bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of Oxygen Tension on the Surface of the Cerebral Cortex of the Cat during Hyperoxia and Hypoxia
Authors: Ingvar David H. , Lubbers Dietrich W. , Siesjö Bo 
Published: December 2008

AbstractThe oxygen tension on the surface of the intact cerebral cortex of the cat was recorded continuously by means of a membrane covered platinum cathode (Lübbersand Ockenga1958). The stability of the electrode permitted an interpretation of results from different experiments in relative terms. The influence upon the cortical PO2, of high and low oxygen concentrations in the inspired air was studied. In ordinary hyperoxia only a moderate increase of cortical PO2, was found. In post‐hypoxic hyperoxia the cortical values reached values about 3 times as high. The difference found is interpreted as due to so called reactive hyperemia in the post‐hypoxic state.
Muscle Training by Static, Concentric and Eccentric Contractions
Authors: Petersen Flemming Bonde 
Published: December 2008

AbstractIsometric strength of the elbow flexors and the knee extensors was measured by a strain‐gauge dynamometer constructed according to Darcus (1953). The accuracy of this dynamometer was found to be ± 1–3 per cent. Seventeen young female and seventeen young male subjects underwent a training period of from 20 to 36 days. Their training constituted the performance of one of the following forms of exercise: 1 daily maximum isometric contraction, 10 daily maximum isometric contractions, 10 daily eccentric muscular contractions or 15 min of daily heavy dynamic work (riding a bicycle ergometer). The effect on the isometric strength and endurance of the trained muscle groups was measured and compared to a control group of 7 females and 6 males, who received no specific training, It was found that 1 daily maximum isometric contraction had no effect on the isometric strength of the muscles, 10 daily maximum isometric contractions had a tendency to increase the isometric strength of the muscles, while 10 daily maximum eccentric contractions had no measurable effect on isometric muscle strength. Heavy dynamic work increased the isometric strength of the muscles by 12 per cent in the females and 23 per cent in the males. There was no measurable effect on endurance to sustained isometric contractions consequent to any of the training programs. Training of muscles on one side did not modify the strength of the contralateral muscle groups.
Intermittent Muscular Work
Authors: ÅStrand Irma , ÅStrand Per‐Olof , Christensen Erik Hohwü , Hedman Rune 
Published: December 2008

AbstractThe physiological effect of rest pauses on a non‐steady state work (2,160 kpm/min) was studied. A physically well trained subject performed in one hour a total amount of 64,800 kpm on a bicycle ergometer by intermittent work with 0.5, 1, 2 or 3 min periods of work and rest. Total O2 intake, total pulmonary ventilation, total number of heart beats and blood lactic acid concentration during the work hour and during recovery were determined. It was found that the heavy work when split into short periods of work and rest (of 0.5 or 1 min duration) was transformed to a submaximal load on circulation and respiration and was well tolerated during one hour. With longer periods (of 2 or 3 min duration) the work output got close to the upper limit of performance and could be fulfilled only with the utmost strain. These findings are discussed from a physiological and practical point of view. In order to explain the low lactic acid values during the short periods of work and rest it was proposed that the myohemoglobin has an important function as an oxygen store during short spells of heavy muscular work.
Myohemoglobin as an Oxygen‐Store in Man
Authors: ÅStrand Irma , ÅStrand Per‐Olof , Christensen Erik Hohwü , Hedman Rune 
Published: December 2008

AbstractThe aim of the present research was to investigate further the possible r81e of myohemoglobin as an oxygen‐store during the initial stage of muscular work. One subject worked intermittently with a work load of 2,520 kpm/min with varied duration of work and rest pauses on a bicycle ergometer. A highly significant difference in the blood lactic acid concentration during the experimental time of 30 min was found, at work with short work periods (10 sec, lactic acid concentration about 10–20 mg per 100 ml) compared with relative long ones (60 sec, lactic acid concentration 110–140 mg per 100 ml). The conclusion was drawn that the first type of work is performed aerobically. The calculated oxygen demand, during the work period of 10 sec, however, does not correspond to the measured oxygen intake. A deficit of about 0.43 1 O2 for each period of work will occur. It was suggested that this amount of 0.43 1 O2 is supplied to the working muscle mainly from oxymyo‐hemoglobin. This store function of myohemoglobin is discussed in relation to the present findings and to the results mentioned in the literature.
On the Specificity of the RUM Like Joint Receptors
Authors: Eklund G. , Skoglund S. 
Published: December 2008

