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81.
Monoclonal antibodies against human myelomonocytic cells: detection of certain lineage-specific antigens on CFU-GM progenitor cells 总被引:1,自引:0,他引:1
A series of monoclonal antibodies (mAb) were raised against nonlymphoid leukemic cell lines. Three of them have been characterized in detail. mAb H8 (IgG2), mAB U2 (IgG1), and mAb ML143 (IgM) were established with HEL, an erythroleukemia cell line, U937, a monocytoid (histiocytic) line, and ML-1, a myeloid cell line as immunogen, respectively. A 65 to 75 KD polypeptide was precipitated from monocytes by mAb H8, a 160 KD protein from monocytes by mAb U2, and two broad bands in the regions of 150 and 195 KD from granulocytes by mAb ML143. All three mAb stained peripheral blood monocytes and granulocytes, but not lymphocytes, platelets, and erythrocytes. The mAb reacted with immature myeloid cells in bone marrow, ranging from myeloblasts to mature myelomonocytic cells. They also were reactive with various nonlymphoid cell lines and leukemia of myelomonocytic origin. They did not react with B cell lines and B cell CLL cells. By complement-mediated cytolysis and/or an immune rosette method, antigens H8 and U2 were found to be expressed on the vast majority of CFU-GM (14 days) progenitors but not on BFU-E. Antigen ML143 was not expressed by either progenitor. Furthermore, ML143 antigen was found on T leukemia cell lines, a subpopulation of mitogen-activated T cells, and certain non-T/non-B ALL cells. This reactivity was not found with mAb H8 and U2. The relationship between these mAb and those reported are discussed. The possibility of using these mAb to obtain a markedly enriched CFU-GM progenitor population is also raised. 相似文献
82.
Dr. Berend van der Lei Charles R. H. Wildevuur Paul Nieuwenhuis Engbert H. Blaauw Freark Dijk Caesar E. Hulstaert Izaäk Molenaar 《Cell and tissue research》1985,242(3):569-578
Summary The ultrastructure of a new type of vascular graft, prepared from a mixture of polyurethane (95 weight %) and poly-L-lactic acid (5 weight %), was examined six weeks after implantation into the abdominal aorta of rats. These microporous, compliant, biodegradable, vascular grafts function as temporary scaffolds for the regeneration of the arterial wall.Smooth muscle cells, covering the grafts, regenerated a neo-media underneath an almost completely regenerated endothelial layer (neo-intima). These smooth muscle cells varied in morphology from normal smooth muscle cells to myofibroblasts. They were surrounded by elastic laminae and collagen fibers.Macrophages, epithelioid cells, multinucleated giant cells, fibroblasts and capillaries were present in the disintegrating graft lattices. The epithelioid cells and multinucleated giant cells engulfed polymer particles of the disintegrating grafts.The regeneration of the endothelial and smooth muscle cells is similar to the natural response of arterial tissue upon injury. The presence of macrophages, epithelioid cells, multinucleated giant cells, fibroblasts and capillaries in the graft lattices resembles the natural response of tissue against foreign body implants. Both of these responses result in the formation of a neo-artery that possesses sufficient strength, compliance and thromboresistance to function as a small caliber arterial substitute.Supported by Grant nr. 82.042 from the Dutch Heart Foundation 相似文献
83.
Cloning of the pectate lyase genes from Erwinia carotovora and their expression in Escherichia coli 总被引:11,自引:0,他引:11
A hybrid cosmid coding for pectate lyase (PL) activity was identified from an Erwinia carotovora genomic library by an immunological screening method. A 7-kb DNA fragment was identified which codes for three proteins identical in size to proteins with PL activity purified from E. carotovora culture supernatants. The three proteins had apparent Mrs of 41, 44 and 44 X 10(3) as estimated by SDS-PAGE. None of the PLs were exported from Escherichia coli strain HB101 but all were found in the periplasmic space. Plant tissue was macerated by the PLs made in E. coli. 相似文献
84.
