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311.
Astronauts and experimental animals in space develop the anemia of space flight, but the underlying mechanisms are still unclear. In this study, the impact of simulated microgravity on proliferation, cell death, cell cycle progress and cytoskeleton of erythroid progenitor-like K562 leukemia cells was observed. K562 cells were cultured in NASA Rotary Cell Culture System (RCCS) that was used to simulate microgravity (at 15 rpm). After culture for 24 h, 48 h, 72 h, and 96 h, the cell densities cultured in RCCS were only 55.5%, 54.3%, 67.2% and 66.4% of the flask-cultured control cells, respectively. The percentages of trypan blue-stained dead cells and the percentages of apoptotic cells demonstrated no difference between RCCS-cultured cells and flask-cultured cells at every time points (from 12 h to 96 h). Compared with flask-cultured cells, RCCS culture induced an accumulation of cell number at S phase concomitant with a decrease at G0/G1 and G2/M phases at 12 h. But 12 h later (from 24 h to 60 h), the distribution of cell cycle phases in RCCS-cultured cells became no difference compared to flask-cultured cells. Consistent with the changes of cell cycle distribution, the levels of intercellular cyclins in RCCS-cultured cells changed at 12 h, including a decrease in cyclin A, and the increasing in cyclin B, D1 and E, and then (from 24 h to 36 h) began to restore to control levels. After RCCS culture for 12–36 h, the microfilaments showed uneven and clustered distribution, and the microtubules were highly disorganized. These results indicated that RCCS-simulated microgravity could induce a transient inhibition of proliferation, but not result in apoptosis, which could involve in the development of space flight anemia. K562 cells could be a useful model to research the effects of microgravity on differentiation and proliferation of hematopoietic cells.  相似文献   
312.
诚信是中华民族的传统美德,是社会生活正常运行的道德基础,是市场经济有序发展的基本要素,是和谐社会构建的重要标尺。但近年来,在大学生无视诚信的现象不容忽视。为此要发扬传统文化之精髓,弘扬当代大学生的诚信精神,并且实行知行统一。  相似文献   
313.
Dating back to the Apollo and Skylab missions, it has been reported that astronauts suffered from bacterial and viral infections during space flight or after returning to Earth. Blood analyses revealed strongly reduced capability of human lymphocytes to become active upon mitogenic stimulation. Since then, a large number of in vitro studies on human immune cells have been conducted in space, in parabolic flights, and in ground-based facilities. It became obvious that microgravity affects cell morphology and important cellular functions. Observed changes include cell proliferation, the cytoskeleton, signal transduction and gene expression. This review gives an overview of the current knowledge of T cell regulation under altered gravity conditions obtained by in vitro studies with special emphasis on the cell culture conditions used. We propose that future in vitro experiments should follow rigorous standardized cell culture conditions, which allows better comparison of the results obtained in different flight- and ground-based experiment platforms.  相似文献   
314.
In order to justify high expenditure during this period of financial crisis, Space Agencies have attempted to increase the returns on their investments in Space missions by encouraging the commercial use of advanced technologies. The development of a technology transfer process from Space to Earth not only benefits the Aerospace industry but also the network of national companies. Technology transfer has been shown to stimulate innovation in business and commerce, support economic growth and provide a return on public investment in research and development (R&D). The aim of this paper is to systematically review the Space technology transfer literature and to suggest directions for future research. The range of research and studies in the literature on this topic requires a systematic review to summarize the results in an unbiased and balanced manner and to interpret these in a way that highlights the research gaps. This article presents an overview of the dominant thinking (explicit in selected articles from 1995 to present), indicating the problems of analysis, research gaps and a future research program.  相似文献   
315.
扼要介绍了南京航空航天大学图书馆最近几年在建设电子化、网络化基础设施,建立电子文献资源,配套相应服务等方面所作的努力。  相似文献   
316.
德国染料工业发展的历史证明,高校的科技产业只有依据持续的技术创新,才能不断地发展壮大。当前要借助股份制的改造理顺高校与科技产业之间的产权关系并获得充分的金融保障。高校的科技产业应当在高技术领域选择突破口,进行不断的技术创新,这在我国将有广阔的发展前景。  相似文献   
317.
社区图书馆是一种特殊类型的基层图书馆,它对廊坊市的文化事业繁荣起着重要作用。本文结合欧美国家社区图书馆的创办和管理经验,并结合廊坊的实际情况以及文化强国的策略,提出创办面向老人和青少年的特色社区图书馆,为市民打造一个科学文化知识普及和信息交流传播的平台,从而推动廊坊文化的繁荣与和谐。  相似文献   
318.
随着我国金融行业的全面开放和发展,金融行业的竞筝越来越激烈,品牌已经成为金融企业获取长期竞争优势的重要来源。在服务品牌资产模型的基础上,结合金融行业自身的特点,构建金融品牌资产模型。通过从金融企业服务营销努力,到金融品牌知识建立,再到金融品牌关系形成,最后到金融品牌市场表现四个阶段来创建金融品牌资产。最后还提出了运用模型创建金融品牌资产的方法要点。  相似文献   
319.
一篇短短八十一字的《陋室铭》,竞流传了一千二百多年,成了千古绝唱。那是因为在《陋室铭》中,我们可以看到中国历史文化的精髓,可以看到人生应该怎样度过;在人生的逆境时应该怎样去面对。不仅如此,从《陋室铭》的创作中,我们还可以理解经典的地域(朗州)文化是怎样成为中华历史文化大家庭中的一员的,以至每次读《陋室铭》都有一份别样的清新,都有一份格外的心动与奋进,都能为读者心灵种下茁壮的生命之源。在《陋室铭》里可以看到朗州(常德)文化的璀璨,在中国历史文化中闪耀的光芒。  相似文献   
320.
随着社会经济的发展,人类社会面临着越来越严重的环境污染与资源匮乏问题。为了实现人类社会的可持续发展,必须重视并大力发展静脉产业。我国城市静脉产业经过几年的发展,已经取得了一定的成绩,但仍存在着诸多问题,必须有针对性的加以解决,为其长远目标的实现提供保障。  相似文献   
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