AbstractThe response pattern of Ruffini like receptors has been studied in some 60 knee joint capsule preparations, which in a Tyrode bath were exposed to a linear increase of tension. The response pattern was also studied while applying an additional tension increase at angles to the linear one. From the findings it was concluded that the sensitivity bands displayed by the sense organs in situ are only a reflection of tension alterations in the capsule and not of specific end organ properties.
Dynamic Elasticity in the Initial Phase of an Isotonic Twitch
Authors: Buchthal F. , Rosenfalck P. 
Published: December 2008

AbstractA method is described which allows a continuous determination of the elastic and viscous component of the dynamic stiffness of isolated frog muscle fibres in vibration experiments. Elastic and viscous stiffness increased gradually in the initial phase of preloaded isotonic twitches. The increase started already within the mechanical latent period. Within 25 per cent of the time to maximum shortening elastic stiffness increased by 100 per cent and viscous stiffness by 50 per cent. In slightly stretched fibres, at the length in the body, the increase in dynamic stiffness during tetanic contraction was identical with that found in a twitch. In highly stretched fibres dynamic stiffness in a tetanus exceeded that of a twitch, presumably due to the redistribution of load between the contractile substance and the sarcolemma. The increase in dynamic stiffness during a twitch immediately after a prolonged tetanus was markedly lower than in a twitch performed before the tetanus. The contributions to the dynamic stiffness from the parallel elastic, the series elastic and the contractile component were evaluated. Although the periodical deformations were essentially confined to the series elastic component, the dynamic elastic properties give information about the contractile substance as the series elastic component mainly represents the elasticity of the contractile material.
Comparison of the Effect of Ethanol and Malonate on the Respiration of Rat Brain Cortex Slices
Authors: Wallgren Henrik 
Published: December 2008

AbstractEthanol and malonate both reduce the respiration of stimulated cerebral cortex tissue at concentrations which do not depress the oxygen uptake of unstimulated tissue. A study was made of the effects of these compounds added separately or simultaneously at low concentrations to a phosphate‐glucose saline. Within the concentration ranges employed (malonate 10‐4 ‐ 8 times 10‐4M, ethanol 8.7 times 10‐2 ‐ 1.96 times 10‐1M), the only effect on unstimulated tissue was a slight increase in respiration in presence of ethanol. In electrically stimulated tissue, malonate and ethanol both diminished the respiration. When the inhibitors were present simultaneously, the effect of one of them only was obtained, i. e. of that inhibitor having greater action at the particular concentration. This lack of synergism was taken as evidence for independent inhibitory action of ethanol and malonate.
The Effect of Body Position on the Circulation at Rest and During Exercise, with Special Reference to the Influence on the Stroke Volume
Authors: Bevegård S. , Holmgren A. , Jonsson B. 
Published: December 2008

AbstractIn 10 healthy, adult, male subjects the hemodynamics have been studied by the aid of heart catheterization at rest and during work both in supine and sitting positions. The cardiac output was on the average 2.2 1/min less in the sitting than in the supine position, both at rest and during exercise. In the supine position, the stroke volume was constant at rest and during exercise. In the sitting position, the stroke volume at rest was 40 per cent smaller than in the supine. It increased considerably with mild work, but not significantly with an even heavier work load. It never reached the values obtained in the supine position, even during heavy work. The arterio‐venous oxygen difference was larger in the sitting than in the supine position, both at rest and during work. During heavy work, the oxygen transport per heart beat was the same in the supine and the sitting positions, and the physical working capacity (work performed per heart beat) was also of the same order.
Circulatory Data in Normal Subjects at Rest and During Exercise in Recumbent Position, with Special Reference to the Stroke Volume at Different Work Intensities
Authors: Holmgren A. , Jonsson B. , Sjöstrand T. 
Published: December 2008

