排序方式: 共有92条查询结果,搜索用时 15 毫秒
1.
2.
《International Journal of Osteoarchaeology》2017,27(5):828-838
One of the main factors involved in entheseal changes (EC) aetiology may be related to the physiological limits of biomechanical loading fixed during bone development, such that higher load during childhood and the adolescent growth spurt leads to a lower frequency of EC during adulthood. In this sense, it is possible that ECs may be related to overloading beyond an individual's normal physiological limits as established during childhood and adolescence. This meta‐analysis tested this aetiological possibility by studying the influence of terrain on the entheses of the lower extremities. The hypothesis is that individuals who inhabited rugged terrain have lower EC than those living in flat terrain. This is because biomechanical loads associated with rugged terrain will lead to a higher normal capacity (defined during skeletal development) mitigating the probability of overloading compared to those living in flat terrain who will therefore have a higher frequency of ECs. To test this, papers reporting EC frequencies in the lower limbs were analysed alongside the local terrain. Terrain was defined into two categories: flat or rugged based on altimetry profile, i.e. the average elevation gains and losses along four specific paths (North‐South, East‐West, Northwest‐Southeast, Southwest‐Northeast). Odds ratios were calculated to compare rugged and flat terrain. The overall results are consistent with the hypothesis that overloading is a factor in EC aetiology. However, when the analysis is conducted by sex and side, this general trend does not always occur. Limitations such as the lack of standardized age ranges could be affecting the outcome, i.e. older individuals have a higher frequency of ECs. The findings of this analysis suggest that the theoretical assumptions associated with the cause of ECs require further testing and evaluation. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
3.
Yang Jiao 《Frontiers of History in China》2020,15(2):292
This article studies the relationship between local society and social change in rural north China from the late Qing dynasty to the People’s Republic of China period through the activity of “Zhuo huanggui” (literally, “Catching the Yellow Ghost”). “Catching the Yellow Ghost” is a ritual activity in Guyi village, Wu’an county, Hebei province. According to villagers there, “Catching the Yellow Ghost” has been celebrated since the late Qing dynasty. However, due to political pressures in the 1950s, it was not until the 1980s that “Catching the Yellow Ghost” began to be revitalized. Since that time, “Catching the Yellow Ghost” has gained rapid popularity and fame in north China. Through the lens of the “Catching the Yellow Ghost” ritual, this article explores social transformation in China from the late 19th to the early 21st century. By analyzing the continuity and discontinuity of “Catching the Yellow Ghost,” this article offers a new understanding of the relationship between local society and social change in rural north China. 相似文献
4.
日本经济的长期萧条有着深刻的制度原因,本文对经济管理模式、科技创新制度、土地使用制度、企业所有关系、主银行制度和劳动雇佣关系等六个方面的制度进行分析并提出这六方面的制度变迁建议,最后指出人的因素是导致制度变迁长期性和反复性的重要原因。 相似文献
5.
青海近代的农业垦殖与环境变迁(1840~1949) 总被引:3,自引:0,他引:3
近代是历史时期波及青海全省范围的大规模农业垦殖的起始阶段,从其发展历程来看可以分为衰落、恢复并快速发展和再度衰落三个时期。不同时期,人口数量、农垦的地域分布和水利事业发展均有所不同。近代农垦对青海环境变迁所造成的影响依然是局部的。 相似文献
6.
7.
自然环境变迁与十六国政权割据局面的出现 总被引:7,自引:0,他引:7
中国古代历史发展的自然环境及自然环境变迁对历史进程的影响,起一个具有重大理论和现实意义的问题。东汉末年以来自然环境变迁是西晋灭亡和十六国割据局面形成的重要原因。由于全球性寒冷干燥期的出现,我国北方沙漠面积不断扩展,各游牧民族原有的生存环境不断恶化,于是纷纷南迁,起着西晋统治集团内乱之际,夺取了政权。 相似文献
8.
建国初期的社会变迁与党对思想文化的整合 总被引:2,自引:0,他引:2
1949~1956年中国经历了急速的社会经济政治变迁。为了解决由此变迁带来的种种思想文化问题,保证中国先进文化的前进方向,党对思想文化进行了有力的整合。通过这种整合,确立了马克思主义在思想文化领域的主导地位,丰富了中国社会变迁的历史内涵。 相似文献
9.
个旧锡业开发与生态环境变迁(1890-1949) 总被引:2,自引:0,他引:2
谭刚 《中国历史地理论丛》2010,25(1)
随着1889年蒙自的开关,尤其是1910年滇越铁路的全线通车,极大地改善了云南的对外交通运输条件,推动了个旧锡业的迅速发展。在1890年至1949年的60年间,个旧共生产大锡323042吨,个旧锡业也取代铜业成为近代云南的矿业支柱。个旧锡业在推动云南矿业发展的同时,也对个旧及周边地区生态环境产生了巨大的影响。在1890年至1949年的60年间,个旧地区仅土法炼锡就至少消耗45万吨以上木炭。个旧、蒙自、建水、开远和石屏五县地区天然林平均覆盖率从清初的90%锐减至1940年的2.98%,近三百年间减少了80%以上,个旧锡业开发显然是五县天然林平均覆盖率急剧减少的重要原因。同时,锡矿的大量粗放开采和冶炼,也污染了个旧地区的土壤、水源和空气环境,带来了环境污染问题,影响了当地民众尤其是矿工的身体健康。因此,锡业开发是导致近代个旧及周边地区生态环境变迁的重要原因。 相似文献
10.
水对城市发展至关重要,严重水灾可能会酿成"城毁人亡"的悲局。历史上徐州饱受水灾之苦,特别是黄河决口南徙打乱了原本水系,使得境内水灾频仍,经济和社会发展受阻,在很大程度上导致了城市的衰落。但另一方面,沂、沭、泗以及故黄河所带来的便利灌溉条件则促进了境内古代农业生产;而运河开凿又使徐州处于全国重要的水运枢纽位置,因此带来商贸繁荣、工业发展、人口集聚和城市兴盛。本文在对历史上徐州水系变迁、尤其是水灾频发及其产生原因作出深入分析的基础上,着重探讨了境内水环境变化对徐州城市兴衰主要方面的影响。研究表明:①黄河对徐州水系变迁和城市兴衰影响巨大,直接时间持续近700年;②良好的水环境对历史上徐州境内工农业生产、商品贸易和城市建设起到了极大的推动作用,城市的繁荣兴旺与农田水利的风调雨顺、水上运输的川流不息往往处于同一个时期;③建国后徐州境内水系得到逐步治理与恢复,特别是20世纪80年代中期京杭运河(徐州段)实现全年通航后,其城市发展的水环境得到极大改善,为打造山水生态园林城市提供了良好条件。 相似文献