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921.
922.
923.
Summary Chronic administration of alcohol to well-nourished rats led to striking changes in the small intestinal cell population. The present experiments corroborate the view that alcohol is directly toxic to the small intestine.The authors wish to thank Mr.P. R. Gaspar for the technical assistance. 相似文献
924.
Early removal of the optic cup of the chick embryo prevents innervation of the contralateral optic lobe. This reduces the rate of development od citrate synthetase. The posthatch increase of the level of this enzyme related to oxidative metabolism is not impaired by denervation of the chick optic lobe. 相似文献
925.
Adenosine-induced slow ionic currents in the Xenopus oocyte 总被引:11,自引:0,他引:11
Adenosine and its 5'-phosphorylated congeners evoke specific membrane-mediated responses in excitable tissues. Available data suggest that inhibition of the target cell occurs due to hyperpolarization, and in some preparations a compound effect of ATP (excitation and inhibition) has been found. However, the ionic mechanism of the purinergic-mediated response has not been studied by standard intracellular voltage-clamping techniques. Recently, we have discovered purinergic receptors in the Xenopus oocyte, a well defined giant cell amenable to rigorous electrophysiological and biochemical studies. We report here that in these cells, adenosine-induced slow membrane responses consisted of an early depolarizing (D) transient current carried by Cl ions, followed by a steady hyperpolarizing (H) current involving K+ ions. The relative potency sequence for the D current was ATP congruent to ADP greater than AMP congruent to adenosine; this order was reversed for the H current. 相似文献
926.
C. L. Kaul P. K. Talwalker R. S. Grewal 《Cellular and molecular life sciences : CMLS》1976,32(8):1072-1074
Summary The sympathetic nervous system in the rat does not play any significant role in the streptozotocin-induced and tolbutamipe-induced hypoglycemia. 相似文献
927.
928.
A. K. Chopra S. K. Jain V. K. Vinayak G. K. Khuller 《Cellular and molecular life sciences : CMLS》1978,34(11):1457-1458
Summary The phospholipid composition ofDipylidium caninum has been studied. Chloroform-methanol-soluble fraction amounted to 2.4% and phospholipids to 0.5% of the wet weight of the parasite. Phosphatidyl choline and phosphatidyl ethanolamine represented the bulk of the phospholipids, whereas phosphatidyl serine, phosphatidyl inositol, lysolecithin and lysophosphatidyl ethanolamine were present in minor amounts. Sulfatides were also identified in this parasite. 相似文献
929.
R S Manalis 《Nature》1977,267(5609):366-368
930.
Glucose-phosphorylating enzyme with high Km in human brain 总被引:1,自引:0,他引:1
H S Bachelard 《Nature》1967,215(5104):959-960