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1.
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   

2.
Summary Acetophenone derivatives with a cortisone-like side chain have been investigated for their catalytic effect on the autoxydation of linolenic acid.-Hydroxy-acetophenone and the substituted-hydroxy-3,4-dimethoxyacetophenone are the substances with the simplest structure having a catalytic effect quantitatively and qualitatively similar to that of cortisone.The significance of substituents in the ring for the catalytic activity of the side chain is discussed.  相似文献   

3.
Summary The solubilities and other properties of compounds made by combination of optically active components, e.g. the solubilities of the salts made from the dextro-form of an acid and the dextro- or the laevo-form of a base are in some instancesextremely different. It is a consequence of these differences that in a living organism, containing optically active substance,the degree of optical purity of these substances is of outmost importance. The presence of undesired antipodes of any kind might fundamentally disturb the metabolism. It is also known that living organisms at least partly and continuously produce the optically active substances needed bysynthesis from optically inactive material.A kinetical and thermodynamical study of the conditions under which optically active substances can, with use of optically active catalysers, be synthetized from inactive material, shows that the degree of optical purity of the material synthetized is, even under the most favorable conditions, maximum in the beginning of the synthesis andis bound to decay when the synthesis is, chemically speaking,completed and if the synthetized material is left in contact with the catalyzer. Thus a racemization of the synthetized active material occurs in which the catalyzer which has originally produced this active substance actively accelerates the deterioration of its state of optical purity.The means are discussed by which the organism is able to delay this loss of optical purity; and it is shown that all poosible means to do so are indeed used by the organism. As these means can delay but never completely avoid the decay of optical purity, this decay, even if it be slow, i.e.an ageing of optical purity, is a necessity in the course of the life of a living organism. As a loss of optical purity must disturb the normal metabolism, this must, even if no other events occur, limit the individual life.Experimental evidence which would check the prediction of decay of optical purity with age is incomplete; in several instances, however, the experimental technique permits us to detect and to follow the occurrence of finite small amounts of undesired antipodes, e.g. of some amino acids in the proteins of living organisms.

Vortrag, gehalten vor der Schweizerischen Gerontologischen Gesellschaft in Basel am 11. Dezember 1954.  相似文献   

4.
5.
Summary A simple method for paper-electrochromatography of free aminoacids of blood serum is given. In the first direction of the separation a normal apparatus for paper electrophoresis of serum proteins at low voltage is used. The aminoacids are separated into neutral, acid and basic components according to their mobility in the electric field, and are separated in the second direction by means of the descending technique on a chromatogram sewn to the electropherogram.  相似文献   

6.
Summary Transverse osteotomies of the radius of dogs could be set and perfectly stabilized by means of pressure osteosyntheses. The primary healing process, observed radiologically, corresponds to the histological development of new osteons which, in completely opposed fragments, pass through the fracture and develop from the intact blood vessels and cells of the Haversian canals.  相似文献   

7.
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   

8.
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   

9.
Summary Using series of different reactions it has been possible to demonstrate that the tricarboxylic acid arising from anthranilic acid and pyruvic acid has not the constitution I but is correctly represented by IV. Several derivatives of this tricarboxylic acid were shown to have formulae that are in sharp contrast to those found in literature.  相似文献   

10.
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   

11.
Summary The mechanism of incorporation of different mental ions into phthalocyaninetetrasulfonic acid in aqueous solution has been investigated. It was found that the rate of the reacion with Cu2+ depends on the dissociation rate of the N-H-bond of this porphyrin-like chelating agent, whereas the reaction rate with other metal ions, like Zn2+, does not.

II. Mitt. Siehe I. Mitt.:K. Bernauer undS. Fallab, Helv.44, 1287 (1961).

Herrn Prof. Dr.H. Erlenmeyer sind wir für sein reges Interesse an dieser Arbeit zu bestem Dank verpflichtet.  相似文献   

12.
Summary The results are reported of investigations on the content of neuraminic acid in serum of 15 animal species, pure serum protein fractions, fibrin, haemoglobin, urine, liquor, saliva and milk.  相似文献   

13.
Summary The hyperplasia and hyperaemia of the thyreoidea of rats caused by thiouracil treatment can be largely avoided by simultaneous doses of vitamin-A methylether.  相似文献   

14.
Summary Acetoin and 2, 3-butylene glycol in blood of renal and hepatic patients are raised, when consciousness is disturbed. There is no correlation between blood levels of acetoin and 2, 3-butylene glycol and the degree of impairment of consciousness. Simultaneous determinations of acetoin and 2, 3-butylene glycol in blood and cerebrospinal fluid show that alterations of the cerebral pyruvic acid metabolism are difficult to detect in circulating blood.

