首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1542篇
  免费   92篇
  2024年   8篇
  2023年   41篇
  2022年   16篇
  2021年   18篇
  2020年   64篇
  2019年   83篇
  2018年   90篇
  2017年   88篇
  2016年   76篇
  2015年   60篇
  2014年   59篇
  2013年   205篇
  2012年   118篇
  2011年   87篇
  2010年   84篇
  2009年   78篇
  2008年   82篇
  2007年   79篇
  2006年   60篇
  2005年   34篇
  2004年   18篇
  2003年   29篇
  2002年   23篇
  2001年   13篇
  2000年   19篇
  1999年   9篇
  1998年   6篇
  1997年   7篇
  1996年   7篇
  1995年   5篇
  1994年   4篇
  1993年   7篇
  1992年   3篇
  1991年   1篇
  1990年   1篇
  1988年   1篇
  1987年   1篇
  1985年   7篇
  1984年   6篇
  1983年   8篇
  1982年   7篇
  1981年   5篇
  1980年   5篇
  1979年   9篇
  1978年   3篇
排序方式: 共有1634条查询结果,搜索用时 15 毫秒
71.
以中国社会科学引文索引(CSSCI)为操作平台,以核心作者群的被引论著为样本,对样本篇数、篇次、作者、机构、地域分布、主题分布、年代分布等因素进行了引文分析和量化的描述,并从文献的角度对大陆华侨华人研究现状进行评估。结果表明:大陆华侨华人研究1993—2002年是高峰期,形成了以福建、北京、广东为主的核心作者群,高等院校仍是华侨华人研究的主要机构,研究主题以经济、社会、历史为主,学术论文的利用率不高,高水平的研究成果不多。华侨华人研究在学术界的整体影响力不大,某些不够科学和规范的引证态度和方法亟需改进。  相似文献   
72.
宁明花山岩画区危岩体稳定研究   总被引:1,自引:1,他引:0  
花山岩画区的危岩体的存在严重危及古岩画的保存和游客的安全,使得旅游业遭到重创。为了对区内危岩体状态做出评价,并为其后期治理工程提供依据,通过对岩画区的环境地质条件和病害成因的调查,结合危岩体的形态和结构特征,分析得出了区内危岩体崩塌破坏的三种模式为倾倒式崩塌、错断式崩塌和拉裂式崩塌,并提出了不同破坏模式的力学模型。应用极限平衡法对不同破坏模式的危岩体进行了稳定性计算分析,得出区内危岩体大部分处于欠稳定状态,须进行治理。最后提出了危岩体的防治原则与措施。  相似文献   
73.
为了克服传统的有损文物分析技术对文物造成的破坏,研制出一种简易光导纤维反射光谱仪。建立了光导纤维反射光谱技术对颜料分析鉴定的基本方法,提供了一种简捷的文物颜料无损分析鉴定的新技术。通过对西安、重庆等地彩绘文物颜料成分的鉴定,表明光导纤维反射光谱法测量结果准确、可靠,在文物颜料鉴定等方面具有广阔的应用前景。  相似文献   
74.
袁书琪  刘丽 《旅游科学》2007,21(4):8-11
海峡西岸旅游产业在全国和亚太地区占有重要地位,旅游产业结构布局的调整有重大意义.当前海峡西岸旅游产业偏重观光游览,旅游投入偏少;偏重自然景观,旅游文化发掘不够;偏重旅行消费,旅游六要素不完备;偏重旅游旺季,时间上经营不平衡;偏重低级竞争,市场无序现象还比较严重.旅游产业布局存在旅游集散地与目的地错位、星散布局缺乏整合、重复布局分散客流、单体布局缺乏联系等问题.海峡西岸旅游产业结构布局调整应集中精力抓准重点,延长产业链,设计旅游精品,调整布局构建多级布局体系.  相似文献   
75.
Ethnoarchaeology appears nowadays as a poorly formulated field. However, it could become a real science of reference for interpreting the past if it was focused upon well-founded cross-cultural correlates, linking material culture with static and dynamic phenomena. For this purpose, such correlates have to be studied in terms of explanatory mechanisms. Cross-cultural correlates correspond to those regularities where explanatory mechanisms invoke universals. These universals can be studied by reference to the theories found in the different disciplines they relate to and which are situated outside of the domain of archaeology. In the domain of technology, cross-cultural correlates cover a wide range of static and dynamic phenomena. They allow the archaeologist to interpret archaeological facts—for which there is not necessarily analogue—in terms of local historical scenario as well as cultural evolution. In this respect, it is shown that ethnoarchaeology, when following appropriate methodologies and focussing on the universals that underlie the diversity of archaeological facts, does provide the reference data needed to climb up in the pyramid of inferences that make up our interpretative constructs.  相似文献   
76.
