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Summary The effects of two compounds with sulfonic acid groups, chlorazol sky blue and Germanin (Bayer 205), are being studied on the developing egg of the sea urchin,Paracentrotus lividus. The chlorazol sky blue (1/5000) is a very effective animalizing agent. In dilute solutions (1/25000 and 1/100000), it induces the development of radial larvae. The lithium chloride counteracts the animalizing effects of chlorazol sky blue. The Germanin has an animalizing effect only at high concentrations. The penetration of these agents appears essential for the animalization. The reaction of the sulfonic acid groups with the basic groups of the intracellular proteins appears to be concerned with the animalizing effect. The results of these experiments are discussed in relation to the animalizing effects of various sulfonated dyes and zinc ions.  相似文献   

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Summary The proteinic material corresponding toDubuisson's electrophoretic gradient has been prepared by a new method. This fraction migrates as a single peak in the U-tube, but is heterogeneous in the ultra-centrifugation.  相似文献   

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Zusammenfassung In vitro gezüchtete Zellen des Rous'schen Sarkoms wurden der Wirkung von Röntgenstrahlen und radioaktivem Alkohol (CH3C14H2OH) ausgesetzt und darauf elektronenoptisch untersucht. In einem geringen Prozentsatz der untersuchten Kulturen (9,5%) konnten virusartige Partikelchen von 60 bis 90 mµ Durchmesser intra- oder extrazellulär dargestellt werden, die mit den vonClaude, Porter undPickels gefundenen identisch sind und wahrscheinlich dem Rousschen Virus zugeordnet werden können. Es wurden Kolonien von solchen Gebilden intrazytoplasmatisch in Form von Einschlusskörperchen beobachtet. Auch unbestrahlte Kontrollen von Sarkomzellen wiesen Viruskörperchen auf, wenn auch bisher in geringerem Prozentsatz.Es ist vorderhand noch unsicher, ob der Bestrahlung eine primäre Rolle in der Darstellbarkeit dieser Viren zukommt.  相似文献   

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Summary By a quantitative study of pleochroic haloes in biotite, the haloe age of the Lausitz granodiorite, in comparison with the granite age of the Elba Isle, was estimated to 280±150 M.Y. The granodiorite is either caledonian or hercynian.

Attachée à l'Institut Interuniversitaire des Sciences Nucléaires.  相似文献   

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Summary The author deals with the errors occurring in microphotometric measurements and their correction. Even in measurements for comparative purposes, they are inavoidable.  相似文献   

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Riassunto Sono stati studiati gli aloni dei graniti delle isole di Montecristo e del Giglio (arcipelago toscano) e del continente (Gavorrano).Tale studio ha permesso di dimostrare che il loro consolidamento è avvenuto in momenti diversi la cui successione ripete quella dei corrugamenti appenninici. Le età di tali graniti, comparate a quella dell'Elba (Monte Capanne), sono nel seguente ordine:Elba = Montecristo > Giglio > Gavorrano.I singoli stadi sono largamente spaziati nel tempo e gli intervalli sono risultati dell'ordine di circa dieci millioni di anni.

Attachée à l'Institut Interuniversitaire des Sciences Nucléaires.

Comitato Nazionale per le Ricerche Nucleari.  相似文献   

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Summary 2, 4-dichlorophenol (DCP), 2, 4-dinitrophenol (DNP) and 2, 4-dinitro-o-cresol (DNC) applied at a concentration of 1.10–7 to 1.10–3 M, produce a dramatic increase in IAA-oxidase activity in young cells ofLens root. IAA destruction by breis from root tissues was inhibited by Mn++ ion at low concentrations of DCP (1·10 to 1.10–7 M), but was enhanced by Mn++ ion at higher (1.10–5 to 1.10–3 M) DCP levels.

Ce travail a pu être entreprise grâce à l'appui duFonds national suisse pour la Recherche scientifique.  相似文献   

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Summary An apparatus has been described for measuring oxygen consumption in small animals. In this apparatus, the temperature changes are very small, the determinations of oxygen consumption are rapid and frequent, the oxygen tension is normal and the animals are in a good state of quietness.  相似文献   

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Summary The 21-sulfates of the six following corticosteroids: desoxycorticosterone (DOC), corticosterone (B), 11-dehydrocorticosterone (A), cortisol (F), cortisone (E), and 17 hydroxy-11-desoxycorticosterone (S), were prepared. Their separation by four different paper chromatographic systems was investigated. A method for detection of the spots is described.  相似文献   

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Summary A cytochemical study of the distribution of sulfhydryl groups in animalized and vegetalized embryos of the sea-urchinParacentrotus lividus has been made by use of the Bennett's reagent. The distribution of the sulfhydryl groups appears homogeneous in these embryos. No gradient has been observed in the experimental conditions used.  相似文献   

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Zusammenfassung Die Differenzierung der Dunen des Hühnerembryos lässt drei Phasen erkennen: 1. Eine der Haut fremde Anregung löst im Corium die Bildung der Dunenanlagen aus; 2. diese Dunenanlagen üben eine kurzfristige induzierende Wirkung aus, die die Epidermis zur Ausbuchtung der Dunen veranlasst; 3. die auswachsende Dunenepidermis kommt dann selber zur Induktionsaktivität und bewirkt das Eindringen der Coriumzellen in den in die Länge wachsenden Epidermiszylinder.  相似文献   

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Summary The radiations coming from Blanc Brillant de Luxe' fluorescent stimulate the growth and ramification of protonema ofCeratodon purpureus (Hedw.) Brid. This stimulation is caused by red light (660 nm). Multidirectional lightening is more favorable than unidirectional exposition.  相似文献   

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Summary In intact guinea-pigs fed with glucose solutions of different concentrations, the main limiting factor of absorption is not the gastric emptying but the hyperglycaemia.  相似文献   

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Summary The action of various proteolytic and glucidolytic enzymes on the biological potency of Human Menopausal Gonadotropin was studied. Trypsin, chymotrypsin, papaïn and glucosidase attack the gonadotropin only after 6 h of digestion. Carboxypeptidase and RDE produce a rapid inactivation.  相似文献   

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Summary A series ofin vitro experiments have been made on lactic acid production in anaerobiosis in the developing optic lobes (mesencephalon) of the chick embryo. The rate of anaerobic glycolysis is relatively important during multiplication of the neuroblasts; but, during the differentiation of the neuroblasts into mature neurons, the anaerobic processes are lower than the phosphorylation and oxidation mechanisms essential for the growth of nerve expansions and onset of functional activity.  相似文献   

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Zusammenfassung Hydratisiertes Phosphoroxychlorid besteht aus zyklischen und langkettigen Polyphosphorsäure-Chloriden, die nicht beständig sind und leicht hydrolysiert werden. Hydratisiertes Phosphoroxychlorid erlaubt die Synthese von langkettigen Thiaminpolyphosphorsäureestern, die mehr als drei Phosphorsäure-Reste je Molekül enthalten.  相似文献   

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