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   337篇
  免费   14篇
  2023年   4篇
  2022年   1篇
  2020年   9篇
  2019年   9篇
  2018年   9篇
  2017年   27篇
  2016年   18篇
  2015年   9篇
  2014年   9篇
  2013年   63篇
  2012年   13篇
  2011年   10篇
  2010年   5篇
  2009年   9篇
  2008年   12篇
  2007年   12篇
  2006年   6篇
  2005年   8篇
  2004年   9篇
  2003年   7篇
  2002年   12篇
  2001年   9篇
  2000年   7篇
  1999年   6篇
  1998年   10篇
  1997年   13篇
  1996年   10篇
  1995年   5篇
  1994年   5篇
  1992年   6篇
  1991年   1篇
  1990年   1篇
  1989年   3篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1982年   3篇
  1981年   1篇
  1980年   1篇
  1976年   2篇
  1973年   1篇
  1972年   1篇
排序方式: 共有351条查询结果,搜索用时 78 毫秒
251.
A likely case of tuberculosis in an Iron Age human burial from Dorset, England is described. Osteological examination and biomolecular study support the diagnosis. A radiocarbon determination indicates a date range for the burial of BC 400–230. This case represents the earliest reported case of tuberculosis from Britain, and indicates that the disease was present here prior to the Roman invasion. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
252.
Climate change is unusual compared with most environmental issues in the extent to which it has become accepted among orthodox policy institutions and public-and private-sector organizations. The authors explore the conditions that have led to the establishment of an epistemic community that brings together a broad array of actors, including the various NGOs, and the operational dimensions that define the participation of NGOs within the community. An epistemic community does not imply conformity of opinion or approach but allows for differentiation in terms of how its members construct the problem, and their objectives, core beliefs and favoured responses to climate change. Three broad styles of engagement through which NGOs contribute to this debate are identified: developing creative policy solutions, knowledge construction, and lobbying or campaigning. It should be noted that the authors refer primarily to development or environmental NGOs (ENGOs), though they do discuss business NGOs at a few points.  相似文献   
253.
The human right clavicle tends to be shorter than the left. A range of possible explanations can be advanced to account for this asymmetry. In the present work, clavicular morphology was studied in a medieval skeletal assemblage from Wharram Percy, England, with the aim of evaluating these competing explanations. At Wharram Percy, as anticipated, the right clavicle tended to be shorter. Patterns of asymmetry in curvature, robusticity, vascularization, and in the morphology of ligament and muscle attachment sites were also studied. The patterning in these data at Wharram Percy is consistent with inhibition of longitudinal growth of the clavicle on the dominant side due to lateral bias in mechanical loading, particularly in axial compression. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
254.
Rickets and osteomalacia are the subadult and adult expressions of a disease in which the underlying problem is a failure to mineralize bone protein (osteoid). The most common cause of this disease is a physiological deficiency in vitamin D. The associated problems include deformed bones and this condition is well known in pre-modern medical texts and documents as a fairly common cause of morbidity. Given these facts, it is surprising that the literature on palaeopathology provides very little evidence of this disease in archaeological human skeletal samples. The medieval sample (N=687) of human remains from Wharram Percy, North Yorkshire, England contains a remarkable subsample of eight burials in which a spectrum of pathological features is expressed. The subsample includes infants ranging in age from 3 to 18 months at the time of death. Ten abnormal bone features were identified in the subsample, including: (i) cranial vault porosity; (ii) orbital roof porosity; (iii) deformation of the mandibular ramus; (iv) deformation of arm bones; (v) deformation of leg bones; (vi) flared costo-chondral ends of ribs; (vii) irregular and porous cortex of the costo-chondral ends of the ribs; (viii) abnormality of the growth plates of long bones; (ix) irregular and porous surfaces of the metaphyseal cortex; (x) thickening of the long bones, particularly in the metaphyseal areas. Not all of these features were found in all of the cases. Nevertheless, the overall pattern of skeletal abnormality fits well with the anatomical and radiological conditions associated with rickets. © 1998 John Wiley & Sons, Ltd.  相似文献   
255.
256.
257.
258.
259.
Perikymata and enamel hypoplasia can be studied most easily by light and scanning electron microscopy of replicas rather than of the original tooth crown surface. Delicate archaeological specimens require special handling. Selection of specimens and cleaning technique are some of the most important factors in producing good replicas, and this paper outlines procedures that have been developed over some years. Several widely available materials produce similarly detailed initial impressions of the crown surface, but an addition-type silicone dental impression material is recommended here because of its superior stability. The replica itself is cast in the mould of the original impression, and a slow-curing low-viscosity Araldite resin-hardener system is recommended. The paper outlines procedures for taking impressions from a variety of dental remains, together with methods for handling, examining and storing the replicas. The non-destructive techniques outlined here make it possible to take records of large numbers of crown surfaces in the field, or during a short museum visit, for later study in the laboratory. Many replicas can be produced from one original crown surface impression and the replicas are very robust—they can be mailed easily to other researchers for records or comparative studies. With continuing calls for reburial or repatriation of archaeological human remains, the production of a permanent record for future study is of considerable concern.  相似文献   
260.
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