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51.
Enhanced susceptibility of target KMT-17 cells to activated macrophages by treatment with the antitumor agent bleomycin 总被引:1,自引:0,他引:1
Zhen-Yi Xu Masuo Hosokawa Kiyoshi Morikawa Hiroshi Kobayashi 《Cancer immunology, immunotherapy : CII》1986,23(1):46-50
Summary We observed that after KMT-17 cells had been treated with bleomycin (BLM), even with a dose as high as 160 g/ml, they were still able to form colonies in soft agar. We then studied the susceptibility of KMT-17 cells treated with BLM to activated macrophages. During a colony inhibition assay, BLM-treated KMT-17 cells were found to be much more susceptile to activated macrophages than nontreated KMT-17 cells, moreover, a tumor neutralizing assay showed that the growth of BLM-treated KMT-17 cells was also significantly inhibited by activated macrophages as compared with nontreated KMT-17 cells. Macrophages activated by both BLM and the Nocardia rubra cell wall skeleton were able to mediate such tumor inhibition activity in BLM-treated KMT-17 cells. Activated macrophages did not seem to have strong antitumor activity against nontreated KMT-17 cells in vivo, however, the life span of the rats which were inoculated i. p. with KMT-17 cells was significantly expanded after the tumorbearing rats were given BLM i.p. The data presented here suggest that not only does BLM have a direct tumoricidal effect on KMT-17 cells, it also regulates immunosensitivity of targets to immune effectors. We also discuss the mechanism for enhancing the susceptibility of KMT-17 cells to activated macrophages brought about by treatment with BLM.Supported in part by a Grant-in-Aid for Cancer Research from the Japanese Ministry of Education, Science, and Culture 相似文献
52.
Transformation of L cells with virus thymidine kinase genes introduced by red cell-mediated microinjection 总被引:2,自引:0,他引:2
Takashi Iino Mitsuru Furusawa Iwao Furusawa Masuo Obinata 《Experimental cell research》1983,148(2):475-480
Fusion of red cell ghosts containing foreign materials with cells results in the introduction of the materials into the cells (red cell-mediated microinjection). Until now, 'two-step dialysis' has mainly been used for trapping proteins in the ghosts. Large-sized materials such as DNA, however, are rarely trapped in the ghosts, since the holes in the red cell membrane caused by osmotic shock are too small for such materials to pass through. In this study, we improved the trapping technique. Some of the Hind III fragments of lambda phage DNA as well as proteins could be trapped in the ghosts when the mixture of these materials and red cells were frozen at -80 degrees C for a short period followed by quick thawing. Red cell-mediated microinjection using ghosts containing plasmid pBR322 linked with a Herpes simplex viral thymidine kinase (tk) gene brought about transformation of tk-defective L cells, the efficiency of transformation was 1 out of 20 000-60 000 cells fused with the ghosts. 相似文献
53.
Raman diagnosis of nucleic acid structure: sugar-puckering and glycosidic conformation in the guanosine moiety. 总被引:6,自引:6,他引:0 下载免费PDF全文
Y Nishimura M Tsuboi T Nakano S Higuchi T Sato T Shida S Uesugi E Ohtsuka M Ikehara 《Nucleic acids research》1983,11(5):1579-1588
Observations of Raman spectra of various nucleic acids indicate that the guanine ring breathing frequency is sensitive to the internal rotation angle around the glycosidic bond and to the conformation of the five-membered ring of the ribose residue that is directly connected with the guanine residue in question. It is found that 682 cm-1 for C2'-endo-anti, at 665 cm-1 for C3'-endo-anti, and at 625 cm-1 for C3'-endo-syn. A DNA octamer d(GpGpApApTpTpCpC) shows, in its aqueous solution, a broad Raman band at 680 cm-1 with a tail at 670 cm-1. This fact suggests that the guanosine residues in this oligomer take primarily C2'-endo-anti conformation but an appreciable amount of fluctuation of the ribose ring structure towards C3'-endo is involved. 相似文献
54.
Metabolism of -methylmalic acid by a soil bacterium 总被引:1,自引:0,他引:1
55.
Harry Brumberger Jeffrey L. Lipton Gary Dorfman Eileen Nakano 《The Biochemical journal》1974,143(2):495-496
Small-angle X-ray scattering measurements on native pig thyroglobulin in phosphate buffer, pH6.9, yield a radius of gyration of 6.4nm (64Å), a particle volume of approx. 1.5×103nm3 (1.5×106Å3), an axial ratio of 2.2:1 (assuming an ellipsoidal shape), and a solvation of 0.63g of solvent/g of protein. 相似文献
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Effect of dihydroergotamine and propranolol on dibutyryl cyclic 3',5'-AMP-induced lipolysis in isolated rat fat cells 总被引:1,自引:0,他引:1
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