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Land Use Changes of an Aeolian-Loessial Soil Area in Northwest China: Implications for Ecological Restoration

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Pedosphere 2009年第3期19卷 356-361页

作者： CHEN Yu-Fu LIU Yan-Sui WANG Jing YAN Jian-Ping guo xu-dong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China） Key Laboratory of Land Use Institute of Land Surveying ~ Planning Ministry of Land ＆ Resources Beijing 100035（China）

China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigated to illustrate land use changes and their implications for environmental and long-term rural economic development. The farmland in Hengshan County significantly decreased during 1990–2003, whereas forest land and grassland increased. The conversion rates of farmland, orchard land, forest land and construction land varied markedly among different periods: 1990–1995, 1995–2000 and 2000–2003. Conversion of orchard land, grassland and construction land was dominant in 1990–1995, whereas the conversion of farmland to forest land mainly occurred in 2000–2003. The results suggested a profound transition in institutional policy and political economy of land management, including implementation of integrated soil erosion control projects, adoption of a market-oriented economy and the ‘Grain-for-Green’ policy, during this period in China. To achieve long-term sustainable land use in Hengshan County, efforts should aim at increasing off-farm income of rural families as well as establishing land-economizing mechanisms to promote land productivity, in addition to conservation measures.

关键词： Hengshan County land management per capita land area policy sustainable land use

The Effect of Administration of Rutin on Plasma Levels of Estrogen, Prolactin, Growth Hormone and Gene Expression of Their Receptors in Mammary Glands in Ovariectomized Rats

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Journal of Integrative Agriculture 2012年第10期11卷 1700-1706页

作者： guo xu-dong DIAO Qi-yu WANG Yue-ying TU Yan DENG Kai-dong WANG Xin-jian FU Tong YAN Gui-long Key Laboratory of Feed Biotechnology Ministry of Agriculture/Feed Research Institute Chinese Academy of Agricultural Sciences Key Laboratory of Animal Growth and Development Ministry of Agriculture/Henan Agricultual University College of Animal Sciences Jinling Institute of Technology College of Animal Sciences Hebei North University

The development of mammary glands, endocrine hormone concentrations and the gene expression of related receptors were measured in ovariectomized virgin rats after adminstration of an estrogen-like plant extract, rutin. Thirty-two ovariectomized virgin Wistar rats were randomly assigned to 4 treatments with 8 animals each： gastric infusion of 2 mL normal saline per unovariectomized rat per day （Sham）, gastric infusion of 2 mL normal saline per ovariectomized rat per day （Ova）, gastric infusion of 60 mg rutin kg-1 body weight （BW） per ovariectomized rat per day （Ova＋Rut）, or intramuscular injection of 60 ug estradiol kg-1 BW per ovariectomized rat weekly （Ova＋Est）. Samples of blood and mammary glands were harvested to determine the levels of estrogen （E2）, prolactin （PRL） and growth hormone （GH）, and the gene expression of estrogen receptors （ER）, prolactin receptors （PRLR） and growth hormone receptors （GHR） with radioimmunoassy （RIA） and RT-PCR technology, respectively. The E2 concentration in plasma and gland tissues from the rats of Ovx＋Rut or Ovx＋Est was higher than that of Ovx （P〈0.05）, but the plasma E2 concentration from the rats of Ovx＋Rut was lower than that of Sham （P〈0.05）. The order of the PRL concentration in plasma and gland tissues was Ovx〈Ovx＋Rut〈Ovx＋Est 〈Sham, and the difference in each treatment （P〈0.05）. The plasma GH concentration was lower in Ovx than in Ovx＋Rut or Ovx＋Est, and lower in Ovx＋Rut than in Sham （P〈0.05）. The GH concentration in gland tissues was lower in Ovx than in Ovx＋Rut or Ovx＋Est （P〈0.05）, and lower in Ovx＋Rut than in Sham （P〈0.05）. The gene expression of ER in gland tissues was increased in an order as Ovx〈Ovx＋Rut〈Ovx＋Est〈Sham （P〈0.05）, and PRLR, GHR showed the same trend. In conclusion, adminstration of rutin increased the E2 concentration in plasma and mammary glands, promoted pituitary PRL and GH release, up-regulated the gene expression of ER, PRLR and GHR, and stimulated mammary development in ovariectomized virgin rats.

