Die Zucht vonLytta vesicatoria im Laboratorium und Nachweis der Cantharidinsynthese in Larven

Summary Adult males ofLytta vesicatoria (Coleopt., Meloidae) synthesize cantharidin, but females do not, although the substance is present in the females too. We developed a method for rearing larvae of this parasitic beetle in the laboratory. It is shown that there exist 7 larval stages and 4 hypermetamorphic forms (triungulinus, second larva,pseudochrysalis and fourth larva). Larvae from the second to the fifth stage (second larva) synthesize cantharidin. Therefore, we conclude that the substance present in the adult female is at least in part synthesized in the larval period. Nothing is known about the biological significance of this biochemical sexual dimorphism.

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Coleoptera, Meloidae.     

Disparolone,a novel tumor inhibitor derived from the gypsy mothPortheria dispar (L.)

Zusammenfassung Disparolon, als neue tumorhemmende Verbindung von Weibchen des Schwammspinners,Porthetria dispar L., wurde isoliert und als 7-Oxohexadec-cis-10-enol-(1) identifiziert und synthetisch dargestellt. Die Verbindung ist gegen Walker Karzinosarkom 256 in Ratten aktiv.     

Parthenogenetic reptiles: New subjects for laboratory research

Summary Problems preventing establishment of laboratory colonies of parthenogenetic lizards have been solved. Now, productive colonies of these lizards, which have remarkably little genetic variation, can be readily established and used not only for research on parthenogenesis but also for many kinds of experiments for which reptile systems are desirable. Research colonies can provide valuable specimens while reducing the exploitation of natural populations.We thank José P. O. Rosado and George W. Foley for technical assistance and Richard G. Zweifel for specimens, ideas and support.     

磁处理对粘土在水和药剂水溶液中膨胀的影响

本文用Ensulin法和Tl法研究了磁处理对粘土膨胀的影响,证实了磁处理对粘土膨胀的抑制作用,其中包括磁处理对粘土在水中和阴离子、非离子活性剂水溶液中膨胀的抑制作用和对无机盐、阳离子活性剂、无机和有机阳离子聚合物等防膨剂的增效作用。研究表明,不同的磁感应强度对粘土防膨效果有不同的影响,不同体系有不同的最佳磁感应强度,但一般在60～200mT的范围。     

Direct histochemical demonstration of histamine in cutaneous mast cells: Urticaria pigmentosa and keloids

Zusammenfassung Die Haut von Patienten mit Urticaria pigmentosa und Keloiden wurde mit der histochemischeno-Phthaldialdehyd-Technik untersucht. Die Lokalisation von Histamin konnte durch Fluoreszenzmikroskopie festgestellt werden.     

Effects of stimulation and inhibition of bicarbonate reabsorption on the renal tubular transport of sodium and chloride in the dog

Résumé L'acidose respiratoire aiguë n'affecte pas significativement la réabsorption tubulaire du Na et du Cl, alors que celle-ci est déprimée par l'administration d'acétazolamide.     

Zur Bestimmung der Katalaseaktivität in Bodenproben

Summary Two methods for the determination of catalase activity in soil samples are described.