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151.
Yin-gang Zhang Zheng-ming Sun Jiang-tao Liu Shi-jie Wang Feng-ling Ren Xiong Guo 《浙江大学学报(自然科学英文版)》2009,10(7):522-527
Objective: The age-related change is important part of degenerative disc disease. However, no appropriate animal model or objective evaluation index is available. This study aimed to investigate the features of intervertebral disc degeneration in aging process of rats. Methods: 22-month-old Sprague-Dawley (SD) rats were used as spontaneously occurring intervertebral disc degeneration models and 6-month-old rats as young controls. Expression of collagen types II and X was measured by immunohistochemistry. Degenerations of intervertebral discs were scored according to Miyamoto’s method. Numbers and areas of afferent vascular buds were measured. The thicknesses of non-calcified and calcified layers were measured and statistically analyzed. Results: There were less collagen type II expression and more collagen type X expression in the calcified layer of the cartilage endplates and nucleus pulposus in the rats of the aged group than in the young control. There were fewer and smaller afferent vascular buds in the rats of the aged group than in the young control group. The ratio of the non-calcified to the calcified layers in the rats of the aged group significantly decreased, compared with that of the young control group (P<0.01). Conclusion: Rats can spontaneously establish intervertebral disc age-related degeneration. The expression of collagen types II and X, numbers and areas of afferent vascular buds, the ratio of the non-calcified to the calcified layers, and water and glycosaminoglycan contents in the nucleus pulposus are sensitive indexes of intervertebral disc degeneration. 相似文献
152.
马克思认为,生产力的发展与人的发展是社会进步的评价尺度。这两种尺度同时也是我国社会主义现代化建设的价值取向。社会主义现代化建设,既是生产力发展的过程,也是人的全面发展的过程。邓小平继承和发展了这一思想,把发展生产力作为社会主义的根本任务,把人的全面发展作为社会主义建设的最终目的,并通过改革开放这一根本途径来促进生产力发展和人的发展。 相似文献
153.
154.
Joint Funds of National Natural Science Foundation of China(NSFC) are initiated by different stakeholders,which aim to play a better guiding role to support basic research in specific areas and directions.They have formed an important part of the national natural science funding system,which is responsible for advancing science and technology in an expanding frontier.The article would briefly summarize the joint funds strategic goals,programs implementation and achievements in the past decade, and provide a perspective on their future development. 相似文献
155.
156.
就山东一境而言,泰山崇拜和碧霞元君信仰在海岱之间自西向东传布。据目前所掌握的资料,泰山信仰传布的力度从明代至清前期渐趋增长,而自光绪末年至民国却是一个转折。本文选定青山碧霞宫与大泽山日照庵两座庙宇作为研究中心,来探讨泰山信仰清末民初在泰山到滨海一线的传布情况。泰山信仰在海岱之间传布过程中,受到空间距离、地域文化等客观因素的制约,呈涟漪状,以泰山为中心,越趋向边缘(边远)地区,影响力越弱;即使有稳定文化内核的碧霞元君信仰,也经受了诸多损益,多种神灵品格层累而至于在青山庙宇出现相互矛盾的几个碧霞元君,在大泽山也经历了从碧霞元君到无生老母的主神转变。 相似文献
157.
文章对影响永济市小麦、玉米的产量进行分析,并提出本市小麦-玉米的"两晚"栽培技术,在不增加投资的情况下,可提高粮食产量,增加农民收入. 相似文献
158.
We present a novel and simple design of an air-slot mode-gap photonic crystal(PC) nanocavity by introducing a linear air slot to the center of a line-defect waveguide in a two dimensional triangular-lattice silicon PC slab.A high quality factor(Q factor) of 8.42*105 and an ultrasmall mode volume of 0.998 cubic wavelength are achieved in an optimized air-slot nanocavity which is a suitable choice for the strong matter-field interaction in free space.The high Q cavities with ultrasmall mode volume are important for applications such as quantum computation and nonlinear optics. 相似文献
159.
在知识经济时代,人才是生产力中最活跃的因素,企业竞争归根到底是人才的竞争.因此选择并且留住高素质的人才,是企业生存发展的前提. 相似文献
160.
Utilizing OnLine Short Text (OLST) in social networking tools such as microblogs, instant messaging platforms, and short message service via smart phones has become a routine in daily life. OLST is appealing for personal covert communication because it can hide information in a very short carrier text, and this concealment is hard to detect due to the diversity of normal traffic. However, designing appropriate schemes confronts several challenges: they need to be provably secure, and their performance needs to maintain high efficiency and handy usability due to the short length of OLST messages. In this paper, we propose a family of customized schemes known as HiMix, HiCod, HiOpt, and HiPhs for text steganography in OLST. These schemes are evaluated in terms of their security and their performance with regard to two metrics that address the particular characteristics of OLST: hiding rate and hiding ease. All proposed schemes are proved to be at least computationally secure, and their performance in terms of hiding rate and hiding ease justifies their applicability in social networking tools that utilize OLST. 相似文献