Wirkungsmechanismus des Urethans bei Leukämien

Summary Examinations of the blood and bone-marrow in healthy persons and patients with chronic leukemia have shown that the remarkable influence of urethane in chronic leukemias is due to an elective inhibition of the karyokinesis of the leukemic neoplastic cells. On the other hand the mitosis of the normal blood-cells is influenced hardly, or not at all, with the same therapeutical doses. Contrary to arsenic, urethane does not cause any increased maturation of the immature leukemic cells. Therefore the cell formula in the bone-marrow and the spleen is very little changed except for a marked increase of the erythroblasts. The importance of this finding (elective inhibition of the karyokinesis) for further investigation in the treatment of neoplastic diseases is discussed.     

Glukose als Cofactor bei der Retraktion des Blutgerinnsels

Summary Dextrose is found to be a co-factor for clot retraction. During retraction lactic acid is produced, suggesting a close relationship between enzymatic activity of the platelets and the retraction-mechanism.     

Die Rudimentation des Rumpfkanals bei kavernikolen Populationen des Astyanax (Characidae,Pisces)

Summary The lateral canal of the eye- and pigment-reduced cave populations of Astyanax mexicanus shows fragmentations. This is in contrast with the epigean ancestor and is attributed to the loss of its biological function.

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Die Rudimentation des Rumpfkanals bei kavernikolen Populationen des Astyanax (Characidae, Pisces)

     

Histologische Veränderungen der Magenschleimhaut des Hundes bei wiederholter Tetrachlormethanzufuhr

Summary Long-term administration of tetrachloromethane led to cirrhosis of the liver in dogs. Neither a repeated administration of the hepatotoxic substance nor cirrhotic changes of the liver led to changes of the gastric mucosa. The histological picture of the gastric mucosa was the same in dogs with liver cirrhosis as in healthy animals.     

Die Unterdrückung des letalen anaphylaktischen Schocks bei der Maus

Summary The effect was investigated of Endoxan (cyclophosphamide) on anaphylactic shock in mice, induced with the aid of pertussis organisms. A complete inhibition by a dose of 4 mg/mouse can be proved. The formation of antibodies in the Endoxan-treated mice is depressed.     

Eine Methode zur Bestimmung des Endpunktes der Sol-Gel-Umwandlung bei der Plasmagerinnung

Summary In order to measure the clotting time of blood plasma the sol-gel transformation is observed. The process is retarded with mol/18 of 1,4-oxyphenyl-sulfonate. A lowering of the prothrombin content of 50% results in a difference of time against normal values of 45–55 sec., compared with 3–4 sec. with the method ofQuick.     

Pharmakologische Untersuchungen bei Thiaminmangel I. Änderungen des Katecholamingehalts im Gewebe

Summary (1) The increased tissue catecholamine level of the thiamine deficient rat was shown in the atrium, the ventricle, the brain cortex and in the spleen but not in the brain stem and the adrenal gland. (2) The increased response to tyramine of the thiamine deficient heart is most probably due to the high catecholamine level caused by thiamine deficiency. (3) The increased catecholamine content in the thiamine deficient rat does not result from the increased pyruvic acid.

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Herrn Professor Dr.F. Th. von Brücke zum 60. Geburtstag im Januar 1968 gewidmet.     

Änderung des Glukosetransports frischer menschlicher Erythrozyten bei längerer Inkubation

Summary Incubation of fresh defibrinated blood at 37°C increases the volume of red cells and decreases their permeation rate for glucose. The kinetics of sugar transport show direct proportionality between rate and the osmotic content of red cells. The measured volume changes and the changes of osmotic content calculated from the glucose permeation curves are in good agreement. Adenosine reconstitutes the increased volume and the decreased permeation rate in red cells. Therefore the decrease in permeation rate is explained by the increase in volume.     

