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1.
Summary Urinary amino acids are converted into DNP-derivatives. Extraction by organic solvents yields both ether- and acid-soluble DNP-derivatives in a form suitable for separation and identification by thin-layer chromatography. Solvent systems and techniques for the detection of 35 urinary constituents are described. The method is applicable to the qualitative analysis of other biological fluids.  相似文献   

2.
Summary Amino acid separation with 6 different solvents on chromatoplates prepared from Kieselgel G (Merck) is described. As demonstrated in Figur 8 and discussed in the text, this technique is equal or superior to paper chromatography.  相似文献   

3.
Summary The amphidiploid hybrid ofNicotiana glauca ×N. langsdorffi, producing tumors spontaneously, contains essentially more of the following free amino acids than the inital species: cystine, histamine, oxyproline, alanine, kynurenine, tryptophane, and a non-identified ninhydrine positive substance. It is supposed that the abnormally high content of free amino acids is connected with the spontaneous formation of tumors.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

4.
Résumé Les sécrétions salivaires du Phylloxéra contiennent à un très haut degré de concentration les acides aminés suivants: la lysine, l'histidine et la tryptophane; deux autres acides aminés — vraisemblablement l'acide glutamique et la valine — s'y trouvent à l'état moins concentré. Ces substances appliquées expérimentalement sont capables de provoquer la formation des galles de la vigne tout aussi bien que les sécrétions naturelles du Phylloxéra. Pour cette raison, il semble suffisamment prouvé que ces substances sont identiques à l'agent cécidogène du Phylloxéra ou qu'elles représentent au moins sa composante la plus efficace.  相似文献   

5.
Summary The F1- and FnR-hybrids ofPlatypoecilus maculatus andXiphophorus helleri (Poeciliidae), producing melanomase spontaneously, contain essentially more free amino acids than the initial species. Further experiments show that the abnormally high content of free amino acids is connected with the spontaneous formation of tumors.

Den Herren Prof. Dr.G. de Lattin (Zoologisches Institut Saarbrücken) und Prof. Dr.B. Eistert (Institut für organische Chemie Saarbrücken) sind wir für die stete Förderung dieser Arbeit zu grösstem Dank verpflichtet. Den Herren Prof. Dr.C. Kosswig (Hamburg), Prof. Dr.M. Gordon (New York) und Dr.H. Breider (Würzburg) sind wir für viele Anregungen und die freundliche Überlassung von Zuchtstämmen sehr dankbar. — Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.

F. Anders, F. Vester, K. Klinke undH. Schumacher, Biol. Zbl., im Druck.  相似文献   

6.
Summary The chemical structure of the polyenoic fatty acids occuring in organ phosphatides and in fish oils is reviewed. The double bonds of all these polyenoic acids are arranged in divinylmethane pattern. Except some of the C16-polyenoic acids of fish oils, these polyenoic acids belong either to the oleic, linoleic or linolenic acid type and have chain lengths C18, C20, and C22. Polyenoic acids of the oleic acid type are present only in small amounts in phosphatides of mammalian origin. Fish oils are lacking in these but predominantly contain polyenoic acids of the linolenic acid type.Metabolic studies have shown that polyenoic acids of linoleic acid type (e.g. arachidonic acid) originate from linoleic acid and those of the linolenic acid type (e.g. C20-pentaenoic and C22-hexaenoic acid) from linolenic acid-both supplemented exogenous-by extension of the carbon chain by acetate on the side of the carboxylic acid group and introduction of additional double bonds in the divinylmethane pattern directed toward the carboxylic acid group. There is some evidence, however, that a total synthesis of the polyenoic acids of the oleic acid type occurs in the animal body.The transformation of linolenic to C22-hexaenoic acid and some intermediate reactans have been investigated more precisely by means of the tracer method. As far as the biosynthesis of the polyenoic fatty acids is concerned there are no fundamental differences in different vertebrates.

Nach einem Vortrag auf der gemeinsamen Tagung der deutschen, französischen und schweizerischen Biochemiker in Zürich vom 10.–12. Oktober 1960.  相似文献   

7.
Summary Sodium ribonucleinate and sodium desoxyribonucleinate increasesin vitro the phagocytosis of surviving rat's leucocytes. The average figure for the effect is greater than the limits of error, even in dilutions of 1:100,000. In dilutions of 1:10,000, the action is more striking, the results being 33% and 29% respectively above the control value.  相似文献   

8.
Summary The oxidation of succinic-, malic-, and -ketoglutaric acid by cauliflower mitochondria is slowed down by strong visible light. The cytochrome-c-oxidase activity is also inhibited by light and the pigment is completely reduced in time. It is concluded that the Krebscycle is inhibited by light.  相似文献   

