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1.
Zusammenfassung Laboratoriumsexperimente mit Phosphamidon ergeben eine günstige kritische Dosisempfindlichkeit für Labeo-Karpfen (150–250 ppm). Es gelingt so leicht, Wasserinsekten (2–10 ppm) und Raubfischstadien (20–125 ppm) aus den Frischwasserreservoiren zu eliminieren.

Prepared and sold under the name of Dimecron 100 by Ciba Basel, (Switzerland).  相似文献   

2.
Summary The quantity of phyto-estrogens in red clover, hop, peas, and cabbage was estimated by titration on castrated female rats and infantile mice. The level of phytoestrogens was as follows: in hop 1050–2000/kg, in peas 4–6/kg, in cabbage 24/kg, and in red clover 6–9/kg. The author supposes that the sexual disorders described byRosenberger 14 in cows fed with cabbage, can be explained by the presence of phyto-estrogens in this plant.  相似文献   

3.
Summary (1) A response ofZea mays andPisum roots cultured aseptically to 2,4-dichlorophenoxyacetic acid has been observed.Depending on the concentrationZea mays shows an increase of the growth rate (optimal concentration 10–11 mol) which turns over to an inhibition (above 10–7 mol). The curve is similar to that obtained by 3-indoleacetic acid, which proves the phytohormonal character of 2,4-D.(2) ThePisum root is more sensitive than theZea mays root. A concentration of 10–7 molinhibitsPisum in a high degree, whileZea mays is no more inhibited, thus demonstrating the selective herbicidal action of 2,4-D against isolated roots of Dicotyledons culturedin vitro.  相似文献   

4.
Summary If the complete rate equations for reversible, one-step, bimolecular reactions are written withP eP as the concentration variable (whereP e is the equilibrium, andP is the instantaneous, product concentration), the 3 possible stoichiometries can be reduced to a single straightforward differential equation. This can be solved very economically. For each stoichiometry, weret is time,k 1 is the forward rate constant,K e is the equilibrium constant, and P isPP o. The termsP cP o andD+P cP o are the physically possible and physically impossible roots of the quadratic equation forP eP o in terms of the initial concentrations andK c.D is the discriminant in this equation. All 3 quantities can be calculated if the equilibrium constant is known. A plot oft against ln{[1–P/(D+P cP o)]/[1–P/(P cP o)]} should be a straight line for any second order reaction. For each stoichiometry,P cP o approachesA o, the initial concentration of the first reactant, as the equilibrium constant increases. When a second reactant is present,D+P eP o approachesB o. The limiting equation is then that of an irreversible bimolecular reaction. For AP+Q,D approaches –K e as the equilibrium constant becomes large, and the value of the second logarithmic term in the integrated equation approaches zero. The limiting equation is that of an irreversible, unimolecular reaction.Acknowledgments. I thank Dr. Athel Cornish-Bowden for many helpful discussions. This work was partially supported by a grant from Utah State University.  相似文献   

5.
Summary Studies conducted onCercis siliquastrum seeds treated with kinetin confirm that this hormone does not interrupt dormancy in either whole seeds or those decoated at the radical pole. Seeds totally decoated or decoated at the cotyledon pole only demonstrated atypical germinations linked to cotyledon growth, permitting the embryo to escape the inhibitory action present in the endosperm; this does not occur when the cotyledon surface is experimentally reduced.This investigation was supported by the Italian National Research Council (C.N.R.) Project Biology of Reproduction.  相似文献   

6.
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   

7.
Summary A new synthesis is described of a crystalline 7-methyl-doisynolic acid showing a strong estrogenic activity. This acid is probably identical with the stereoisomer C ofAnner andMiescher. Demethylation of this methoxyacid yields a new doisynolic acid of mp. 113–117° (hemihydrate).

