Induction of formation of presynaptic terminals in neuroblastoma cells by synapsin IIb

The synapsins are a family of closely related phosphoproteins (termed synapsins Ia, Ib, IIa and IIb) associated with synaptic vesicles and implicated in the short-term regulation of neurotransmitter release from nerve endings. During development, expression of the synapsins correlates temporally with synapse formation, but there has been no direct evidence that they are involved in synaptogenesis. Here we report that overexpression of synapsin IIb in the neuroblastoma x glioma hybrid clonal cell line NG108-15 leads, during cell differentiation, to marked increases in the number of neuritic varicosities and in the numbers of small clear vesicles and large dense core vesicles per varicosity, as well as to the appearance of synapse-like cell-cell contacts. Thus, synapsin IIb may be involved in the regulation of synapse formation and, as a result, in long-term neuronal signalling.     

县城搬迁项目管理系统研究

根据县城搬迁项目的特点,从项目的安排、合理性判断以及投资变动决策方法3方面入手,建立了切合实际的数学模型,并给出具体的县级项目管理系统的数学模型和应用实例.     

流化床埋管表面局部空隙率测试装置的研制

1 基本原理对于换热表面附近的气固两相运动情况,即使采用内窥镜、光导纤维、X射线等先进技术,也仅能定性地观察气固两相运动情况.为了进一步研究床内埋设表面的换热机理,了解表面附近气固两相运动情况,本文研制了能从一定程度上反映气固两相运动的换热表面局部瞬态空隙率的测量装置.在流化床内埋设换热表面上嵌入两个电容极片,换热表面附近气体和固体颗粒则是电容器的电介质.任意两个相隔一定距离的导体都可以构成一个电容器.在导体的几何形状与位置确定后,其电容量只与其周围电介质的介电常数ε_e有关,即     

A study on the pharmacokinetics in mouse of adenine-9-beta-D-arabinofuranoside 5-monophosphate conjugated with lactosaminated albumin

In plasma of mice injected with adenine-9-beta-D-arabinofuranoside monophosphate (ara-AMP) coupled to human lactosaminated serum albumin (L-HSA) some of the ara-AMP molecules are enzymatically released, whereas others remain linked to L-HSA. Evidence has been obtained that ara-AMP is not deaminated when it is conjugated to L-HSA, in contrast to the free drug which is rapidly metabolized to its hypoxanthine derivative.     

分光光度法测定江、河水中木质素

本文采用磷钨酸钠为显色剂,在氢氧化钠介质中用分光光度法测定水中微量木质素。方法快速、准确。线性范围0.5—6ppm,回收率在90%以上。适于江、河水中木质素分析。     

A combination of a particular HLA-DP beta allele and an HLA-DQ heterodimer confers susceptibility to coeliac disease

Coeliac disease is an autoimmune disease of the intestinal mucosa, elicited by ingestion of wheat gluten in genetically susceptible individuals. Susceptibility to coeliac disease has been associated with the serologically defined variants DR3 and DR7 of the class II antigens encoded by the HLA-D region. Three related class II antigens, each consisting of an alpha and a beta glycoprotein chain, have been identified and are designated HLA-DR, HLA-DQ, and HLA-DP. These highly polymorphic transmembrane proteins bind peptides derived from the processing of foreign antigens and present them to T lymphocytes; they also influence the specificity of the mature T-cell repertoire. The role of HLA-DP polymorphism in susceptibility has not been as fully explored as that of the other class II antigens because of the complexity of the primed lymphocyte typing (PLT) method for determining DPw specificities. Here we use a new DNA-based method of HLA-DP typing to analyse the distribution of DP beta alleles in a group of coeliac disease patients and healthy controls. Two specific DP beta alleles (DPB4.2 and DPB3) are increased in the patient population. Comparison of the DP beta sequences suggests that the polymorphic residues at position 69 and at 56 and 57 may be critical in conferring susceptibility. Further, the contribution of the susceptible DP beta alleles appears to be independent of linkage to the previously reported DR3 and DR7 markers for coeliac disease. The distribution of DQ alpha and beta alleles in patients suggests that a specific DQ heterodimer may be responsible for the observed DR associations. Individuals with both this DQ antigen and a specific DP beta allele are at increased risk for coeliac disease.     

对高分子材料摩擦磨损机理的考察研究

本文综合论述了美国维吉尼亚州立大学机械系 N.S.Eiss 教授对高分子材料摩擦学特性的研究和应用情况。考察研究表明,该项研究已取得了许多成果,在美国处于领先地位。研究结果证明了高分子材料的摩擦学特性取决于分子结构、分子量、结晶度、横向环的密度、分子定向、薄膜转移、表面粗糙度及温度等因素。     

思想政治教育过程中"双主体"的运行机制

文章着重论述了“双主体”在思想政治教育过程中的运行机制,即“三次转化”与“两次飞跃”,最后阐述了“双主体”的运行特点。     

论海德格尔对现代技术世界的超越

从海德格尔对艺术作品的分析中寻找一种超越单纯的技术视角的方法来克服技术产生的弊病。     

Iron acquisition and virulence in the motile aeromonads: siderophore-dependent and -independent systems

During an infection, a microbial pathogen must acquire all of its iron from the host. Aeromonas isolated producing the siderophore amonabactin obtain iron either from host Fe-transferrin (siderophore dependent) or from host heme-containing molecules (siderophore independent). Isolates producing the siderophore enterobactin do not utilize Fe-transferrin in serum and probably rely exclusively on host heme iron.