Civitani Wei Cui WeiWei Cui Thomas Dauser Ettore Del Monte Sergio Di Cosimo Sebastian Diebold Victor Doroshenko Michal Dovciak YuanYuan Du Lorenzo Ducci QingMei Fan Yannick Favre Fabio Fuschino JoséLuis Ga'lvez Min Gao MingYu Ge Olivier Gevin Marco Grassi QuanYing Gu YuDong Gu DaWei Han Bin Hong Wei Hu Long Ji ShuMei Jia WeiChun Jiang Thomas Kennedy Ingo Kreykenbohm Irfan Kuvvetli Claudio Labanti Luca Latronico Gang Li MaoShun Li Xian Li Wei Li ZhengWei Li Olivier Limousin HongWei Liu XiaoJing Liu Bo Lu Tao Luo Daniele Macera Piero Malcovati Adrian Martindale Malgorzata Michalska Bin Meng Massimo Minuti Alfredo Morbidini Fabio Muleri Stephane Paltani Emanuele Perinati Antonino Picciotto Claudio Piemonte JinLu Qu Alexandre Rachevski Irina Rashevskaya Jerome Rodriguez Thomas Schanz ZhengXiang Shen LiZhi Sheng JiangBo Song LiMing Song Carmelo Sgro Liang Sun Ying Tan Phil Uttley Bo Wang DianLong Wang GuoFeng Wang Juan Wang LangPing Wang YuSa Wang Anna L.Watts XiangYang Wen Jörn Wilms ShaoLin Xiong JiaWei Yang Sheng Yang YanJi Yang Nian Yu WenDa Zhang Gianluigi Zampa Nicola Zampa Andrzej A.Zdziarski AiMei Zhang ChengMo Zhang Fan Zhang Long Zhang Tong Zhang Yi Zhang XiaoLi Zhang ZiLiang Zhang BaoSheng Zhao ShiJie Zheng Yu Peng Zhou Nicola Zorzi J.Frans Zwart 2019Science China(Physics,Mechanics & Astronomy)2019,62,2:11
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