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991.
992.
E. Valadé del Rio 《Cellular and molecular life sciences : CMLS》1982,38(7):790-792
Summary A mutant strain containing acinnabar allele (cn
rbr
,rojo brillante) is reported, that produces wild-type revertants at thecinnabar (cn) locus. Incn
rbr
/cn heterozygotes the rate of mutation is highly increased. The presence of a mutator agent acting premeiotically is indicated.D.L. Lindsley and E.H. Grell, Genetic variations ofDrosophila melanogaster. Carnegie Institution of Washington, Washington, 1968; Publication No. 627. 相似文献
993.
Summary The regulation of ethylene synthesis, in relation to the presence of a new cell wall, has been investigated forNicotiana sylvestris leaf protoplasts. It is clear that the production of ethylene is not controlled by the new wall, which has no action on the ethylene formation. The addition of dichlorobenzonitrile to cultivated protoplasts causes the inhibition of wall formation, without any other apparent deleterious effects. 相似文献
994.
995.
Effect of chloroform on charge movement in the nerve membrane 总被引:2,自引:0,他引:2
996.
Summary The chloroform extract of anthers ofSolandra nitida contains 3-acethyl-6-methyl-1,2-pyran-2,4(3H)dione (dehydroacetic acid) as one of the main products. 相似文献
997.
998.
999.
J H Saurat E Gluckman L Didierjean 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(4):355-356
By means of indirect immunofluorescence with human sera it has been demonstrated that cytoplasmic components of the basal cell layer showed antigenic differences as compared to the upper cell layers. Moreover there were differences whether the cells were involved in a mucous, a parakeratinized or an orthokeratinized differentiation. 相似文献
1000.
HLA-restricted T-cell recognition of Epstein-Barr virus-infected B cells 总被引:23,自引:0,他引:23
In mice the cytotoxic T-cell response to several types of virus is influenced by genes within the major histocompatibility complex; in particular, genetic control is exercised at the effector cell level through a requirement that virus-specific cytotoxic T cells recognise viral antigens in association with H-2K and H=2D region gene products on the surface of infected cells. In man the restriction which the analogous HLA-A, -B and -C-region gene products might place on virus-specific T-cell function is still in dispute. The earliest and most controversial evidence concerns the Epstein-Barr virus (EBV), a B lymphotropic agent which causes infectious mononucleosis (IM) and which induces an unusually vigorous T-cell response; cytotoxic T cells from IM patients' blood were shown to be EBV-specific yet, in contrast to mouse systems, apparently free of any obvious HLA restriction. Since then T-cell recognition of EBV-infected B cells has assumed particular significance as a model system for the study of cytotoxic T-cell function in man. This report describes the results of a new approach clearly indicating that HLA-A and -B region products do indeed have a role in this system. 相似文献