关键词： rutin rats mammary gland development hormones receptors

Effects of pulse magneto-oscillation on GCr15 bearing steel continuous casting billet

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Journal of Iron and Steel Research International 2022年第1期29卷 144-150页

作者： Yan-jie Liu guo-dong xu Ying-chun Wang Hong-gang Zhong Li-juan Li Biao Wang Qi-jie Zhai Materials Genome Institute Shanghai UniversityShanghai 200444China Center for Advanced Solidification Technology Shanghai UniversityShanghai 200444China Research Institute China Baowu Steel Group CorporationShanghai 200431China Steel Plant China Baowu Steel Group CorporationShanghai 200431China

Pulse magneto-oscillation(PMO)added during solidification could affect the solidification structure and macrosegregation.A modified thermal simulation equipment was applied to prepare GCr15 bearing steel continuous casting billets with different PMO peak ***,metallographic analysis,component analysis and numerical simulation were adopted to study the influence of PMO peak current and its *** sample with 150 K_(I)A PMO peak current treatment has little difference with the samples without PMO treatment on solidification structure and *** the peak currents are 250 and 350 K_(I)A,the columnar zone increases and macrosegregation *** 450 K_(I)A peak current is selected,the equiaxed grain ratio is enlarged,and the dendritic grains are refined,and the macrosegregation of C,Cr,Si and Mn is decreased *** analyzing,different convections induced by PMO with various peak currents are the key factor to change the solidification structure and macrosegregation.

关键词： Bearing steel Numerical simulation Thermal simulation Pulse magneto-oscillation

Down-regulation of eIF5A-2 prevents epithelial-mesenchymal transition in non-small-cell lung cancer cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第6期14卷 460-467页

作者： guo-dong xu Xin-bao SHI Le-bo SUN Qing-yun ZHOU Da-wei ZHENG Huo-shun SHI Yong-liang CHE Zi-shan WANG guo-feng SHAO Department of Thoracic & Cardiovascular Surgery Lihuili HospitalNingbo Medical CenterAffiliated Hospital of Medical SchoolNingbo University Department of Thoracic & Cardiovascular Surgery Ningbo First HospitalAffiliated Hospital of Medical SchoolNingbo University

Background:Epithelial-mesenchymal transition(EMT) is believed to be the critical process in malignant tumor invasion and metastases,and has a great influence on improving the survival rate in non-small-cell lung cancer(NSCLC) *** studies suggested that eukaryotic initiation factor 5A-2(eIF5A-2) might serve as an adverse prognostic marker of *** detected eIF5A-2 in NSCLC A549 cells,and found that the invasive capability correlates with the eIF5A-2 ***:Transforming growth factor(TGF)-β1 was used to induce EMT in A549 *** blotting,immunofluorescence,wound healing assay,and transwell-matrigel invasion chambers were used to identify phenotype *** blotting was also used to observe changes of the expression of *** down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and *** tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion ***:After stimulating with TGF-β1,almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion *** cells also had higher eIF5A-2 protein ***-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities ***:The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells,which correlated with enhanced tumor invasion and metastatic ***,in the A549 cell line,the process of EMT phenotype change could be reversed by eIF5A-2 siRNA,with a consequent weakening of both invasive and metastatic capabilities.

关键词： Non-small-cell lung cancer(NSCLC) Epithelial-mesenchymal transition(EMT) Eukaryotic initiation factor 5A-2(eIF5A-2) Transforming growth factor(TGF)-β1 A549

Transumbilical single-incision laparoscopic hepatectomy： an initial report

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Chinese Medical Journal 2011年第5期124卷 787-789页

作者： HU Ming-gen ZHAO guo-dong xu Da-bing LIU Rong Department of Hepatobiliary Surgery Chinese People's Liberation Army General Hospital Beijing 100853 China

Transumbilical single-incision laparoscopic surgeries have attracted the attention of surgeon. Here we report a patient with multiple hepatic hemagiomas and symptomatic cholelithiasis who underwent laparoscopic left lateral hepatecomy and left hepatic hemangioma enucleation with single incision followed by cholecystectomy. The duration of the operation was 155 minutes and the blood loss was 100 ml. There were no complications during or after the treatment. This surgical treatment yields a good cosmetic effect and rapid recovery.