XIII. MitteilungSynthetische Versuche in der Gruppe der östrogenen Hormone; XII. Mitteilung siehe Chem. listy50, 2004 (1956).  相似文献   

8.
Zusammenfassung Es wird gezeigt, dass 3–5-cAMP (10–3 M) und Theophyllin (10–4 M) die Permeabilität derjenigen Lysosmen-Membranen steigern, die aus Rattenleberzellen in bezug auf saure Phosphatase and in bezug auf -Glucuronidase-Enzyme präpariert wurden.  相似文献   

9.
    
Zusammenfassung Die Wirkung von Succinylcholin auf die-Fasern an unanästhesierten spinalen Katzen wurde analysiert: (1) 2–5 antidrome Entladungen einer Frequenz 100–300/sec bei einer elektrischen Einzelreizung; (2) antidrome, repetierende Entladungen ohne elektrische Reizung; (3) Blockierung der-Impulse folgte während 5–15 min den antidromen Entladungen.  相似文献   

10.
Summary Of several quaternary ammonium derivatives tested, 1-allyl-1-(3,7-dimethyloctyl)piperidinium bromide showed the best growth-retarding activity. OnChrysanthemum morifolium the growth retardation obtained with a single application of 100–200 ppm compared favourably with that obtained from 2–3 applications of 3400 ppm of N-dimethylaminosuccinamic acid (daminozide).  相似文献   

11.
Zusammenfassung Die Epidermiszellen von mit Mais-Mosaik-Virus infizierten Maisblättern enthalten runde oder längliche Einschlusskörper, welche meist dem Kern anhaften oder nahe bei diesem liegen. Sie erscheinen nach Giemsa-Färbung rosa bis purpurn gefärbt. Die Abmessungen der länglichen Einschlüsse betragen 3,0–4,6 · 14–26, der Durchmesser der rundlichen 2,0–7,7.  相似文献   

12.
Summary The incorporation of leucice-14C into protein in bovine mesenteric arteries was augmented by cyclic GMP (10–3 M) and decreased by cyclic AMP (10–3 M). There was no effect of 5 AMP (10–3 M). The phosphodiesterase inhibiting drugs theophylline (10–3 M) and papaverine (5×10–5 g/ml) both decreased the leucine-14C incorporation.We are indebted to Mrs.Lena Burlin for hear assistance. Finacial support has been provided by the Swedish State Medical Research Council (No. 04X-101X-4498).  相似文献   

13.
Résumé L'enzyme glutamate décarboxylase se trouve dans les extraits d'eau de l'aleurone de l'orge. Au début de la germination, l'activité de cette enzyme augmente, mais après, quand apparait l'enzyme -amylase, elle diminue. Quoiqu'au dessous d'une concentration de 2×10–6 M l'acide -amino butyrique (GABA) n'affecte pas l'activité de l'-amylase in vitro, la GABA à 5×10–6 M peut provoquer une inhibition de 25% qui n'est pas modifiée par des concentrations de GABA comprises entre 5×10–6 M et 10–3 M.  相似文献   

14.
Enterocytes isolated from rat jejunum were tested for the existence of a Cl/HCO 3 exchange, previously evidenced in basolateral membrane vesicles but not in brush border. Cells were found to retain functional integrity and transport capabilities long enough to allow Cl fluxes to be measured. Both efflux and uptake experiments indicate that a Cl/HCO 3 antiport, inhibited by 4,4-diisothiocyanostilbene-2-2-disulfonic acid (DIDS), is functional under resting conditions.  相似文献   

15.
Zusammenfassung Die Isolierung, Charakterisierung und antibiotischen Eigenschaften von-Guttiferin (I), C33H38O8 (Smp. 113–115°), aus den Samenhülsen und vom nahe verwandten-Guttiferin (II), C29H36O6 oder C33–34H38–40O8 (Smp. 86–91°) (möglicherweise identisch mit-Gambogasäure), aus Gummigutt, dem harzigen Sekret vonGarcinia morella, wurden beschrieben und ihre Verwandtschaft zu Morellin und Moreollin, den beiden bekannten Pigmenten der Samenhülsen, dargelegt. Für I wurde eine Partialstruktur vorgeschlagen. Die Bildung derselben komplexen bromhaltigen Säure vom Smp. 199 bis 200° unter der Einwirkung von Natriumhypobromit auf I und II spricht ferner für deren nahe strukturelle Verwandtschaft.  相似文献   

