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961.
962.
Summary Recent evidence has revived the idea that translocation of macromolecules between nucleus and cytoplasm may be regulated via expansion and contraction of the entire diameter of the nuclear pore complex. The present investigation does not support this hypothesis.Acknowledgments. We are indebted to Dr J.H.M. Willison for discussion of his and Dr Rajaraman's results before their publication. We also wish to thank Dr C. Thurston, Dr D.H. Williamson and Dr K. Lambert for providing some of the specimens used in this investigation. N.J. Severs acknowledges the support of the Science Research Council and the Cancer Research Campaign. 相似文献
963.
D. N. Wheatley 《Cellular and molecular life sciences : CMLS》1982,38(7):818-820
Summary Incorporation of amino acids into mammalian cell protein shows immediate linear kinetics when measured at intervals as small as 5 sec. Free amino acids equilibrate instantaneously across the cell membrane, acting as the precursor supply. Glycine, which does not initially show linear kinetics, may have a significant endogenous precursor supply, but this is not the acid-soluble pool.Acknowledgments. I thank the University of Aberdeen Medical Faculty Endowment Fund for support, and Mrs J. Robertson for technical assistance. 相似文献
964.
Summary Octopamine and proctolin at concentrations below 10–8 M reversibly induce a spontaneous rhythmic depolarization which occurs in body-wall muscles ofLucilia larvae. The effect appears to be postsynaptic and mediated by receptors specific for each substance.This work was supported by NIEHS grant No. ES00814 and EPA grant No. R804345. 相似文献
965.
966.
M. Hiramatsu K. Hatakeyama N. Minami 《Cellular and molecular life sciences : CMLS》1980,36(8):940-942
Summary Submaxillary gland saliva induced by phenylephrine from male mice was highly toxic to guinea-pigs, rats and hamsters, whereas the toxicity was relatively low to mice. One of the toxic components in the saliva was isolated as a kallikrein-like enzyme. 相似文献
967.
968.
969.
Lipopolysaccharides from several bacteria were selectively degarded by gut juice of the snail Helix pomatia with extensive loss of anticomplementary activity and changes in the electrophoretic pattern in polyacrylamide gels. The gut juice had little effect on ketodeoxyoctonate content or immunodominant sugars. The lipid A moiety of the lipopolysaccharide appeared to be the main site of attack. 相似文献
970.
P Lemay N Pluquet de Temmerman A Tavitian J Bernard 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(24):2573-2575
A DNA complementary to the viral genome of C-type particles produced by a Mouse myeloma derived cell line (MF2 cell line) was synthesized. This cDNA was used as a probe to study the viral genome expression among the total RNA and the poly (A)-rich RNA extracted from the MF2 and Balb/c embryonic cells. As evidenced by molecular hybridization experiments, the presence of at least one endogenous Balb/c virus in the MF2 virus stocks is suggested. In the productive cells, the viral RNA sequences are expressed in the poly (A)-rich RNA fraction. 相似文献