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991.
G. Planz J. Bieber H. J. Mencke G. v. Bernuth 《Cellular and molecular life sciences : CMLS》1983,39(5):497-498
Summary Plasma catecholamine concentrations in 46 children of various ages were determined by a sensitive radioenzymatic assay. Noradrenaline levels were found to be in the same range as in adults, whereas adrenaline levels in a few of the children were abnormally high. 相似文献
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.
Summary Tremor induced by thiophene-2-aldoxime is enhanced or reduced in intensity and duration by agents which respectively interfere with or promote dopaminergic tone.This project was supported by a grant from the Lebanese National Research Council. We thank the following companies for the indicated drugs: Abbott (pargyline), Specia (chlorpromazine), Squibb (cinanserin). 相似文献
995.
H. Hervonen 《Cellular and molecular life sciences : CMLS》1977,33(9):1215-1217
Summary The 2 cholinesterase inhibitors, eserine and BW 284 C 51, inhibited the nerve fibre growth and differentiation of immature sympathicoblasts at low concentrations. The effect was nerve cell-specific and appeared in the course of the in vitro development, indicating that cholinesterases might play an important role in the early differentiation of sympathicoblasts. 相似文献
996.
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
997.
G. H. Rossmanith J. Unsworth R. D. Bell 《Cellular and molecular life sciences : CMLS》1980,36(1):51-53
Summary Small-amplitude sinusoidal displacements, in the frequency rang 4–100 Hz, were applied to intact whole frog sartorius muscle whilst in a state of tetanus. At low frequencies the muscle, was observed to do oscillatory work, while at higher frequencies it tended towards elastic behaviour. Frequency-response plots obtained were compared with those from other muscle preparations. Results were interpreted in terms of mechano-chemical transduction properties of muscle.The authors wish to thank the Australian Research Grants Commission for provision of the laser, and L. I. Patterson for construction of the mechanical apparatus. 相似文献
998.
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
999.
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
1000.
Zusammenfassung Nach Thalidomidverabreichung an trächtigen Ratten fanden wir Fruchtresorption und Anomalien am fünften Brustbeinkern der Föten. Weitere ergänzende Skelettuntersuchungen ergaben, besonders bei mittelgrossen Thalidomidgaben, Verknöcherungs-störungen an den Halswirbelkörpern. Andere Skeletteile zeigten keine Thalidomid-abhängigen Entwicklungsvariationen. 相似文献