16.
Zusammenfassung Die somatische Muskulatur vonAscaris lumbricoides wird durch-Aminobuttersäure in Konzentrationen von 10–6-10–5 M völlig gehemmt. Eine hnliche Hemmung wird durch Piperazin (10–3 M) erzielt. Beide Substanzen steigern die Cl-Permeabilität der Muskelmembran.

On leave of absence from the Instituto de Biofísica, Universidade do Brazil, Rio de Janeiro (Brazil).  相似文献   

17.
Résumé Nous avons étudié l'adsorption négative des anions I*O 3 et Cr*O 4 –– à différents bentonites en fonction d'électrolytes additionnés. Pour les électrolytes NaCl et Na2SO4 les résultats sont en bon accord avec ceux deSchofield etMattson; nous avons étudié aussi l'effet de l'addition de solutions de CaCl2; celles-ci produisent le même effet à des dilutions 20 fois plus grandes que les solutions de NaCl. Comme ceci ne peut pas être expliqué sur la base de la théorie deDebye-Hückel, nous avons appliqué la théorie exacte de la couche double; le facteur 20 mentionné plus haut mène à une valeur de=–75 mV. En introduisant cette valeur de, une représentation graphiques–1/c pour les résultats des expériences au Na-bentonite + solutions de NaCl, donne une surface spécifique de 1110 m2/g.  相似文献   

18.
Zusammenfassung Es werden die Kennzeichen der Chromosomen vonRhinophylla fischeri, R. pumilio undCarollia castanea beschrieben. Für die GattungCarollia ist bei niedriger Diploidzahl (21 , 20 ) eine niedrige « nombre fondamental » (34–36) charakteristisch. Für die GattungRhinophylla wird eine grössere Diploidzahl (34–36) und eine grössere « nombre fondamental » (56–62) gefunden.

We thank Dr.C. J. Marinkelle andA. Cadena of the Universidad de Los Andes for assistance and facilities.Pvt. Genaro Lopez assisted with the field work. Dr.R. Strandtmann translated the summary. Supported by National Science Foundation Grant No. GB-8120.  相似文献   

19.
Summary A new synthetic phenyl-ethyl-amine derivative, the 2-[N- (3, 4-methylen-dioxyphenylethyl)-methylaminomethyl]-tetrahydrofuran, No. 11 081, exhibits a strong protective effect against cardiac fibrillation and arrhythmias produced by various experimental methods: against fibrillation due to aconitine 3 × 10–8 on the isolated cat's heart, it is active in a concentration of 10–6–2 × 10–6. Against cardiac arrhythmias produced in the cat by adrenaline + CHCl3 or cyclopropane, it shows a protective effect by 5–10 mg/kg i.v. and even perorally by 50 mg/kg. In these tests, the antifibrillatory activity of the new compound seems to be roughly the same as that of -fagarine, and higher than that of procaine.

9e communication sur les dérivés des alcoylène-imines; 8e communication, cf. Exper.10, 261 (1954).  相似文献   

20.
Résumé Nous avons observé que le iodoacétate en concentrations de 1·10–4, 5 · 10–5 et 1 · 10–5 M et préalablement incubé à 37 °C, a une influence de l'ordre de 61, 50 et 44% respectivement sur la totalité du pouvoir antigénique de l'insuline de buf. L'effet inhibitif est proportionnel à la durée d'incubation et l'on ne constate pas de différences lorsque les concentrations de l'hormone se trouvent entre 100 et 300U/ml.  相似文献   

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