bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Digestion and Absorption of Lipoperoxides
Authors: Glavind J. , Tryding N. 
Published: December 2008

AbstractThe purpose of the work was to study the fate of orally ingested peroxides. Lipoperoxides were given by mouth to rats with cannulated thoracic duct. No lipoperoxide could be found in the lymph. Pancreatic juice, bile, and lymph were shaken with lipoperoxides at suitable temperature and pH. At intervals free fatty acids, total lipoperoxide, and, after chromatographic separation on alumina, peroxide‐containing esters and peroxide‐containing free fatty acids were determined. Pancreatic juice splits lipoperoxides with the formation of peroxide‐containing fatty acids, and generally also produces a decrease of total lipoperoxide. Bile and lymph alone have no effect on lipoperoxides. The results suggest that the essential site of the destruction of the lipoperoxides ingested with the food is the intestinal mucosa.
A Colorimetric Method for the Determination of Calcium in Blood Serum
Authors: Gran Fredrik C. 
Published: December 2008

AbstractA colorimetric method is described allowing convenient and rapid estimation of 5–15 μg Ca in 0.1 ml of blood serum. N‐hydroxy‐naphtalene‐1,8‐dicar‐boxylic acid imide forms an insoluble salt with Ca, which is brought into solution by the addition of ethylene diamine tetra‐acetic acid in excess. N‐hydroxy‐naphtalene‐1,8‐dicarboxylic acid imide has an absorption maximum at 338 mμ in alkaline solution; the optical density of the EDTA solution is therefore measured at this wavelength. Two moles of N‐hydroxy‐naphtalene‐1,8‐dicarboxylic acid imide will be equivalent to one mole of Ca. Tartaric acid, low concentrations of citric acid, phosphate, magnesium, zinc, and ferrous or ferric ions will not interfere in the determinations of Ca by this method. Higher concentrations of citric acid as well as the presence of manganese, strontium, and barium, are harmful and must be avoided.
Excretion of Intravenously Injected Solid Particles in Bile
Authors: Juhlin Lennart 
Published: December 2008

AbstractSpherical hydrophilic par: ticles of methyl methacrylate marked with a fluorescent colour were injected i. v. in rabbits, and their concentration in blood and bile was estimated during the following hours. Three sizes of particles were used. After injection of 192 mg particles ranging in diameter from 0.02 to 0.11 μ, particles appeared in the bile in a concentration of 0.05‐0.40 mg/ml during the first minutes after i. v. injection. A relative blockade of the R. E. S. by pretreatment with nonfluores‐cent particles decreased the rate of clearance of the particles from the blood. This increase in particles in blood was not accompanied by a corresponding increase in the bile; instead there was a tendency to a decrease in biliary particle excretion. There was almost no biliary excretion of 0.06‐0.14 μ particles. The lowest detectable concentration of these particles is 0.004 mg/ml bile. Particles 0.2‐0.8 μ in diameter (detectable in amounts over 0.04 mg/ml) could not be found in the bile even with doses up to 1,200 mg. The route of passage of particles to the bile is discussed.
A Comparison of Mast‐Cell Reactions in the Rat, Hamster and Guinea Pig
Authors: Boréus Lars Olof 
Published: December 2008

AbstractParallel in vitro experiments on the mesenterial mast cells were carried out in the rat, hamster and guinea pig. Incubation of mesentery in small, rising concentrations (0.1–100 μg/ml) of compound 48/80, lecithinase A and decylamine caused proportional degrees of “disruption” of the rat and hamster mast cells. pH curves and experiments with enzyme inhibitors gave the same results in the rat and hamster and suggested that, in these two species, the disruption caused by compound 48/80 and lecithinase A involves a similar, enzymatic mechanism, whereas the effect of decylamine is non‐enzymatic. The guinea‐pig mast cells reacted with dissolution and disappearance (but not with the uniform disruption seen in the rat and hamster) upon incubation with decylamine and lecithinase A. However, high doses and a prolonged incubation time was needed for maximal effect and enzyme inhibitors could not block it. It is concluded that the effects on guinea‐pig mast cells was a non‐enzymatic lysis of the cell membrane. Compound 48/80 was without effect on the mast cells of the guinea‐pig. The resistance to hypotonic solutions was about the same in all three species but the “disruption” of the rat and hamster mast cells occurred much faster than the “disappearance” of guinea‐pig mast cells. Provided a sufficient reaction time is allowed, this “disappearance” reaction is the best way of evaluating mast‐cell reactions in the guinea pig.
Functional Localization as an Aid to Implantation of Permanent Electrodes into the Hypothalamus of Horned Goats
Authors: Anderson B. , Persson N. , Ström L. 
Published: December 2008

