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   15篇
  免费   0篇
  2017年   2篇
  2016年   1篇
  2015年   2篇
  2013年   1篇
  2008年   1篇
  2007年   1篇
  2006年   1篇
  2003年   1篇
  2002年   1篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1995年   1篇
排序方式: 共有15条查询结果,搜索用时 46 毫秒
1.
The femur remains an important bone in palaeoanthropology and this paper reports various analyses of measurements taken from long-cassette radiographs of adult femurs of a reference population from the south of England (n=81, males 33, females 48). Discriminant analysis confirmed that the male femur is usually larger than the female femur, and that a femur may be sexed with some confidence. Discriminant scores have been derived to permit estimates to be made, from the whole or a part of a femur, of the probability of the male gender. Outcomes from a principal component analysis suggest: that the female proximal femur is a morphological unit; that neck length and shaft length are dissociated and there is no common factor representing linearity; and that the male bicondylar width is anomalous, a finding that is confirmed by other analyses. An estimate of the robusticity of the complete female, but not male, bone may sometimes be made from a proximal fragment. The robusticity of the complete bone may be made confidently from the shaft for both genders. The two width variables relating to a distal fragment cannot be used to predict the robusticity of the complete bone for either gender. A method of defining the position of the waist in terms of displacement in deciles down the shaft is described. The position of the waist seems to have a bimodal distribution. The positive association between age and distal displacement may be due to remoulding of the shaft with age or to a cohort (generational) effect. There is a weak correlation between a small neck–shaft angle and the distal displacement of the waist, two archaic phenotypic traits. Ten statements in the literature relating to the femur have been examined and tested; six are confirmed and four are unconfirmed, and it is suggested that there is a need for further studies relating to the morphology of the femur.  相似文献   
2.
This study examines possible morphological variation in the knee joint of Homo sapiens with increasing age in ostensively healthy and non‐pathological distal femora and proximal tibiae. Throughout the lifetime of each individual, the hard tissue of the knee undergoes considerable remodelling as a response to biomechanical stresses, changes in bone microarchitecture and reduction of bone mineral content as a concomitant of ageing. The knee is also subject to greater levels of degenerative joint disease than any other joint. If death occurs whilst such diseases are in the earliest stages, initial bone changes may not be visually obvious in museum specimens. If such specimens are used for comparative analyses, it is hypothesised that changes might render it problematic if all ages are conglomerated into discrete samples. This study therefore investigates the degree to which the distal femur and proximal tibia change shape during ageing and, if changes are present, whether they are expressed similarly in males and females. It also examines whether changes are of greater magnitude than those morphological differences which might exist between populations. In an example population of African‐Americans, results indicate that there is a statistically significant difference in shape between age groups and those differences become progressively greater between the youngest and oldest adults. Results also show that although morphological variation caused by ageing is apparent, those shape differences attributable to sexual dimorphism are more powerful. When two additional populations are analysed jointly with the African‐Americans (Caucasian Americans and the European Spitalfields sample), results indicate that inter‐population shape differences are considerably greater than differences caused by increasing age. Results imply that it is justifiable to combine specimens of all ages into discrete samples for comparative purposes. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
3.
Age-dependent bone loss in femurs in a medieval skeletal assemblage from Wharram Percy, England was studied. Dual energy X-ray absorptiometry (DXA) was used to measure bone mineral density (BMD) in the proximal femur; radiogrammetry was used to measure cortical index (FEMCI) at the femur mid-shaft. Age-related loss of BMD was found in the proximal femur in both sexes. Females but not males showed loss of FEMCI. Patterning in bone loss with respect to age, sex and site in the skeleton resembled that seen in recent subjects. In this respect the results are similar to those of a previous study of metacarpal cortical bone in the same archaeological assemblage. Given the large difference in lifestyles, and that lifestyle factors are widely held to influence the severity of bone loss in osteoporosis, the similarities between the medieval and modern populations in the patterns of bone loss are surprising. These findings support those from an earlier study of these skeletons in calling into question the role of lifestyle factors in influencing the severity of bone loss in osteoporosis. © 1998 John Wiley & Sons, Ltd.  相似文献   
4.
5.
Two juvenile skeletons excavated from medieval Norwich each have a well‐defined cystic cavitation. One involves the distal femur and the other the proximal tibia. The dry bone and radiographic appearance, as well as the location and age of the individuals, support a diagnosis of metaphyseal cortical defects. Although well‐known in clinical practice, especially in children, this appears to be the first published evidence for the condition in British archaeological material. No other anomalies were detected on the two skeletons. However, the occurrence of two cases in the same cemetery raises the possibility of a genetic influence in the condition. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
6.
The Mid Upper Paleolithic Sunghir 3 late juvenile early modern human, from the most elaborate burial in the Pleistocene, had pathologically foreshortened and anteriorly bowed femora and, based on her dental enamel hypoplasias and transverse lines, sustained severe and persistent systemic stress throughout her decade of life. Her modest femoral and tibial asymmetry and her femoral bicondylar angles indicate non‐pathological patterns of posture and locomotion. The levels of rigidity for her weight‐bearing tibiae and the non‐dominant left arm reflect normal weight‐bearing and manipulation. These indicators are combined with an elevated level of right humeral strength, leading to pronounced humeral diaphyseal asymmetry, combined with elevated muscular insertion asymmetry. In combination with marked upper limb muscle markings and normal levels of bone formation, these reflections of her robustness indicate that she was fully mobile and participated actively in the tasks of her social group. There is no indication of the skeletal hypotrophy/atrophy that would be associated with less than full participation in the mobility and subsistence of her social group. As such, Sunghir 3 joins a growing list of developmentally or degeneratively pathological Late Pleistocene humans who nonetheless remained mobile and active. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
7.
8.
Ni Yunan & Cooper, R. A., 1994:03:28. The graptolite Glossograptus Emmons and its proximal structure. Alcheringa 18, 161–167. ISSN 0311-5518.

New specimens of Glossograptus acanthus from the Ningkuo Shale of China, preserved in relief, help to resolve the much debated problem of the structure of Glossograptus. A model for the proximal structure of the genus is proposed, based on the new material and on Finney's (1978) Athens Shale specimens. The model confirms that Glossograptus has homologous structure and development with Pseudisograptus, and isograptid development type is primitive for the group containing both genera. A cladogram is presented in which the suborder Glossograptina Jaanusson (with families Glossograptidae and Cryptograptidae) together with family Corynoididae Bulman are subsumed within a redefined family Glossograptidae.  相似文献   
9.
10.
Anatomical textbooks describe the lesser trochanter in contemporary humans as being oriented posteromedially. In contrast, orientation of the lesser trochanter towards posterior was observed in some human femora from the Upper Palaeolithic, including the femur of a young adult individual from Germany (Irlich 1), radiocarbon dated to 12 500–11 200 bp (calibrated AMS age). The present study analysed the orientation of the lesser trochanter in femora originating from an early medieval skeletal assemblage (Greding, Germany) and compared the results with those for the Irlich 1 femur. Eleven landmarks, four on the proximal femur, four on the mid‐shaft and three on the distal femur, were recorded with a MicroScribe® digitizer and analysed using AutoCAD® 2010 software. Seven angles and five distances were measured. In the Greding femora, significant differences (p  < 0.05) between sexes were found for several linear measurements, while no significant sex‐related differences existed for angular measurements. For some angular variables related to the orientation of the lesser trochanter, the values for the Irlich 1 femur lay outside the range of variation of the Greding specimens, reflecting the more posterior orientation of the lesser trochanter in the Irlich 1 femur. This posterior orientation of the lesser trochanter was not associated with a particularly low degree of femoral anteversion. It is hypothesised that the differences in orientation of the lesser trochanter between the Irlich 1 femur (and other femora of Upper Palaeolithic individuals) and the femora from Greding could basically reflect differences in traction exercised by the iliopsoas muscle during infancy and childhood between the sedentary agricultural population from Greding and Upper Palaeolithic hunter‐gatherers with a mobile lifestyle. Copyright © 2017 John Wiley & Sons, Ltd.  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