The araBAD operon of Salmonella typhimurium LT2. I. Nucleotide sequence of araB and primary structure of its product, ribulokinase 总被引:6,自引:0,他引:6
Hybrid plasmids containing the araBAD operon of Salmonella typhimurium LT2 were characterized by Southern blot and genetic analyses. The nucleotide sequence of araB was determined. The araB gene product, ribulokinase (EC 2.7.1.16), was purified and the results of amino acid composition analysis and partial amino acid sequence are in agreement with predictions from the DNA sequence. Ribulokinase is 569 amino acid residues long and has a calculated Mr of 61 793. Ribulokinase shares significant homology with xylulose kinase from Escherichia coli. Codon usage in the araB gene does not favor those codons which have intermediate codon-anticodon binding energy. 相似文献
85.
外源蜕皮激素对蓖麻蚕蛹发育的效应 总被引:2,自引:1,他引:1
本文报道蓖麻蚕蛹在室温28℃下的卵巢发育过程,以及外源20-羟基蜕皮酮对蚕蛹发育的影响。正常蛹在任何发育期内注射20-羟基蜕皮酮后,全部仍羽化成蛾,但蛹期延长约1至4天。无脑蛹经注射后出现蛹——蛾的变态,发育情况因剂量而不同:注射0.1微克后约有半数蛹发育成蛾;注射2微克羽化率较高,卵巢管的发育也最好;4微克或更高的注射量能使全部蛹发育成蛾,但卵巢管多少有些不正常。注射量超过5微克时,蛾体较小,颜色浅黄,没有或只有很少的鳞片。蛹的发育天数随剂量的增大而减少。经外源20-羟基蜕皮酮处理后,无论是有脑蛾或是无脑蛾的卵粒都明显地比正常蛾的卵粒大。当超过一定的注射量时,注射量越大,蚕蛾的自动蜕壳能力越差。 相似文献
86.
傅家瑞 《植物生理与分子生物学学报》1985,(1)
水浮莲种子是一种奇特的需光种子。在黑暗中,GA_2或BA均不能代替光照诱导萌发,可是0.1μl/l乙烯却能引起部分种子萌发,在1000μ1/1乙烯的作用下,发芽率可达80%,接近全光照处理的萌发水平(91%发芽率)。ACC也能诱导水浮莲种子的萌发,0.1 mM浓度可获30%发芽率。在较短光照下,ACC对种子萌发有增效作用。在光照前应用ACC,其诱导效应大于两者同时施用。在照光萌发中,种子的内源ACC含量及乙烯释放量均显著增加。CoCl_2和AOA均能抑制光的诱导萌发。推论光打破休眠诱导萌发的作用是与乙烯的生成密切相关。 相似文献
87.
88.
.王秋圃;.钱敏之;.傅萼辉;.梁红莉 《武汉植物学研究》1985,3(1):89-92
根据中朝两国政府文化合作协定,中国科学院外事局在院内组织了糖槭树考察团(四人)于1984年7月中、下旬赴朝鲜民主主义人民共和国考察,得到朝方自然保护联盟中央委员会及其有关部门、单位的热情接待和大力支持,使这次考察获得圆满成功。现仅就朝鲜木本糖料植物的研究概况报道如下: 相似文献
89.
细菌(Pseudomonas moltophilia)与hCG及LH有特异的亲和力,实验发现,细菌之生长曲线与hCG结合活性成平行关系,96小时达高峰,细菌之培养液中含有可溶性结合蛋白,该蛋白经硫酸铵沉淀(80%饱和度)、Sephadex G-100柱层析、DEAE-纤维素柱0.5mol/L NaCl梯度洗脱,再过Sepharose CL-AB柱,收集之活性部分经SDS电泳测得其分子量为70,000,凝胶层析测Stokes radius为41A,Schiff氏染色未见着色带。 相似文献
90.