AbstractAnderson, B., N. Persson and L. Ström. Functional localization as an aid to implantation of permanent electrodes into the hypothalamus of horned goats.A method is described for implantation of permanent platinum iridium electrodes into the brain stem of horned goats. The final fixation of the electrodes is preceded by an acute stimulation experiment performed according to the technique of Hess. In this manner a satisfactory functional localization is secured.
Oxygen Intake and Thermal Balance in Naked Young Men during Rest and Sleep at Various Ambient Temperatures
Authors: Andersen K. Lange , Hellström B. 
Published: December 2008

AbstractAndersen, K. L. and B. Hellström. Oxygen intake and thermal balance in naked young men during rest and sleep at various ambient temperatures.—The metabolic and thermal responses of three young men were investigated when resting or sleeping naked for eight hours at various ambient temperatures between 30 and 20° C. The results revealed that the naked men have a rather narrow thermal comfort zone. Exposure to 30 °C was felt to be uncomfortably warm. At 20° C two of the three subjects gave up after four hours exposure because they were too cold. The oxygen intake varied from 3.5 to 4.5 ml/min/kg body weight, and no metabolic elevation was observed at an ambient temperature of 25° C and higher. The oxygen intake at 20° C was markedly increased. Our data show that the critical temperature for a naked man lying stationary is about 25° C. The skin temperature is a function of the environmental temperature. After 2–3 hours' initial fall, the rectal temperatures reached a steady state in two of the subjects, at all ambient temperatures, but dropped consistently in one subject at the lowest air temperatures, showing that this subject met a cold situation by drawing on his stored body heat in addition to increasing the body insulation. This mechanism has been seen in many cold habituated people, and our findings indicate that the difference between cold‐exposed and non‐acclimatized people is quantitative rather than qualitative.
On the Reflex Effects from the Knee Joint of the Cat
Authors: Ekholm J. , Eklund G. , Skoglund S. 
Published: December 2008

AbstractThe reflex effects on extensors and flexors of the knee joint have been studied in response to various stimulations of the knee joint capsule and the medial collateral ligament. The joint receptors were activated by increasing the intra‐articular pressure or by pinching the anterior aspect of the knee joint capsule. This stimulation caused an inhibition of the knee extensors and a facilitation of the knee flexors in both the decerebrated and decerebrated and spinalized preparation. Activation of the receptors in the medial collateral ligament was likewise found to produce a flexor facilitation in the decerebrated and spinalized animal, effects that sometimes could be produced even in the decerebrated animal.
Intra‐Articular Knee Joint Temperature Variations in Response to Cooling and Heating of the Skin in the Cat
Authors: Ekholm Jan , Skoglund Sten 
Published: December 2008

AbstractThe intra‐articular temperature was measured in the knee joint of the cat during cooling and heating of the anteriomedial aspect of the thigh. Cooling produced a transient increase of the intra‐articular temperature before it began to fall, and rewarming gave a transient increased fall of the intra‐articular temperature before it began to rise. These paradoxical phenomena could be produced in the intact animals and in animals with partially denervated knee joints. In a flayed limb no paradoxical temperature phenomena could be produced, neither could they be set up in a limb deprived of its sympathetic outflow by unilateral lumbar sympathectomy. The blood pressure was found to increase and decrease transiently during cooling and heating respectively. The variations of the pressure occurred almost simultaneously with the paradoxical temperature phenomena in the joint. These blood pressure variations can, however, only be part of the explanation of the paradoxical effects seen, because cooling the intact limb which increases the blood pressure, was not found to produce the phenomenon in the contralateral sympathectomized side. The mechanisms behind the paradoxical phenomena are discussed and it is concluded that temperature variations as measure of bloodflow variations in response to cooling and heating can only be used when they vary in the opposite direction to the stimuli applied.
Effects of Motor Inactivation on the Chemical Sensitivity of Skeletal Muscle
Authors: Johns T. R. , Thesleff S. 
Published: December 2008