9.
PTH-Aminosäuren     
Summary Methods for the identification of DNP-and PTH-amino acids are improved by application of thin-layer chromatography using Kieselgel G. The advantages over paperchromatography are better resolution, increased sensitivity and time-saving.  相似文献   

10.
Summary The incorporation of14C-amino acids into ribonucleoproteid particles obtained by differential centrifugation of mechanically disintegrated liver cell nuclei was demonstratedin vitro. Nuclear supernatant revealed also very remarkable incorporation.  相似文献   

11.
12.
Summary Spontaneous transulfuration reactions between alaninethiosulfonic acid and hypotaurine, and between thiotaurine and cysteinesulfinic acid, have been demonstrated.  相似文献   

13.
Summary Two possible objections against the diffusion theory of water permeability in protoplasm1 are discussed. One is refuted, while the other is valid. But it causes no change of the formula which has been derived for the calculation of water permeation constants strictly comparable to the constants of permeating osmotica.  相似文献   

14.
Summary Methanolysis of podophyllotoxin (I) with ZnCl2 as catalyst yields podophyllinic acid methyl ester (IV) and neopodophyllotoxin (V), a new isomer of podophyllotoxin. Neopodophyllotoxin which contains the lactone group in the 1,3-position is stereospecifically hydrolyzed by alkali to the hitherto unknown podophyllinic acid (VI).

12. Mitteilung über mitosehemmende Naturstoffe.  相似文献   

15.
Summary The proportion of purines and pyrimidines in the DNA of the Ehrlich mouse ascites carcinoma is examined and compared with the base proportion of the DNA from liver and kidney of the normal mouse. The following findings were obtained: The DNA of the ascites tumor contains more guanine and less cytosine and thymine than the DNA of the normal mouse. For guanine this difference is statistically significant. The changed base compound is discussed with regard to the changed growing rate in tumors and the altered chromosome structure in the Ehrlich ascites carcinoma.

Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   

16.
Summary Following intravenous injection of pyruvic acid (PA) in the form of the sodium salt in the normal rabbit the level of PA in the blood rises, falling again to the initial level after 60 minutes. In the case of the alloxandiabetic animal the elimination of PA administered in equal doses is markedly retarded. If animals are used that suffer from a progredient alloxan diabetes leading to death in coma, an increased endogenous hyperpyruviæmia can be demonstrated. Insulin plays no part in the regulation of PA metabolism; through the application of aneurin, however, one succeeds in enabling the organism to make use of PA. A separate report will deal with the complex relations holding in endogenous hyperpyruviæmia in coma.

Der Großteil der Experimente wurde mit Unterstützung der Roche-Studienstiftung durchgeführt.  相似文献   

17.
Summary In the end-stage of progressive alloxan diabetes of the rabbit we have been able to overcome the acute pyruvic acidosis by the use of phosphorylated vitamin B1 (cocarboxylase) together with vitamin B2, while it is impossible to cure the endogen hyperpyruviæmia with simple vitamin B1. The superiority of the coferment over the vitamin, which is only effective at the beginning of the decompensation, implies the existence of a disturbance in the phosphorylation during the crisis of diabetic metabolism. We have been successful in preventing the inevitable death in coma of diabetic rabbits by doses of cocarboxylase + riboflavin, and we were able to keep them alive by continuous doses of insulin together with vitamin B1 and B2.

Ein Teil der Experimente wurde mit Unterstützung der Roche-Studienstiftung durchgeführt.  相似文献   

18.
Summary Gliadin and chymotrypsinogen, respectively, were treated with alkaline sodium hypochlorite solution equivalent to the carbonamide groups present, and then hydrolysed by acid. The proteins treated with dilute alkaline solution have been assayed in control experiments for their content of N-terminal amino acids. The degradation products identified by paper chromatography seem to indicate that in chymotrypsinogen the amido groups of the amino dicarboxylic acids represent asparaginyl (Ia) and glutaminyl (Ib) residues. In gliadin, besides these residues, the presence of isoglutaminyl residues (IVb) also seems to be probable.  相似文献   

19.
Summary In isolated shoots ofCentaurea jacea, placed in a solution of 0.5% glutamic acid for 15 h, the concentration of free amino acids in the stems is more than doubled. Compared with the controls, these shoots with an increased amino acid concentration are preferred by aphids in the preference-test.  相似文献   

20.
Summary The capacity of binding copper ions of several aminoacids and peptides has been investigated. A direct colorimetric method measuring comparable values of bound Cu2+ has been developed.

37. Mitteilung; 36. Mitteilung:R. Gall undH. Erlenmeyer, Helv. chim. Acta38, 1421 (1955).  相似文献   

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