关键词： transumbilical single-incision laparoscopic surgery natural orifice endoscopic surgery laparoscopic hepatectomy

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胶囊内窥镜无线遥测定位的校正

光学精密工程 2010年第12期18卷 2650-2655页

作者：郭旭东严荣国颜国正上海理工大学医疗器械与食品学院上海200093 上海交通大学电子信息与电气工程学院上海200240

为了进一步提高采用交流励磁定位无线跟踪胶囊内窥镜的定位精度,减小系统误差,提出了改进的神经网络定位校正方法。首先,设计了适应于胶囊内窥镜定位校正的神经网络结构;然后,采用Levenberg-Marquart算法结合贝叶斯正则化方法改进校正网... 详细信息

为了进一步提高采用交流励磁定位无线跟踪胶囊内窥镜的定位精度,减小系统误差,提出了改进的神经网络定位校正方法。首先,设计了适应于胶囊内窥镜定位校正的神经网络结构;然后,采用Levenberg-Marquart算法结合贝叶斯正则化方法改进校正网络,抑制校正网络的过拟合。通过定位实验平台,建立了定位目标的跟踪位置与实际位置的样本对照数据表,并应用校正网络对定位数据进行校正。定位校正实验表明,改进的神经网络校正法可进一步减小定位误差,校正后的X,Y,Z,α,β分量的平均误差分别减小至8.7 mm,10.1 mm,7.3 mm,0.086 rad和0.081 rad。与基本BP算法相比,采用Levenberg-Marquart贝叶斯正则化的改进算法有效提高了定位校正网络的泛化能力和收敛精度。

关键词：胶囊内窥镜无线定位交流励磁神经网络校正贝叶斯正则化

Feasibility of Localizing in vivo Micro-devices with Electromagnetic Methods

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Journal of Shanghai Jiaotong university(Science) 2008年第5期13卷 559-561页

作者：郭旭东颜国正姜萍萍 School of Electronic Information and Electrical Engineering Shanghai Jiaotong University

In order to measure the location of medical micro-devices in the gastrointestinal tract, electro-magnetic methods were developed considering the magnetic permeability of human bodies. Two varieties of electromagnetic localization methods have been implemented: one uses direct current(DC) to generate the elec-tromagnetic field, and the other uses alternating current (AC). The two varieties of the localization principle were analyzed and relevant experiments were made. The experiments show that the alternating electromagnetic method acquires higher accuracy, higher stability and wider measurement range.

关键词： medical micro-devices position measurement electromagnetic field

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao Qin dong Dan Zou Zhijun Yang Lili guo Ruxiang xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

Relationship between Carotid Atherosclerosis and Cerebral Infarction

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Chinese Medical Sciences Journal 2010年第1期25卷 32-37页

作者： Guang-wen Li Guan-yi Zheng Jin-guo Li xu-dong Sun Department of Geriatrics Union Hospital Fujian Medical University Fuzhou 350001 China

Objective To study the relationship between carotid atherosclerosis and cerebral infarction (CI). Methods Between November 2008 and March 2009,147 CI patients (CI group) and 48 patients with non-cerebrovascular diseases (control group) were enrolled from inpatients of Neurology Department of our hospital. The diagnostic criterion of thickened carotid intima was set as 1.0 mm≤intima-media thickness (IMT) 0.05). Conclusions Carotid atherosclerosis is to some extent able to reveal the atherosclerotic condition of cerebral arteries and act as an important predictor for the risk of CI. T

关键词： carotid atherosclerosis cerebral infarction intima-media thickness color Doppler ultrasonography