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651.
B. A. Battelle E. A. Kravitz H. Stieve 《Cellular and molecular life sciences : CMLS》1979,35(6):778-780
Summary Radiochemical precursor compounds for neurotransmitters were incubated withLimulus ventral nerve photoreceptor preparations. Octopamine was preferentially synthesized by a photoreceptor rich fraction of the nerve, acetylcholine was made by a photoreceptor poor fraction, and -aminobutyric acid was made about equally well in both fractions. The possibility that the ventral nerve photoreceptor cells serve a neurosecretory function in the adultLimulus is discussed.From the Neurobiology Course, Marine Biological Laboratory, Woods Hole, Mass. The Neurobiology Course is supported by grants from the Grass, Sloan and Sandoz Foundation and from Merck, Sharp and Dohme Research Institute. 相似文献
652.
H. Goldman R. Fischer N. Nicolov S. Murphy 《Cellular and molecular life sciences : CMLS》1975,31(3):328-330
Zusammenfassung Die i.v. Verabreichung von LSD an Ratten steigert den Blutkreislauf im Hirnstamm sowie im frontalen und parietalen Cortex selektiv. Es wurden durch 6-Nor-LSD, 2-Methyl-LSD und
8, 9-LSD weder wahrnehmbare Verhaltensänderungen noch Änderungen des regionalen Blutkreislaufs verursacht. 相似文献
653.
Zusammenfassung Verabreichung von Isoprotenerol, eines -adrenergen Agonisten, induziert einen signifikant höheren Anstieg der Aktivität der Serotonin-N-Acetyltransferase in der Epiphyse von spontan hypertensiven, im Vergleich mit normotensiven, Rattenmännchen. Derselbe Unterschied wurde auch bei Weibchen beobachtet, jedoch liegen die Aktivitätswerte bei spontan hypertensiven Männchen allgemein höher. Die durch Isoprotenerol erhöhte Induktion der Serotonin-N-Acetyltransferase erzeugt hinsichtlich der Catecholamine in den Pinealozyten von spontan hypertensiven Ratten eine veränderte Reaktivität der Achse -Rezeptor-Adenylzyklasesystem-Serotonin-N-Acetyl transferase. 相似文献
654.
Summary The extra-DNA body was found, for the first time, in oocytes of an insect with telotrophic ovary. Dispersion of this body is accompanied by an enormous increase of nuclear volume and production of multiple nucleoli. It is suggested that the extra-DNA contains a huge mass of nucleolus organizers.This research was supported in part by funds from the Cytobiology Committee of the Polish Academy of Science. 相似文献
655.
Summary The paper describes a hexagonal array of nuclear pores in a non-redundant region of the nuclear envelope underlying the basal surface of the rat spermatozoon head. It is concluded that intranuclear material protruding through these pores is the cause of the characteristic rows of circular bumps found in surface replicas of this region. 相似文献
656.
Summary The crucial functional groups of phorbol-12-myristate-13-acetate (PMA) are superimposable with those of the glucocorticoid cortisol in a unique manner which suggests a mechanism for PMA activity, i.e. the alkylation of a cortisol receptor. 相似文献
657.
P. Pani A. Sanna M. I. Brigaglia A. Columbano L. Congiu 《Cellular and molecular life sciences : CMLS》1976,32(11):1449-1451
Summary Acute toxicity induced by DMN was partially prevented by previously administering methyl mercuric chloride (MMC), a chemical inhibitor of the drug metabolizing enzyme system (DMES). We have studied the early changes occurring during the course of DMN-intoxication, namely disaggregation of polysomal profiles and necrosis, evaluated morphologically and by the release of S-GPT.This work was supported by Consiglio Nazionale delle Ricerche, Roma, Italy. 相似文献
658.
Summary The serum activities of aspartate aminotransferase, alanine aminotransferase, -hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed. 相似文献
659.
Summary The C-11 proton of an aprophine possessing a C-1,2 methylenedioxy group falls relatively upfield between 7.47 and 7.86. Additionally, the i.c.s. for the two protons of the methylenedioxy group is large (4–12 Hz). The presence of a methylenedioxy at C-3,4 in a phenanthrene alkaloid also results in an upfield shift ( 8.95–9.00) of the C-5 proton.This project was supported by NIH research grant No. HL-12971, awarded by the National Heart and Lung Institute, PHS/DHEW. 相似文献
660.
Summary The effect of dipyridamole on platelet phospholipids has been studied. After the platelet incubation with dipyridamole, a 38% reduction in the concentration of the sphingomyelin and a 21% increase in phosphatidyl choline were produced. 相似文献