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981.
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
982.
983.
J. B. Gibson A. V. Wilks G. K. Chambers 《Cellular and molecular life sciences : CMLS》1982,38(6):653-654
Summary A 3rd allele at theAdh locus,Adh
FCh.D., has been found at polymorphic frequencies in natural populations ofD. melanogaster. The ADH-FChD enzyme has properties distinct from those of the 2 more common forms of ADH. TheAdh polymorphism should now be analyzed as a triallelic system. 相似文献
984.
A transposon in Streptococcus faecalis with fertility properties 总被引:60,自引:0,他引:60
985.
986.
Effect of conditioned media on nerve cell differentiation 总被引:2,自引:0,他引:2
M. Sensenbrenner G. G. Jaros G. Moonen B. J. Meyer 《Cellular and molecular life sciences : CMLS》1980,36(6):660-662
Summary Glial conditioned medium strongly stimulates the morphological maturation of cultured neuronal cells, while fibroblast and meningeal conditioned media have weaker effects.Acknowledgment. We acknowledge the expert technical assistance of Mrs M.F. Knoetgen. 相似文献
987.
N Casadevall C Lacombe B Varet 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(24):2589-2592
Marrow specimens of patients with polycythemia vera rise to erythrocytic colonies in vitro without addition of erythropoietin to the culture. This behavior was never observed with marrow cells of normal subjects or secondary erythrocytosis. These results indicate that the sensitivity of some erythrocytic progenitor cells to erythropoietin is altered in polycythemia vera. 相似文献
988.
B. Skoog 《Cellular and molecular life sciences : CMLS》1980,36(10):1157-1158
Summary A chromatographic method is described for 80% removal of polyethylene glycol of different types, 600–6000, from human immunoglobulin preparations. Bio-beads SM-2 were used in batch procedures or packed on a 16×100 mm column. The polyethylene glycols were desorbed with 75% ethanol. 相似文献
989.
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
990.
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