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软件学报 1999年第2期10卷 175-180页

作者：张玉平北京航空航天大学计算机科学与工程系

搜索算法的初始空间、搜索策略、搜索过程可以用一阶语言描述，搜索算法的逻辑性质由初始状态空间确定．这意味着描述搜索过程的逻辑具有紧致性，初始状态的初等类具有有限封闭性．

关键词：搜索算法一阶逻辑逻辑分析人工智能

Neuronal firing in the globus pallidus internus and the ventrolateral thalamus related to parkinsonian motor symptoms

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Chinese Medical Journal 2009年第19期122卷 2308-2314页

作者： CHEN Hai ZHUANG ping zhang yu-qing LI Jian-yu LI Yong-jie Beijing Institute of Functional Neurosurgery Department of Neurology Xuanwu Hospital Capital Medical University Beijing 100053 China

Background It has been proposed that parkinsonian motor signs result from hyperactivity in the output nucleus of the basal ganglia, which suppress the motor thalamus and cortical areas. This study aimed to explore the neuronal activity in the globus pallidus internus （GPi） and the ventrolateral thalamic nuclear group （ventral oral posterior/ventral intermediate, Vop/Vim） in patients with Parkinson＇s disease （PD）. Methods Twenty patients with PD who underwent neurosurgery were studied. Microelectrode recording was performed in the GPi （n=10） and the Vop/Vim （n=10） intraoperatively. Electromyography （EMG） contralateral to the surgery was simultaneously performed. Single unit analysis was carried out. The interspike intervals （ISI） and coefficient of variation （CV） of ISI were calculated. Histograms of ISI were constructed. A unified Parkinson＇s disease rating scale （UPDRS） was used to assess the clinical outcome of surgery. Results Three hundred and sixty-three neurons were obtained from 20 trajectories. Of 175 GPi neurons, there were 15.4% with tremor frequency, 69.2% with tonic firing, and 15.4% with irregular discharge. Of 188 thalamic neurons, there were 46.8% with tremor frequency, 22.9% with tonic firing, and 30.3% with irregular discharge. The numbers of three patterns of neuron in GPi and Vop/Vim were significantly different （P 〈0.001）. ISI analysis revealed that mean firing rate of the three patterns of GPi neurons was （80.9±63.9） Hz （n=78）, which was higher than similar neurons with 62.9 Hz in a normal primate. For the Vop/Vim group, ISI revealed that mean firing rate of the three patterns of neurons （n=95） was （23.2±17.1） Hz which was lower than similar neurons with 30 Hz in the motor thalamus of normal primates. UPDRS indicated that the clinical outcome of pallidotomy was （64.3±29.5）%, （83.4±19.1）% and （63.4±36.3）%, and clinical outcome of thalamotomy was （92.2±12.9）%, （68.0±25.2）% and （44.3±7.2）% for tremor, rigidity and bradykinesia, respectively. A sign

关键词： Parkinson's disease movement disorders globus pallidus thalamus microelectrodes

Effects of Plant Density and Nitrogen Application Rate on Grain Yield and Nitrogen Uptake of Super Hybrid Rice

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Rice science 2009年第2期16卷 138-142页

作者： LIN Xian-qing ZHU De-feng CHEN Hui-zhe zhang yu-ping State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 China

The nitrogen uptake, yield and its components for two super-high-yielding hybrid rice combinations, Guodao 6 and Eryou 7954 were investigated under different plant densities （15, 18, and 21 plants/m^2） and different nitrogen application rates （120, 150, 180, and 210 kg/hm^2）. The experiment was conducted on loam soil during 2004-2006 at the experimental farm of the China National Rice Research Institute in Hangzhou, China. In these years, the two hybrid rice cleady showed higher yield at a plant density of 15 plants/m^2 with a nitrogen application rate of 180 kg/hm^2. Guodao 6 produced an average grain yield of 10 215.6 kg/hm^2 across the three years, while the yield of Eryou 7954 was 9 633.0 kg/hm^2. With fewer plants per unit-area and larger plants in the plots, the two hybrid rice produced more panicles per plant in three years. The highest nitrogen uptake of the two hybrid rice was at a plant density of 15 plants/m^2 with a nitrogen application rate of 180 kg/hm^2. Further increasing nitrogen application rate was not advantageous for nitrogen uptake in super-high-yielding rice under the same plant density.

