bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations on the Pulmonary Arterial Blood Pressure in the Cat
Authors: EULER U. S. v. , LILJESTRAND G.
Published: December 2008

The pulmonary arterial blood pressure was recorded in anaesthetized cats by means of a special cannula, according to MELLIN's technique. In most experiments the thorax was closed and the animal was breathing spontaneously.

The pulmonary arterial pressure in 9 experiments averaged 23 cm water, or approximately 17 mm Hg, at an average systemic pressure of 132 mm Hg. The average ratio thus was about 1: 8, with the limits 1: 5 and 1: 14.

Pressure variations of 1–2 cm blood synchronous with the breathing were regularly recorded. In one case, slow large waves of 1–2 minutes duration and about 5 cm amplitude were observed.

Even great variations in the systemic blood pressure, elicited from the pressoregulating reflex mechanisms, were hardly accompanied by variations in the pulmonary arterial pressure.

During muscular work a moderate rise in pulmonary blood pressure generally occurred, greater when air was breathed than when oxygen alone was administered.

Clamping the pulmonary artery to one lung did not cause any change in systemic pressure (confirming LICHTHEIM and TIGERSTEDT) but caused a moderate rise in pulmonary arterial pressure.

Breathing of pure oxygen lowered the pulmonary arterial pressure and oxygen‐lack raised it. Carbon dioxide 6.5–20.5 per cent in oxygen raised the pressure sligthly, but constantly. These effects were not influenced by vagotomy.

The effect of injections of adrenaline, nor‐adrenaline, acetylcholine and histamine and of stimulation of pulmonary nerves were studied in some cases.

The experiments seem to warrant the conclusion, that the regulation of the pulmonary blood flow is mainly mediated by a local action of the blood and alveolar gases leading to an adequate distribution of the blood through the various parts of the lungs according to the effeciency of aeration.
The Hydrodynamics of Semi‐Permeable Tubes with Reference to the Glomerular Function of the Kidney
Authors: BRUN CLAUS , KNUDSEN E. O. E. , PETERSEN CHR. STEEN , RAASCHOU FLEMMING
Published: December 2008

In some experiments on the renal function in the horizontal and erect postures the authors observed certain changes in the inulin clearance (glomerular filtration) and the diodrast clearance (renal blood flow) which, compared with the changes occurring in the erect posture in the pressure and composition of the blood (colloid osmotic pressure, cell volume and viscosity), necessitated penetrating into the problems of glomerular hydrodynamics.

 The hydraulic problem is the following: What laws govern the laminar flow of colloidal solutions in semi‐permeable tubes?

 Formulae are deduced for flow, filtration, hydraulic and colloid osmotic pressure in a semi‐permeable tube perfused by a colloidal solution.

 The validity of the formulae for water and plasma is proved by model experiments.

 The formulae are employed for calculating the results of a concrete experiment made to determine the renal function in the passive erect posture. From these calculations the authors plot the course of the hydraulic and colloid osmotic pressures in a glomerular capillary for horizontal and erect postures.

The course of these curves shows that a contraction of vas efferens must take place in order that the observed simultaneous changes in the inulin and diodrast clearances and in the composition and pressure of the blood may occur.
On the Influence of Muscular Work on the Citric Acid Content of Human Bloodserum
Authors: AGRELL INGA‐GRETA
Published: December 2008

By THUNBERG'S enzymatic method the citrate content of serum has been determined on human blood from the cubital veins of healthy subjects. The blood samples have been drawn, an A‐sample before rising, a B‐sample after the subject having performed a certain muscular work and a C‐sample following a 1–2 hour's rest (bed‐site) after the B‐sample. 19 series have been carried out in all. For the 19 A‐samples the minimum‐value, mean‐value and maximum‐value were 23, 28, and 33 γ citric acid per ml. serum. The corresponding values for the B‐ and C‐samples were 24, 32, 41 and 24, 31, 36. The Ci‐value is increased through muscular work. Using the Ci‐value of serum for diagnosis one has to take the blood‐sample before rising. As upper limit for healthy subjects one can fix 30 γ Ci. Of 19 values only 3 are a little higher. When the bloodsamples are taken after the beginning of the day's work as on an out‐patient's department of a hospital the Ci‐values are more variable, and have to be estimated with reservation.
The Mode of Entrance of Sodium into the Aqueous Humour.1
Authors: BÁRÁNY ERNST H.
Published: December 2008

The rate of accumulation of radio‐active sodium in the aqueous humour of the rabbit is not appreciably influenced by the blood pressure reduction caused by occlusion of the common carotid artery. If sodium had entered the aqueous by ultrafiltration, a material reduction of the rate of entrance would have occurred. Consequently sodium does not enter the aqueous by ultrafiltration but mainly by secretion.
On the Function of the Pineal body.
Authors: BORELL ULF , ÖRSTRÖM ÅKE
Published: December 2008

1. The phosphorus turnover of the pineal has been studied with the aid of radioactive phosphorus in rats of different ages and compared with the turnovers of the adenohypophysis, neurohypophysis, tuber cinereum and cerebellum. The activities in these organs with exception of cerebellum are lowest during the first 10 weeks of the life of an animal. In the fertile age the activity remains at a constant high level and with exception of the neurohypophysis increases somewhat during senility. The activity of the cerebellum remains unchanged.