AbstractJohns T. R. and S. Thesleff. Effects of motor inactivation on the chemical sensitivity of skeletal muscle.In order to determine whether the lack of motor nerve impulses, without denervation per se, alters the chemically sensitive area in skeletal muscle, the size of the ACh‐sensitive areas in muscle fibres of cat tenuissimus were measured after isolation of the motor neurones by severance of the dorsal roots below a lower lumbar cord transection. The sensitivity of the individual muscle fibre to ACh was determined by iontophoretic micro‐application of the drug, and by intracellular recording of the potential change. The frequency of miniature end‐plate potentials, their amplitude, and their time course, were relatively unaffected by the isolation procedure. The procedure also caused little increase in the size of the ACh‐sensitive surface. Therefore, inactivation per se did not alter the chemically sensitive area.
Respiration and State of Wakefulness in Normals, Studied by Spirography, Capnography and EEG: A preliminary report
Authors: Bülow Knut , Ingvar David H. 
Published: December 2008

AbstractBülow K. and D. H. Ingvar. Respiration and state of wakefulness. studied by spirography, capnography and EEG.In sixteen normal subjects the relation between the state of wakefulness and the respiration was studied by recording continuously the ventilation (spirography), the alveolar carbon dioxide tension (capnography) and the EEG. Records were obtained in the resting state awake, in drowsiness and, in nine of the subjects, in sleep and during arousal. It was confirmed that ventilation decreases and that the alveolar carbon dioxide tension increases in sleep (Magnussen 1944). When the EEG showed a stable pattern of e. g. alpha‐activity, or sleep waves, the breath to breath variations in ventilation and alveolar carbon dioxide tension were small at respective levels. There was in all the sixteen cases a close correlation in time between sudden changes in EEG and changes in the respiratory variables recorded. The findings suggest a close functional relationship between the respiratory centers of the brain stem and the reticular activating system which supposedly controls the cortical state of excitability.
Distribution and Concentration of Adrenaline and Noradrenaline in the Adrenal Medulla of the Rat Following Reserpine‐Induced by Muscular Work
Authors: Eränkö Olavi , Härkönen Matti 
Published: December 2008

AbstractEränkö O. and M. Härkönen. Distribution and concentration of adrenaline and noradrenaline in the adrenal medulla of the rat following depletion induced by muscular work.The rats were allowed to run for 16 hours, to rest for 12 hours and to run again for 10 hours. They were killed immediately, 3, 6, 12 or 19 days thereafter. Concentrations of adrenaline and noradrenaline in the adrenal medulla were measured chemically. The intensities of the chromaffin reaction, the iodate reaction and formalin‐induced fluorescence in adrenal sections were quantitated by microphotometry. Running caused an almost complete loss of both catecholamines from the adrenal medulla and the histochemical reactions turned almost negative. The catecholamine concentrations and the histochemical reactions returned to normal in 6 days. During the recovery phase the behaviour of the noradrenaline‐storing medullary cells differed histochemically from that of the adrenaline‐storing cells.
The Effect of Juvenile Hormone on the Respiratory Metabolism of Silkworm Pupae, as Recorded with a New Semi‐Micro Device
Authors: Steen Johan B. 
Published: December 2008

AbstractSteen J. B. The effect of juvenile hormone on the respiratory metabolism of silkworm pupae, as recorded with a new semi‐micro device.The respiration of Polyphemus pupae during normal pupal‐adult development has been compared to that during abnormal development as induced by juvenile hormone. Respiration was measured as oxygen‐uptake with a new semi‐micro recording spirometer. Striking differences were found and it is suggested that the respiratory response may be used as a sensitive assay for the juvenile hormone.
The Effects of Moderate Sleep Deprivation on the Habituation of Autonomic Response Elements
Authors: Scholander T. 
Published: December 2008