关键词： super-high-yielding cultivation hybrid rice grain yield nitrogen uptake plant density nitrogen application rate

Sex-determining Region of Y Chromosome-related High-mobility-group Box 2 in Malignant Tumors： Current Opinions and Anticancer Therapy

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Chinese Medical Journal 2015年第3期128卷 384-389页

作者： Shi-Guang Cao Zong-Juan Ming yu-ping zhang Shuan-Ying Yang Department of Respiratory Medicine Second Affiliated HospitaL Xi'an Jiaotong University Xi'an Shaanxi 710004 China

Objective： To gain insight into the mechanism by which sex-determining region of Y chromosome （SRY）-related high-mobility-group box 2 （SOX2） involved in carcinogenesis and cancer stem cells （CSCs）. Data Sources： The data used in this review were mainly published in English from 2000 to present obtained from PubMed. The search terms were ＂SOX2,＂＂cancer,＂＂tumor＂ or ＂CSCs.＂ Study Selection： Articles studying the mitochondria-related pathologic mechanism and treatment of glaucoma were selected and reviewed. Results： SOX2, a transcription factor that is the key in maintaining pluripotent properties of stem cells, is a member of SRV-related high-mobility group domain proteins. SOX2 participates in many biological processes, such as modulation of cell proliferation, regulation of cell death signaling, cell apoptosis, and most importantly, tumor formation and development. Although SOX2 has been implicated in the biology of various tumors and CSCs, the findings are highly controversial, and information regarding the underlying mechanism remains limited. Moreover, the mechanism by which SOX2 involved in carcinogenesis and tumor progression is rather unclear yet. Conclusions： Here, we review the important biological functions of SOX2 in different tumors and CSCs, and the function of SOX2 signaling in the pathobiology ofneoplasia, such as Wnt/β-catenin signaling pathway, Hippo signaling pathway, Survivin signaling pathway, P13K/Akt signaling pathway, and so on. Targeting towards SOX2 may be an effective therapeutic strategy for cancer therapy.

关键词： Anticancer Therapy Cancer Cancer Stem Cell Signaling Sex-determining Region of Y Chromosome-related High-mobility-group Box 2

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振冲碎石桩加固软土地基试验研究

重庆建筑大学学报 2007年第6期29卷 57-61页

作者：余震张玉成张玉平武汉大学土木建筑工程学院武汉430072 北京师范大学地理学与遥感科学学院北京100875

以某水库拦河大坝地基处理工程为背景,介绍了振冲碎石桩加固软土地基的现场试验,并对碎石桩处理后复合地基的加固效果进行了检测分析,包括碎石桩桩体和桩间土以及桩土应力比等项的检测。最后综合重型动力触探试验、标准贯入试验、载荷... 详细信息

以某水库拦河大坝地基处理工程为背景,介绍了振冲碎石桩加固软土地基的现场试验,并对碎石桩处理后复合地基的加固效果进行了检测分析,包括碎石桩桩体和桩间土以及桩土应力比等项的检测。最后综合重型动力触探试验、标准贯入试验、载荷试验和土压力盒读数的检测结果得出：碎石桩对工程软土地基的处理能达到预期的加固效果,其复合地基承载力高于设计要求,抗液化能力明显提高,并且这种复合地基可以有效减小地基总沉降,加速地基的固结,具有良好的导水性;桩土应力比变化曲线呈上凸抛物线型,其值一般在1-4之间;碎石桩桩身附加应力随深度衰减很快,在接近桩底时,其附加应力几乎为零,所以在用碎石桩处理地基时应注意碎石桩的有效长度。该方法在随后进行的地基大面积加固中得到成功应用。

关键词：振冲碎石桩软土地基桩土应力比

Effect and mechanism of acute graft versus host disease on early diffuse murine lung injury following allogeneic stem cell transplantation

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Science China(Life Sciences) 2009年第11期52卷 1016-1022页

作者： NING Juan, LIU Qi Fa, LUO Xiao Dan, FAN Zhi ping & zhang yu Department of Hematology, Southern Hospital, Southern Medical University, Guang Zhou 510515, China 1. Department of Hematology Southern Hospital Southern Medical University Guang Zhou 510515 China

To explore the effect and pathogenssis of acute graft-versus-host disease (aGVHD) on early diffuse lung injury in allogeneic hematopoietic stem cell transplantation (allo-HSCT), we established an aGVHD model of C57BL/6→BALB/c mice. Chest computed tomography (CT) scans, histopathology and the levels of cytokines including tumor necrosis factor α (TNFα) and Interferon (IFNγ) in lungs were dynamically detected in recipient mice after transplantation. The incidence of aGVHD was respectively 0%, 0% and 100% in simple irradiation group (A), syngeneic transplant group(B) and allogeneic transplant group (C). Chest CT scans of recipient mice were normal in 3 groups on days +3 and +7 after transplantation. CT showed that two of ten mice had bilateral lung diffuse infiltrate on day +12 (on the brink of death) in group A and 6 of 10 mice had bilateral lung diffuse infiltrate on day +14 (3 d after aGVHD occurring) in group C, and were normal on days +12 and +14 in group B after transplantation. Histopathology of lungs in the 3 groups was similar, consisting of minor interstitial pneumonitis on day +3. Group A showed edema, hyperplasia of epithelial cells and widened alveolar interval on day +7, and epithelial cell necrosis, lymphocyte infiltration, hemorrhage, protein leakage, and local consolidation on day +12. The histopathology of group B showed slight edema of epithelial cells on +7 day, which were slighter than that on day +3, and virtually normal on day +14. The histopathology in group C was characterized by the significant expansion and congestion of capillaries, and lymphocyte infiltration on day +7, the acute pneumonitis was present involving tissue edema, lymphocyte and macrophage infiltration, protein leakage and perivascular inflammation on day +14. In group A, the levels of TNFα were lower on day +7 than on day +3. In group B, the levels of TNFα attained a peak on day +3, which decreased on days +7 and +14. In group C, the levels of TNFα were highest on day +7 and t

