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991.
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
992.
Molecular structure of r(GCG)d(TATACGC): a DNA--RNA hybrid helix joined to double helical DNA 总被引:20,自引:0,他引:20
A H Wang S Fujii J H van Boom G A van der Marel S A van Boeckel A Rich 《Nature》1982,299(5884):601-604
The molecule r(GCG)d(TATACGC) is self-complementary and forms two DNA--RNA hybrid segments surrounding a central region of double helical DNA; its molecular structure has been solved by X-ray analysis. All three parts of the molecule adopt a conformation which is close to that seen in the 11-fold RNA double helix. The conformation of the ribonucleotides is partly determined by water molecules bridging between the ribose O2' hydroxyl group and cytosine O2. The hybrid-DNA duplex junction contains no structural discontinuities. However, the central DNA TATA sequence has some structural irregularities. 相似文献
993.
994.
G Barchewitz F Binon A Cier H Tuchmann-Duplessis 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(4):409-411
When orally administered, 5-(3-diméthylamino propyliden)-benzofuro [2,3-c] benzoxepin-1, which antagonizes several biogenic amines, is slightly sedative and has also endocrinological properties in the Rat, induces the appearance of localized lesions of uterine stroma in 2 to 16% of the animals. The cytological picture could suggest a tumorogenesis. In fact, these lesions represent a non-tumoral reactional hyperplasia with nuclear abnormalities due to a hormonal stimulation. 相似文献
995.
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
996.
Julia Szekeres G. Fabian A. S. Pacsa B. Pejtsik 《Cellular and molecular life sciences : CMLS》1981,37(5):515-516
Summary Lymphocyte responsiveness was found to be decreased in pregnant and increased in habitually aborting women. This is attributed to a dialyzable serum factor(s), that can be removed from the surface of lymphocytes by repeated washing. 相似文献
997.
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
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