Effect of temperature on in vitro proliferative activity of human umbilical vein endothelial cells

Human umbilical vein endothelial cells, skin fibroblasts, and retinal pigment epithelial cells are cultivated in medium supplemented with 15 to 20% serum in our laboratory. The effects of various incubation temperatures on the proliferation of these cells was examined. Our study shows that the mitogenic response of the endothelial cells to a change of temperature differed markedly from that of the fibroblasts and epithelial cells. Cultivation of human umbilical vein endothelial at 37°C required seeding densities as high as 1–2×10⁴ cells/cm², and yet resulted in a low growth rate and premature senescence. However, under the same culture conditions, but at 33°C, the proliferative capacity of these endothelial cells was potentiated. The results were striking; at 33°C the cells grew actively and the life span was extended. The number of cumulative population doublings increased fourfold compared with that for the same cells cultivated at 37°C. The inoculum size could be reduced, since at 33°C the endothelial cells were able to replicate at seeding densities as low as 20 cells/cm². The cells serially subcultured at 33°C retained morphological features and specific immunological markers of endothelial cells.     

基于资源回收的容错最早时限优先调度

基于时间冗余的实时容错调度算法 ,可调度条件以任务的最坏执行时间和为任务预留容错操作的时间为分析基础 ,任务拒绝率高 ,系统资源利用率低。提出了基于资源回收的容错最早时限优先调度 ,以容错实时调度算法FT_EDF为基础 ,利用任务的实际执行时间往往低于最坏执行时间的特性 ,收集已完成任务释放的资源供等待任务使用 ,在保证系统容错要求的同时 ,提高了任务吞吐量和系统资源利用率。     

新形势下企业人力资源开发与管理

新形势下企业人力资源开发和管理是一个典型的系统工程问题，其中势必要涉及管理系统科学的近期发展和社会经济系统的总体趋势。企业能否在系统的结构和功能面前适应人力资源开发与管理的新要求则是系统工程研究课题的业务之急。为此，本文就这一论题作一次肤浅的系统论述。     

VLDL substrate properties and efficiency of their metabolic transformation by LPL

Summary A study was made of the regulation of the triglyceride hydrolysis catalysed by LPL from bovine milk, by the apoproteins from human plasma VLDL. Both isolated apolipoproteins, and those found on the surface of plasma VLDL particles, were investigated. A concentration-dependent activating action of apo C-II on the hydrolysis of emulsified triolein, and uncompetitive inhibition of VLDL triglyceride hydrolysis by apo C-III were found. It is suggested that VLDL lipolysis might be controlled in vivo trough the variation of the relative surface content of these enzymatic activity modulators.     

环境地貌学几个问题的探讨

本文探讨了环境地貌学的概念、性质、产生背景、学科体系和服务内容等。     

Anti-bovineβ-lactoglobulin antibodies react with a human lactoferrin fragment and bovineβ-lactoglobulin present in human milk

Human milk samples react against anti-bovine-lactoglobulin rabbit antibodies, as measured by a competitive radioimmunoassay. Immunoreactivity was positive even in milk from mothers consuming a diet free of cow's milk. An increase with a diet rich in cow's milk proteins was detected by immunoelectrophoresis. The human milk fraction cross-reacting with anti-bovine-lactoglobulin antibodies corresponds to the 20 kDa fragment from the N-terminal end of human lactoferrin. Three regions of this fragment exhibit sequence homology with a sequence contained in cow's-lactoglobulin (between residues 124 and 141).     

人尿胰蛋白酶抑制剂的分离纯化

人尿经吸附剂处理，硫酸铵沉淀后，得到胰蛋白酶抑制剂粗品。粗品经ＤＥＡＥ－ＳｅｐｈａｄｅｘＡ－５０层析及ｔｒｙｐｓｉｎ－Ｓｅｐｈａｒｏｓｅ亲和层析，得到两种ＨＵＴＩ：ＨＵＴＩ１与ＨＵＴＩ２。ＨＵＴＩ１的比活为３５５６ｕｎｉｔｓ／ｍｇ，活性回收率为３５％，含分子量６７０００与２５０００两种组粉；ＨＵＴＩ２的比活为３３８５ｕｎｉｓ／ｍｓ，活性回收率为３１％，分子量为６７０００。经二步层析纯化，纯化因子达     

人体受振时生理信号变化趋势研究

通过试验研究全身振动对人体生理参数的影响，尝试用工程信号分析处理技术来处理人体的生理信号，结果表明用这种方法进行人体受振的生理量评价方法的研究是切实可行。     

运输方式互利共生的非线性动力学模型

综合运输结构决定综合运输系统的功能，各种运输方式之间的竞争和协作影响综合运输的结构。因此，研究各种运输方式的相互作用机制就显得很重要。本文通过对各种运输方式互利共生机制的研究，展示了各种运输方式协作互利的前景。仿真结果表明，如果各种运输方式的相对资源优势比较明显，就存在互利共生的可能性，并存在一个最优的合作水平。较高的资源转换效率和资源使用效率能使互利共生机制得到更充分的体现。与非合作动态博弈情况相比，协作情况下互利共生机制能发挥更大的作用。因此，通过政府部门等外力建立协作的机制，是更好地实现互利共生机制的必要前提。     

财政政策促进中国内生经济增长的经验分析

增加人力资本积累、加快技术自主创新、促进内生经济增长是中国创造新的比较优势、实现跨越式发展的重大机遇。综合研究表明,财政用于人力资本和技术进步的投资有利于鼓励“内生化”知识积累和技术进步，实现经济长期持续增长。应制定相应财政政策，增加人力资本投资，促进技术进步。保护和激励创新，从而为中国经济保持持续稳定快速增长的良好势头找到一个新的支撑点。