AbstractRight heart catheterization has been performed in 18 healthy subjects, 14 males and 4 females, including estimation of cardio‐vascular pressures and cardiac output at rest and during different intensities of exercise in recumbent position. During exercise the cardiac output increased linearly with the oxygen uptake. The increase of the arterio‐venous oxygen difference in relation to the work load or the pulse rate was higher in the males than in the females. With change from rest to work the stroke volume increased slightly but significantly in the males. By increasing work load it successively decreased to the size at rest. There was a high correlation between the stroke volume on one hand and the work performed at pulse rate 170, the heart volume, and the blood volume on the other. The mean pressure in the pulmonary artery was 5 mm Hg higher during exercise than at rest but was constant at different work loads. The end‐diastolic pressure in the right ventricle and the mean pulmonary venous pressure (PC V‐pressure) did not change significantly with the increase in pulse rate.
On the Role of Monoamine Oxidase for the Inactivation of Dopamine in Brain
Authors: ROSENGREN EVALD 
Published: December 2008

AbstractEvidence is presented that monoamine oxidase is involved in the metabolism of dopamine in brain. Thus 3,4‐dihydroxyphenylacetic acid has been demonstrated to occur in the brains of three species investigated, including man. That this acid was derived from dopamine after oxidative deamination seemed probable as it was found to be localized in the same areas of the brain as dopamine and it disappeared after inhibition of monoamine oxidase with iproniazid. The capacity of this enzyme in brain seemed to be sufficient for the plausible inactivation rate of dopamine in this tissue.
In Vitro Release of Histamine from Cat Skin by Compound 48/80
Authors: Westerholm Barbro 
Published: December 2008

AbstractWesterholm, B. In vitro release of histamine from cat skin by compound 48/80.A method for studying histamine releasing activity is described. Chopped cat skin was incubated with liberator and the histamine released was assayed on guinea‐pig ileum. The mechanism of action of compound 48/80 on this preparation was studied. It was shown that histamine release by 48/80 was dependent on time, concentration, temperature and pH. There were temperature and pH optima, though they were not well defined with the doses used. The release could be blocked by certain enzyme inhibitors as the amino group reagent, ninhydrin, and the sulfhydryl group blocking substance, allicin. The observations are considered to support the hypothesis that 48/80 acts by means of an enzyme mechanism.
The Biological Half‐Life of Bromide Ions in Human Blood
Authors: Söremark Rune 
Published: December 2008

AbstractThe biological half‐life of bromide ions in human blood was studied in 10 human subjects. The subjects were healthy students about 20 years old. The radioactive isotope, Br82, was given orally in form of NH4Br in water solution. Venous blood samples were drawn from the subjects twice a day. The biological half‐life of bromide ions in the blood was found to be about 12 days. The bromide ratio red blood cells/serum was found to be about 0.45. This was calculated by using the mean from ten hematocrit values obtained from every person. No bromide was found to be incorporated in fat, extracted from plasma and hemolysed blood cells by ether. Neither was there found any bromide incorporated in blood proteins. This was determined by precipitation with trichloroacetic acid, tannic acid, and phosphotungstic acid and anion exchanger, and paper electrophoresis.
Effect of Reserpine on the Storage of Catechol Amines in Brain and Other Tissues
Authors: Bertler ÅKe 
Published: December 2008

AbstractBertler Å. Effect of reserpine on the storage of catechol amines in brain and other tissues.The effect of reserpine on the metabolism of dopamine and noradrenaline in tissues has been studied. Dopamine was found to be depleted from the brain at a higher rate than noradrenaline; dopamine decreased to 50 per cent of the normal level in 15 min while the corresponding time interval for noradrenaline was 45 min. The dopamine in the peripheral tissues of the sheep was found to be only slightly lowered within 13 hours, after administration of 2 and 4 mg reserpine per kg whereas the dopamine of the brains were reduced to insignificant amounts. In this respect it behaved in the same way as 5‐hydroxytryptamine (5‐HT). The rate of disappearance of catechol amines after reserpine is suggested to be dependent on the rate of turnover of the amines. The principal effect of reserpine on the tissue catechol amines and 5‐HT is supposed to be due to an interaction of the active transport of the amines into the storage sites. The results of the investigation indicate that the drug does not interfere with the decarboxylation of dihydroxyphenylalanine and 5‐hydroxytryptophan.
Occurrence and Localization of Catechol Amines in the Human Brain
Authors: Bertler ÅKe 
Published: December 2008

