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牙周组织老龄化变化及其对正畸牙移动的影响 被引量:1
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作者 易颖煜 赵宁 沈刚 《国际口腔医学杂志》 CAS 2014年第4期492-496,共5页
牙槽骨老龄化变化表现在牙槽嵴高度降低、骨质疏松、骨密度减低,骨吸收大于骨形成。牙周膜老龄化改变体现在胶原纤维增多,牙周膜厚度变薄,牙周膜的反应性改建能力下降。牙龈老龄化变化体现在牙龈上皮角化程度降低,牙龈结缔组织中的细胞... 牙槽骨老龄化变化表现在牙槽嵴高度降低、骨质疏松、骨密度减低,骨吸收大于骨形成。牙周膜老龄化改变体现在胶原纤维增多,牙周膜厚度变薄,牙周膜的反应性改建能力下降。牙龈老龄化变化体现在牙龈上皮角化程度降低,牙龈结缔组织中的细胞数量减少。随着牙槽嵴高度的减少,边缘龈高度也会降低。骨质疏松会加速正畸治疗过程中牙体的移动,不利于正畸移动牙体在新的位置上的重建与稳定。随着患者年龄的增长,正畸治疗会越来越费时间,牙槽骨内幼稚细胞、成骨细胞以及血管数目和骨髓腔减少,骨代谢降低,牙移动缓慢,口周肌改建适应时间延长,牙槽骨的更新、改建能力减弱。老龄化变化使牙周膜细胞活性降低,胶原形成速率减慢,受牵拉侧骨形成和受压侧骨吸收迟缓。在机械力刺激下,牙周膜细胞会反应性地增加地诺前列酮释放到龈沟液中的水平,这可能是成年患者正畸治疗速度缓慢的原因。 展开更多
关键词 牙周组织 老龄化变化 正畸 牙移动
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基于第六次人普数据谈中国人口老龄化新变化 被引量:9
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作者 冯慧阳 《商业文化》 2011年第8X期139-139,共1页
本文在提出人口老龄化的标准后,基于第六次人口普查的主要数据和参照历史的几次人口普查数据,对中国人口老龄化的新变化进行了描述并分析其主要特点,认为中国人口老龄化正在加速,人口老龄化既是挑战,又是机遇,企业应该采取措施积极应对。
关键词 人口老龄化变化 第六次全国人口普查 未富先老
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SPATIAL-TEMPORAL CHANGES AND TRENDS OF AGEING IN CHINA 被引量:1
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作者 WANG Wu-yi ZHANG Li +3 位作者 LI Hai-rong LI Ri-bang YANG Lin-sheng LIAO Yong-feng 《Chinese Geographical Science》 SCIE CSCD 2005年第3期200-205,共6页
This study focuses on the development stages of ageing and its regional differences in China based on examination of official statistics and documents. The development of ageing in China has experienced three major st... This study focuses on the development stages of ageing and its regional differences in China based on examination of official statistics and documents. The development of ageing in China has experienced three major stages. Firstly, in the 1950s, low coefficient of elderly population (over 65 years) paced up to primary adult type. Secondly, there was a deeply drop of the elderly population because of natural disaster and political factors in the 1960s. Thirdly, from the 1970s to the end of 20th century, the constant increasing of elderly coefficient made China close to elderly society. With statistic data of population, Logistic model is used to simulate the future development of ageing, and two characteristics of development of ageing are presented. Firstly, as for ageing from 2005 to 2050, the elderly coefficient will grow up significantly from 8.48% to 16.30%. Secondly, after 2025, the increasing rate of elderly coefficient will slow down gradually. The regional differences of elderly population in China can be summarized as follows: 1) the eastern China possesses higher elderly coefficient and huger elder population than the western China; 2) about 47.4% of municipalities and provinces in the eastern China become elderly especially Shanghai, Zhejiang Province, Jiangsu Province, Beijing, Tianjin and Shandong Province; 3) ageing intensity is higher in rural area than urban area but getting close each other, and there are more elderly people in rural area than in urban area. Therefore, these will arose aged care problems, and it becomes important issue to establish the social security system in rural areas as soon as possible for elderly people. 展开更多
关键词 ageing ageing in rural area China
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