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The prognostic molecular markers in hepatocellular carcinoma 被引量:163
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作者 Lun-Xiu Qin Zhao-You Tang,Liver Cancer Institute and Zhongshan Hospital,Fudan University,Shanghai,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期385-392,共8页
The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to ... The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to death. With new discoveries in cancer biology, the pathological and biological prognostic factors of HCC have been studied quite extensively. Analyzing molecular markers (biomarkers) with prognostic significance is a complementary method. A large number of molecular factors have been shown to associate with the invasiveness of HCC, and have potential prognostic significance. One important aspect is the analysis of molecular markers for the cellular malignancy phenotype. These include alterations in DNA ploidy, cellular proliferation markers (PCNA, Ki-67, Mcm2, MIB1, MIA, and CSE1L/CAS protein), nuclear morphology, the p53 gene and its related molecule MD M2, other cell cycle regulators (cyclin A, cyclin D, cyclin E, cdc2, p27, p73), oncogenes and their receptors (such as ras, c-myc, c-fms, HGF, c-met, and erb-B receptor family members), apoptosis related factors (Fas and FasL), as well as telomerase activity. Another important aspect is the analysis of molecular markers involved in the process of cancer invasion and metastasis. Adhesion molecules (E-cadherin, catenins, serum intercellular adhesion molecule-1, CD44 variants), proteinases involved in the degradation of extracellular matrix (MMP-2, MMP-9, uPA, uPAR, PAI), as well as other molecules have been regarded as biomarkers for the malignant phenotype of HCC, and are related to prognosis and therapeutic outcomes. Tumor angiogenesis is critical to both the growth and metastasis of cancers including HCC, and has drawn much attention in recent years. Many angiogenesis-related markers, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived endothelial cell growth factor (PD-ECGF), thrombospondin (TSP), angiogenin, pleiotrophin, and endostatin (ES) levels, as well as intratumor microvessel density (M 展开更多
关键词 Apoptosis CARCINOGENS Carcinoma Hepatocellular Cell Adhesion Cell Division Cell Nucleus Extracellular matrix Genes p53 Humans Liver Neoplasms Neovascularization Pathologic PLOIDIES Prognosis Proteome TELOMERASE Tumor Markers Biological
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Reduction Algorithms Based on Discernibility Matrix:The Ordered Attributes Method 被引量:130
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作者 王珏 王驹 《Journal of Computer Science & Technology》 SCIE EI CSCD 2001年第6期489-504,共16页
In this paper, we present reduction algorithms based on the principle of Skowron's discernibility matrix - the ordered attributes method. The completeness of the algorithms for Pawlak reduct and the uniqueness for... In this paper, we present reduction algorithms based on the principle of Skowron's discernibility matrix - the ordered attributes method. The completeness of the algorithms for Pawlak reduct and the uniqueness for a given order of the attributes are proved. Since a discernibility matrix requires the size of the memory of U2, U is a universe of objects, it would be impossible to apply these algorithms directly to a massive object set. In order to solve the problem, a so-called quasi-discernibility matrix and two reduction algorithms are proposed. Although the proposed algorithms are incomplete for Pawlak reduct, their opimal paradigms ensure the completeness as long as they satisfy some conditions. Finally we consider the problem on the reduction of distributive object sets. 展开更多
