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91.
Cardiac output distribution in the rat was found to be affected by age. Cardiac index and blood flow to the liver, kidneys, skin and skeletal muscle were lower in 11-12 month compared to 3-4 month old rats.  相似文献   
92.
In the rabbit jejunum, the elevation of temperature within the range of 25-37 degrees C diminished the sensitivity to noradrenaline (NA) for both the relaxation and amplitude inhibition. The relaxation by NA was mainly mediated via adrenergic beta-receptors at 25, 30 or 37 degrees C. The amplitude inhibition was mediated via alpha-receptors at 37 degrees C, and both alpha- and beta-receptors at 30 or 25 degrees C.  相似文献   
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94.
Summary The authors show the antibiotic activity of water-insoluble salts of hydrosoluble antibiotics in the case of penicillin G (salts of iron, copper, silver, gold, and uranium) and streptomycin (oleate).  相似文献   
95.
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   
96.
Summary The action of DDT on honey-bees depends to a high extent on the temperature (see graph). At 36°C (breeding temperature) DDT has a far weaker insecticidal action than at 20°C (laboratory temperature). This shows that the insecticidal properties of DDT diminish with the raise of temperature.This resistance to DDT at higher temperature is most propitious for bee-keeping and also explains the fact why in agricultural practice there has been no corroborated case of poisoning of bees, though in laboratory tests DDT avered itself to be toxic to bees.  相似文献   
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98.
Summary (1) By precipitation with ammonium sulfate, streptomycin, or calcium salts, we obtained from the pulp of tomatoes a substance containing carotinoids. The behaviour of this substance was analogous to that of chloroplst-substance and to that of animal cytoplasmatic nucleoproteins. Like these it contains proteins, lipids, and very probably nucleic acids. We regard this substance as achromoplastine.(2) Experiments with slices of green tomatoes show that the changing over of the chlorophyll content into the carotinoid content is inhibited by the presence of streptomycin.(3) Streptomycin inhibits the formation of chlorophyll in etiolated separated cabbage leafs, just as this drug inhibits the formation of chlorophyll in growing seeds.(4) The development of anthocyanides is not influenced by streptomycin.  相似文献   
99.
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   
100.
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