Genetic marking shows that Ph+ cells present in autologous transplants of chronic myelogenous leukemia (CML) contribute to relapse after autologous bone marrow in CML

Relapse after autologous bone marrow transplantation for chronic myelogenous leukemia (CML) can be due either to the persistence of leukemia cells in systemic tissues following preparative therapy, or due to the persistence of leukemia cells in the autologous marrow used to restore marrow function after intensive therapy. To help distinguish between these two possible causes of relapse, we used safety-modified retroviruses, which contain the bacterial resistance gene NEO, to mark autologous marrow cells that had been collected from patients early in the phase of hematopoietic recovery after in vivo chemotherapy. The cells were then subjected to ex vivo CD34 selection following collection and 30% of the bone marrow were exposed to a safety-modified virus. This marrow was infused after delivery of systemic therapy, which consisted of total body irradiation (1,020 cGy), cyclophosphamide (120 mg/kg), and VP-16 (750 mg/m2). RT PCR assays specific for the bacterial NEO mRNA, which was coded for by the virus, and the bcr-abl mRNA showed that in two evaluable CML patients transplanted with marked cells, sufficient numbers of leukemia cells remained in the infused marrow to contribute to systemic relapse. In addition, both normal and leukemic cells positive for the retroviral transgenome persisted in the systemic circulation of the patients for at least 280 days posttransplant showing that the infused marrow was responsible for the return of hematopoiesis following the preparative therapy. This observation shows that it is possible to use a replication-incompetent safety-modified retrovirus in order to introduce DNA sequences into the hematopoietic cells of patients undergoing autologous bone marrow transplantation. Moreover, this data suggested that additional fractionation procedures will be necessary to reduce the probability of relapse after bone marrow transplantation in at least the advanced stages of the disease in CML patients undergoing autologous bone marrow transplantation procedures.     

PET／PC共混物的辐射效应研究

研究了经溶液共混制备的聚对苯二甲酸乙二醇酯／聚碳酸酯（ＰＥＴ／ＰＣ）共混物的辐射效应。结果表明：ＰＥＴ／ＰＣ共混物在辐照过程中未发生酯交换反应和交联反应，但有降解反应发生。在研究的剂量范围内，辐照对ＰＥＴ／ＰＣ共混物中ＰＥＴ和ＰＣ的晶体形态影响不明显。     

以YAG为添加剂的气压烧结氮化硅

本文以添加ＹＡＧ的反应烧结氮化硅（ＲＢＳＮ）为前驱体，采用气氛加压烧结的工艺，在０．５～９．０ＭＰａ氮气压力范围，研究了不同氮压对烧结体的密度、相组成、强度和显微结构的影响及其相互间的关系。研究表明，通过改变氮气压力能有效地调控材料的显微结构，材料的性能又受控于显微结构的变化。     

Delay-optimal quorum consensus for distributed systems

Given a set of nodes S, a coterie is a set of pairwise intersecting subsets of S. Each element in a coterie is called a quorum. Mutual exclusion in a distributed system can be achieved if each request is required to gel consensus from a quorum of nodes. This technique of quorum consensus is also used for replicated distributed database systems, and bicoteries and wr-coteries have been defined to capture the requirements of read and write operations in user transactions. The author is interested in finding coteries, bicoteries, and wr-coteries with optimal communication delay. The protocols take into account the network topology. They design delay-optimal quorum consensus protocols for network topologies of trees, rings, and clustered networks     

晶体管的计算机辅助设计

将晶体管设计中繁琐的纵向、横向参数的设计计算以及参数验算,采用Basic人机对话方式,由计算机完成。并用BAsic语言绘制出所需的七块光刻掩膜图。既大大地减轻了设计人员繁琐劳动、缩短了设计时间、提高设计质量,又便于修改。还可广泛用于同种结构的不同动率要求的各种晶体管的设计中。     

双重孔隙介质油藏中的吸渗排油作用

利用美国SSI公司研制的COMPN模拟软件对双重孔隙介质油藏一种重要的开采机理 吸渗排油进行了模拟研究,考察了一个基质岩块为四周裂缝所包围时.在驱动压力和毛管压力的不同平衡(驱动压力和毛管压力的相对大小)关系下的水驱油采收率和水驱油效率的变化规律.     

论滚齿加工在机测量技术

本文论述了滚齿在机测量中一些重要问题．应用偏心误差理论，揭示了以齿轮的齿顶、齿根和内孔为测量基准的测量齿距误差的实质，并对这三种基准进行了对比分析．指出了不同测量基准所测结果不同，若基准选择不当，有时产生“误收”或“误废”．论文针对当前滚齿在机测量装置存在问题．提出了一种滚齿在机１８０°转位双啮综合测量法，测量原理正确，结构简单，易于推广．     

工业CT技术在铸造技术中的应用

介绍了工业ＣＴ在铸件的缺陷探伤，壁厚测量以及铸造工艺控制中的应用。     

混合型表面活性剂液膜法处理含酚废水研究

研究了兰－１１３Ｂ＝Ｓｐａｎ－８０－－煤油ＮａＯＨ液膜体系处理苯酚废水的最佳操作工用于对高浓度含酚废水进行处理，实验结果表明，混合型表面活性剂各项指标均较好，除酚效率可达９９％以上，对内相ＮａＯＨ的最佳浓度的确定给出了估算方法。