关键词 rough set theory principle of discernibility matrix inductive machine learning
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黄河三角洲景观组分判定与景观破碎化分析 被引量:99
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作者 布仁仓 王宪礼 肖笃宁 《应用生态学报》 CAS CSCD 1999年第3期321-324,共4页
以地理信息系统(ARC/INFO)为手段,利用遥感卫星图片(TM5)及其他相关图件,以地貌、土壤与植被作为景观分类指标,把黄河三角洲的景观分成8大类型,30个景观类型.在此基础上,以斑块的周长面积比值、相对面积及与其... 以地理信息系统(ARC/INFO)为手段,利用遥感卫星图片(TM5)及其他相关图件,以地貌、土壤与植被作为景观分类指标,把黄河三角洲的景观分成8大类型,30个景观类型.在此基础上,以斑块的周长面积比值、相对面积及与其他景观类型之间的空间相关关系作为识别基质的指标,判定黄河三角洲景观的基质是柽柳芦苇潮盐土斜平地景观;根据斑块的周长面积比值识别廊道,并进行定量化研究.采用斑块密度对黄河三角洲景观的破碎化进行分析,发现生态交错带内斑块密度大; 展开更多
关键词 景观结构 斑块密度 基质 廊道
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数字图像的二维Arnold变换及其周期性 被引量:95
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作者 邹建成 铁小匀 《北方工业大学学报》 2000年第1期10-14,共5页
以图像信息安全问题为背景 ,讨论了平面上 Arnold变换的周期性 。
关键词 ARNOLD变换 周期性 数字图像 图像信息安全 二维
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中药巴布剂制备工艺的实验研究 被引量:110
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作者 刘淑芝 费虹 +2 位作者 汤亚池 郭春燕 张蔚君 《中国实验方剂学杂志》 CAS 2001年第3期9-11,共3页
选用正交实验法 ,以膏体的均匀性、膜残留性、柔软性、可涂展性及对皮肤的追随性为综合考察指标 ,以剥离时粘着力 (180°)为量化指标 ,对影响巴布剂膏体物理性状的因素 :搅拌时间、炼合温度、各组分基质的添加顺序三个因素进行实验... 选用正交实验法 ,以膏体的均匀性、膜残留性、柔软性、可涂展性及对皮肤的追随性为综合考察指标 ,以剥离时粘着力 (180°)为量化指标 ,对影响巴布剂膏体物理性状的因素 :搅拌时间、炼合温度、各组分基质的添加顺序三个因素进行实验研究 ,并对最佳条件进行优选。结果表明 :制备工艺的最佳条件为 :搅拌 2 0~ 40min ;膏体温度 5 0℃ ;赋形剂组分先与填充剂组合混合后 ,再加入粘性剂。 展开更多
关键词 制备工艺 基质 正交设计 中药 巴布剂
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低渗透油藏裂缝动态渗吸机理实验研究 被引量:117
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作者 王家禄 刘玉章 +2 位作者 陈茂谦 刘莉 高建 《石油勘探与开发》 EI CAS CSCD 北大核心 2009年第1期86-90,共5页
根据低渗透油藏裂缝与基质交渗流动的理论模型和物理模型,建立了裂缝与基质之间动态渗吸的实验方法并就裂缝内驱替速度、油水黏度比、润湿性、初始含水饱和度等参数对动态渗吸效果的影响进行了实验研究。对于低渗透裂缝性油藏,在压力梯... 根据低渗透油藏裂缝与基质交渗流动的理论模型和物理模型,建立了裂缝与基质之间动态渗吸的实验方法并就裂缝内驱替速度、油水黏度比、润湿性、初始含水饱和度等参数对动态渗吸效果的影响进行了实验研究。对于低渗透裂缝性油藏,在压力梯度作用下水在裂缝内流动,同时由于毛细管力作用水渗吸到基质内,渗吸到基质中的水将油替换出来渗流到裂缝中,注入水再将裂缝中的油驱替到出口端,这就是裂缝与基质之间的交渗流动。动态渗吸实验结果表明:在本实验条件下,存在一个最佳驱替速度(3.0 mL/h),渗吸效率最高为35.5%;在一定的驱替速度范围内,由于毛细管力与黏性力的共同作用,渗吸效果最好。亲水岩心的动态渗吸效果最好。油水黏度比越小,动态渗吸效果越好。初始含水饱和度越高,毛细管力越小,动态渗吸效果越差。 展开更多
关键词 低渗透油藏 裂缝 基质 动态渗吸
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直观队列命名法的基本原理及其在矩阵与拓扑指数计算中的应用 被引量:102
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作者 胡黔楠 梁逸曾 +2 位作者 王亚丽 郭方遒 黄兰芳 《计算机与应用化学》 CAS CSCD 北大核心 2003年第4期386-390,共5页
提出了一种用于拓扑结构输入的直观队列命名法(HQN),该方法结合了二维联接表与线性命名输入法的优点。在直观队列命名法(HQN)中,原子用元素周期表中的字母表示,第一个字母用大写表示,第二个字母(如果存在)用小写表示。键由构成键的原子... 提出了一种用于拓扑结构输入的直观队列命名法(HQN),该方法结合了二维联接表与线性命名输入法的优点。在直观队列命名法(HQN)中,原子用元素周期表中的字母表示,第一个字母用大写表示,第二个字母(如果存在)用小写表示。键由构成键的原子的编号联接来表示,单键由构成键的原子的编号一次联接表示,双键由构成键的原子的编号二次联接表示,三键由构成键的原子的编号三次联接表示。将分子中的键按顺序输入,然后将对应的原子类型标识在该原子的号码之后,同时输入字符串中,从而可得一个分子结构的HQN编码。该方法由分子的二维图可直观地直接得到,分子的编码由分子中的键与原子一个个排列而成,因而起名为直观队列命名法。在MATLAB环境下,用Matlab调入每个分子的字符串编码,然后对该编码进行识别与操作,并计算了8种矩阵,以及26种共300多个拓扑指数。 展开更多
关键词 直观队列命名法 基本原理 矩阵 拓扑指数 计算 应用 图论 分子结构
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线性代数教学改革漫谈 被引量:99
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作者 李尚志 《教育与现代化》 2004年第1期30-33,共4页