2. Of the 42 organs and parts of the brain investigated, the phosphate metabolism decreased only in the ovaries after epiphysectomy to a statistically probable extent. Considerable increases in the turnover were also observed in the adenohypophyss, neurohypophysis and tuber cinereum in females.

3. After castration an increased phosphorus turnover was obtained in the pineal body and the adenohypophysis. This increase was most pronounced in females.

4. It appears to follow from these results that the pineal exerts an influence, directly or indirectly, especially upon the ovaries. There appear to be reciprocal effects of a similar nature between the ovary and the epiphysis as between the adenohypophysis and the ovaries.

We wish to express our thanks to Professor Manne Siegbahn for his kindness in placing radioactive phosphorus at our disposal.
The Relative Importance of Ultrafiltration and Secretion in the Formation of Aqueous Humour as revealed by the Influence of Arterial Blood Pressure on the Osmotic Pressure of the Aqueous.
Authors: BÁRÁNY ERNST H.
Published: December 2008

Sodium has been shown to enter the aqueous predominantly or wholly by secretion. Therefore, if the aqueous were a mixture of a secretion and any considerable amount of ultrafiltrate, the osmotic pressures of these two components would have to be markedly different. A blood pressure reduction which changes the amount of ultrafiltrate in the aqueous would consequently change the osmotic pressure of the aqueous.

The osmotic pressure difference between the aqueous humours of both eyes was measured in rabbits after the blood pressure of one eye had been kept at 30 mm Hg below the normal level for 1.5—2 hours. No significant difference in osmotic pressure was detected. Therefore, the amount of ultrafiltrate in the aqueous cannot be considerable.

This investigation has been made possible by a grant from the Lennander Foundation of the University of Uppsala. Miss G. Thelin AND Mr. A. Rüütli have given most valuable assistance
A Specific Micro‐method for Colorimetric Determination of Methanol in Blood.
Authors: AGNER KJELL , BELFRAGE KARL ERIK
Published: December 2008

1. A method for colorimetric determination for methanol has been described.

2. The rate of elimination of methanol in blood has been determined. At a methanol concentration of more than about 1 % the rate of elimination was about 0.0017 %per min. and at lower concentrations the value was about 0.0006 % per mm.

3. It has not been possible to demonstrate formaldehyde in blood in cases of methanol intoxication.

4. The simultaneous occurrence of ethanol prevents the elimination of methanol.
The Action of Atropine, Homatropine, Eserine and Prostigmine on the Osmotic Pressure of the Aqueous Humour.
Authors: BÁRÁNY ERNST H.
Published: December 2008

The influence of atropine, homatropine, eserine and prostigmine on the osmotic pressure of the aqueous humour has been studied in rabbits.

In previously untreated eyes eserine caused an osmotic pressure reduction equivalent to 0.74 ± 0.31 mM NaCl. In eyes habituated to eserine and prostigmine, no influence on the osmotic pressure was detected.

Atropine and homatropine caused a reduction in osmotic pressure equivalent to 0.24 ± 0.12 mM NaCl.

The decreases in osmotic pressure can probably be attributed to an increased permeability of the blood‐aqueous barrier.
A Quantitative Determination of the Content of Contractive Substances in Human Sperm and their Significance for the Motility and Vitality of the Spermatozoa.
Authors: ASPLUND JAN
Published: December 2008

1. The total content of contractive substance in human sperm was determined from 155 specimens of sperm by titration on rabbit intestine in vitro, with prostaglandin as the standard. The content varied greatly in different specimens, but contractive substance was met with in all of them.

2. In certain specimens the factor which is active on rabbit intestine consists – apart from prostaglandin and choline – of at least one other substance, which leads to a very rapid increase in tonus and is indifferent to atropine.

3. There is no correlation between the total content of contractive substance and the motility and life of the spermatozoa.
Experiments on the Influence of Electric Current Upon Growing Nerve Cell Processes in Vitro.
Authors: INGVAR DAVID
Published: December 2008

With a new technique experiments are made to verify S. Ing‐var'S statement (1920) that electric currents can direct the nerve cell processes in vitro. Current intensities of 10‐6–10‐3 A were used. No influence could be traced.
On the Effect of Adenosine Triphosphate on Myosin Threads.
Authors: BUCHTHAL FRITZ , DEUTSCH ADAM , KNAPPEIS G. G. , MUNCH‐PETERSEN. AGNETE
Published: December 2008

In confirmation of Szent‐Gyorgyi et al. we find that ATP causes a strong volume constriction in myosin threads. This effect occurs in threads prepared both from enzymatically active and practically inactive myosin.

Adenosine diphosphate and inosine triphosphate which release contraction in the muscle fibre, are without effect on the myosin thread.

Birefringence decreases considerably during the shortening produced by ATP, while it increases when shortening is prevented.

Sulfhydryl reagents reduce the changes in volume and birefringence produced by ATP in the myosin thread and also make a muscle fibre less excitable by ATP and electrical stimuli.

Creatine phosphate, sodium triphosphate, sodium pyrophosphate and sodium ortophosphate, ineffective as such, likewise reduce the effect of ATP, while it is enhanced by inosine triphosphate.

Previous treatment with acetylcholine reduces the effect of ATP only in enzymatically inactive dried myosin threads.

Threads which show a strong shortening ability towards ATP in a tensionless condition, react with a considerable decrease in stiffness and increase in equilibrium length even at loads which in the untreated thread only produce a stretch of 0.1 per cent. Both effects are interpreted as being due to the release of a certain proportion of elastically active linkages in the minute structural elements by ATP.

