计算机联锁控制系统安全性保障体系的一种模型

根据铁道部１９９４年颁布的《微机联锁系统暂行技术条件》，在阐述可靠性、安全性、故障－安全等概念及其之间关系的基础上，提出了一种计算机联锁控制系统安全性保障体系的描述模型．从这一模型可以清楚地了解到计算机联锁控制系统安全性保障体系的内涵．该模型的提出对计算机联锁控制系统安全性保障的实现奠定了理论基础．     

改进体育系人体解剖学实验课教学之我见

加强体育系实验课教学是高校评估和高校教学改革的一项重要指标人体解剖学实验课教学是其中的一个重要组成部分本文根据淮北煤师院体育系人体解剖学实验室建设与实验课教学现状进行分析，提出促进人体解剖实验课程教学的一些想法     

高校德育工作若干问题的思考

重点讨论了高校德育工作面临的挑战和所需采取的基本对策，其中包括德育队伍建设、观念转变、目标的分解落实、阵地构建．本文首次提出第四课堂的新概念．     

区域地理若干有发展前途的理论

本文首先从区域地理的核心要素景观出发,引伸出“位置”和“地点”两要素,然后初步分析了揭示“位置”和“地点”的四大理论体系以及它们之间的关系。     

Transformation of mononuclear phagocytes in vivo and malignant histiocytosis caused by a novel murine spleen focus-forming virus

The study of retrovirus-induced leukaemias in mice is a powerful tool for the elucidation of the normal regulation of the haematopoietic system. The acute murine spleen focus-forming viruses (SFFV) can be classified according to the haematopoietic lineage on which they exert their effects in the adult mouse. Here we report a new SFFV isolate, the AF-1 virus, with the novel ability to transform cells of the mononuclear phagocyte lineage. The virus was isolated from sarcomas that were induced on passage of a cloned Friend helper virus (F-MuLV, 643/22F) in newborn BALB/c mice. We have cloned the transforming defective subunit of the AF-1 viral complex in NRK cells and isolated several subclones. Analysis of the proviral genome in two non-producer cell clones reveals that AF-1 virus contains Harvey v-ras-specific sequences (Fig. 1). Thus, AF-1 virus is closely related to Harvey murine sarcoma virus (Ha-MSV), and is, at present, the only tool by which permanent cell lines can be obtained from mononuclear phagocytes in the mouse.     

Functional modifications of cytotoxic T-lymphocyte T200 glycoprotein recognized by monoclonal antibodies

Plasma membrane glycoproteins of cytotoxic T lymphocytes (CTLs) are involved in the binding to and subsequent destruction of appropriate target cells. The electrophoretic profile of surface proteins of mature CTLs, particularly those of high relative molecular mass (Mr), is markedly different from that of naive peripheral T cells or non-cytolytic T cells, suggesting the possible involvement of these molecules in the activation of CTLs and/or in the lytic process itself. By generating monoclonal antibodies to cell-surface proteins of CTL clones, we have now detected CTL-specific modifications in one of these high-Mr membrane proteins, T200. Although forms of T200 are found on a wide variety of cell types, the neoantigenic determinants recognized by our antibodies are present exclusively on activated T cells and in high concentrations only on CTLs. Furthermore, the expression of the modifications recognized by our antibodies is influenced by soluble factors and also seems to have functional significance, as monoclonal antibodies specific for these novel epitopes block cytolytic activity.