Über den Intermediär-Stoffwechsel vonAspergillus niger

Summary Oxalic acid is only dissimilated if other carbon sources are present (e.g. citric acid, succinic acid), whereas malonic acid is also dissimilated as a single component byA. niger. It is supposed that the latter is used by the mould not only energetically but also for building up cell substance.     

Über die Basizität der Knochenmineralien

Summary The inorganic salts of bone tissue are, owing mainly to their contents of tertiary phosphate, strongly basic. A quantitative evaluation of these base equivalents can be performed through simple titration with acid after solution of the bone salts in a chelating agent (e.g. citrate). Referring to an endpoint of pH 7.40, one finds that per mMol Calcium 0.82 mEq base is set free. With regard to acid-base metabolism, the results indicate that bone phosphate, whichin vivo can be mobilised through osteoclastic resorption, forms a remarkably big base reserve in the animal organism.

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Die vorliegende Arbeit wurde mit der Unterstützung des Schweiz. Nationalfonds zur Förderung der wissenschaftlichen Forschung durchgeführt.     

Über die Basizität der Knochenmineralien

Summary Interpretations regarding the structure of the bone mineral, based on quantitative data as to the basicity of calcium phosphate, have been complemented by X-ray and electron microscopic investigations. The chemical nature of the bone material is thereby thought to be substituted apatite.

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Ergänzende Bemerkungen zur Arbeit vonJ. Raaflaub, Exper.17, 443 (1961).     

Über die antithyreotoxische Wirkung der Pantothensäure

Summary Administration of calcium pantothenate to white rats in daily doses of 50–100 mg improved the signs of experimental thyreotoxicosis and decreased the metabolic rate.     

Über die Herkunft der Isovaleriansäure im Magnamycin

Summary L-Leucine is the precursor of the isovaleric acid in magnamycin, as could be demonstrated withL-Leucine-[U-¹⁴].

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IX. Mitt. Zur Biogenese der Makrolide. VIII. Mitt.W. Hofheinz, H. Grisebach undH. Friebolin, Tetrahedron, im Druck.     

Über die Aktivität der Tyrosinase in Tabaksamen

Summary Water or buffered extracts from tobacco seeds (Mont Calme brun) showed both cresolase and catecholase activity of tyrosinase, which was inhibited by 10^–2 M thiourea. No difference of activity could be observed in extracts from old and fresh seeds. Unexpectedly, chlorogenic acid is not oxidized by this tyrosinase.     

Über die Wirkungsweise der Katalasen

Ohne ZusammenfassungHauptreferat, gehalten vor der Schweizerischen Medizinisch-Biologischen Gesellschaft in Genf am 31. August 1947, anläßlich der 127. Generalversammlung der Schweizerischen Naturforschenden Gesellschaft.     

Über die Rolle der Stabilitätsbetrachtungen in der Entwicklung der Bohrschen Atomtheorie

Ohne Zusammenfassung Vorgelegt von L. Rosenfeld     

Über die Abhängigkeit der photodynamischen Wirkung von der Intensität der UV.-Bestrahlung

Summary (1) The relation between photodynamic effect and intensity of ultra-violet radiation was investigated by means of the lethal-curve of yeast cells treated with benzpyrene as photosensibilizer.(2) If the dosis of radiation ist kept constant, the resulting photodynamic effect decreases rapidly with diminishing intensity.

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Teilergebnisse der Dissertation.     

Über die optimale Zusammensetzung der Nahrung

Résumé La notion d'«alimentation optimale», préconisée parMacCollum, est soumise à une critique au cours de laquelle l'auteur montre les difficultés qui se présentent lorsque l'on veut préciser cette notion. Il relève le rôle encore peu clair que joue la flore intestinale pour la synthèse de substances essentielles à l'alimentation de l'homme. La quantité optimale nécessaire n'est en matière d'alimentation pas une valeur stable, car elle dépend de la situation générale du métabolisme, ainsi que le prouvent certains exemples de la physiologie des vitamines B.Une méthode particulièrement adéquate, spécifique pour reconnaître une situation optimale de l'alimentation, est donnée dans la méthode d'autosélection («self selection»), plus spécialement sous la forme développée parC. P. Richter. On peut trouver bien des analogies entre les résultats expérimentaux et certains faits connus de l'alimentation humaine. En ce qui concerne le régime optimal pour l'homme, seules les expériences sur l'homme sont déterminantes, comme elles ont été entreprises aux Etats-Unis au cours de la dernière guerre chez des volontaires.Les recherches expérimentales sur l'effet que les vitamines et d'autres substances alimentaires déterminent sur le développement des infections et des tumeurs malignes montrent qu'au régime alimentaire suboptimal et optimal s'oppose le régime superoptimal.

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Vortrag, gehalten am 23. Oktober 1946 in der Naturforschenden Gesellschaft in Basel.     

Über die Funktion der Lorenzinischen Ampullen der Selachier

Summary The afferent impulses from the ampullae ofLorenzini ofScyllium show, both in the intact animal and in the isolated preparation, a steady discharge at constant temperature with a frequency reaching a maximum at an average of 20° and decreasing continuously at higher and lower temperatures. The discharge stops between 5° and 30° on the average. Rapid cooling causes a temporary rise in frequency, while rapid warming causes a temporary drop in frequency. While the ampullae are not sensitive to a mechanical stimulus, they react definitely to a change in temperature of 0.05°C. The ampullae thus behave like the cold receptors of the homoiotherms.     

Über die Temperaturabhängigkeit der Galvanonarkose bei Fröschen

Summary The relation of the threshold current dose to the temperature constitutes a function of the chain-line type (hyperbolic function).From the dependence of the recovery time after galvanonarcosis upon the temperature it is concluded that by the passage of direct current molecular arrangements on surfaces are reversibly disturbed.     

Über Ester der Polygalakturonsäure

Summary Polygalacturonic acids (pectic acids) can easily be esterified by epoxides (ethylene oxide, 2,3-epoxy-1-propanol, epichlorhydrin, etc.) in the presence of water. Under favorable conditions the degradation of the macromolecules is negligible. Some properties of the glycol esters of polygalacturonic acid which are similar to those of the methyl esters of polygalacturonic acid (pectinic acids) are described. The glycol and glycerol esters, however, are not saponified by the enzyme pectase. These compounds react much more rapidly with formaldehyde than pectinic acid which does not possess primary hydroxyl groups.     

Über die «absoluten» Bewegungen der Milchstrasse und der nächsten Spiralnebel

Summary (1) The milky way is moving absolutely (relative to the light-ether) with a velocity of at least 600 km/s in the direction of the absolute movement of the earth (A=78°,D=+40°).(2) The point of symmetry of the absolute velocities of the spirals is situated about 1,120,000 parsec from the milky way in the direction of the antapex of his absolute movement, and it has taken 1·83 milliards of years for the milky way to cross this distance.(3) Probably the next spirals are forming with the milky way as a center a group with a common parallel movement like that one of the milky way.     

Über die Wasserdurchlässigkeit von Hydrogelen

Summary The permeability of different jellies is measured under various conditions. This property may be of value for the structural analysis of these systems.     

Über die Fettsäuren aus Spinatchloroplasten

Summary The fatty acids of two samples of chloroplasts fromSpinacia oleracea have been investigated quantitatively. They contain many polyenoic fatty acids (more than 70% of the total fatty acids); amongst these, a relatively high content of C¹⁶-trienoic acid is remarkable. Moreover, the presence of the ³-trans-hexadecenoic acid, recently detected in plants, is noteworthy.