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1.
Summary The PGE2-induced cyclic AMP accumulation in the rat anterior pituitary in vitro is inhibited by [desamino1]-, [desamino1] [descarboxy14] and [d-Lys4]-somatostatin similarly to somatostatin, while the [descarboxy14]-somatostatin exhibits reduced activity; [d-Lys9]-somatostatin is ineffective at a higher concentration.The authors acknowledge the technical assistance ofG. Alexander. F. Bellini, D. Mangerel andJ. Rochon and thank Dr.G. Schilling and his associates for the analytical data.  相似文献   

2.
Summary The catalysis of H2O2 decomposition by Cu2+-complexes of RNA and DNA has been investigated. It is shown that both complexes decompose H2O2, but only the Cu2+-RNA-system shows peroxidative activity too, e.g. only in this case the nucleotide bases are degraded. Thermal denaturation of DNA also leads to a Cu2+-complex with peroxidative activity, the latter being dependent on the degree of denaturation.

V. Mitteilung:S. Petri, H. Sigel undH. Erlenmeyer, Helv. chim. Acta49, 1778 (1966).

12. Mitteilung überMetallionen und H 2 O 2; 11. Mitteilung:H. Ch. Curtius, P. Anders, R. Zell, H. Sigel undH. Erlenmeyer, Helv. chim. Acta49, 2256 (1966).  相似文献   

3.
Riassunto La somministrazione dietetica di vitamina B12 e di acido orotico determina un aumento della incorporazione dellal-serina C14 nello RNA solubile del fegato di pulcino carente di B12, mentre non è in grado di influenzare quella dellal-leucina14C e dellal-metionina14C.  相似文献   

4.
Summary The incorporation of tyrosine-2-14C-15N into xanthocillin X (I) byPenicillium notatum Westling has been investigated showing that nitrogen of the isocyano groups originates from tyrosine, which is incorporated as C6-C2-N-unit.

1. Mitteilung:H. Achenbach undH. Grisebach, Z. Naturforsch.20b, 137 (1965).  相似文献   

5.
Summary Using metal-ion buffers it was possible to remove Zn2+, Mg2+ and Mn2+ ions of pig kidney alkaline phosphatase reversibly. The dissociation constants obtained are KEMg:4·10–7 M, KEMn:4·10–8 M and KEZn:8·10–13 M (22°C, pH:9.6, :0.07).Acknowledgement: The authors thank Dr.H. U. Wolf for helpful suggestions and valuable discussion and MissH. Köth for technical assistance.  相似文献   

6.
In intact tissue, [d-Ala2,MePhe4, Gly-ol5] enkephalin (10–5 M;-ligand), diminsihed short-circuit current (Isc) and increased water, Na+ and Cl net fluxes in vitro under open circuit conditions; it also inhibitedL-valine absorption andL-valine-dependent variations of short-circuit current (Isc, val). Naloxone (10–6 M) antagonized these effects. In the absence of the muscularis and myenteric plexus this enkephalin or morphine (-ligand) reduced Isc and Isc, val. These enkephalin effects occurred at different times. Different concentrations of enkephalin were tested for their effects on Isc, val. [d-Ala2,d-Leu5] enkephalin (mainly a -ligand) significantly decreased Isc but not Isc, val. The reduction ofL-valine absorption does not depend on the effects on basal ion transport. Interaction of opioids with-receptors located in the submucosal plexus and/or in the epithelial cell accounts for this reduction. This enkephalin effect seems to be at least partially under the control of the myenteric plexus.  相似文献   

7.
Résumé La valeur deGh+Goh peut être obtenue en utilisant des solutions aqueuses de certains composés organiques contenant Cu2+ et/ou Fe3+. Les ions métalliques sont réduits par H et par les radicaux produits par l'oxydation des composés organiques par OH. A concentration convenable des réactifs, on a;G Fe 2+ =G H+G OH.  相似文献   

8.
Summary Psophus stridulus L. andOedipoda coerulescens L. were fed or injected with solutions of Na 2 35 SO4 and35S-l-cystine. The radioactive radiation pattern of the wings was found to depend on the time of application. Differences in radiation intensity were found to correspond to the red, blue and dark areas.  相似文献   

9.
Summary One of the products of the chromic acid oxidation of the animal triterpene ambreine (V) has been identified with the lactone C16H26O2 (III) whichRuzicka and coll. had isolated by oxidation of the plant diterpene sclareol (II). This identification confirms recent findings of the authors and ofRuzicka, Dürst andJeger and shows that the hydroxyle of ambreine (V) is at the same place as the hydroxyle of sclareol which is attached to the perhydronaphtalene ring.

4me communication sur les constituants de l'ambre gris  相似文献   

10.
Hydrogen sulfide (H2S) plays an important role in inflammation. We showed that macrophages expressed the H2S-forming enzyme cystathionine gamma-lyase (CSE) and produced H2S. Lipopolysaccharide (LPS) stimulated the CSE expression and H2S production rate. l-cysteine reduced LPS-induced nitric oxide (NO) production. CSE inhibitor blocked the inhibitory effect of l-cysteine. CSE knockdown increased, whereas CSE overexpression decreased LPS-induced NO production. Dexamethasone suppressed LPS-induced CSE expression and the H2S production rate as well as NO production. l-arginine increased, whereas NG-nitro-l-arginine methyl ester (l-NAME) decreased LPS-induced CSE expression and H2S production. Dexamethasone plus l-NAME significantly decreased LPS-induced CSE expression and H2S production compared to l-NAME. Our results suggest that macrophages are one of the H2S producing sources. H2S might exert anti-inflammatory effects by inhibiting NO production. Dexamethasone may directly inhibit CSE expression and H2S production, besides the NO-dependent way. Inhibition of H2S and NO production may be a mechanism by which glucocorticoids coordinate the balance between pro- and anti-inflammatory mediators during inflammation.  相似文献   

