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GIS-based analysis of forest degradations in Baihe Forestry Bureau,northeast China

Science China(Technological Sciences) 2006年第z1期49卷 167-176页

作者： ZHOU Li, DAI Limin , Guofan Shao, XU Dong, WANG Hui & BAI Jianwei Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate university of Chinese Academy of Sciences, Beijing 100101, China department of Forestry and Natural Resources, Purdue university, West Lafayette, IN 47907, usa department of city Development, Jinan university, Jinan 2.0002. China Academy of Forest Inventory and Planning, State Forestry Administration, Beijing 100714, China 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. Graduate university of Chinese Academy of Sciences Beijing 100101 China 3. department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA 4. department of city Development Jinan University Jinan 250002 China 5. Academy of Forest Inventory and Planning State Forestry Administration Beijing 100714 China

Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2.00 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.

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Astragalus polysaccharide reduces hepatic endoplasmic reticulum stress and restores glucose homeostasis in a diabetic KKAy mouse model

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Acta Pharmacologica Sinica 2007年第12期28卷 1947-1956页

作者： Xian-qing MAO~2.Yong WU~3,Ke WU~2.Ming LIU~2.Jing-fang ZHANG~4,Feng ZOU~2.Jing-ping OU-YANG~(2.5)~2.department of Pathophysiology,Medical College of Wuhan university,Hubei Provincial Key Laboratory of Allergy and Immune-RelatedDiseases,Wuhan 430071,China ~3 Division of Endocrinology and Diabetes,department of Medicine,university of Oklahoma Health ScienceCenter,Oklahoma city,Oklahoma 73104,usa ~4 department of Pathology and Physiology,Jingmen Vocational College,Jingmen 448000,China department of Pathophysiology Medical College of Wuhan UniversityHubei Provincial Key Laboratory of Allergy and Immune-Related DiseasesWuhan 430071China Division of Endocrinology and Diabetes Department of MedicineUniversity of Oklahoma Health Sc

Aim:To examine the potential effects of Astragalus polysaccharide （APS） onhepatic endoplasmic reticulum （ER） stress in vivo and in vitro and its link withhypoglycemia activity,thus establishing the mechanism underlying the hypogly-cemic action of ***:The obese and type 2.diabetic KKAy mousemodel,which is the yellow offspring of the KK mice expressed Aygene (700mg·kg-1·d-1,8 weeks) and a high glucose-induced HepG2.cell model （2.0 μg/mL,2. h）were treated with *** oral glucose tolerance test was measured to reflexinsulin sensitivity with the calculated homeostasis model assessment （HOMA-IR） *** 1 （XhoI site-binding protein 1） transcription and splicing,an indica-tor of ER stress,was analyzed by RT-PCR and real-time *** expression andactivation of glycogen synthase kinase 3 beta （GSK3β）,an insulin signaling protein,was measured by Western ***:APS can alleviate ER stress in cul-tured cells in *** hyperglycemia status,systemic insulin sensitivity,fattyliver disease,and insulin action in the liver of diabetic mice were partly normalizedor improved in response to APS ***:Our results indicatethat APS enables insulin-sensitizing and hypoglycemic activity at least in part byenhancing the adaptive capacity of the ER,which can further promote insulinsignal ***,APS has promising application in the treatment of type2.diabetes.

关键词： Astragalus membranaceus polysaccharide type 2.diabetes mellitus insulin resistance endoplasmic reticulum stress

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DQDB-ATM MAN:一种新的局域网-ATM网互连方案

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计算机工程与应用 2002年第4期38卷 174-176,185页

作者：汪小涓续敏 Electrical Engineering Dept. 山东曲阜师范大学电教系曲阜273165

文章提出了一种新的局域网-ATM互连方案(分布式队列双总线子网)和相应的流量控制算法,这里称为“基于信用的流量控制”。该算法既能够在保持数据优先级的前提下按照传输请求的时序进行网络传输,又有效地防止了ATM缓冲区溢出。

关键词：局域网 ATM网网络互连 DQDB 异步传输模式

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Delay-induced Quasi-Consensus in Multi-agent Dynamical Systems

Delay-induced Quasi-Consensus in Multi-agent Dynamical Syste...

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第二十九届中国控制会议

作者： YU Wenwu1,CHEN Guanrong1,REN Wei2.1.department of Electronic Engineering,city {2. of Hong Kong,Hong Kong,P.R.China2.department of Electrical and Computer Engineering,utah State {2.,usa

This paper studies delay-induced quasi-consensus in multi-agent dynamical systems.A linear consensus protocol in second-order dynamics is designed where both the current and delayed position information is *** time delay,in a common perspective,can induce periodic oscillations or even chaos to dynamical ***,it is surprisingly found in this paper that quasi-consensus in a multi-agent system cannot be reached without the delayed position information under the given protocol while it can be achieved with a relatively small time delay by appropriately choosing the coupling strength.A necessary and sufficient condition for reaching quasi-consensus in multi-agent dynamical systems is then *** is further shown that quasi-consensus can be achieved if and only if the time delay is less than a critical value which depends on the coupling strengths and the largest eigenvalue of the Laplacian matrix of the ***,a simulation example is given to illustrate the theoretical analysis.

