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691.
Summary A new enantiomeric sesquiterpene alcohol named (–)-maalian-5-ol was isolated from the liverwort, and the structure and absolute configuration was determined to be the stereostructureI by chemical and spectral evidence.The authors express their gratitude to Dr H. Inoue, National Science Museum, for identification of the liverwort, and Prof. T. Tokoroyama, Osaka City University, for sending of the data of (–)--maaliene and (+)-selina-5,11-diene. Thanks are also due to the Ministry of Education for financial support of this work.  相似文献   
692.
It was shown that, in physiological concentrations, insulin enhances, in vitro, the immunological phagocytosis of sensitized sheep erythrocytes by cultured mouse peritoneal macrophages. Insulin seems to stimulate macrophage phagocytosis as a cholinomimetic agonist by increasing the intracellular levels of cyclic GMP.  相似文献   
693.
Field stimulation of isolated, spirally-cut cervix from day-22 pregnant rats produced contractions which could be inhibited by tetrodotoxin or hyoscine and potentiated by propranolol. The rat cervix would appear to receive both cholinergic and noradrenergic innervations whose transmitters activate muscarinic cholinoceptors and beta-adrenoceptors respectively.  相似文献   
694.
Linear unintegrated DNA of Schmidt-Ruppin Rous sarcoma virus, subgroup D (SR-RSV-D), was digested with SmaI restriction endonuclease, analyzed by agarose gel electrophoresis, "blotted" by Southern's method and hybridized with a viral 32P cDNA. SmaI cleaves this DNA at five sites, two of which are localized at the ends of the provirus. Src and env genes seem not to be restrictied by SmaI cleavage.  相似文献   
695.
Summary 2 factors elaborated by distinct neurosecretory cells in the pars intercerebralis control moulting inPanstrongylus megistus. The 1st, originating probably in the A cells, activates the thoracic gland. The 2nd, produced by the A cells, acts at an earlier stage in a different way.Supported by CNPq., Brésil and DGRST (aide No. 76.7.0716).  相似文献   
696.
The enzymes which were extracted by autodigestion from the microsomal fractions of the pig kidney, liver and submaxillary gland and from the serum showed an immunochemical identity by a double immunodiffusion test. But the kidney enzyme had a different pI-value from the pI-values of the enzymes of other organs.  相似文献   
697.
G Kaiser  J Dietz  G Wiemer  D Palm 《Experientia》1979,35(4):453-455
During the maturation of red blood cells from rats after stress erythropoiesis, adenyl cyclase activity and beta-adrenoceptor density (pmoles/mg protein) decrease at distinctly different rates suggesting a different turnover of these membrane units.  相似文献   
698.
(3H)-Ouabain binding to liver and kidney preparations was utilized to estimate the number of Na+, K+-ATPase enzyme units in livers and kidneys from rats fed 2% corn oil supplemented or fat-free diets. The specific (3H)-ouabain binding in liver and kidney preparations from fatty acid deficient rats was increased approximately 40%, but the affinity of the binding sites for ouabain (Kd-value) remained unchanged. The increased concentration of Na+, K+-ATPase enzyme units observed in the essential fatty acid deficient rats may contribute to the reduced body fat accumulation and elevated heat production observed in these animals.  相似文献   
699.
Summary The low temperature EPR spectrum of a quickly reacted mixture of oxyhemoglobin and phenylhydrazine was studied. With the use of a computer, the spectral contribution of methemoglobin in the region of g=2 was subtracted. The remaining spectrum was that of an axial free radical (g=2.00, g=2.06) having the magnetic parameters of superoxide anion. In the presence of superoxide dismutase, this axial radical was not seen, confirming that superoxide anion is indeed generated by the reaction.The portion of this investigation carried out at the Albert Einstein College of Medicine was supported in part by US Public Health Service Research Grant HL-93399 from the Heart and Lung Institute and by National Institute Contract Nol-CP-55606 to J.P. This is communication No. 378 from the Joan and Lester Avnet Institute of Molecular Biology.Predoctoral fellow in the Medical Scientist Training Program (United States Public Health Service Grant 5-TO-5-GM 01669-12) at the New York University School of Medicine.Recipient of a grant-in-aid from the New York Heart Association.  相似文献   
700.
Summary A method able to monitor transmitted light acoustically is described. It makes use of an amplifier of light variations, provided with a photocell and a sound device, a photometer, an optic probe and a special support.Acknowledgments. The author would like to thank Dr Leonard Salzarulo, chairman of the Physics Department of the New Jersey Institute of Technology, for the critical reading of the paper. The author acknowledges the invaluable assistance of Prof. Araldo Ramundo of the Centro Regionale Professionale in Cosenza, Italy, for designing and assembling the electronic amplifier. Appreciation is also extended to Prof. Giuseppe Battendieri of the Liceo Scientifico Enrico Fermi in Cosenza, Italy, for the schematic reproduction of the apparatus.  相似文献   
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