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991.
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Long-term in vitro culture of murine mast cells. III. Discrimination of mast cells growth factor and granulocyte-CSF 总被引:10,自引:0,他引:10
Long-term in vitro growth of murine mast cells was dependent on the presence of a mast cell growth factor (MCGF) present in media conditioned by mitogen-activated splenic leukocytes or by various murine leukemic cell lines. MCGF shared a number of properties with granulocyte colony-stimulating factor (G-CSF). Both factors were present in media conditioned by the myelomonocytic leukemic WEHI-3 and the T cell lymphoma, LBRM-33 cell lines. They were relatively sensitive to trypsin treatment, and were resistant to boiling temperature. NZB mice that failed to respond to WEHI-3-derived G-CSF also failed to respond to MCGF. MCGF differed from G-CSF, however, in sensitivity to neuraminidase and lactoferrin, an inhibitor of macrophage CSF production, suppressed G-CSF production by WEHI-3 cells without affecting MCGF production. Furthermore, peritoneal cells produced G-CSF but not MCGF when stimulated with lipopolysaccharide. In vitro production of MCGF by normal spleen cells required the presence of T lymphocytes and is relatively macrophage-independent. The role of T cells in the maturation and growth of mast cells and the physiologic function of MCGF are discussed. 相似文献
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996.
Nineteen percent of the approximately 30,000 members of the Yale community aged 18 through 59 received swine influenza monovalent vaccine (A/New Jersey/1976) during the three days of a mass immunization program in Nov. 1976. Based on 1508 card questionnaires received, 71.2 percent of the vaccine recipients experienced a sore arm, 23.4 percent headache, 13.4 percent chilliness, and 9.7 percent feverishness or fever. The sore arm was judged as severe in 5.9 percent as was the headache in 4.2 percent. Other reactions were regarded as severe in less than 2 percent. All reactions were reported more commonly by women than mean and all decreased with age.Serologic tests carried out at the start of the immunization period revealed that influenza A/New Jersey/1976 antibody was absent from 78.6 percent of the recipients; almost all persons under 25 lacked this antibody. A significant antibody rise occurred in 78.3 percent of those receiving a single dose of monovalent vaccine. Somewhat better antibody responses occurred in 36-59 year olds than in those age 17-25 (84.9 vs 75.5 percent); the geometric mean antibody titer was also much higher (1:136.8 vs 1:31.2). However, the presence of pre-existing homologous antibody did not significantly improve the antibody response to the vaccine. Cross-reacting antibody rises to A/Victoria/1975 were found in 16.2 percent of the recipients of monovalent vaccine. 相似文献
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998.
Yorke G. Jacobson Melvin Keller Eldred D. Mundth Alfred J. Defalco James E. Mc Clenethan 《The Western journal of medicine》1966,105(2):93-96
Oxygen therapy at atmospheric and increased pressure was used in the treatment of experimental hemorrhagic shock. Arterial gases, pH, lactate and pyruvate were determined and compared. Survival was carefully followed and complete pathological evaluation was carried out. The results showed no difference between control animals and those in the hyperbaric oxygen therapy group. It was concluded that hyperbaric oxygen therapy post facto did not influence the metabolic or survival data in this experiment. 相似文献
999.
Leaf disks of red beet plants (Beta vulgaris) accumulate betanin when cultured on agar media. Betanin accumulation is completely inhibited by cycloheximide. Pigment production is stimulated by light and sucrose. Kinetin and sucrose are ineffective in promoting pigment synthesis in the dark. It is suggested that the initial response triggering pigment production occurs at the gene level. The amino acids dihydroxyphenylalanine and tyrosine have no efrect on pigment production. 相似文献
1000.
Lysolecithin markedly stimulated membrane-bound UDP-galactose:glycoprotein galactosyltransferase. The parent molecule lecithin, phosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidic acid, lysophosphatidic acid or glycerophosphorylcholine did not activate the enzyme suggesting that both fatty acyl- and phosphorylcholine groups are required for the enzyme activation. The dose-effect of lysolecithin showed sigmoidal kinetics and the Vmax of the enzyme was increased several-fold by lysolecithin. Saturating amounts of Triton masked the effect of lysolecithin. Pre-incubation with phospholipase A also activated the enzyme. A possible role of membrane lysolecithin is indicated in regulating the enzymes of glycoprotein synthesis. 相似文献