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   160篇
  免费   3篇
  2023年   1篇
  2021年   3篇
  2020年   3篇
  2019年   2篇
  2018年   3篇
  2017年   9篇
  2016年   10篇
  2015年   2篇
  2014年   2篇
  2013年   34篇
  2012年   11篇
  2011年   7篇
  2010年   11篇
  2009年   13篇
  2008年   12篇
  2007年   4篇
  2006年   6篇
  2005年   4篇
  2004年   3篇
  2003年   4篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1997年   2篇
  1996年   2篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1988年   2篇
  1985年   1篇
  1983年   1篇
  1978年   1篇
排序方式: 共有163条查询结果,搜索用时 15 毫秒
31.
32.
The Levant of the fourth millennium B.C. was scattered with numerous small farming communities. The agricultural activities were based on growing barley, wheat, lentils, and fruit trees. This was accompanied by raising sheep-goats, pigs, and cattle and occasionally using marine resources. The architecture and the thick accumulation of debris loaded with pottery refuse indicate that the sites were sedentary and occupied for long periods. The social organization of these communities does not seem to have been very complex. The evidence argues against the existence of hierarchies and high-status social units that had the power to dominate and permanently regulate production and distribution. The evidence of religious activities also indicates that a priesthood, if it existed, was not dominant in the regulation of social and economic activities. The rapid cultural changes in the Levant during the late fourth and early third millennium were probably caused by the impact of the events in Egypt and Mesopotamia. The local modifications were readjustments to the large-scale changes in the Near East which influenced the rural and provincial Levantine Chalcolithic societies.  相似文献   
33.
The stable carbon and nitrogen isotope ratios of collagen of seven bones from each of three rabbits raised on a monotonous diet, and of two bones from each of eight female and seven male mink raised on another monotonous diet, were determined. The ranges of δ13C values and δ15N values were 0·5‰ and 0·6‰ for the rabbit bones and 1·0‰ and 1·4‰ for the mink bones. Uncertainties in the δ13C and δ15N values for prehistoric human diets estimated from the isotopic composition of collagen from the small numbers of bones which are typically available for analysis, and thus likely to be of the order of ±1‰.  相似文献   
34.
During the late Longshan period (ca. 4200–3900 BP) settlements on the Central Plains of China underwent a diversification in food production technologies, which set the stage for rapid economic and social development. The introduction of novel domesticates such as rice, wheat, cattle, and sheep not only provided more food choices, but also changed ideas concerning land use, farming techniques, and the use and mobilization of large scale labor forces. To better understand the contribution that these new dietary items and practices made to shaping the late Longshan period societies, a stable isotope ratio study of humans (n = 12) and animals (n = 42) was conducted at the late Longshan period site of Wadian. The human δ13C and δ15N values are clustered into two distinct groups. One group of nine individuals (δ13C = −9.9 ± 0.7‰; δ15N = 7.5 ± 0.5‰) had a predominately C4 diet based on millet grains with little protein input from the domestic animals. The other group of three individuals (δ13C = −14.3 ± 0.8‰; δ15N = 10.2 ± 0.3‰) had a mixed C3/C4 diet of millets and rice and were consuming sheep and cattle. The animals also displayed dietary diversity with the pigs (δ13C = −11.3 ± 2.5‰; δ15N = 6.9 ± 1.0‰, n = 10) and dogs (δ13C = −10.1 ± 1.0‰; δ15N = 7.2 ± 1.1‰, n = 7) having mostly a C4 plant based diet (millets). In contrast, the cattle (δ13C = −12.8 ± 2.1‰; δ15N = 7.6 ± 0.7‰, n = 9), sheep (δ13C = −16.7 ± 0.9‰; δ15N = 7.6 ± 0.1‰, n = 2), and cervids (δ13C = −20.8 ± 0.9‰; δ15N = 5.0 ± 1.2‰, n = 10) had diets with a greater contribution from C3 sources such as rice and wild plants. The discovery that humans and animals had different subsistence patterns indicates dietary complexity at Wadian and that rice agriculture, and cattle and sheep husbandry practices were already an important part of the local economy by the late Longshan period in the southern region of the Central Plains of China. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
35.