ABSTRACT. Although researchers have deconstructed the myth of stark social differences between the various North American sub‐societies, an assimilating American melting pot and an ethnically oppressive monocultural Québec are still popular representations within Canadian majority discourses, such as the English‐language mainstream media and parts of academia. In this paper, I argue that images of ‘America’ and ‘Québec’ play important roles for the multicultural reconstruction of Canadian nationhood. Examining selected op‐ed articles from two Toronto‐based mainstream newspapers during the 1990s, I develop and exemplify a theoretical understanding of how national identities are constituted and transformed within inter‐ and intra‐national relations of power and alterity. I pay special attention to the particularisation of Canada through the confrontation with American nationhood, the ambiguities of recognising the distinctiveness of Québec inside Canada, and the consequences of projecting Québec's supposedly ‘ethnic’ nationalism outside the boundaries of Canadianness.  相似文献   
77.
Osteoarthritis is a major health concern in living populations, as well as being one of the most common pathological lesions identified in the archaeological record. The aetiology of the disease remains unclear, with a multi‐factorial influence of physical strain, age, genetics, and obesity. Previous studies have identified a relationship between the presence of knee osteoarthritis on the distal femoral joint and the morphology of the intercondylar notch, patellar groove, and medial condyle. The current study expands this research to investigate the relationship between distal femoral, distal humeral, and proximal ulnar joint morphology and osteoarthritis with 3D shape analysis techniques. These methods provide a more detailed analysis of joint morphology in order to determine any relationship between 3D shape and osteoarthritis. The results indicate a complex relationship between joint shape and knee osteoarthritis, with eburnated right femora showing a statistically significant association. The shapes associated with eburnated or affected femoral joints can be explained by osteophyte development, and therefore likely represent systematic shape changes and not a particular joint shape predisposing individuals to the condition. There was no identifiable relationship found in the proximal ulna or distal humerus, indicating that joint shape is unlikely to influence the development of the condition in the elbow joint and that any shape changes produced by osteoarthritis are not systematic or quantifiable. The joints analysed in this study were highly influenced by asymmetry, sexual dimorphism, and allometry, resulting in a small sample size of affected joints in many datasets. Further analyses of large skeletal samples are needed to more thoroughly investigate the possible relationship of distal femoral joint shape and osteoarthritis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
78.
The skeletal remains of 18 individuals interred at the ancient Maya site of Caledonia (100 to 1000 C.E.), located in the Cayo District of Belize, w ere sampled for stable carbon and nitrogen isotope analysis in order to reconstruct their diet. Stable carbon and nitrogen isotope ratios in 18 bone collagen samples and stable carbon isotope ratios in bioapatite from 15 bone and 6 tooth enamel samples were assessed. Small sample sizes precluded the assessment of dietary variation with respect to age, sex, social status or time period among the Caledonia Maya. However, the sampled individuals consumed a varied diet consisting of maize, supplemented with some C3 plants, terrestrial herbivores and/or lower order freshwater resources such as snails and molluscs and possibly maize‐fed animals. This dietary variability with an emphasis on maize is unsurprising given the biological diversity surrounding the site and the known importance of this crop to the ancient Maya. As expected, the isotopic values from Caledonia are similar to those from nearby sites from similar time periods. However, four individuals exhibit a marine dietary signature, possibly indicating inland trade of marine resources from coastal sites, or the migration of coastal people to Caledonia. This study demonstrates the validity of sampling small, fragmented collections from minor Maya centres in order to gain valuable insight into ancient Maya dietary practices. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
79.
阿勒泰地区位于新疆的最北端,与欧亚草原之间存在丰富的文化交流,而冶金技术的发展与人类文明紧密相关,为探究新疆阿勒泰地区的冶金发展情况,选取9件草原游牧文化的代表性器物——铜鍑和马具,使用金相显微镜、扫描电子显微镜和X射线能谱仪及双通道电感耦合等离子体发射光谱仪,对16个样品进行金相组织分析和成分分析,并探讨其制作技术特征。研究发现阿勒泰地区的早期铁器时代铜器普遍采用范铸工艺,其成分主要为红铜、砷铜、铅砷青铜。该分析结果为研究新疆阿勒泰地区的冶金发展提供了重要参考。  相似文献   
80.
The number of studies using trace elements as indicators of diet has increased with time, but the majority have used few elements and a small sample. The present study has as a principal objective a multi-element analysis of diet in a large sample in which diagenetic changes have been shown to be unimportant. The analysis was made using concentrations of seven elements—Sr, Ba, Mg, Cu, Zn, V and Ca—in 197 individuals from the necropolis of ‘S' Illot des Porros’ (Majorca, Spain). The results show that these individuals would have had a mixed diet with a high meat component, principally of marine origin (molluscs and fish), but with an important consumption of seeds and cereals and a low proportion of vegetables.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号