11.
Summary Corticotropin1–24 and [Gly1]corticotropin1–18 amide increased the fluorescence of 1-anilinonaphthalene-8-sulfonate which bound to the bovine adrenocortical membranes. The two ACTH fragments interacted with the protein of the membranes and increased the net positive charge of the membranes.We thank Prof. Dr.M. Kikuno for his stimulating criticism. This work was partly supported by a grant from Keio University School of Medicine.  相似文献   

12.
Summary Folic acid competitively inhibited brainl-glutamic decarboxylase (K i=1.62×10–3 M). This inhibition could possibly be associated with epilepsy.This work was supported by the United Parkinson Foundation.  相似文献   

13.
Résumé On a mesuré le taux de triiodothyronine et de thyroxine dans le plasma du veau nouveau né pendant ses premiers 11 jours. Le ratio d T3: T4 a eu son maximum au 5e jour.

Acknowledgements. This work was supported by the Medical Research Council. The triiodothyronine antiserum was kindly provided by Dr.R. D. Hesch.  相似文献   

14.
Summary Ser4-Glu(NH2)8-Oxytocin has been synthesized. The identity of the synthetic compound with the neurohypophysal hormone (Glumitocin) recently isolated from species of cartilaginous is demonstrated.

Über Peptidsynthesen XLIII. Mitteilung,E. Klieger, Experientia23, 620 (1967).  相似文献   

15.
Zusammenfassung Oxydation des (32P) Cyclophosphamides durch KMnO4 in Wasser oder Aceton führt zu 4-Ketocyclophosphamid und einem N-dechloroäthylierten Derivat des Cyclophosphamides, beides bekannte Metaboliten der Droge. Die Auftrennung der Produkte gelingt durch Dünnschichtchromatographie und die Richtigkeit der Strukturen wurde durch Massenspectrometrie nachgewiesen.

Acknowledgments. This investigation was supported by grants to the Chester Beatty Research Institute (Institute of Cancer Research: Royal Cancer Hospital) from the Medical Research Council and Cancer Research Campaign. The A.E.I. MS-12 mass spectrometer was purchased on a special grant No. G969/189/C from the Medical Research Council. The work was carried out partly during the tenure of a Ludwig Fellowship awarded by Cancer Research Institute. The interest of ProfessorA. B. Foster and Dr.T. A. Connors in this work, and the skilled technical assistance of Mr.M. H. Baker, are gratefully acknowledged.  相似文献   

16.
A major cytokinin found in coconut milk was isolted by using the tobacco callus growth-promoting assay as a guide during purification. The structure of the factor was determined to be 14-O-{3-O-[-d-galactopyranosyl-(12)--d--galactopyranosyl-(13)--L-arabinofuranosyl]-4-O-(-L-arabinofuranosyl)--d-galactopyranosyl}-trans-zeatin riboside [G3A2-ZR] by various NMR techniques, including heteronuclear multiple bond connectivity by 2D multiple quantum NMR (HMBC), as well as mass spectroscopy and sugar analysis. The optimum concentration of G3A2-ZR for cytokinin activity in the tobacco callus assay was estimated to be 5×10–6 M, so that G3A2-ZR is one order of magnitude more potent than 1,3-diphenylurea and one order less potent than zeatin riboside. At least 20% of the cytokinin activity of coconut milk could be attributed to G3A2-ZR.  相似文献   

17.
Zusammenfassung Die Zusammensetzung von in wässeriger Lösung gebildeten Ionenpaaren des Anions [W(CN)4(OH)4]4- mit Cr3+ bzw. Fe3+ wird amperometrisch ermittelt.

Acknowledgment. The authors are grateful to Dr.S. M. F. Rahman for providing necessary facilities and C.S.I.R. (India) for awarding a Junior Fellowship to one of them (K. U.).  相似文献   

18.
Zusammenfassung Mittels biochemischer Daten wird der Nachweis erbracht, dass im Ovidukt des Huhnes während der Schalenbildung zwar vermehrt NH4 + freigesetzt wird, jedoch eine negative Korrelation zwischen NH4 +-Produktion und Ca++-Abscheidung besteht.

Supported by a training grant from the U.S. Public Health Service No. 5-T1-DE-118. We thank Dr.P. R. Tramell for his help during the initial stage of this investigation.  相似文献   

19.
Riassunto Viene studiato lo sviluppo diPhallusia mammillata in acqua di mare priva di ioni SO 4 = . Le anomalie riscontrate a carico della larva riguardano principalmente il sistema muscolare della coda. Viene discusso il probabile ruolo esplicato dagli ioni SO 4 = nel corso dello sviluppo.

We are very much obliged to the Director, Dr.Peter Dohrn and to the staff of the Stazione for effective support and help in our work.  相似文献   

20.
Summary Glutamic acid does not, either in small or in large doses, inhibit the degeneration of the medullary sheath of peripheral nerves in rats, induced within 15 days by addition of 0.25% of isoniazid to their diet. The detoxicating effect of glutamic acid, as described byCedrangolo 1, thus only applies to the general toxic symptoms of the acute INH-intoxication, as is the case for vitamins B2, B12, A, E, K, and niacinamide.  相似文献   

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