关键词： lung injury acute graft-versus-host disease allogeneic hematopoietic stem cell transplantation

Research on the Formation of Metal-Ceramic Surface Composite Coating by Wide-Band Laser Cladding

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材料热处理学报 2004年第05B期25卷 1025-1028页

作者： LIUShuo zhangWei-ping MAyu-tao DepartmentofMaterialsEngineering DatianUniversityofTechnologyDafianPeopte＇sRepublicofChina

Large-area in-situ synthesized TiB2(TiB, Fe2B)—Fe metal-ceramic composite coating has been fabricated on medium carbon steel by laser cladding with the optimal laser parameters and overlapping coefficient. The bonding interfaces between the cladding layer and the matrix and among different tracks are excellent. Microanalysis on the cladding layer shows that the morphology is a little different from each other and the element distribution and the mechanical properties are unanimous in each track while the mechanical property of the cladding layer shows a gradual change from the surface to the matrix. The in-situ separating out thin ceramic phases in the coating contribute to the improving of its properties greatly.

关键词：宽带激光包覆金属陶瓷显微结构机械性质

非完全信息环境中一种基于隐马尔科夫的博弈式功率控制机制

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电子学报 2016年第12期44卷 3004-3010页

作者：朱江张玉平重庆邮电大学重庆市移动通信重点实验室重庆400065

针对非完全信息环境下认知无线网络中的分布式功率控制问题,根据不同非授权用户对信道检测结果的差异,以及信道检测结果的非独立性,提出了一种基于隐马尔科夫模型的功率博弈机制.非授权用户可利用该模型推测其它非授权用户是否参与博弈... 详细信息

针对非完全信息环境下认知无线网络中的分布式功率控制问题,根据不同非授权用户对信道检测结果的差异,以及信道检测结果的非独立性,提出了一种基于隐马尔科夫模型的功率博弈机制.非授权用户可利用该模型推测其它非授权用户是否参与博弈,从而提升了博弈的信息准确度,使得非授权用户能够选择更优的发射功率.仿真表明,该功率控制机制在保证通信质量的前提下能够获得更大的容量功率比,具有更好的功率效率.

关键词：非完全信息隐马尔科夫博弈式功率控制

Strong Converse Inequalities for Certain Mixed Szász-Beta Operators

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Chinese Quarterly Journal of Mathematics 2011年第1期26卷 152-158页

作者： QI Qiu-lan zhang yu-ping College of Mathematics and Information Science Hebei Normal UniversityShijiazhuang 050016China Department of Mathematics Mechanical Engineering CollegeShijiazhuang 050003China

In this paper,a strong converse inequality of type B in terms of a new Kfunctional Kλα f,t2(0 < α < 2,0 ≤λ≤ 1) for certain mixed Szász-Beta operators is *** this inequality,the converse theorem can be obtained ... 详细信息

关键词： Szász-Beta operators K-functional strong converse inequality Hlder inequality

Advances in early diagnosis and therapy of pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 128-135页

作者： Qiang Xu, Tai-ping zhang and yu-Pei ZhaoDepartment of General Surgery, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medial Sciences, Beijing 100730, China Department of General Surgery Peking Union Medical College Hospital Peking Union Medical College & Chinese Academy of Medial Sciences Beijing 100730 China

BACKGROUND: Pancreatic cancer remains a devastating disease with a 5-year survival rate of less than 5%. Recent advances in diagnostic methods and therapeutic approaches have increased the possibility of improving the existing poor prognosis. DATA SOURCES: English-language articles reporting early diagnosis and therapy of pancreatic cancer were searched from the MEDLINE and PubMed databases, Chinese-language articles were from CHKD (China Hospital Knowledge Database) RESULT: The current literature about pancreatic cancer was reviewed from three aspects: statistics, screening and early detection, and therapy. CONCLUSIONS: Early detection and screening of pancreatic cancer currently should be limited to high risk patients Surgical resection is the only curative approach available, with some recent improvement in outcomes. Gemcitabine has been a standard treatment during the last decade. Gemcitabine based combination treatment, especially combined with newer molecular targeted agents, is promising. The rationale for radiotherapy is controversial, but with the recent development of modern radiation delivery techniques, radiotherapy should be intensified. Patients with borderline pancreatic cancer could benefit from neoadjuvant therapy but more evidence is needed and the best neoadjuvant regimen is still to be determined.

关键词： pancreatic neoplasm early diagnosis biomarkers surgery adjuvant therapy neoadjuvant therapy borderline resectable tumor