AbstractBertlerÅ.,Occurrence and localization of catechol amines in the human brain.The content of noradrenaline, dopamine and 5‐hydroxytryptamine (5‐HT) in various structures of the human brain has been investigated. Noradrenaline in rather high concentrations was found in the anterior and middle portion of the hypothalamus, and lower levels were recorded in structures of the mesencephalon and the floor of the 4th ventricle. Dopamine showed a very strict localization to structures which are involved in the extra‐pyramidal system, i. e. the basal ganglia and the substantia nigra suggesting that it may be involved in the function of this system. Relatively high concentrations of 5‐HT were found in the hypothalamus, the medulla oblongata, the corpus striatum and the thalamus.
Brief Cyclic Variations in Some Sexual Functions of the Male Rabbit
Authors: Degerman G. , Kihlström J. E. 
Published: December 2008

AbstractG. Degerman J. E. Kihlström. Brief cyclic variations in some sexual functions of the male rabbit.It has been demonstrated by means of two different statistical methods that at least two sexual functions of male rabbits, the volumes of daily ejaculates and the intensity of the sexual drive, are subjected to cyclic variations. The length of the cycle varies individually from 3 to 6 days, and is in some individuals superimposed by a longer period.
Influence of Noradrenaline on Spinal Interneuron Activity
Authors: Skoglund C. R. 
Published: December 2008

AbstractSkoglundC. R.Influence of noradrenaline on spinal interneuron activity.The effects of intra‐arterial and intravenous injections of noradrenaline on spinal interneurons have been studied on decapitate, curarized cats by means of intracellular technique. The most common effect, observed at a threshold dose of 1 μg per kg bodyweight, was an increase in excitability. Interneuron responses to single afferent volleys were facilitated, a typical effect being transformation of single spike responses into repetitive discharges. In the absence of any induced afferent stimulation noradrenaline injections were observed to set up discharges in initially silent cells and to cause an increase in frequency of prevailing activity, sometimes followed by a decrease. An initial decrease in excitability was only occasionally seen.
Effects of Intravenous Infusions of Adrenaline and Noradrenaline on Certain Psychological and Physiological Functions
Authors: Frankenhaeuser Marianne , Järpe Gundla , Matell G. 
Published: December 2008

AbstractFrankenhaeuser M., G. Jarpe G. Matell. Effects of intravenous infusions of adrenaline and noradrenaline on certain psychological and physiological functions.Effects of intravenously infused 1‐adrenaline (average dose 14.9 μg/min, average infusion time 34.7 min) and 1‐noradrenaline (average dose 16.2 μg/min, average infusion time 36.8 min) were examined by objective methods in six subjects. The psychological tasks were chosen so as to represent different functional areas. Heart rate and arterial blood pressure were continuously recorded, and excretion of urinary catechols before, during and after infusions was determined. Both drugs produced subjective symptoms (mental and physiological), and these were more pronounced and more frequent for adrenaline. Marked changes in heart rate and arterial pressure were recorded during the infusions. The stress involved in performing the psychological tasks also caused a pronounced increase in heart rate, arterial pressure and the urinary excretion of catechols. Performance did not differ significantly from that during the infusion of Ringer's solution. These results were tentatively interpreted to indicate that an increased alertness accompanying the emotional changes produced by the drugs may act to counterbalance other, unfavourable effects on performance.
Percutaneous Puncture of the Radial Artery with a Multi‐Purpose Teflon Catheter for Indwelling Use
Authors: Barr Per‐Olof 
Published: December 2008

AbstractBarr P.‐O. Percutaneous puncture of the radial artery with a multipurpose Teflon catheter for indwelling use.A Teflon catheter assembly is described, which was designed for percutaneous insertion and indwelling use in the radial artery, and in other superficial blood vessels with calibers of a similar order of magnitude. The advantages of the instrument, which may also be used for percutaneous puncture of other superficial tissues and organs, are reported and discussed, especially with regard to the preferential choice of the radial artery for arterial punctures.
Effect of Reserpine on the Storage of New‐formed Catecholamines in the Adrenal Medulla
Authors: Bertler ÅKe , Hillarp Nils‐Åke , Rosengren Evald 
Published: December 2008