关键词： Multi-Agent System Delay-Induced Consensus Quasi-Consensus Algebraic Graph Theory

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Neuroprotection of Insulin against Oxidative Stress-induced Apoptosis in Cultured Retinal Neurons:Involvement of Phosphoinositide 3-kinase/Akt Signal Pathway

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Acta Biochimica et Biophysica Sinica 2006年第4期38卷 241-248页

作者： Xiao-Rui YU~(1,2.) Guo-Rong JIA~1 Guang-Dao GAO~3 Shu-Hong WANG~1 Yan HAN~1 Wei CAO~4 1 department of Biochemistry and Molecular Biology, 2.Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education, 3 department of Pathobiology,School of Medicine,Xi'an Jiaotong {2.,Xi'an 710061,China 4 department of Ophthalmology,{2. of Oklahoma Health Science Center,Dean A,McGee Eye Institute,Oklahoma city,Oklahoma 73104,usa departmentofBiochemistryandMolecularBiology KeyLaboratoryofEnvironmentandGenesRelatedtoDiseasesofMinistryofEducation departmentofPathobiology SchoolofMedicineXi'anJiaotongUniversityXi'an710061China

In order to investigate the neuroprotection of insulin in retinal neurons,we used retinal neuronalculture as a model system to study the protective effects of insulin against H2.2.induced cytotoxicity andapoptotic *** retinal neuronal cultures were grown from retinas of 0-2.day old *** viability was measured by 3-（4,5-dimethylthiazol-2.yl）-2.5-diphenyl-tetrazolium bromide *** cell death was evaluated by the TdT-mediated digoxigenin-dutP nick-end labeling assay,and byDNA laddering *** 3-kinase （PI3K） activity was measured using phosphoinositide4,5-bisphophate and [γ-32.]ATP as *** blot analysis with anti-phospho-Akt （pS473） antibodywas performed to examine the level of phosphorylated *** observed that treatment with 100μM H2.2.or 2. h significantly decreased cell viability and induced apoptotic death of retinal neurons,and that pretreatmentwith 10 nM insulin significantly inhibited or attenuated H2.2.induced cytotoxicity and *** LY2.4002.a specific PI3K inhibitor,abolished the cytoprotective effect of *** also stronglyactivated both PI3K and the downstream effector *** results suggest that insulin protects retinalneurons from oxidative stress-induced apoptosis and that the PI3K/Akt signal pathway is involved in insulin-mediated retinal neuroprotection.

关键词： apoptosis insulin phosphoinositide 3-kinase/Akt oxidative stress neuroprotection retinal neuronal culture

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增加前肢主动运动对去势大鼠桡、尺骨骨量的影响

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广东医学院学报 2000年第3期18卷 235-236页

作者：刘浩宇姚蔚 WebsterS.S.Jee Rebecca SetterbergRadiobiology Division university of utah salt lake city {2. usa 广东医学院生化学教研室 Radiobiology Division UniversityofUtahSaltLakeCityUtah84102USA Radiobiology Division University of UtahSalt Lake CityUtah84102USA

目的 :建立雄性大鼠前肢主动运动模型并观察其对去势雄性大鼠尺、桡骨骨量减少的影响。方法 :建立前肢主动运动取食动物模型并去势以观察尺骨、桡骨部位骨量的影响。6月龄大鼠按体重随机分为 5组。(1 )对照组 ;(2.)假手术组 +正常高度笼... 详细信息

目的 :建立雄性大鼠前肢主动运动模型并观察其对去势雄性大鼠尺、桡骨骨量减少的影响。方法 :建立前肢主动运动取食动物模型并去势以观察尺骨、桡骨部位骨量的影响。6月龄大鼠按体重随机分为 5组。(1 )对照组 ;(2.)假手术组 +正常高度笼 ;(3)双侧睾丸切除组 +正常高度笼 ;(4)假手术组 +模型组 ;(5)双侧睾丸切除组 +模型组。结果 :模型组大鼠的尺、桡骨骨皮质都有显著增加。结论 :大鼠前脚趾掌主动运动对远端尺骨和远端桡骨有良好的作用 ,可有效地防止雄性去势大鼠相应部位的骨量丢失。

关键词：前肢主动运动尺骨桡骨骨质疏松骨量

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Exo+ proofreading polymerases mediate genetic analysis and its application in biomedical studies

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Acta Pharmacologica Sinica 2005年第3期26卷 302-306页

作者： Duan-fang LIAO~2.Lin-ling CHEN~2.Cui-ying PENG~2.Jia ZHANG~2.Kai LI~(2.3,4)2.Division of Pharmacogenomies,SNP Institute,School of Life Science,Nanhua university,Hengyang 42.001,China 3 department of Human Genetics,{2. of Hope National Medical Center,Duarte,CA,usa DivisionofPharmacogenomics SNPInstituteSchoolofLifeScienceNanhuaUniversityHengyang421001China