本文介绍了作者在线性代数教学实践中的想法和做法 :1.课程主要内容 :空间为体 ,矩阵为用 ;2 .什么是抽象 ?抽象就是难得糊涂 ,就是从不同的事物中抓住共同点 ,忽略不同点 ;3.以解决问题为线索来组织教学内容。
关键词 线性代数 教学改革 教学内容 数学素养 数学教学 高校
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A new class of scrambling transformation and its application in the image information covering 被引量:78
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作者 齐东旭 邹建成 韩效宥 《Science China(Technological Sciences)》 SCIE EI CAS 2000年第3期304-312,共9页
This paper studies two kinds of nonlinear transformations, namely the higher-dimensional Arnold transformation and the higher-dimensional Fibonacci Q-transformation and discusses the scrambling action of the two trans... This paper studies two kinds of nonlinear transformations, namely the higher-dimensional Arnold transformation and the higher-dimensional Fibonacci Q-transformation and discusses the scrambling action of the two transformations focusing on the phase space of the digital images. A sufficient and necessary condition that a matrix transformation of digital image has periodicity is given. The results show that the two transformations have potential application in the storage and transportation of image information for the purpose of information security. 展开更多
关键词 digital IMAGE SCRAMBLING TRANSFORMATION ARNOLD TRANSFORMATION PERIODICITY FIBONACCI matrix cryptoguard of IMAGE information.
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Cellular and molecular mechanisms in the pathogenesis of liver fibrosis:An update 被引量:89
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作者 Gülsüm ?zlem Elpek 《World Journal of Gastroenterology》 SCIE CAS 2014年第23期7260-7276,共17页
There have been considerable recent advances towards a better understanding of the complex cellular and molecular network underlying liver fibrogenesis.Recent data indicate that the termination of fibrogenic processes... There have been considerable recent advances towards a better understanding of the complex cellular and molecular network underlying liver fibrogenesis.Recent data indicate that the termination of fibrogenic processes and the restoration of deficient fibrolytic pathways may allow the reversal of advanced fibrosis and even cirrhosis.Therefore,efforts have been made to better clarify the cellular and molecular mechanisms that are involved in liver fibrosis.Activation of hepatic stellate cells(HSCs)remains a central event in fibrosis,complemented by other sources of matrix-producing cells,including portal fibroblasts,fibrocytes and bone marrow-derived myofibroblasts.These cells converge in a complex interaction with neighboring cells to provoke scarring in response to persistent injury.Defining the interaction of different cell types,revealing the effects of cytokines on these cells and characterizing the regulatory mechanisms that control gene expression in activated HSCs will enable the discovery of new therapeutic targets.Moreover,the characterization of different pathways associated with different etiologies aid in the development of disease-specific therapies.This article outlines recent advances regarding the cellular and molecular mechanisms involved in liver fibrosis that may be translated into future therapies.The pathogenesis of liver fibrosis associated with alcoholic liver disease,non-alcoholic fatty liver disease and viral hepatitis are also discussed to emphasize the various mechanisms involved in liver fibrosis. 展开更多