AbstractWhen L‐dopa (100 mg/kg body wt.) was given i.v. to reserpinized (5 mg/kg) rabbits, appreciable amounts of dopamine and noradrenaline rapidly formed in the adrenal medulla. The results support the view that reserpine does not — at least not to a great extent — interfere directly with the decarboxylating and β‐hydroxylating steps in the amine synthesis. To a great extent, however, the drug prevented the new‐formed amines from being incorporated in the storage granules, an incorporation which in normal animals is a very rapid and efficient process. It seems reasonable to assume that reserpine in some way blocks the process of monoamine storage. This may well be the main site of action of the drug.
The Role of the Adrenals on the Mucosal Mast Cells and Tissue Eosinophils in the Gastric Wall of Rat
Authors: Räsänen Toimi 
Published: December 2008

AbstractThe effect of ACTH on the mucosal mast cells and tissue eosinophils in the gastric wall of adrenalectomized and intact rats was studied. In intact rats, ACTH caused almost complete degranulation of the mucosal mast cells and a highly significant fall in tissue eosinophilia. Its degranulating effect on the mucosal mast cells and its tissue eosinopenic effect were inhibited after adrenalectomy. Adrenalectomy alone caused a slight increase in both these cell types in the gastric mucosa. The significance of mast cells as a mucosal histamine depot and its possible primary role as secretory stimulant of the parenchyma and secondary role in causing reduction of tissue eosinophilia is discussed.
A Self‐Recording Electronic Osmometer for Quick, Direct Measurement of Colloid Osmotic Pressure in Small Samples1
Authors: Hansen A. Tybjaerg 
Published: December 2008

AbstractA self‐recording electronic osmometer for clinico‐physiological use is described. It is a further development of an osmometer described earlier by the author. It is based on the passive counter‐pressure principle and as such representing a return to the principle that was first applied in osmotic pressure measurements. The general principles for the measuring of osmotic pressure and the special requirements to be fulfilled if quick performance is to be obtained are discussed. The importance of the diffusion phenomena in this context has been emphasized and experimentally elucidated. The sample of plasma or serum which is required, is from 0.02 to 0.1 ml. Ten to 15 measurements can be performed per hour. The confidence limits for one measurement are ± 0.5 mm Hg. at the 5% level. Commercially available cellulose membranes are used. No stopcocks are employed. Stainless steel is used for all parts in contact with membrane and sample. The possible usefulness of the osmometer for investigation of the reflection coefficient of permeating particles and for testing membranes is pointed out. Also the possible use in investigations of active trans port problems in connection with organic membranes is hinted at. Finally it is mentioned that the red blood cells under certain circumstances will influence the osmotic pressure.
A Comparison of the Distribution of Radioactive Fluorine and Calcium by Use of Double‐Isotope Autoradiography
Authors: Appelgren Lars‐Erik , Ericsson Yngve , Ullberg Sven 
Published: December 2008

AbstractThe autoradiographic distribution picture has been compared in whole pregnant mice and young rats at short intervals after the injection of fluorine (NaF18) and calcium (Ca45Cl2). The isotopes were injected intravenously on the same animal and selective registration of F18and Ca45was made utilizing the great difference in decay rates. Both isotopes, especially Ca45, were rapidly taken up from the blood. F18accumulated more rapidly and selectively in hard tissues while Ca45was taken up in appreciable amounts in some soft tissues. The distribution pattern in bone and in dentine was very similar for F18and Ca48. F18was taken up in proportionately low concentration in the calcifying molar enamel. Ca45but not F18was taken up in the cartilage of young animals.A remarkably high accumulation of Ca45was seen in some groups of striated muscles. These muscle groups may be those which were contracted when the lightly anesthetized animal was sacrificed by immersion in the freezing mixture. The dominating excretory organ for F18was the kidney while high concentrations of Ca45appeared in the mucosa and contents of the small intestine.