Dämpfung des Kältezitterns durch Pentobarbital und Pethidin bei Ratten

Summary In rats, shivering was induced by cooling. Shivering started at 36.6°C in unanaesthetized rats and at 36.0°C in animals with light pentobarbital anaesthesia (5 mg/kg i.V.). Pethidine (2 mg/kg) lowered the onset of shivering in unanaesthetized rats to 35.3 °C and in anaesthetized animals to 33.0°C. The results suggest that the effect of pethidine upon shivering is potentiated by pentobarbital.     

Beeinflussung des Generationszyklus und seiner Teilphasen bei Ehrlich-Aszitestumoren verschiedener Ploidie durch Cyclophosphamid

Summary The effect of the alkylizing agent cyclophosphamide (100 mg/kg i.p.) on the cell cycle of the diploid (EAT dipl.) and hypertetraploid (ELT) Ehrlich ascites tumor growing in the peritoneal cavity of male NMRI-mice has been studied by autoradiography with H³- and C¹⁴-thymidine (double labelling technique and method of labelled mitoses). The results suggest that the proliferation kinetics of tumor cells after administration of cyclophosphamide is dependent essentially on the type of tumor strain tested.     

Hemmung des durch blutdrucksenkende Pharmaka bei Ratten ausgelösten Trinkens durch Nephrektomie

Summary The drinking response of rats seen after the hypotensive drugs phentolamine, isoproterenol and hydralazine/bretylium can be abolished by nephrectomy. It is postulated, that the dipsogenic activity of these drugs is mediated by renin.     

Das Reserpin bei experimenteller Thyreotoxikose: Seine Wirkung auf die Adenosinnucleotide des Herzgewebes

Riassunto L'aggiunta di reserpina ad una dieta contenente estratto di tiroide, produce nei ratti un aggravamento della sintomatologia tireotossicosa caratterizzato da aumento della mortalità, maggiore inhibizione dello sviluppo corporeo ed ulteriore caduta delle concentrazioni cardiache di ATP, ADP e AMP.Si suggerisce che tale effetto sia dovuto ad un potenziamento da parte della reserpina dell'azione della tiroide sul metabolismo del tessuto cardiaco.     

Einbauunterschiede in den Zellschichten des Cortex nach Markierung mitd,l-Prolin-H3 bei der Maus

Summary Autoradiographic studies of the mouse brain following incorporation ofd,l-proline-H³ andl-histidine-H³ show a wide variation of the regional uptake ofd,l-proline into the cerebral nerve cells, in contrast tol-histidine. In the cerebral cortex proline is to be found only in the nerve cells of the lamina ganglionaris (V) and lamina multiformis/infima (VI/VII). Subsequent translocation of radioactivity is indicative of an axoplasmic flow of proline-labelled substances into the distal parts of the neuronal processes.

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Mit dankenswerter Unterstützung durch das Landesamt für Forschung Nordrhein-Westfalen.     

Orientierende netzhautnahe pH-Messung im Glaskörper des Kaninchens bei intravenöser Glukose-infusion

Summary After i.v. infusion of glucose a decrease of pH to 6,85±0,12 measured in the vitreous body of the rabbit eye near the retina can be recorded.     

Analyse des akustischen Geschlechtererkennungsmechanismus (Befreiungsrufe) bei Kröten (GenusBufo)

Summary The release calls of male European toads (B. bufo L.,B. calamita Laur.,B. viridis Laur.) have been described and recorded in the form of spectrograms and oscillograms. While only 1 type of release call is uttered byB. bufo, inB. viridis andB. calamita 2 and 3 types respectively were found. The latter 2 species show a close relationship,B. calamita being the most highly developed toad in Europe.     

Aminosäurenanalyse des Ferritins bei primärer und sekundärer Lungenhämosiderose

Summary Amino-acid composition of the ferritin from lungs in a case of Goodpasture's syndrome, as well as cardiac pulmonary hemosiderosis, was examined. Ferritin in the case of Goodpasture's syndrome was found to contain cysteinic-acid, the significance of which is discussed.