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631.
Summary (1) In the isolated mammalian heart (rabbit, cat, dog) electrically induced ventricular fibrillation is stopped in practically 100% of the cases by adenosin-triphosphoric acid (ATP) in doses of 0.25–20 mg, and the normal rhythm of the heart is permanently restored (as far as the experiment extends).(2) This effect of ATP follows from a primary blocking, which leads to a complete cessation of the activity of the ventricles with diastolic dilatation of the heart.(3) In as much as adenyl acid from yeast and adenosin (in large doses) also stop ventricular fibrillation, the energetic effect of ATP seems to be of no importance in stopping it; it is a specific effect of the adenyl compounds on the bundle ofHis. 相似文献
632.
Summary Five species ofChiroptera were studied and the following numbers were found:Rhinolophus hipposideros Bechst.N=27;Barbastella barbastellus Schr.N=16;Plecotus auritus L.N=16;Myotis myotis Bork.N=21;Miniopterus schreibersii Kuhl,N=23. Centric fusions occur in the chromosomal evolution ofChiroptera. Sex-chromosomes ofX-Y type. 相似文献
633.
Summary Traces of nor-adrenaline restore the vascular action of adrenaline altered in epinephrectomized dogs to the reaction of the normal animal. Therefore it is claimed that the adrenals discharge one or several substances into the blood stream, which are necessary for the usual peripheral vascular action of adrenaline. Further investigations are in progress. 相似文献
634.
Summary The application of diphenylilacetic acid has shown favorable effects on the growth of tobacco plants. Solutions containing 10 p.p.m. and 20 p.p.m. produce, in weight, an almost double growth in treated plants in comparison with the controls. Diphenylilacetic acid can be considered as a growth-promoting substance. The data are not definite. 相似文献
635.
R. Cavelti 《Cellular and molecular life sciences : CMLS》1948,4(12):489-490
Summary (1) No double refractile Iipoid droplets can be obtained by alcohol ether extraction from urine or from urinary protein as it is possible from blood serum.(2) The conclusion is drawn that the double refractile lipoids droplets in urinary sediment do not pass through the glomeruli and therefore are not reabsorbed by the tubuli, but that they come from the own lipoproteins of the epithelial cells of renal tubuli and pass into urine by dissolution and desquamation of these cells. 相似文献
636.
Ferrero C. Duchosal P. W. Doret J. P. Andereggen P. Rilliet B. 《Cellular and molecular life sciences : CMLS》1948,4(6):236-238
Summary Cardiac catheterization, initially conducted byForssmann in 1929, has become a qualified clinical method. A fine rubber catheter is introduced into the antecubital vein and mechanically reaches the right heart chambers; auricular and ventricular, as well as the pulmonary artery. In some exceptional cases the left auricle and ventricle likewise lend themselves to exploration. 相似文献
637.
R. Cavelti 《Cellular and molecular life sciences : CMLS》1948,4(12):487-489
Summary (1) Doubly refracting lipoid droplets can be demonstrated in normal and pathological sera by means of alcohol ether extraction. This is not possible with ether extraction alone.(2) These lipoid droplets can be demonstrated only, or almost only, when they are precipitated out of alcohol or ether alcohol 相似文献
638.
A. C. Muhr 《Cellular and molecular life sciences : CMLS》1948,4(9):355-355
Summary The fatty acids from dehydrated castor oil, mainly consisting of 9,11- and 9,12-linoleic acid, show in biological tests vitamin effects similar to those of the so-called essential fatty acids. 相似文献
639.
Summary An alcaloid C16H19NO3 has been isolated fromErythrina tholloniana; the iodohydrate of this erythroidine has a melting point of 225°C and 239°C for its chlorhydrate. It has a powerful curare-like action on the frog or on its isolated sciatic-sartorius preparation; at a concentration of less than 1/1,000,000, a complete neuromuscular block is produced: the electrical stimulation of the motor nerve does not produce any contraction, but the muscle reacts by an end-plate potential having the same characteristics (shape, duration, possibility of summation) as the electrical waves produced in the same preparation curarized by ordinary curare or by quaternary ammonium derivatives. Decurarization by veratrine 1/200,000 is accompanied by the same electrical reactions as those which have been described in preparations treated by curare.On mammals, the alcaloid has little curariform activity; on the isolated phrenic-diaphragm preparation of the rat, incomplete block was produced at a concentration of 1/5000. 相似文献
640.