The work has been supported by the Michaelsen Fond, Nordisk Insulin Fond and Overretssagforer L. Zeuthens Mindelegat.
Über die Quantitative Wirkung des Pnffernervenmechanismus auf die Blutdruckauswirkungen des Adrenalins.
Authors: KUMPAS H.
Published: December 2008

1. Die nach der Höhe des Blutdruckausschlages im Blutdrucktest bestimmte minimale Wirkungsdosis blieb sich bei intakten Puffernerven in 3 Fällen von 16 nach Durchschneidung der Puffernerven gleich. In diesen 3 Fällen war die minimale Wirkungsdosis durch den Puffermechanismus nicht maskiert. Bei den übrigen 13 Fällen wurde die minimale Wirkungsdosis durch den Puffermechanismus maskiert. Da bei diesen Versuchen die Vagi vor Beginn der Versuche durchgeschnitten waren, rühren diese Befunde von der vaskularen Gegenregulation her.

2. Die isolierte Vagotomie, bei der die Depressoren und die Sinusnerven intakt geblieben waren, übte keinerlei Einfluss auf die minimale Wirkungsdosis noch die Höhe des Blutdruckausschlages in einem anderen Dosierungsbereich aus. Wenn die Vagi zusammen mit den Depressoren durchgeschnitten wurden, die Sinusnerven aber intakt blieben, konnte man in 5 von 8 Fällen keine Vergrösserung der Blutdruckausschläge konstatieren. Bei den übrigen 3 Fällen vergrösserten sich die Blutdrucksauschläge entsprechend der Dosisgrösse, mit Ausnahme der kleinen Dosierun‐gen – bis 0.6 γ/kg, deren Blutdruckeffekte ihre frühere Höhe beibehielten.

3. Die manifesten Blutdruckeffekte des Adrenalins werden betreffs ihrer Höhe von den vasodepressorischen Reflexen herabgedrückt. Bei 8 von insgesammt 12 Fällen entsprach die Vergrosserung der Blutdruckeffekte der Relation der sich auf die Höhe des Blutdruckanstieges beziehenden Effektivität der vasodepressorischen Eeflexe. Bei den rest lichen 4 Fällen gab es keine Vergrösserung der Blutdruckeffekte kleiner Dosen, doch konnte diese anlässlich grösserer Dosierungen beobachtet werden. Hier trat diese bei 8 Fällen vorhandene Relation nicht in Erscheinung. Es kann angenommen werden, dass diese Verschiedenheit davon herrührt, dass der Ausgangsblutdruck dieser Tiere unter den Versuchsbedingungen niedriger als normal war, denn em diesen 4 Fällen entsprechendes Verhalten konnte man beim gleichen Versuchstier mit niedrigerem Ausgangsblutdruck vorführen, wogegen man bei höherem Ausgangsblutdruck ein den 8 Fällen entsprechendes Verhalten konstatieren konnte.

4. Die vasodepressorische Reflexfolge begann von einer gewis‐sen grösseren Dosis an schwächer zu werden um zuletzt zu verschwinden. In grossen Dosen greift das Adrenalin zerstörend in die Verrichtung der Pufferreflexmechanismen ein und es wird eine Frage der Dosierung sein, in welchem Ausmasse diese Reflexe wirksam bleiben.
The Occurrence of Citric Acid in the Human Thyroid Gland.
Authors: BROLIN S. E. , THUNBERG T.
Published: December 2008

The investigation is based on a material of 75 thyroid glands of man which have been obtained in routine autopsies.

On the basis of this material the general occurrence of the citric acid in the human thyroid gland was established and the concentration thereof quantitatively determined. The mean value of the citric acid concentration was found to be 890 p. p. m. In the determination of this value the undeveloped and rather Ciscarce glands of subjects less than one year old have been excluded. The standard deviation is 420 p. p. m. Compared to the blood and most tissues the citric acid concentration of the human thyroid gland is remarkably high, amounting almost to 1 mg. per gram of glandular tissue.

If the gland‐material investigated is classified after the colloid content the citric acid has been found to increase greatly with the increase in the colloid content. The greater part of the citric acid is to be found in the colloid. In comparison with the colloid the concentration of citric acid in the follicular epithelium is low but otherwise no certain conclusions could be drawn. Some observations, however, suggest that the citric acid concentration in the epithelial cells may be considerably higher than in the blood.

The citric acid concentration in the thyroid gland increases greatly at first, and then more slowly up to the age of 25–30 years. After that period there is pronounced decrease, moderate and uncertain at first but gradually pronounced. With increasing age the citric acid increases again. This variation in the citric acid concentration agrees remarkably well with the structural changes of the age in question.

No variations in the citric acid concentration of the thyroid gland were shown to be primarily caused by disease. A secondary influence, however, has been observed owing to a change of the colloid content of the gland.

During the fertile ages of 15–45 years the citric acid concentration has been found identical in the two sexes. A sexual difference becomes evident, the female glands showing a considerably lower value during the subsequent 20‐year period. The probability that this difference is not accidental, has been calculated to 98.5 per cent. No corresponding difference in the structure of the thyroid gland during this period has been observed previously, and none has been evidenced in our material. No iodine determinations were carried out, but statistical calculation on the basis of data given in previous reports in the literature show no sexual differences in the age concerned.
An Electrolytical Method for the Determination of Cations.
Authors: ØRSKOV SØREN L. , RATJEN ERLING
Published: December 2008

The method is based on the solubility in mercury of the amalgams of the cations formed by electrolysis. The amalgams are extracted by rocking movements (Widmark) AND titrated.