Polymerases with a proofreading function in their internal 3′ to 5′ exonucleasepossess high fidelity for DNA replication both in vivo and in *** obstaclefacing Exo+ polymerases for single nucleotide polymorphism （SNP） detection couldbe bypassed by using primer-3′-termini *** hypothesis has beenwell tested using three types of modified allele specific primers with:3′ labeling,3′to 5′exonuclease resistance,and 3′***,three new SNPassaying methods have been developed to carry out genome-wide genotyping,taking advantage of the enzymatic properties of Exo+*** newmutation detection assays are widely adaptable to a variety of platforms,includ-ing multi-well plate and microarray *** ofExo+polymerasesto genetic analysis,including genotyping that is mostly relevant to pharma-cogenetics,high-fidelity gene expression profiling,rare mutation detection andmutation load assay,will help to accelerate the pace of personalized *** review paper,we will first introduce three new assays that we have recentlydeveloped,and then describe a number of their applications in pharmacogeneticsand in other biomedical studies.

关键词： single nucleotide polymorphism DNA primers DNA-directed DNA polymerase

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MICRORNA REGULATION OF TISSUE FACTOR EXPRESSION IN BREAST CANCER CELLS

MICRORNA REGULATION OF TISSUE FACTOR EXPRESSION IN BREAST CA...

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2.10’全国肿瘤分子标志及应用学术研讨会暨第五届中国中青年肿瘤专家论坛

作者： department of Pathology,university of Oklahoma Health Sciences Center,Oklahoma {2., Oklahoma 73104,usa

Objectives:Tissue factor has been well-recognized as an important regulator of tumor angiogenesis and metastasis independent from its blood coagulation *** tissue factor gene is highly expressed in breast cancer cells with invasive potential,and the mechanisms regulating tissue factor gene expression in these cells remain *** present study examined the hypothesis that microRNA regulation of

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Uniform attractors of non-autonomous dissipative semilinear wave equations

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Progress in Natural Science:Materials International 2003年第2期 22-30页

作者： LI Kaitai and ZHAO Chunshan (School of Science, Xi'an Jiaotong university, Xi'an 710049, China . department of Mathematics, the university of Iowa, Iowa city, IA 52.42. usa) School of Science Xi'an Jiaotong University Xi'an 710049 China department of Mathematics the University of Iowa Iowa City IA 52242 USA

The asymptotic long time behaviors of a certain type of non-autonomous dissipative semilinear wave equations are studied . The existence of uniform attractors is proved and their upper bounds for both Hausdorff and Fr... 详细信息

关键词： semilinear wave equations uniform attractor Hausdorff and Fractal dimensions.

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Role of oxyR from Sinorhizobium meliloti in Regulating the Expression of Catalases

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Acta Biochimica et Biophysica Sinica 2005年第6期37卷 421-428页

作者： Li EUO~(1.3) Ming-Sheng QI~(1.3) Shi-Yi YAO~2.Hai-Ping CHENG~2.Jia-Bi ZHU~1 Guan-Qiao YU~1 1 National Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences.Chinese Academy of Sciences, Shanghai 2.0032. China 2.Biological Sciences department, Lehman College, the city {2. of New York, Bronx, NY 10468. usa, 3 Graduate School of the Chinese Academy of Sciences, Shanghai 2.0032. China NationalLaboratoryofPlantMolecularGenetics InstituteofPlantPhysiologyandEcologyShanghaiInstitutesforBiologi

The process of symbiotic nitrogen fixation results in the generation of reactive oxygen speciessuch as the superoxide anion（O2.）and hydrogen peroxide（H2.2..The response of rhizobia to these toxicoxygen species is an important factor in nodulation and nitrogen *** Sinorhizobium meliloti,oneoxyR homologue and three catalase genes,katA,katB,and katC were detected by sequence *** gene is located next to and divergently from katA on the *** investigate the possible rolesof oxyR in regulating the expression of catalases at the transcriptional level in ***,an insertion mutantof this gene was *** mutant was more sensitive and less adaptive to H2.2.han the wild typestrain,and total catalase/peroxidase activity was reduced approximately fourfold with the OxyR mutationrelative to *** activities of KatA and KatB and the expression of katA::lacZ and katB::lacZ promoterfusions were increased in the mutant strain compared with the parental strain grown in the absence of H2.2.indicating that katA and katB are repressed by ***,when exposed to H2.2.katA expressionwas also increased in both *** and Escherichia *** exposed to H2.2.OxyR is convertedfrom a reduced to an oxidized form in *** concluded that the reduced form of OxyR functions as arepressor of katA and katB ***,in the presence of H2.2.reduced OxyR is converted to theoxidized form of OxyR that then results in increased katA *** further showed that oxyR expressionis autoregulated via negative feedback.

关键词： Sinorhizobium meliloti OxyR catalase katA H2.2

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