AbstractScnolander T. The effects of moderate sleep deprivation on the habituation of autonomic response elements.The phasic responses and the prestimulus values of the electrodermal activity, the pupillary size and the pulse rate, as well as the prestimulus respiration rate were recorded during monotonously repeated auditory stimulation. Intra‐individual comparisons were made between the results obtained after one night of wakefulness and after normal sleep. Among the recorded variables only two, viz. the response amplitudes (i.e. maximal post‐stimulus changes) of the electrodermal activity and the pupil were influenced in a statistically significant way by the sleep deprivation. The habituation of the response amplitude of the electrodermal activity was delayed and the mean level of the pupillary response amplitude was increased. It was assumed that these effects were due to a conflict between a wish to stay awake and the successively increasing sleepiness induced by the sleep deprivation and the monotony of the experimental situation.
Improved Technique for the Fluorimetric Estimation of Catecholamines
Authors: Euler U. S. von , Lishajko F. 
Published: December 2008

AbstractEuler U. S. v. and F. Lishajko. Improved technique for the fluorimetric estimation of catecholamines.By the addition of small amounts of ethylene diamine (EDA) to the alkali‐ascorbic acid mixture used in the trihydroxyindole (THI) method the discoloration of reaction mixture and instability of fluorescence can be prevented, allowing blanks to maintain their fluorescence values for several hours. The lutines obtained from adrenaline and noradrenaline standards and from alumina eluates are stable over a period of at least one hour. Optimal fluorescence values are obtained when the volume of alkali‐ascorbic‐acid ‐ EDA exceeds the volume of the sample by 1 ml. A proportional increase in fluorescence is observed with sample volumes up to 3 ml. The technique used for estimation of catecholamines in urine and organ extracts is described. The importance of the acidity for the release of catecholamines from conjugates in urine at room temperature is emphasized.
Effect of Dietary Selenium Dioxide, Cystine, Ethoxyquin and Vitamin E on Lipid Autoxidation in Chick Tissues
Authors: Bieri John G. , Dam Henrik , Prange Inge , Søndergaard Ebbe 
Published: December 2008

AbstractThe ability of dictary selenium dioxide, L‐cystine, ethoxyquin (1,2‐dihydro‐6‐ethoxy‐2,2,4‐trimethylquinoline) and dl‐α‐tocopheryl acetate to inhibit autoxidation in incubated tissue homogenates was studied using the thiobarbituric acid test. Ethoxyquin (0.1 %) was as effective a tissue antioxidant as was dl‐α‐tocopheryl acetate (0.01 %). SeO2 (0.14, 0.46 and 1.4 ppm) significantly inhibited autoxidation in the liver, kidney and heart; the effect varied with different vitamin E‐free diets. L‐cystine (0.3 %) reduced autoxidation in muscle when fed in a casein‐gelatine diet.
Influence of Local Temperature Changes in the Preoptic Area and Rostral Hypothalamus on the Regulation of Food and Water Intake
Authors: Andersson Bengt , Larsson Börje 
Published: December 2008

AbstractLocal cooling of the preoptic area and rostral hypothalamus induced eating in the fed goat. After dehydration to the state of aphagia, cooling of this area inhibited the animal's urge to drink and induced eating. Although in a normal goat feeding practically stops when the rectal temperature exceeds 40° C (Appleman and Delouche 1958), local cooling of the preoptic area and the rostral hypothalamus induced the goat to eat hay at body temperatures above 41° C. Warming the same area inhibited eating in the hungry animal and induced the goat to drink large quantities of water.After inactivation of the preoptic“heat loss centre” by proton irradiation in a goat, the animal became adipsic but continued to eat hay with a seemingly good appetite at body temperatures above 41°C. The anorexic effect of warming the preoptic area thus does not seem to be due to a direct thermal effect on the hypothalamic“appetite centre”. The results provide direct evidence in favour of Brobeck‘s (1948)“thermostatic” theory of the regulation of food intake and justify the further extension of this theory to involve also the regulation of water intake.
The Discharge in Single Touch Receptors Elicited by Defined Mechanical Stimuli
Authors: Höglund G. , Lindblom U. 
Published: December 2008