The extraction velocity for some cations is determined.

Sodium (100 per cent) and potassium (98–99 per cent) are recovered after one hours rocking. After the same time 90 per cent of calcium are extracted, some of the calcium amalgam being precipitated on the glass wall.

Ammonium and guanidine are also extracted, but only slowly, magnesium and ferric ion can not be extracted.

Direct determinations can be made on serum and erythrocytes, it is important that the proteins are precipitated during the electrolysis. There is good agreement with the values found after ashing of serum; direct determination on the erythrocytes give a somewhat higher value than after ashing.

The analyses are carried out with 0.05 ml. serum.

The applicability of the method is discussed.
Non Absorption of Finely Emulsified Paraffinum Liquidum in the Intestine of the Rat.
Authors: LUNDBÆK KNUD , MAALØE OLE
Published: December 2008

.On injection into rat duodenum of emulsions of paraffinum liquidum tenue, prepared a. m. FRAZEE, AND with an average globular diameter of 0.3–0.5 μ, no absorption was found over a period of 6 hours.

It has thus been impossible to confirm this important support of the “Partition Hypothesis”.
The Concentration of Blood Lactic Acid in Man during Muscular Work in Relation to the Partial Pressure of Oxygen of the Inspired Air.
Authors: LUNDIN GUNNAR , STRÖM GUNNAR
Published: December 2008

The concentration of blood lactic acid was studied in subjects working on a bicycle ergometer and breathing nitrogen‐oxygen mixtures with a varying percentage of oxygen, with special reference to the conditions when the work had been continued long enough to ensure the reaching of a steady state of blood lactic acid. The rise from the rest value to the steady state value was found to have a certain inverse proportional relation to the partial pressure of oxygen of the inspired gas mixture. The causes of this fact, and of the effect of acclimatisation on blood lactic acid levels during work as investigated by Edwards, are discussed.
Protein Metabolism of Tissue Cells in vitro. 5. The Accessory Growth Substances in Sugar‐free Malt Extracts.
Authors: ASTRUP TAGE , FISCHER ALBERT , øHLENSCHLAGER VILH.
Published: December 2008

The accessory growth substances present in barley malt extracts were purified by means of fermentation with bakers yeast, alkaline precipitation with ethyl alcohol and precipitation in glacial acetic acid with ethyl alcohol. A dry powder containing most of the activity could be prepared. The active substances in the fermented solutions are considerably more stable than previously assumed.

Using such sugar‐free preparations it was possible to show the ability of the tissue cells to utilize glucose, fructose and man‐nose for growth purposes. Without the addition of the malt extracts the sugars were inactive.

This work was aided by a grant from “Teknisk‐kemisk Fond”. The barley malt was placed at our disposal by the Carlsberg Breweries and A/S “Ferrosan”, Copenhagen, has aided us in the preparation of crude extracts.
The Effect of the Food Intake on the Morning Value of the Citric Acid Concentration of the Blood.
Authors: WALLMAN‐CARLSSON CURT
Published: December 2008

The intake of food in the morning immediately after awakening causes an increase in the Ci‐value of the blood serum, measured by Thunberg's enzymatic method. In a series of 10 subjects the lowest increase was 5 %, the highest 32 %, and the mean value 20.6 %. When the method is used for diagnostic purposes in liver diseases, blood samples should be taken on an empty stomach and under so similar conditions as possible.
Studies on the Biochemistry of Human Semen.:Some Properties of Prostatic Phosphatase.
Authors: LUNDQUIST FRANK
Published: December 2008

The enzymatic hydrolysis of phosphoryl choline, the natural substrate of human prostatic phosphatase, jS‐glycerophosphate and phenyl phosphate has been studied.

1) The optimum pH when measured in acetate buffer solutions of constant ionic strength, is found to be about 6.0 for glycerophosphate and phenyl phosphate, and about 6.3 for phosphoryl choline.

2) Fluoride, zinc chloride, oxalate and maleinate are found to inhibit the enzyme to a varying degree. Citrate to some extent abolishes this inhibition, and furthermore increases the reaction velocity of glycerophosphate and, especially, phosphoryl choline hydrolysis, also when prostatic secretion or seminal plasma is used without added inhibitor.

3) The energy of activation is found to be about 11,500 cal for each of the three processes.

4) The affinities between enzyme and substrate were measured at 37° and 0°. For phosphoryl choline and glycerophosphate it is about 2,500 cal/mol (37°), and for phenyl phosphate about 4,200 cal/mol. The change in heat function is small (δH = 0 ± 1,500 cal/mol).
The Influence of Some Central Nervous Depressants on the Reciprocal Inhibition Between the Two Retinae as Manifested in Retinal Rivalry.1
Authors: BÁRÁNY ERNST H. , HALLDÉN. ULF
Published: December 2008

The influence of drugs on retina1 rivalry between a horizontal and a vertical bar was studied with the aim of finding pharmaco‐logical agents which might become useful in the treatment of suppression and amblyopia in squint,

Amytal, bromural, chloral, ethyl alcohol, phenobarbital and trional can weaken or abolish retinal rivalry. Under the influence of these drugs, completely simultaneous perception of the two dis‐parate objects may occur. I n less pronounced cases only a decrease in depth of suppression of the momentarily subjugated image is observed. Together with the decrease in intensity of rivalry the drugs cause a decrease in the frequency of alternation. If, in the normal state, there is an imbalance between the two competing pictures, one of them being dominant more than half of the time, the degree of imbalance usually increases when rivalry is weakened under the influence of the drugs.