This article explores the living conditions and specifically the possible etiologies of subperiosteal reactions among those seafarers who did not survive Christopher Columbus' second voyage to the Americas and died at La Isabela, the first permanent European settlement in the New World, which is located in the present‐day Dominican Republic. The town was founded in 1494 by Christopher Columbus (1451–1506) and occupied for only 4 years. This study analyses the macroscopic and histological evidence of the skeletal series excavated from this contact cemetery, which is presently curated at the Museo del Hombre Dominicano. Twenty of the 27 systematically scored individuals reveal subperiosteal bone accretions, and in at least 15 individuals, these accretions appear bilaterally. The morphology, distribution and healing stages of the majority of these lesions provide new, direct evidence suggesting severe adult scurvy, a condition caused by sustained vitamin C deprivation, which was common among seafarers before the 18th century. The historical context surrounding the individuals' death at the European contact settlement and the conditions and duration of Christopher Columbus' second transatlantic voyage to the New World represent key elements in the interpretation of these lesions. In this case, the evidence also corroborates the known failure of Columbus' crew to exploit the locally available foods rich in vitamin C. Scurvy probably contributed significantly to the outbreak of sickness and collective death within the first months of La Isabela's settlement, an aspect that inflects the current discussion about the degree of virulence of New World infections that decimated the European newcomers, who we conclude to have been already debilitated and exhausted by scurvy and general malnutrition. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
36.
This paper presents evidence for increased recovery of organic residues from archaeological pottery through use of a microwave‐assisted liquid chromatography protocol. C16:0 and C18:0 saturated fatty acids were obtained from archaeological potsherds recovered from nine Neolithic settlements in the Middle East dating between 4700 and 7300 cal bc , including materials that had not produced evidence for the survival of any lipid species through use of ‘conventional’ solvent extraction techniques. Compound‐specific isotopic analyses of C16:0 and C18:0 fatty acids in potsherd extracts subsequently revealed δ13C/δ12C compositions consistent with modern subcutaneous fats of wild boar and goats pastured on lands adjacent to the Jordan Valley, and residues from a modern pottery vessel used in the manufacturing of butter, cheese and yogurt in central Turkey. These results are presented as an illustration of capabilities of the microwave‐assisted recovery protocol. The reclamation of saturated and unsaturated fatty acids from archaeological pottery fragments recovered from a number of the earliest ceramic horizons in the Middle East is herewith reported, and the extraction methods and instrumental analytical techniques are described.  相似文献   
37.
This paper presents the results of a multi-isotopic (oxygen, strontium, carbon and nitrogen isotopes) investigation of population and dietary diversity in Roman Gloucester, focusing on individuals found in a late 2nd century AD mass burial pit at London Road, and comparing them to those found in the nearby cemetery. There were no statistical differences in isotopic composition between mass grave and cemetery burials, suggesting, in agreement with the osteological evidence, that the mass burial was the result of a catastrophic event, probably an epidemic disease. Strontium and oxygen isotope analysis demonstrated considerable diversity in the origins of the Gloucester population, with evidence for both UK and non-UK individuals. Diet was predominately terrestrial and similar to that of other Romano-British populations. Elevated δ13Cdentine ratios in some individuals are correlated with raised δ18Op values and are therefore probably due to childhoods spent in warmer climates, rather than dietary variation.  相似文献   
38.
文明起源是世界范围内的重大学术课题,夏、商、周三代是中国文明起源研究的关键阶段之一,但传世文献的确切记载只能上推到841BC.为此,国家设立重大科研项目--"夏商周断代工程",以期解决841 BC以前的夏、商、周三代纪年断代问题.  相似文献   
39.
Jet has been widely used in the past for jewellery but was just one of a range of black lithic materials employed. When worked into small objects these materials can be visually indistinguishable, yet discrimination is important because of the restricted occurrence of jet. X-ray fluorescence (XRF) is a rapid non-destructive discriminatory technique, but not all samples are clearly classified, and inhomogeneity may pose problems. A reassessment of the use of XRF is reported. Other techniques considered include electron spin resonance, infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, scanning electron microscopy and X-radiography. These were tested on geological materials to define an effective methodology for archaeological material. The recommended approach is a combination of XRF and X-radiography, although preliminary Fourier transform infrared results showed promise. The X-ray techniques were tested on Romano-British assemblages from Catterick and Stanwick.  相似文献   
40.
Sections of human hair from naturally desiccated Sudanese Nubian mummies representing X-Group (AD 350-550) and Christian (AD 550-1300) periods in the Wadi Halfa area have been analysed for their isotope ratios. Because the carbon in hair represents food intake over the growth period of this tissue, analysis comparing segments taken next to the scalp with those further along the shaft can indicate diet just prior to death as well as any recent shift in food consumption. Modern populations in this area practise seasonal crop scheduling which involves the cultivation of C3 plants (wheat, barley and most fruits and vegetables) in the winter and the hardier C4 plants (sorghum and millet) in the summer. Shifting isotopic values along the length of hair strands of the ancient inhabitants of this area demonstrate that this practice has its roots at least as far back as the Initial Phase of Intensive Agriculture. The most common season of death appears to have been summer, the time of greatest climatic, nutritional and physiological stress for both ancient and modern inhabitants.  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