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191.
Somatic translocation of antibody genes 总被引:36,自引:0,他引:36
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RNA-DNA hybrids at the cytological level 总被引:37,自引:0,他引:37
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Abnormal electroretinogram from a Drosophila mutant 总被引:21,自引:0,他引:21
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A. Ballio 《Cellular and molecular life sciences : CMLS》1991,47(8):783-790
During the last decade increasing attention has been directed towards the biochemical mechanisms responsible for the biological activity of phytotoxins. Studies on the mode of action of some non-host-selective phytotoxins, some following on from previous observations, have demonstrated a very specific interaction with particular components of the cell machinery, and have suggested the possible use of these phytotoxins as tools for the investigation of important biochemical processes. This review article reports and discusses results of studies carried out in the 1980s with seven non-host-selective fungal toxins: brefeldin A, cercosporin,Cercospora beticola toxin, fusicoccin, ophiobolins, tentoxin, and zinniol. Each of these interferes with the life of the host by interacting with a different biochemical target. 相似文献
200.
G. Deby-Dupont J. Pincemail A. Thirion C. Deby M. Lamy P. Franchimont 《Cellular and molecular life sciences : CMLS》1991,47(9):952-957
In order to obtain a radioimmunoassay (RIA) technique for the measurement of human plasma myeloperoxidase (MPO), we purified the enzyme from polymorphonuclear granulocytes (neutrophils), and compared three methods of labeling it with125Iodine: chloramine T, lactoperoxidase, and an original technique of self labeling based on the ability of the enzyme to oxidize and bind125I in the presence of H2O2. The chloramine T technique produced a degraded protein, as well shown by a high non-specific binding of tracer to antibody. The lactoperoxidase technique did not succeed in labeling MPO with an adequate specific activity. In contrast, the self-labeling method gave a stable tracer with a specific activity of 23 Ci/gmg MPO (85 MBq), a satisfactory level of immunoreactivity, and a low-specific binding (3%). After labeling, purification of tracer was achieved by gel filtration chromatography in phosphate buffer (0.05 M; pH7) to which 0.1% poly-L-lysine was added. The labeled molecule remained stable for 40 days and could be used for RIA with a polyclonal antibody raised in rabbits. 相似文献