Morphine in one case caused a marked increase, in two other cases uncertain decreases in rivalry. 3‐methyl‐5.5‐diphenyl‐hydan‐toin (one case) had no effect on rivalry.
Observations on the Hydrogen‐Activating Enzymes Present during the Metamorphosis of Insects
Authors: AGRELL. IVAR
Published: December 2008

The aim of this investigation has been t o study the variation of the intermediate oxidative metabolism during insect metab‐olism as reflected in the activity of the dehydrogenase systems. Pupae and praepupoe of %he fly Calliphora erythrocephala Meig, were used and proved to be excellent experimental material for this purpose.

The gas metabolism, oxygen consumption, and carbondioxide production, determined by means of the Thunberg‐microspirometer, described a U‐shaped curve during metamor‐phosis. It was shown by the application of Thunbergs' methylene blue method that the experimental animals were carriers of hydro‐gen‐activating enzyme systems. Variations in the hydrogen‐activating capacity of the dehydrogenase systems or their spon‐taneous activity are likewise U‐shaped and of the same order of magnitude as that of the gas metabolism. For this reason i t is assumed that the U‐shaped course of the respiration is, t o a cer‐tain degree, connected with variations in the activity of the de‐hydrogenase systems. There is, however, no absolute agreement between the variations in the gas metabolism and the dehydro‐genase activity. Variations in pH in the serum also give a U‐shaped curve.

About 30 organic compounds have been found capable of in‐creasing the hydrogen‐activating capacity of the experimental animals in vitro. There is reason to assume that corresponding dehydrogenases are active during metamorphosis. Also inhibiting substances are observed.

Changes in the hydrogen‐activating capacity due t o the ef‐fect of 16 different substances have been followed during the entire metamorphosis. The results obtained show systematic, periodically occurring variations in activity, which are considered an indication of the change in the potential activity of the respec‐tive dehydrogenase systems.

The fluctuations in the potential activity seem to occur at definite time intervals and for this reason it is thought that they represent generally critical periods in the intermediary oxidative metabolism during metamorphosis.

The changes in the activity of the succino dehydrogenase has been studied during the entire metamorphosis, as well as the inhibitory effect of malonate and the influence of succinate on the spontaneous activity during the same period. The results obtained give reason to assume the existence of a “succinic cycle” during the period of minimal metabolism during the metamorphosis.
On the Role of Glycollic Acid in Biological Methylation Processes
Authors: STEENSHOLT. GUNNAR
Published: December 2008

A brief review is given of certain current ideas on the rble of glycollic acid as a methylating agent. Next the results are reported of some in vitro experiments in which guanidine acetic acid and glycollic acid or glycine, and some other substances as well, wereincubated with suspensions of various animal tissues. The de‐terminations of creatine in the reaction mixtures were carried out both by the picric acid and by the dinitro‐benzoate methods. The results were negative: in no case could any trace of a creatine synthesis be demonstrated. Finally some perfusion experiments on the excised rabbit's heart were carried out. The results were in substantial agreement with the in vitro experiments. We may therefore be justified in concluding that glycollic acid is incapable of methylating guanidine acetic acid to creatine. The relation of these results to some previous investigations by other workers is discussed.
On an Amine Oxidase in Rabbit's Liver
Authors: STEENSHOLT. GUNNAR
Published: December 2008

The paper reports the results of an investigation of the enzyme in rabbit's liver that catalyzes the oxidation of mescaline. Another substrate for this enzyme is found. By inhibition experiments it is shown that the enzyme is in all probability structurally different from the mono amine oxidase. The experiments indicate that copper, iron, manganese and magnesium are probably of no importance for the enzymatic process. The r61e of metals is further discussed, and i t is shown that a suggestion about the nature of the mescaline oxidizing enzyme put forward by BERN‐HEIM and BERNHEIM is probably untenable.
Some Information on the Citric Acid Content of Bone Substance.
Authors: THUNBERG T.
Published: December 2008

The author summarizes our scant knowledge up to the present time of the citrate content of the bone system and reports new determinations carried out by him on humans, birds (Larus ridi‐bundus), fish (Clupea harengus, Gadus callarius and Scomber scombrus). The citrate determinations have been made by means of the colorimetric variation of Stahres pentabromaceton method introduced by Pucher, Shekman and Vickery, and finally with the modification worked out by Hunter and Leloir. The amount of citrate found has been put in relation to water‐free (ev. also fat‐free) substance. When expressed in this manner the value for humans, birds, and fish vary between one and a few percent. The Ci‐value in the frog, kept during the winter and not used until late in the summer, was about 0.3 %.
The Influence of Muscular Exercise on the Tolerance of Digitalis in Guinea‐Pigs.
Authors: ELMQVIST ADA , RYDIN HAKAN
Published: December 2008

Experiments have been carried out on guinea‐pigs, which were given daily doses of digitalis subcutaneously for one month. Its effects were followed inter alia by observing the mortality among and the weight of the animals. The minimum lethal dose for intravenous digitalis administration was determined on the surviving animals according to Knaffl‐Lenz. The following results were obtained:

The animals which were immediately exposed to extra muscular exercise after the digitalis injections showed a greater digitalis tolerance than those which did not have to run (tables 1 and 2).

