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451.
O. A. Reig J. V. Pincheira A. O. Spotorno P. Waller 《Cellular and molecular life sciences : CMLS》1972,28(2):225-227
Resumen En dos poblaciones deRattus rattus, una de Mehuin (Valdivia, Chile) y otra de Capripe (Monagas, Venezuela), se encontró un cariotipo de 2n=38 cromosomas en todos los individuos estudiados. Este cariotipo corresponde al que presentan en forma monomórfica otras poblaciones de la rata negra de América del Sur y de Italia, y diffiere del cariotipo normal de la especie, que es de 42 cromosomas. Se postula que las distintas poblaciones sudamericans deRattus rattus deben haber invadido el Continente, acompañando al hombre, en distintas irrupciones, a partir de una forma de 38 cromosomas de origen mediterráneo. 相似文献
452.
O. Eränkö R. L. Hunter A. I. Koskimies 《Cellular and molecular life sciences : CMLS》1973,29(9):1176-1178
Zusammenfassung Isoenzyme von Serumesterasen wurden zuerst mit Zelluloseazetat und dann mit einem Gradientgel von Polyakrylamid mit zweidimensionaler Elektrophorese bei der Ratte untersucht. Ein neues Band, das eine starke Albuminesteraseaktivität aufweist und unempfindlich gegen 10–3
M Physostigmin ist, wurde somit gefunden. Von 17 Esterasebändern waren 7 empfindlich auf Physostigmin, und 3 wurden auch durch Iso-OMPA gehemmt, während 284-C-51 gar keinen Effekt zeigte.
Supported by a grant from the Sigrid Jusélius Foundation, Finland. 相似文献
Supported by a grant from the Sigrid Jusélius Foundation, Finland. 相似文献
453.
Cerebral cortical blood flow in the rat. Effect of furosemide 总被引:1,自引:0,他引:1
454.
Summary An increase in venous pressure in the rat tail is known to result in acute edema. Acute venous stasis edema of the rat tail was induced by applying a force-controlled banding of standard tension (200 g) proximally for a period of 6–12 h. The hemodynamic changes of acute venous stasis edema were evaluated using non-invasive plethysmography, fluorescence angiography, computer thermography and invasive radioactive microsphere techniques. It is shown here that reduction of tail circulation to 40% of the control value is followed by prolonged vascular disorder characterized by genesis of reversible edema, increased total blood flow to the tail and decreased local cutaneous blood flow, without affecting the general hemodynamics. The cutaneous circulation (decreased blood flow) seems to be principally involved in the edemogenic response, whereas the deeper vessels (hyperemia) may or may not play a determinant role in acute experimental venous stasis edema in rats.Acknowledgment. The authors thank Mr G. Ponard for his technical assistance. 相似文献
455.
The in vitro characterization of the inhibition of mouse brain protein kinase-C by retinoids and their receptors 总被引:1,自引:0,他引:1
Dr F. O. Cope Mr B. D. Howard Dr R. K. Boutwell 《Cellular and molecular life sciences : CMLS》1986,42(9):1023-1027
Summary The mechanism of the in vitro inhibition of Ca2+-, phosphatidylserine-dependent protein kinase C (PK-C)2 by the purifiedholo (ligand-saturated) forms of cellular retinol-binding protein (cRBP) and cellular retinoic acid-binding protein (cRABP) was studied. We report here that i) the PK-C-inhibitory action ofholo-cRBP andholo-cRABP is due to their respective ligands, all-trans-retinol and all-trans-retinoic acid; ii) the reduced phosphorylation of theholo-retinoid-binding proteins and brain cytosolic proteins is not the result of a retinoid-induced soluble phosphatase or protease activity; iii) retinoids reduce PK-C affinity for calcium and phosphatidylserine in vitro; and iv) the structure-function activity of the retinoids and the specific interaction of these effect of retinoids on plasma membrane-associated PK-C activity pays a significant role in defining the early epigenetic aspects of PK-C-dependent tumor promotion and may be a physiological mechanism by which retinoids induce terminal differentiation in cell types that do not express soluble retinoid-binding proteins.We would like to thank Dr L.M. De Luca (NIH, USA) for his contribution of retinylphosphate, Dr H.N. Bhagavan (Hoffmann-La Roche) for his contribution of the arotinoids, and Merrill-Dow Corp. for their contribution of difluoromethylornithine. This work was supported by NIH Grants CA-34968, CA-07175, CA-22484, and CA-09020. 相似文献
456.
457.
458.
O. V. Subramanyam 《Cellular and molecular life sciences : CMLS》1984,40(12):1423-1424
Summary Blood sugars and foot muscle glycogen were measured in the mussel,L. marginalis after ablation of the cerebral ganglia, and in mussels injected with cerebral ganglionic extract 3 h after ablation. There is a rise in the blood sugar and decrease in foot muscle glycogen 3 h after operation, but no change in sham-operated controls. The effect of ablation is reversed by injecting brain extract into ablated mussels. No such effect could be seen in the controls. The results are suggestive of the presence, in the cerebral ganglia, of a hypoglycaemic factor similar to insulin. 相似文献
459.
460.
T. O. Olagbemiro 《Cellular and molecular life sciences : CMLS》1984,40(8):807-808
Summary Volatile components of the scent gland complex of the adult bug ofAspavia acuminata, an agricultural pest from Nigeria, have been identified by the technique of combined gas chromatograph-mass spectrometry. Of specific interest is the presence in the gland reservoir of hex-2-enal, 4-oxo-hex-2-enal and 4-oxo-oct-2-enal.The author is grateful to the Bayero University Research and Higher Degrees Committee for financial support, Dr B. W. Staddon for his valuable assistance, Dr D. E. Games for arranging mass spectral facilities. 相似文献