Mit Unterstützung des «Schweizerischen Nationalfonds» und der Firma F. Hoffmann-La Roche & Co., AG, Basel.

5. Mitteilung. — 1. Mitt.:H. Thölen, F. Bigler undH. Staub, Path. Microbiol.24, 262 (1961). — 2. Mitt.:F. Bigler, H. Thölen undH. Staub, Helv. physiol. Acta19, C11 (1961). — 3. Mitt.:H. Thölen, F. Bigler undH. Staub, Exper.17, 359 (1961). — 4. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.91, 1259 (1961).  相似文献   

15.
Summary Two possibilities for the action of radiations on biological objects are still remaining: the effect by radiation-hits and the action by photochemical or radiochemical effects. By means of irradiating well-known chemical «model-substances» one may be able to decide between these two possibilities and to understand the biological primary effect of radiations.Both of the theoretical perceptions are discussed and compared with the empirical facts. It is shown that in all well examinated cases of radiation effects upon biological elements or chemical systems, water or an other diluting is of essential importance. Radiation-energy is conducted from point of absorption to point of action by means of electronic transport or diffusion. Diffusion seems much more probable in biological systems.  相似文献   

16.
Summary Tyramine enhanced the production of acetoin from pyruvate in rat liver homogenates. A stimulation of acetoin synthesis was only observed, when tyramine was oxidized during the incubation. Tyrosol (p-hydroxyphenylethanol) stimulated acetoin synthesis whereasp-hydroxyphenylacetic acid and ammonia were ineffective.

Mit Unterstützung des »Schweizerischen Nationalfonds» und der Firma F. Hoffmann-La Roche & Co. AG, Basel.

8. Mitteilung. 1. Mitt.:H. Thölen, F. Bigler undH. Staub, Path. Microbiol. (Basel)24, 262 (1961). — 2. Mitt.:F. Bigler, H. Thölen undH. Staub, Helv. physiol. Acta19, C 11 (1961). — 3. Mitt.:H. Thölen, F. Bigler undH. Staub, Exper.17, 359 (1961). — 4. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.91, 1259 (1961). — 5. Mitt.:H. Thölen, F. Bigler, A. Heusler, W. Stauffacher undH. Staub, Exper.18, 454 (1962). — 6. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.92, 746 (1962). — 7. Mitt.:F. Bigler, H. Thölen undH. Staub, in Vorbereitung.  相似文献   

17.
Summary By means of a method permitting the continuous measurement of the dynamic stiffness of elastic structures, it was shown on the skeletal and heart muscle of the tortoise that during the latent period the elasticity remains unchanged in relation to the resting value.  相似文献   

18.
Summary The migration of leucocytes from the buffy coat is influenced by the glucose concentration in the medium, stimulation of migration results from concentrations of glucose up to 2%.. Higher concentrations of glucose up to 8%. have no effect. The stimulating effect of a constant concentration PLPS increases considerably over the whole range of glucose concentrations up to 8%.. Optimal stimulation by PLPS depends therefore on the glucose concentration.  相似文献   

19.
Summary The frequency of radio-induced fragments of chromosomes increases in ascites-cells of the Ehrlich-carcinoma at higher oxygen partial pressure, to which test animals are exposed during irradiation.  相似文献   

20.
Summary For the initiation of an arousal reaction, the stimulation of the reticular activating system by square waves of frequencies varying from 50 to 400 c/s was studied. To evaluate the stimulation efficiency, the initial frequency of the rhinencephalic arousal reaction was used. The optimal stimulus frequency depends on the duration of the pulses. The optimal frequency was found to be 200 c/s at a pulse duration of 0.5 ms and 100 c/s at a pulse duration of 1.5 ms.  相似文献   

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