Under our test conditions it was possible to establish a sort of habituation of the guinea‐pigs to digitalis. The strong general effect shown by most of the animals during the first few hours immediately following on the digitalis injections in the first few days gradually subsided.

During weeks the guinea‐pigs could tolerate comparatively large doses of digitalis (half LD 50 doses twice daily). We attribute this to the low cumulative effect of digitotal, the digitalis preparation we used, and to the rapid elimination of digitalis in the guinea‐pig.
On Acclimatization in Connection with Acute Carbon Monoxide Poisonings.
Authors: GORBATOW OLEO , NORO LEO
Published: December 2008

The authors have exposed rats and mice daily to carbon monoxide in contents of 0.25, 0.4, 0.5 and 1 %. Their observations are as follows:

— The test animals became acclimatized to carbon monoxide in contents of 0.25–0.5 % and the tolerance against CO in 8–15 days increased 2–4 times its former value. In 1 % CO only slight acclimatization was observed.

— An intermission of several days in exposure diminished the tolerance. The longer the intermission was the more tolerance (got by acclimatization) the animal lost.
The Form Variations of the Spike Recorded by a Micro‐electrode Applied onto the Mammalian Retina.
Authors: GERNANDT BO
Published: December 2008

Fast recording of the spikes isolated by a micro‐electrode applied onto the cat's retina shows that, as soon as the spikes are

large enough for ananlytical work, they are all alike though varying in size from 0.100–0.300 mV, The form of the spike is illustrated in fig. 1. It suggests that it consists of an optic nerve impulse combined with an electrotonic component from the cell bodies.
Interaction between Acetylcholine and Adenosine Triphosphate in Normal, Curarised and Denervated Muscle
Authors: BUCHTHAL FRITZ , FOLKOW BJØRN
Published: December 2008

Application of adenosine triphosphate (ATP) preceding the intra‐arterial injection of acetylcholine increases the sensitivity of striated amphibian and mammalian muscle to acetylcholine. This sensitization is not specifically connected with the neuromuscular transmission, for there is also in curarised muscle an increase of the mechanical response produced by electrical stimulation after previous application of ATP. This increase is, however, restricted to the actual period of contraction.

In denervated muscle intra‐arterial injection of acetylcholine renders the muscle insensitive to subsequent application of ATP. When small amounts of acetylcholine are applied, the block is only present when ATP is administered through the artery, intramuscular application of this substance still being highly effective in the release of contraction.

Larger amounts of acetylcholine also prevent intramuscularly applied ATP from being active. The electrical excitability remains unaltered.

The threshold for intra‐artefially injected acetylcholine was ound to be ten times higher in winterfrogs than in summer‐frogs. In the former acetylcholine produces a contracture‐like response. Previous application of ATP changes it to a contraction of short duration. When twitches are produced by electrical stimulation during the acetylcholine response, they are enhanced in summerfrogs and reduced in height in winterfrogs.

Intra‐arterial injection of acetylcholine decreases the electrical excitability and changes the strength‐duration curve of muscle for a considerable time after its application. The effect is especially pronounced in denervated muscle. The electrical excitability of denervated muscle is considerably higher than that of curarised muscle, while strength‐duration curves of denervated muscle are unaffected by curarisation. Previous application of ATP does not affect the strength‐duration curve of a muscle.
The Importance of Sodium Ions for the Excretion of Ammonium and Hydrogen Ions in the Urine
Authors: RYBERG CARL
Published: December 2008

The aim of the present work has been to investigate whether the urinary excretion of NH4 and H+ takes place by an exchange with positive ions from the urine. pH in the urine and the excretion of NH4 were investigated under conditions, where the amount of positive ions reaching the distal part of the tubules was reduced. The following results were found:

At high values of the excretion of NHJ, a cation deficiency resulted in a decrease in this quantity.

Simultaneously a very large reduction in the urinary excretion of Na+ and a more moderate decrease in the excretion of the other cations were found.

The pronounced reduction in the urinary excretion of Na+ was absent in the beginning of an acidosis, when the formation of ammonia was small.

The hydrogen ion concentration of the urine varied with the content of Na+ over a considerable range of concentration. When Na+ or K+ were ingested, pH decreased in spite of the increasing diuresis.

The experiments support the idea that NHt and H+ are excreted by exchange with cations from the tubular fluid. It is emphasized that the privileged position apparently occupied by the sodium ion is not necessarily associated with the exchange process itself but may be due to an active transport of this ion from the tubular cells to the interstitial fluid.

The possible effects of an active transport of sodium on the migration of other ions are discussed.
On the Histaminolytic Activity of Skin Extracts
Authors: GBANROTH TRYGVE , NILZÉN ÅKE
Published: December 2008

In the study recorded the present writers have demonstrated a histaminolytic action of extracts prepared from the skins of guinea‐pigs, rabbits, cats, and human subjects.
Interaction of Ergotamine and Carbon Dioxide on Blood Pressure and Respiration
Authors: LILJESTRAND Åke
Published: December 2008

The action of ergotamine on the effect of inhaled carbon dioxide on blood pressure and respiration in the cat has been investigated.

