摘要:

Summary.1 Iron absorption tests were performed in rabbits. In 34 experiments 100 mg of ferrous iron was administered orally.2 20–60 minutes after iron administration the animals were laparotomized in Numal narcosis. Puncture of vena porta and vena cava, in a small group of experiments also vena hepatica and vena duodenalis, was performed.3 In 32 experiments out of 34 the serum iron level of the porta blood was higher than that of the cava blood. The difference varied between ‐8 and +214 γ%, with an average value of + 46,9 ± 8,1 γ%.4 The high serum iron level of the porta blood during iron absorption reflects the enrichment with iron during the passage through the digestive tract. To some extent the difference between porta and cava blood could be explained by the fact that it is necessary in order to heighten the serum iron level of the total blood volume. But the big differences often observed could be explained only by the assumption that iron is taken up by the liver from the porta blood. In some experiments the retention of iron in the liver could be directly demonstrated by means of comparison of the serum iron level of the porta blood and the

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00556.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.1 Iron in the form of ferric ammonium citrate was administered intravenously to rabbits in doses of 0.5–2.0 mg per kilogram of lwdy weight.2 The serum iron values observed within two minutes after the injection never exceeded 30 per cent of those calculated. In many cases they were materially lower than that. The following course of the serum iron curve showed a successive decline. After four hours the serum iron level still was above the initial fasting level.3 The “disappearance” of 70 to 80 per cent of the iron, already (luring the time of injection, is probably the result of a rapid distribution between the blood plasma and the extracellular tissue fluid. The following successive decline is probably explained by iron absorption of the tissue cells, to some extent perhaps also by excretion in the urine.4 The toxic signs following the injection of iron intravenously in relatively large doses are reported. The individual variations we

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00557.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.The reaction of the glantlular cells in the submaxillary and sub‐lingual glands of the rat has been cytologically investigated on indirect stimulation, before and after partial sympathetic or parasympathetic denervation. A clear explanation of the results obtained could be presented on the basis of neuro‐secretory units in these glands. On the other hand a diffusion of the chemical mediators according to the view of Cannon and Rosenblueth seems not to have any significant importance for the innervation. Thus the present results support the conception concerning the functional organization of the peripheral autonomic nervous system advanced in a previous pa

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00558.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.1 Valsalva's experiment was carried out on 25 healthy subjects of whom 13 were smokers and 12 non‐smokers before and after smoking of 1–3 cigarettes. In twelve of these subjects control experiments without smoking between two successive Valsalva experiments were carried out.2 Smoking did not as a rule alter the resting heart rate in non‐smokers, but increased it on an average for 16 beats/min. in smokers.3 The total increase or decrease in heart rate during and after the strain was used as a measure of reactivity. It varied in different subjects, some showing no increase in heart rate at all. Occasionally the type of response obtained in a certain subject could be altered. The smoking tends to decrease the reactivity when effective. A significant correlation between heart rate response and alteration in the height of the P and T waves was found. No correlation between P‐Q time and reactivity seemed to exist.4 The mean electrical axis (and changes caused by strain and by smoking) was calculated with the help of the Dieuaide's chart. The strain tends to deflect the axis rightwards. Smoking did not as a rule affect the mean direction of the electrical field. In 5 instances, however, a leftward shift in the axis was noted. There was no correlation between the size of the heart rate reaction and the rightward deflection of the axis during the strain.5 Certain special electrocardiogratphic findings will be treated in

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00559.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.The threshold of retinal on/off‐elements, isolated by the micro‐electrode technique in the cat retina, have been determined for three wave‐lengths as test light, a red, a green and a blue, before and after adaptation to one of three adapting lights, Ilford spectral green, blue or red.Statistical threshold correlations were calculated. Blue and red as well as blue and green proved to be independent for on‐ and off‐component, but there was a negative correlation of ‐0.46 between Green on‐components and Red off‐components, signifying that a certain number of the elements, responding best to green at onset could not respond to red at cessation of illumination, as would be required by a mechanism of contrast.Adaptation with the three adapting colours was found to give a number of highly selective and extremely variable effects in terms of the three test lights.The amount of depression, caused by coloured adaptation, was found to depend on the off/on‐ratio in such a fashion that the on‐sensitive elements tended to loose sensitivity at ‘on’, the off‐sensitive at ‘off’.For some elements the off/on‐ratio was found to increase towar

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00560.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.Single spikes have been recorded by the micro‐electrode technique from the retina of the fully dark adapted decerebrate cat, the aim being to determine the curve of the scotopic dominator with a maximum degree of accuracy in order to find out whether it corresponds with the visual purple (V. P.) distribution of sensitivity as known from work on retinal extracts.The pure on‐elements and some of the on/off‐elements gave a curve slightly narrower than the V. P. curve (e. g. figs. 1 and 2).Some on/off‐elements behaved differently. There were humps in the long and short wave‐lengths in the regions where previously modulators have been noted. In some elements unexpectedly large values were obtained at 0.420 μ (e. g. figs. 3–6).It is concluded that, since the V. P. chromophore would be a complex structure with several conjugated double bonds, it may exist in the retina in states of different probability depending upon the free radicals and the recep

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00561.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.Investigations on the relation between morphological factors and the presence of hyaluronidase in bull testes are described. A very close correlation has been found to exist between the activity of the spermiogenesis and the hyaluronidase content. It would seem, however, that complete spermiogenesis is not required for the production of hyaluronidase. Thus the presence of hyaluronidase probably is a condition for fertility, but its occurrence is notper sean indication of the capacity to fertilize.The size and the dry substance content of the testis possess a certain correlation with the hyaluronidase content.The formation of hyaluronidase in cells in general is discussed.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00562.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.We injected P32into Cisterna magna of rabbits. The speed with which this P32enters into the brain has been determined. It was found that the radioactivity increases gradually in the different parts of brain with approximately the same rapidity. The maximum was reached after 35 minutes.The turnover of radioactive orthophosphate to organic bound phosphate in brain was measured.The different theories for the brain protective barriers have been discussed.The data supports the view that there are two ways of supplying the brain with P32. Some minor parts mainly the hypophysis, the pineal body, the plexus chorioidei and the vegetative centers in hypothalamus are supported mainly by the blood. The nervous tissue on the other hand seems to exchange phosphate via the cerebrospinal fluid.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00563.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.The transmitter of sympathetic vasoconstrictor impulses to the hind limbs of the dog lacks vasodilator action. The transmitter is not adrenaline. It night be nor‐adrenaline or a substance with similar biological propertie

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00564.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary.No evidence was found for the existence of a sympathetic vasodilator innervation to the skin of the hind limbs or the ear of the dog.Nor‐adrenaline has a pronounced vasoconstrictor action on cutaneous vessels. The observation agrees with the idea that the substance might be the transmitter at vasoconstrictor nerve endings.Adrenaline has a pure vasoconstrictor action on cutaneous vessels, even in low concentrations.Acetylcholine has a pronounced vasodilator action on cutaneous vessels. Thus it cannot be excluded as a possible transmitter at cutaneous vasodilator nerve encling

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1949.tb00565.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY