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761.
Summary A compact and easily assembled system of multiple organ-baths is described, in which use is made of readily available materials.Acknowledgment. G.E.R. was in receipt of the ruggles Gates Research Award. 相似文献
762.
T. Saito Y. Shibata T. Kurokawa N. Ishida 《Cellular and molecular life sciences : CMLS》1979,35(5):685-686
Summary The inhibitory effect of various purine derivatives on PHA-induced human lymphocyte blast formation was studied. Two nucleoside cytokinins, N6-benzyladenosine and N6-isopentenyladenosine, inhibited blast formation at concentrations as low as 10–6 M. However, the other cytokinins, which lacked the ribosyl residue at N9 position, had to be at the higher molar concentration of 10–4 before they could induce the same inhibitory effect. 相似文献
763.
V. Pliška M. Meyer-Grass N. Bersinger L. Carlsson P. Melin H. Vilhardt 《Cellular and molecular life sciences : CMLS》1980,36(10):1145-1146
Summary Lysine vasopressin tritiated at meta position of tyrosine (1.9 Ci/mmole) decomposes during a long storage period, mainly as a result of radiolysis. The loss of specific activity by isotopic exchange with water is slow. The nonlabelled peptide undergoes only very minute decomposition (polymerization). Specific radioactivity declines with a half life of 47.4 months.Acknowledgments. This research was supported by Swiss National Science Foundation, grant No.3.040.76 (V.P.). Some of the measurements (years 1969–70) were carried out at Roche Institute of Molecular Biology, Nutley, N.J., USA. 相似文献
764.
Y. Yaeger I. Nathan A. Dvilansky N. Meyerstein 《Cellular and molecular life sciences : CMLS》1979,35(12):1673-1674
Summary The effect of copper ions on the permeation of glycerol and its mono-, di-, and triacetate derivatives was studied in fresh and stored erythrocytes. Permeability was unchanged with storage. Acylated glycerols permeate the cells mainly by non-facilitated mechanism, as their transport is almost unaffected by copper ions.Portions of this work were included in the graduate thesis of Dr. Yaeger in partial fulfillment of the requirements for the M. D. degree.Acknowledgement. We thank Mrs Dalia Mazor for expert technical assistance. 相似文献
765.
Katherine H. Taber G. N. Fuller J. C. Stanley J. F. DeFrance R. C. Wiggins 《Cellular and molecular life sciences : CMLS》1980,36(1):69-70
Summary Rats were undernourished postnatally from birth through 20 days of age. They were subsequently tested for susceptibility to motor seizures kindled in hippocampus in adulthood. Compared to littermate control animals the postnatally undernourished rats were more susceptible to the kindling treatment. We conclude that early postnatal undernourishment has a permanent effect on susceptibility of the hippocampus to electrically-induced seizures.This work was supported by Public Health Service grant NS 13799, National Science Foundation grant GB 35532, and by Hoffman-LaRoche, Inc. 相似文献
766.
Summary Ionophore A23187 inhibited closure of the chick neural tube through its effects on cytoskeletal components.This study was supported in part by grants from the Research Council and the Charles and Johanna Busch Memorial Fund of Rutgers University. Ionophore A23187 was provided through the courtesy of Dr R.L. Hamill, Lilly Research Laboratories, Indianapolis, Indiana, USA. 相似文献
767.
768.
769.
770.
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