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951.
Effector T lymphocyte line cells migrate to the thymus and persist there 总被引:15,自引:0,他引:15
Y Naparstek J Holoshitz S Eisenstein T Reshef S Rappaport J Chemke A Ben-Nun I R Cohen 《Nature》1982,300(5889):262-264
952.
953.
954.
Summary The changes in short-circuit current occurring when one or both solutions bathing the intestine of rat or guinea-pig mounted in flux chambers were recorded. The results with the guinea-pig can be explained in terms of diffusion potentials arising from the ionic replacements, and an electrogenic sodium pump, sensitive to ouabain, in the contraluminal membrane of the cell. In the rat, the situation is more complicated, and the enterocyte probably possesses an electrogenic sodium pump in the brush-border membrane. 相似文献
955.
Summary Melatonin, in concentrations up to 10–3
M, showed no effect on mitosis in cultures of HeLa or KB cells. However, when melatonin at 10–4
M was preincubated with HeLa cells prior to addition of 10–7
M colchicine, a reduction in the mitotic index, in comparison to colchicine alone, was observed.This work was supported by PHS Grant No. CA 16425. 相似文献
956.
957.
Retroviral antigens on gs- chf- leukocytes 总被引:1,自引:0,他引:1
It has recently been suggested that the endogenous retroviruses present in many different species might be involved during stimulation of the immune system of their hosts. We have now studied the expression of two avian retroviral antigens p27 and gp85 in chicken lymphoid cells by indirect immunofluorescence (IIF) and by complement-dependent microcytotoxicity (CDM). We have now found that these viral antigens are expressed in peripheral blood leukocytes of adults and embryos and in splenic and bursal lymphocytes of Spafas gs- chf- chickens but they are not expressed in fibroblasts cultured from the feather follicles of the same individual adult birds nor in fibroblasts cultured from embryos of the same flock. The differential expression of viral antigens in leukocytes may be related to a specific property or function of these cells. 相似文献
958.
Summary 4000 rads of mixed gamma neutron radiation administered to rhesus monkeys released a significant amount of histamine into their circulation. When the monkeys were treated with a mast-cell histamine depleter (compound 48/80) for 4 days and then irradiated, no increase in circulating histamine was seen. When 48/80 was given 20 min after irradiation, only a slight increase in histamine was seen, indicating that 4000 rads had released most of the mast-cell histamine. 相似文献
959.
Site specific integrative recombination of bacteriophage lambda involves unequal partners. The minimal phage att site is composed of approximately 240-base pairs and four distinct binding sites for Int protein, at least three of which are crucial for function. This 'donor site' recombines efficiently with a smaller 'recipient site' that lacks the extensive interactions with Int protein. 相似文献
960.
Human leukocyte and fibroblast interferons are structurally related 总被引:38,自引:0,他引:38
The coding sequences of the dDNAs of cloned human leukocyte interferon I and human fibroblast interferon show homologies of 45% at the nucleotide and 29% at the amino acid level. We conclude that the two genes were derived from a common ancestor. 相似文献