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   5234篇
  免费   252篇
  2023年   39篇
  2020年   109篇
  2019年   111篇
  2018年   188篇
  2017年   193篇
  2016年   217篇
  2015年   138篇
  2014年   138篇
  2013年   1523篇
  2012年   167篇
  2011年   196篇
  2010年   178篇
  2009年   147篇
  2008年   119篇
  2007年   113篇
  2006年   123篇
  2005年   81篇
  2004年   59篇
  2003年   65篇
  2002年   71篇
  2001年   76篇
  2000年   67篇
  1999年   81篇
  1998年   62篇
  1997年   44篇
  1996年   36篇
  1995年   49篇
  1994年   35篇
  1993年   50篇
  1992年   33篇
  1991年   43篇
  1990年   47篇
  1989年   42篇
  1988年   33篇
  1987年   44篇
  1986年   47篇
  1985年   47篇
  1984年   52篇
  1983年   47篇
  1982年   41篇
  1981年   47篇
  1980年   42篇
  1979年   39篇
  1978年   36篇
  1977年   36篇
  1975年   27篇
  1974年   27篇
  1973年   29篇
  1972年   29篇
  1970年   27篇
排序方式: 共有5486条查询结果,搜索用时 15 毫秒
941.
942.
One of the most important pre-Columbian gold assemblages made up of more than one hundred objects from two tombs in the Cauca river valley, Colombia, was studied to obtain archaeometric information. Although several attempts have been made to arrange gold production in time and space from the stylistic point of view, no firm conclusions were possible due to the lack of archaeological contexts. This paper presents first results of a new, fully instrumental approach, in which different analytical techniques, including OM, SEM-EDS, XRF, PIXE, RBS, AMS and X-ray imaging, were applied in order to determine a technological, metallurgical and chronological frame of the so-called Quimbaya Treasure.  相似文献   
943.
In the present work we attempt to recover endogenous ancient DNA from cereal grains preserved under different conditions: charred, partially charred and waterlogged. A total of 126 grains from naked wheat and 18 from barley from different sites on the Eastern Iberian Peninsula ranging from the beginning of agriculture in the region to the turn of the Common Era, were studied. Two different extraction protocols were used, a standard phenol–chloroform method and a silica-based DNA extraction procedure implemented for artificially charred seeds. Amplifications were directed to three markers: the large subunit of ribulose 1,5 biphosphate carboxylase (rbcL) and the microsatellite WCT12 in the chloroplast genome and the x and y subunits of the high molecular weight glutenin gene (Glu-1) in the nucleus. The first two were used to assess the preservation status of the samples, while with the third we tried to identify the wheat grains at species level. It was possible to obtain eleven positive amplifications in 8 partially charred seeds but only two amplifications of the Glu-1 gene from a single sample of the Early Bronze age were genome-specific. Different contamination sources were identified and reported. Cloning and alignment of sequenced clones showed a correspondence of the amplified fragment to modern wheat D genome haplotypes. This result suggests that the sample corresponds to hexaploid wheat (Triticum aestivum L.), thus being the first ancient DNA evidence to date for the cultivation of hexaploid wheat in the prehistoric agriculture of the Iberian Peninsula. Moreover, obtained results highlight contamination problems associated to the study of ancient archaeobotanical charred seeds suggest that the combination of a silica-based extraction method together with the amplification of specific targets is a good strategy for recovering endogenous ancient DNA from this kind of material.  相似文献   
944.
The archaeological reconstruction of ancient states requires consistent regional measures of state-directed power and influence. This paper presents data from a series of systematic archaeological surveys in the Cusco region of highland Peru to evaluate patterns of influence by the Wari state during a period of colonization from ca. AD 600–1000. We discuss interpretive debates over the nature and intensity of Wari social power, suggesting that site-based studies can be contextualized meaningfully using our large-scale dataset, which offers settlement patterns at varying distances (0–70 km) from Pikillacta, a Wari administrative center. We discuss local settlement patterns before and during Wari colonization, as well as the distribution of Wari pottery and local Wari-influenced wares. We then use a geographic information systems analysis of travel time from key sites to evaluate the broad regional distribution patterns of local and Wari ceramic styles. Although the regional survey data do not inform us reliably about all kinds of social power, we conclude that the Wari cultural, economic, and political influence over the Cusco region was limited and discontinuous—an example of colonization that resembles the practices of other early states.  相似文献   
945.
Imperial strategies varied as the Inca expanded their empire from the capital in Cusco. Some communities were conquered violently while others were ruled indirectly with little evidence of Inca presence. According to ethnohistorical evidence, the central coast was peacefully annexed by the Incas ca. A.D. 1470, but little is known about how Inca imperialism may have affected the quality of life of subjects of the Inca Empire. We integrate multiple lines of evidence to assess diet, health and disease for a sample of human remains from the Late Horizon cemetery of Puruchuco-Huaquerones, Peru. Specifically, we examine and analyze osteological, dental and stable isotope data (n = 162, 90 and 46 respectively) in order to investigate whether the Inca period population at Puruchuco-Huaquerones experienced nutritionally insufficient diets and poor health under imperial policies. Diet at Puruchuco-Huaquerones incorporated a variety of foods, both plant and animal. Osteological lesions and stature indicate periods of stress, with males experiencing more illness relative to females. Stature sexual dimorphism, the presence of healed lesions and isotope data indicate a sufficiently nutritious diet and support the conclusion that, although disease was present, individuals were healthy enough to survive and recover. Geographical and temporal comparisons suggest that health changed little with the Inca annexation of this region, but future work is needed.  相似文献   
946.
Reviews     
ROBERT J. YOUNG. French Foreign Policy, Nineteen Eighteen to Nineteen Forty-Five: A Guide to Research and Research Materials, ed. Christoph M. Kimmich. Wilmington, Delaware: Scholarly Resources Inc., 1981. Pp. xv, 242. $17.50 (US). Reviewed by A.S. Kanya-Forstner