The results indicate that the fall of blood pressure caused by carbon dioxide in the ergotaminized cat is principally due to a central inhibition of the blood pressure regulation, the inhibition being relatively specific to carbon dioxide. The local vasodilating action of the carbon dioxide then appears.

Ergotamine was also found to exert an inhibitory influence on respiratory regulation. It caused a decrease both in the normal ventilation and in the extent of the usual increased ventilation following inhalation of carbon dioxide. This action is interpreted as arising from a diminished sensitivity of the respiratory centre.
The Effect of Essential, Synthetic Amino Acids on the Growth of Rats
Authors: WRETLIND K. A. J.
Published: December 2008

The author has studied the growth of rats which as the sole source of nitrogen had received a mixture of the racemic forms of the 10 essential amino acids, synthetically produced. As nitrogen‐free diet, a mixture containing merely 0.002 % N was used.

On a diet containing 10 % of this amino acid mixture a growth averaging 0.33 ± 0.14 grams per day was obtained.

On a 20 % diet the growth of the rats averaged 0.89 ± 0.15 grams per day.

On the other hand if the rats received 30 and 40 % amino acids in the diet, a decrease in weight, averaging 0.11 ±0.25 and 0.63 ±0.27 grams per day respectively, resulted. Thus, it must be considered that these synthetic amino acids in their racemic forms, contain some toxic matter, but exactly whence it emanates has not yet been ascertained.

The synthesis of the 10 essential amino acids is briefly described.
Renal Excretion of Glycerol
Authors: SVEINSSON SVEIN L.
Published: December 2008

Orientatory investigations were made respecting the renal excretion of glycerol in man.

A method for the splitting of glycerol in biological samples by means of periodic acid is described. The method permits of distinguishing between glycerol and attendant substances which give colour reactions similar to those produced by glycerol.

At plasma‐glycerol concentrations above 30 mg% the excretion percentage has, in accordance with Holst, been found to be independent of the concentration in plasma and of diuresis.

At lower plasma‐glycerol concentrations the excretion percentage decreases with decreasing concentration in plasma.

These findings respecting the excretion are explained by assuming that glycerol is a threshold substance with low Tm (concentration threshold about 10 mg%), the excretion of which at higher concentrations of glycerol in plasma is, however, completely governed by a passive retrodiffusion of glycerol in the proximal tubuli.

Through this conception of the glycerol excretion Holst's findings can be brought into harmony with the theory of phosphorylation as part of the process of active tubular reabsorption.
The Individual Variability in Respiration. Elucidated by Determination of the Excitability of the Respiratory Centre
Authors: ØSTERGAARD TORSTEN
Published: December 2008

Individual variations in the excitability of the respiratory centre are considerable. Numerically expressed — by a special method — the excitability coefficients of 36 patients (convalescents after melancholia) were found to vary from 12.2 to 34.4, and from 11.6 to 41.3, in 26 normal subjects. Correspondingly, pronounced individual variations were ascertained in respect of rate and depth of respiration, of ventilation, and of CO2 tension in alveolar air — in the cases of 26 normal subjects and 36 patients.
The Amount of Hemoglobin and the Blood Volume in Relation to the Pulse Rate and Cardiac Volume During Rest
Authors: KJELLBERG SVEN ROLAND , RUDHE ULF , SJÖSTRAND TORGNY
Published: December 2008

In a material composed of children, women and men, including athletically trained men and women, the amount of hemoglobin and the blood volume estimated on the basis of the amount of hemoglobin have been placed in relation to the pulse rate, to the pulse rate/standard metabolism ratio estimated by and to the heart volume, determined roentgenologically on a subject in prone position.

There is a clear correlation between the amount of hemoglobin and the pulse rate during rest. The correlation is brought out still more clearly if the amount of hemoglobin is pulse rate/standard metabolism placed in relation to the ratio which may be taken as a reference standard for the stroke volume during rest.

The amount of hemoglobin and, to a still somewhat higher degree, the blood volume show a very close correlation to the heart volume determined roentgenological^ on a subject in prone position. The correlation coefficient for children, women and men is about 0.90. Broadly speaking, the figures for children, women and men, the athletically trained included, fall along the same regression line.

The results serve to explain in a simple way the varying values for the resting pulse rate and heart volume, found in children and adults, women and men, and the physically trained and the untrained, respectively. It seems thus that the larger heart volume in healthy, athletically trained persons could be entirely attributed to the increased blood volume in connection with physical training.

The regulation of the blood distribution (in heart, lungs and systemic circulation) is discussed with due regard to the results obtained.

The costs of the investigation have been partly defrayed by a grant from the Therese and Johan Andersson Memorial Fund.
Increase of the Amount of Hemoglobin and Blood Volume in Connection with Physical Training
Authors: KJELLBERG SVEN ROLAND , RUDHE ULF , SJÖSTRAND TORGNY
Published: December 2008

In the present paper we report on an investigation in which the amount of hemoglobin determined after the method of SJÖSTRAND (1948) in a number of athletically trained men and women has been compared with that in an average group of the respective sexes.

The athletically trained men and women showed considerably higher amounts of hemoglobin and blood volumes than the average material. On the whole, the best trained men deviated by 41%, and the women by 44% from the reference material.

In three men and one woman the amount of hemoglobin was determined just before and immediately after a skiing tour in the mountains. The figures were 10–19 per cent higher after the training than before.