关键词 Liver Liver fibrosis CIRRHOSIS FIBROGENESIS Hepatic stellate cells MYOFIBROBLAST Extracellular matrix
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Exploring the optimal operation time for patients with hypertensive intracerebral hemorrhage: tracking the expression and progress of cell apoptosis of prehematomal brain tissues 被引量:78
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作者 ZHANG Xin-qing ZHANG Zhi-min +3 位作者 YIN Xiao-liang ZHANG Kun CAI Hui LING Feng 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第10期1246-1250,共5页
Background Hypertensive intracerebral hemorrhage (HICH) is a severe disease with high morbidity and mortality. Timely removal of the hematoma through surgical procedures may effectively reduce secondary injuries. Ho... Background Hypertensive intracerebral hemorrhage (HICH) is a severe disease with high morbidity and mortality. Timely removal of the hematoma through surgical procedures may effectively reduce secondary injuries. However, there has long been a debate over the proper timing of such surgery. In this study, we explored the optimal operation time for HICH patients by observing the pathological changes in perihematomal brain regions during different stages of onset. Methods Twenty-five specimens of brain tissue, obtained from perihematomal region of HICH patients in different phases, were subjected to haematoxylin-eosin (HE) staining, terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) staining and Caspase-3, matrix metalloproteinases-9 (MMP-9) immunohistochemical staining. The changing roles of necrosis and apoptosis and the expression of MMP-9 and Caspase-3 positive cells were all observed using image analysis. Results The obvious expression of TUNEL positive cells was recognized within 6 hours of ICH onset, reaching its peak between 6 hours and 24 hours in the early phase. Results were highly consistent with Caspase-3 and MMP-9 positive cell counts. Necrosis was found 6 hours after ICH onset and aggravated after 12 hours. Conclusions In the early phase, apoptosis was seen as a major modality of injury in the brain tissue of the perihematomal region and was strongly correlated with the expression of MMP-9 and Caspase-3. The results of the present study suggest that an operation performed as soon as possible after ICH onset may be optimal for preserving the nervous system function. 展开更多
关键词 cerebral hemorrhage APOPTOSIS CASPASE-3 matrix metalloproteinases operations
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Attribute reduction theory and approach to concept lattice 被引量:73
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作者 ZHANG Wenxiu WEI Ling QI Jianjun 《Science in China(Series F)》 2005年第6期713-726,共14页
The theory of the concept lattice is an efficient tool for knowledge representation and knowledge discovery, and is applied to many fields successfully. One focus of knowledge discovery is knowledge reduction. This pa... The theory of the concept lattice is an efficient tool for knowledge representation and knowledge discovery, and is applied to many fields successfully. One focus of knowledge discovery is knowledge reduction. This paper proposes the theory of attribute reduction in the concept lattice, which extends the theory of the concept lattice. In this paper, the judgment theorems of consistent sets are examined, and the discernibility matrix of a formal context is introduced, by which we present an approach to attribute reduction in the concept lattice. The characteristics of three types of attributes are analyzed. 展开更多
关键词 formal context concept lattice attribute reduction discernibility matrix
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地震走时层析成像算法与比较 被引量:56
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作者 刘盛东 李承华 《中国矿业大学学报》 EI CAS CSCD 北大核心 2000年第2期211-214,共4页
采用物理数学方法,分析推导了离散层析成像的数值算法,介绍了其中的BPT法、ART法和SIRT法,并进行了数值模拟.结果表明:BPT方法相对简单,但概念明确;ART与SIRT方法属于迭代算法,迭代精度并不完全正比于迭代次数;但SIRT较ART方... 采用物理数学方法,分析推导了离散层析成像的数值算法,介绍了其中的BPT法、ART法和SIRT法,并进行了数值模拟.结果表明:BPT方法相对简单,但概念明确;ART与SIRT方法属于迭代算法,迭代精度并不完全正比于迭代次数;但SIRT较ART方法的迭代收敛性好、收敛速度快.以BPT方法的重建结果作为选代方法的初值,在投影数据精确时用ART方法,其它情况用SIRT方法,均能取得较为满意的重建结果图像. 展开更多
关键词 地震层析 图像重建 矩阵 层析成像 地震勘探
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组合预测误差信息矩阵研究 被引量:56
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作者 唐小我 《电子科技大学学报》 EI CAS CSCD 北大核心 1992年第4期448-454,共7页
研究组合预测误差信息矩阵的结构与组合预测方法性质之间的联系,首次提出冗余信息概念,对最优组合预测方法的组合结构进行了研究。
关键词 预测误差 信息 矩阵 预测方法
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我国农业废弃物资源化利用现状与发展趋势分析 被引量:69
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作者 刘振东 李贵春 +1 位作者 杨晓梅 尹昌斌 《安徽农业科学》 CAS 2012年第26期13068-13070,13076,共4页
论述了我国农业废弃物的特点和资源化综合利用的现状,分析了农业废弃物的资源潜力以及在资源化过程中的限制因素和技术瓶颈,并结合中国社会、经济发展的目标,提出农业废弃物循环利用思路及其政策建议。从农业废弃物资源化利用入手,推进... 论述了我国农业废弃物的特点和资源化综合利用的现状,分析了农业废弃物的资源潜力以及在资源化过程中的限制因素和技术瓶颈,并结合中国社会、经济发展的目标,提出农业废弃物循环利用思路及其政策建议。从农业废弃物资源化利用入手,推进生物基质产业化对于进一步解决环境污染和资源短缺、加快农业产业化进程和促进社会主义新农村具有重要意义。 展开更多
关键词 农业废弃物 资源化利用 基质化 循环利用理论
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Hepatic fibrosis: It is time to go with hepatic stellate cell-specifictherapeutic targets 被引量:63
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作者 Devaraj Ezhilarasan Etienne Sokal Mustapha Najimi 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第3期192-197,共6页
Hepatic fibrosis is a pathological lesion, characterized by the progressive accumulation of extracellularmatrix (ECM) in the perisinusoidal space and it is a major problem in chronic liver diseases. Phenotypicactiva... Hepatic fibrosis is a pathological lesion, characterized by the progressive accumulation of extracellularmatrix (ECM) in the perisinusoidal space and it is a major problem in chronic liver diseases. Phenotypicactivation of hepatic stellate cells (HSC) plays a central role in the progression of hepatic fibrosis. Retardation of proliferation and clearance of activated HSCs from the injured liver is an appropriate therapeuticstrategy for the resolution and treatment of hepatic fibrosis. Clearance of activated HSCs from the injuredliver by autophagy inhibitors, proapoptotic agents and senescence inducers with the high affinity towardthe activated HSCs may be the novel therapeutic strategy for the treatment of hepatic fibrosis in the nearfuture. 展开更多
关键词 Hepatic stellate cells APOPTOSIS AUTOPHAGY SENESCENCE Extracellular matrix
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加热器端差对机组热经济性影响的通用计算模型 被引量:55
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作者 张学镭 王松岭 +1 位作者 陈海平 万逵芳 《中国电机工程学报》 EI CSCD 北大核心 2005年第4期166-171,共6页
准确而快速地评价各级加热器端差的运行热经济性,对热力系统的设计、运行和检修具有十分重要的意义。文中以热力系统的热平衡方程、汽轮机功率方程和锅炉吸热量方程为基础,采用了将上述基本方程两端分别对加热器出口水焓求偏导的方法,... 准确而快速地评价各级加热器端差的运行热经济性,对热力系统的设计、运行和检修具有十分重要的意义。文中以热力系统的热平衡方程、汽轮机功率方程和锅炉吸热量方程为基础,采用了将上述基本方程两端分别对加热器出口水焓求偏导的方法,并针对不同型式的加热器,找出了公式的规律性,得到了分析加热器端差运行热经济性的通用计算模型。推导过程中,定义了端差等效焓降和端差等效吸热量系数两个重要的概念。计算实例表明:该模型具有计算结果准确、使用方便简捷、通用性强等特点,尤其适用于机组运行经济性在线监测系统。 展开更多