AbstractTo understand how a touch stimulus is coded in nerve impulses it is fundamental to know the significance of its wave form. This has been studied in the toad by means of a special technique for stimulation of individual touch receptors in situ with simultaneous recording of the skin displacement. Stimuli of various gradients, amplitudes and durations were applied to the skin surface over the receptor, and the impulse discharge in the afferent fibre was recorded from thin filaments of the dorsal root.The threshold amplitude was remarkably independent of the stimulus gradient. When the latter was increased gradually from the minimum effective value (critical slope) and upwards, the threshold fell sharply at first but then remained at the same level (Fig. 3 and 4).Prolongation of a threshold stimulus by adding a plateau phase to the initial moving phase did not result in a repetition of the response and did not make it possible to reduce the amplitude (Fig. 1). The repetitive response usually obtained on suprathreshold stimulation was either limited to the moving phase or had the highest impulse frequency during this phase (Fig. 2).Since the strongest excitation occurred during the moving phase of the stimuli, it was concluded that the deformation is the adequate stimulus. The deformed state is normally followed by no response at all or, in some receptors, by a rapidly adapting discharge.
A Presynaptic Effect of d‐Tubocurarine in the Neuromuscular Junction
Authors: Lilleheil Gunnar , Naess Knut 
Published: December 2008

AbstractEnd‐plate potentials (e. p. p.) of isolated phrenic nerve diaphragm preparation have been recorded at different stages during development to complete curarization and during recovery of the preparations. The first effect obtained during increasing curarization is characterized by the constancy of the e. p. p. during tetanic stimulation, i.e. by lack of Wedensky inhibition. This phenomenon, with a rapid decline of e. p. p., develops under the influence of tubocurarine and must probably be caused by this pharmacological influence. It is concluded that the mechanism behind the Wedensky inhibition must be of presynaptic origin, and probably be due to a reinforcement of the naturally occurring tendency to block of propagation of tetanic impulses in the last arborization of the motor nerve.The following topics are more comprehensively treated in the discussion: 1. The possible presynaptic effect of tubocurarine in relation to the classical theory of a pure postsynaptic one demonstrated by Dale, Feldberg and Vogt (1936) when single stimulation were used. 2. The possible course of release of acetylcholine during tetanic stimulation. 3. Possible desensitization of receptor substance to ACh during transmission of repetitive impulses. 4. Effect of other quaternary ammonium compounds on nerve fibres, especially on unmyelinated nerve endings.
Effect of Reserpine on the Release of Catecholamines from Isolated Nerve and Chromaffin Cell Granules
Authors: Euler U. S. v. , Lishajko F. 
Published: December 2008

AbstractIn a suspension of bovine splenic nerve granules, reserpine in concentrations of 10‐8‐10‐5 M strongly inhibits the spontaneous release of noradrenaline. The catecholamine releasing action of tyramine on nerve granules is unaffected by low concentrations of reserpine, but is almost completely blocked by concentrations of 10‐5 M. Reserpine is less active as inhibitor on suprarenal medullary granules from the rabbit and still less on cats' medullary granules. The spontaneous release occurs at a lower rate in rabbit's medullary granules than in those from the cat. No difference in the rate of release was found between adrenaline and noradrenaline from the cat's medullary granules. After administration of dopa 100 mg/kg i.v. in the rabbit the rate of release from the medullary granules was greatly enhanced. The possible action of reserpine as enzyme inhibitor is briefly discussed.
Taste Functions in the Carp An Electrophysiological Study on Gustatory Fibres
Authors: Konishi J. , Zotterman Y. 
Published: December 2008

AbstractThe electrical responses of the taste fibres in carp (Cyprinus carpio (L.)) were recorded during the application of various sapid substances. A comparison of the integrated electrical responses from the glossopharyngeal nerve innervating the palatal organ, the facial nerve innervating the lining of the mouth and the barbels, and the branchial nerve innervating the gill rakers showed that the palatal organ seems to be the principal taste organ of this fish. The records from the glossopharyngeal nerve revealed that this nerve contains chemoceptive fibres responding to a great variety of sapid solutions. The response to acid and to sucrose was particularly strong, while the integrated response to 0.5 M NaCl always was considerably weaker. The application of water to the palatal organ had no stimulating effect. Especially noteworthy was a generally quite strong response to the application of human saliva.A study of the records from 114 single taste fibres from the glossopharyngeal nerve revealed that the fibres could be divided into seven groups according to their response pattern. Highly specific response to NaCl was encountered in 14 fibres. Acetic acid (0.005 M) seemed to stimulate all taste fibres, except salt fibres. Specific response to weak acid was noticed in 3 fibres. The fibres which responded to human saliva were also stimulated by sucrose (except for 3 fibres). Touching the surface of the palatal organ did not stimulate any taste fibres.