In a patient who had been confined to bed for a considerable length of time (owing to fracture of the leg) the amount of hemoglobin was determined repeatedly. It showed a successive decrease, amounting at its maximum to 15 per cent of. the original figure. The amount of hemoglobin and blood volume seems accordingly to vary with the degree of physical training.

The costs of the investigation have in part been defrayed by a grant from the Therese and Johan Andersson Memorial Fund.
The Amount of Hemoglobin (Blood Volume) in Relation to the Pulse Rate and Heart Volume During Work
Authors: KJELLBERG SVEN ROLAND , RUDHE ULF , SJÖSTRAND TORGNY
Published: December 2008

By determination of the total amount of hemoglobin and the blood volume estimated on that basis, in a material of children, women and men, including athletes a very marked correlation, + 0.82 and + 0.90, respectively, was found between the amount of hemoglobin and the pulse rate during work—or the work at which the pulse reaches a level of about 170 beats per minute. This indicates that there is a close correlation between the total blood volume and the stroke volume during work.

In 12 persons (among the adults) with different amounts of hemoglobin, the heart volume was determined during the performance of a varying amount of work on the bicycle ergometer.

In one group of the tested persons the heart volume diminished only slightly up to a pulse rate of about 150 beats per minute, but afterwards more rapidly. In another group the heart volume diminished in proportion to the increase of the pulse rate.

The first‐mentioned group consisted of individuals of average build, the latter of men of more leptosomatic type, with a small amount of hemoglobin in comparison to body height.

When the movements of the left ventricular and of the aortic walls were recorded during the different cardiac periods with electrokymography, it was found that the systolic emptying of the left ventricle greatly increased during work, although the heart volume remained unchanged or was actually less than during rest. It was also shown with the same technique that there was a parallelism between the change in the heart volume during work and the filling of the left ventricle.

There seems to be no direct correlation between the heart volume and the stroke volume in the same individual, an assumption, which might be expected if the stroke volume were regulated in accordance with Starling's heart law. These findings are discussed and a new hypothesis in regard to the regulation of the blood circulation and the blood distribution is advanced in order to explain the results found in normal man.
The Distribution of Sympathin N and Sympathin A in Spleen and Splenic Nerves of Cattle
Authors: von EULER U. S.
Published: December 2008

Extracts of splenic nerves and spleen contain small but definite amounts of adrenaline (sympathin A) in addition to noradrenaline (sympathin N) as assayed by differential tests on cat's blood pressure and hen's rectal caecum.

This finding constitutes the base for a dual adrenergic nerve transmission, as indicated by remote effects after nerve stimulation (CANNON and KOSENBLUETH).

Extracts of spleen contained on an average adrenaline to 7.2 per cent of the total catechols and extracts of splenic nerves significantly less, on an average 2.2 per cent.

The results are in favour of the assumption that the noradrenaline in the nerves is partly methylated, this process being more intense in the peripheral parts of the nerves.
Some Remarks on the Determination of Histamine with Special Reference to Horse Blood
Authors: SCHMITERLÖW CARL G.
Published: December 2008

When treating histidine solutions according to BARSOTTM‐GADDUM‐CODB'S histamine extraction method it has been found that a small part of the histidine will be transformed into histamine. This is in accordance with the findings of ÅKERBLOM (1941).

A simple method of extracting histamine from blood is described. To one volume of blood two volumes of ethyl alcohol is added together with H2SO4 sufficient to give the mixture a pH of about 4. The mixture is allowed to stand for 11/2 hour. After filtration and washing of the precipitate with alcohol the total filtrate is evaporated to a small volume in vacuo. After dilution with water and adjusting the pH to neutral the extract is ready for biological testing.

Using this extraction method histamine was quantitatively recovered from water solutions of histamine and also from histamine added to horse blood.

The amount of histamine in horse blood has been determined both according to CODE'S method and to the method described in this paper. Using CODE'S method a mean value of about 0.18 μg histamine per ml blood (expressed as dihydrochloride) was found whereas the other method gave a mean value of 0.065 μ per ml. Some part of the histamine obtained with CODE'S method may derive from the histidine in hemoglobin, decarboxylated during the extraction procedure. When extracting pure hemoglobin solutions according to CODE'S method the final extracts contain histamine in a concentration which corresponds to the above‐mentioned difference.
The Significance of Ketone Bodies in Fat Metabolism
Authors: GAMMELTOFT ALLAN
Published: December 2008

In experiments on starving human subjects it has been demonstrated that the ketone concentration in the venous blood is lower than in the arterial blood. This arterio‐venous ketone difference increases markedly with increase in the blood ketone concentration. From the third day of starvation the arterio‐venous difference reaches a value of about 7 mg per cent indicating that the participation of the peripheral tissues in the fat metabolism is practically exclusively an oxidation of ketone bodies. This assumption is confirmed by simultaneous determinations of the arterio‐venous oxygen difference. Determinations of this kind on human subjects have been supolemented by corresponding determinations on dogs poisoned with phlorhizine.

LUNDSGAARD'S suggestion that the fat metabolism always follows the scheme: partial oxidation of fatty acids in the liver to ketone, bodies, followed by oxidation of the ketones in the peripheral tissues is discussed. It is concluded that though this type of fat metabolism is found in humans already from the third to fourth day of starvation it cannot be considered the normal type of fat metabolism.