关键词 电厂 热力系统 加热器 机组 热经济性 通用计算模型
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基于矩阵的Apriori算法改进 被引量:43
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作者 李超 余昭平 《计算机工程》 CAS CSCD 北大核心 2006年第23期68-69,共2页
对基于矩阵的Apriori算法进行了改进,同时改进了发现关联规则算法,将Apriori算法的剪枝与矩阵联系起来,可以大大减少扫描数据库的次数,从而提高算法的效率,在生成关联规则中,利用了概率论的基本性质也大大减少了计算量。并通过实例说明... 对基于矩阵的Apriori算法进行了改进,同时改进了发现关联规则算法,将Apriori算法的剪枝与矩阵联系起来,可以大大减少扫描数据库的次数,从而提高算法的效率,在生成关联规则中,利用了概率论的基本性质也大大减少了计算量。并通过实例说明它是一种有效的关联规则挖掘方法。 展开更多
关键词 关联规则 APRIOFI算法 矩阵
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Design, Preparation and Properties of Carbon Fiber Reinforced Ultra-High Temperature Ceramic Composites for Aerospace Applications: A Review 被引量:59
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作者 Sufang Tang Chenglong Hu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第2期117-130,共14页
Carbon fiber reinforced ultra-high temperature ceramic (UHTC) composites, consisting of carbon fibers embedded in a UHTC-matrix or a C-SiC-UHTC-matrix, are deemed as the most viable class of materials that can overc... Carbon fiber reinforced ultra-high temperature ceramic (UHTC) composites, consisting of carbon fibers embedded in a UHTC-matrix or a C-SiC-UHTC-matrix, are deemed as the most viable class of materials that can overcome the poor fracture toughness and thermal shock resistance of monolithic UHTC ma- terials, and also improve the oxidation resistance and ablation resistance of C/C and C/SiC composites at ultra-high temperatures. In this review, we summarize the different processing routes of the compos- ites based on the UHTC introducing methods, including chemical vapor infiltration/deposition (CVI/D), precursor infiltration and pyrolysis (PIP), reactive melt infiltration (RMI), slurry infiltration (SI). in-sito reaction, hot pressing (HP), etc; and the advantages and drawbacks of each method are briefly dis- cussed. The carbon fiber reinforced UHTC composites can be highly tailorable materials in terms of fiber. interface, and matrix. From the perspective of service environmental applications for engine propul- sions anti hypersonic vehicles, the material designs (mainly focusing on the composition, quantity, structure of matrix, as well as the architecture of carbon fibers, UHTCs and pores), their relevant processing routes and properties (emphasizing on the mechanical and ablation properties) are discussed in this paper. In addition, we propose a material architecture to realize the multi-function through changing the distri- bution of carbon fibers, UHTCs and pores, which will be an important issue for future development of carbon fiber reinforced UHTC composites. 展开更多
关键词 Carbon fiber composites Ceramic matrix composites (CMC) Ultra-high temperature ceramic (UHTC) Ablation
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从景观生态学构建城市旅游开发与规划的操作模式 被引量:29
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作者 李蕾蕾 《地理研究》 CSSCI CSCD 北大核心 1995年第3期69-73,共5页
本文尝试建立一个关于旅游开发与规划的应用理论模式,以兼顾理论的抽象性和操作性。模式的构建依据地理空间分析方法,同时借用景观生态学斑、廊、基的概念。文中详细论述了该斑廊基网络结构操作模式的基本特点、变换空间分析方法等运... 本文尝试建立一个关于旅游开发与规划的应用理论模式,以兼顾理论的抽象性和操作性。模式的构建依据地理空间分析方法,同时借用景观生态学斑、廊、基的概念。文中详细论述了该斑廊基网络结构操作模式的基本特点、变换空间分析方法等运行机制,并以不同城市旅游规划、设计实例说明三大操作块的功能和操作意义。 展开更多
关键词 景观生态学 城市 旅游开发 规划 操作模式
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