CHRISTOPH M. KIMMICH. German Foreign Policy, Nineteen Eighteen to Nineteen Forty Five: A Guide to Research and Research Materials. Wilmington, Delaware: Scholarly Resources Inc., 1981. Pp. ix, 293. $17.50 (US). Reviewed by Ulrich Trumpener

ALAN CASSELS. Italian Foreign Policy, Nineteen Eighteen to Nineteen Forty- Five: A Guide to Research and Research Materials, ed. Christoph M. Kimmich. Wilmington, Delaware: Scholarly Resources Inc. 1981. Pp. xi, 271. $17.50 (US). Reviewed by Peter C. Kent

VOJTECH MASTNY. Russia's Road to the Cold War: Diplomacy, Warfare, and the Politics of Communism, 1041–1945. New York: Columbia University Press, 1979. Pp. xix, 409. $16.95 (US). Reviewed by Teddy J. Uldricks

R. KEITH SCHOPPA. Chinese Elites and Political Change: Zhejiang Province in the Early Twentieth Century. Cambridge, Mass.: Harvard University Press, 1982. Pp. 280. $30.00 (US). Reviewed by J. Shrecker

EDWARD M. SPIERS. Haldane: An Army Reformer. Edinburgh: Edinburgh University Press, 1980. Pp. vi, 240. £10.00. Reviewed by John E. Kendle

IAN NISH, ed. Anglo-Japanese Alienation, 1919–1952: Papers of the Anglo-Japanese Conference on the History of the Second World War. New York: Cambridge University Press, 1982. Pp. 320. $37.50. Reviewed by Ray Jones

JOHN C. G. RÖHL and NICOIAS SOMBART, eds. Kaiser Wilhelm II: New Interpretations. Cambridge: Cambridge University Press, 1982. Pp. 319. $39.50 (US). Reviewed by Konrad H. Jarausch

ROBIN FISHER and J.M. BUMSTED, eds. An Account of a Voyage to the Northwest Coast of America in 1785 and 1786 by Alexander Walker. Vancouver: Douglas & McIntyre; Seattle: University of Washington Press, 1982. Pp. 319. $24.95. Reviewed by Christon I. Archer

ERIK P. HOFFMANN and ROBBIN F. LAIRD. The Politics of Economic Modernization in the Soviet Union. Ithaca, NY: Cornell University Press, 1982. Pp. 215. $19.50 (US). Reviewed by Cyril E. Black

WERNER G. HAHN. Postwar Soviet Politics. The Fall of Zhdanov and the Defeat of Moderation, 1946–53. Ithaca and London: Cornell University Press, 1982. Pp. 243. $19.50 (US). Reviewed by Richard K. Debo

VICTOR ROTHWELL. Britain and the Cold War, 1941–1947. London: Jonathan Cape, 1982. Pp. 551. £16. Reviewed by Gerald Jordan

DAN P. SILVERMAN. Reconstructing Europe after the Great War. Cambridge, MA: Harvard University Press, 1982. Pp. vii, 347. $25.00 (US). Reviewed by Keith L. Nelson  相似文献   
947.
948.
949.
950.
Abstract

F EWER COLD WAR myths are more enduring in the United Kingdom than that of ‘Buster’ Crabb. In April 1956, Britain’s Secret Intelligence Service (SIS) coaxed Commander Lionel ‘Buster’ Crabb, a naval frogman from the Second World War, out of retirement to dive under the Soviet cruiser Ordzhonikidze, while it was docked in Portsmouth. It had brought the Soviet Premier Nikolai Bulganin and the First Secretary of the Communist Party, Nikita S. Khrushchev, to the United Kingdom on a state visit. The operation, routine by all accounts, ended in both personal and diplomatic failure. Fourteen months later, the decomposed body of a frogman washed up in Chichester harbour. Despite the British government’s hope that the discovery might be the end of the affair, it fired up the conspiracy theorists, who alleged that the body could not be Crabb’s; that, in fact, he had been kidnapped, taken to the Soviet Union, and renamed Korablev.1 The government did little to dispel such myths. A few days after Crabb’s disappearance, The Times succinctly summed up the situation: ‘official reticence about the activities which led to the death of Commander Crabb has caused much speculation.’2 Curiosity was further piqued a few days later when the prime minister, Sir Anthony Eden, stated m the house of commons on 9 May that ‘it would not be in the public interest to disclose the circumstances in which Commander Crabb is presumed to have met his death.’3  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