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X. J. Musacchia M. Jellinek Th. Cooper 《Cellular and molecular life sciences : CMLS》1963,19(8):418-419
Zusammenfassung 20 h nach Bestrahlung mit letaler Röntgenstrahlendosis (2000 r) zeigten winterschlafendeCitellus tridecemlineatus Herabsetzung der Konzentration von Catecholaminen in Leber und Niere. Werden Veränderungen des Wassergehaltes im Gewebe mitberücksichtigt, so erscheint der Gehalt an myokardialen Catecholaminen unverändert.
Acknowledgments. This research was aided by Grants HE-06312, USPHS; and Ns G-271-62, NASA. The authors are grateful to DoctorD. E. Smith, Division of Biological and Medical Research, Argonne National Laboratory, for providing the ground squirrels and the facilities for their hibernation and radiation. 相似文献
Acknowledgments. This research was aided by Grants HE-06312, USPHS; and Ns G-271-62, NASA. The authors are grateful to DoctorD. E. Smith, Division of Biological and Medical Research, Argonne National Laboratory, for providing the ground squirrels and the facilities for their hibernation and radiation. 相似文献
64.
Patched acts catalytically to suppress the activity of Smoothened 总被引:22,自引:0,他引:22
Mutations affecting the transmembrane proteins Patched (Ptc) or Smoothened (Smo) that trigger ligand-independent activity of the Hedgehog (Hh) signalling pathway are associated with human tumours such as basal cell carcinoma (BCC) and medulloblastoma. Despite extensive genetic studies demonstrating the importance of these receptor components in embryonic patterning and cancer, the mechanism by which Ptc regulates Smo is not understood. Here we report that Ptc and Smo are not significantly associated within Hh-responsive cells. Furthermore, we show that free Ptc (unbound by Hh) acts sub-stoichiometrically to suppress Smo activity and thus is critical in specifying the level of pathway activity. Patched is a twelve-transmembrane protein with homology to bacterial proton-driven transmembrane molecular transporters; we demonstrate that the function of Ptc is impaired by alterations of residues that are conserved in and required for function of these bacterial transporters. These results suggest that the Ptc tumour suppressor functions normally as a transmembrane molecular transporter, which acts indirectly to inhibit Smo activity, possibly through changes in distribution or concentration of a small molecule. 相似文献
65.
Neanderthal DNA. Not just old but old and cold? 总被引:9,自引:0,他引:9
66.
Sahin E Colla S Liesa M Moslehi J Müller FL Guo M Cooper M Kotton D Fabian AJ Walkey C Maser RS Tonon G Foerster F Xiong R Wang YA Shukla SA Jaskelioff M Martin ES Heffernan TP Protopopov A Ivanova E Mahoney JE Kost-Alimova M Perry SR Bronson R Liao R Mulligan R Shirihai OS Chin L DePinho RA 《Nature》2011,470(7334):359-365
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James J. Cooper 《西北部美国博物学家》2011,42(1)
Various aspects of the reproduction and embryology of Walker Lake Lahontan tui chub, Gila bicolor , were investigated during the spring–summer period of 1976, 1977, and 1981. Tui chub were found to spawn in littoral regions of the lake beginning in late May or early June. Early in the season male chub substantially outnumbered females over the spawning grounds, with a normal 1:1 sex ratio gradually approached as the season progressed. The developmental period between fertilization to hatch-out was shortened by increases in water temperature. Selected stages of embryonic development are described from egg fertilization through post-hatch. 相似文献
69.
The present research brings new insights on the role of admixed corrosion inhibitors in the processes of cement hydration and rebar corrosion.The admixing of NaCl and the corrosion inhibitors in fresh mortar was found to alter the morphology and microstructure of the hardened mortar at the steel-mortar interfacial region.The admixing of the inhibitors increased the risk of carbonation of cement hydrates at the steel-mortar interfacial region,but partially displaced chloride ions. Chloride and the admixed in... 相似文献
70.
Immunoglobulin heavy-chain switching in pre-B leukaemias 总被引:3,自引:0,他引:3