bluuebunny/crossref_metadata_2025_split huggingface dataset:
Motor Hyperactivity Resulting in Diameter Decrease of Peripheral Nerves1
Authors: ANDERSSON YVONNE , EDSTRÖM JAN‐ERIK 
Published: December 2008

Summary.Two groups of guinea‐pigs were subjected to intense motor training. Fibre spectra of one unimodal and one bimodal nerve were recorded after training periods of 11 and 29 days, respectively.The data recorded show that a significant decrease in fibre diameter can be produced by hyperactivity.The mechanisms underlying the present findings are discussed. It is suggested that the consumption of substances in the processes may be so great on intense activity that it cannot be completely compensated by synthesis, thus resulting in a decrease in fibre diameter.
Potentiation by Histaminase Inhibitors of the Effects of Histamine on the Rectal Temperature in the Unanaesthetized Guinea‐Pig
Authors: WESTLING H. 
Published: December 2008

Summary.

The effects of subcutaneous injections of histamine on the rectal temperature of guinea‐pigs were potentiated by amino‐guanidine and 2‐methyl‐4‐amino‐5‐methylaminopyrimidine, two histaminase inhibitors.
The histaminase inhibitors did not increase the response of the rectal temperature to two “histamine analogues”, which have pharmacological effects resembling those of histamine. The “histamine analogues” used are resistant to histaminase in vitro.

I am grateful to dr. H. O. Schild for advice on the statistical treatment of the data. The technical assistance given by Miss M.‐B. Johansson was highly appreciated.This investigation was aided by a grant from the Medical Faculty, University of Lund.
Electrical Potential Gradients Through Frog Skin
Authors: ENGBÆK LISE , HOSHIKO T. 
Published: December 2008

Summary.The electrical potential gradients through the frog skin bathed in sulphate Ringer's were studied with microelectrodes inserted through the skin from its outer surface.The total skin potentials ranged between 73 and 145 mV, the inside positive with reference to ground. In most instances the total skin potential was reached in two, rarely three, distinct potential jumps. Comparison with measurements of the frog skin thickness indicated that the site of the first jump is in the epidermis while the second potential jump may correspond to the junction between epidermis and corium.
Anionic Dependence of Secretion and Secretory Potentials in the Perfused Sublingual Gland.
Authors: LUNDBERG ANDERS 
Published: December 2008

Summary.The sublingual gland of the cat has been found to give normal amounts of saliva in response to acetylcholine or stimulation of the chorda when perfused at 20° C with a saline containing physiological amounts of sodium and potassium and chloride and with chloride as the only anion. On intracellular recording normal secretory potentials are found over the outer membrane with activation.After replacement of chloride by nitrate in the perfusion fluid the amount of saliva in response to acetylcholine drops to 10–25 per cent of normal and the secretory potential over the outer gland cell membrane is greatly reduced. On readmission of chloride, secretion and the secretory potentials recover promptly. With partial substitution of chloride by nitrate, secretion is about 50 per cent at 10 per cent chloride and virtually normal at 50 per cent chloride.It is concluded i) that the decrease of secretion and secretory potential in the nitrate‐perfused gland is due to the lack of chloride ion in the external medium of the cells; ii) that normal secretion of salt and water is largely caused by an active transport of chloride over the outer gland cell membrane.Of other anions tested with regard to their capacity to maintain secretion bromide was found to substitute fully for chloride and iodide and thiocyanate in about the same degree as nitrate. The possibility is discussed that the activated outer membrane has a limited ability for transport of these latter ions.On perfusion with potassium‐free saline, secretion is greatly reduced. This finding is discussed in the light of the fact that in other tissues the transport of sodium and potassium is linked.
Heat Regulation and Metabolism in some Tropical Mammals and Birds.
Authors: ENGER PER STOCKFLETH 
Published: December 2008

Summary.Five species of tropical mammals and three species of high soaring birds in Panama have been subjected to various air temperatures and their heat production was determined by the carbon dioxide production. The mouse and the squirrel were good thermoregulators with a critical temperature of about 27° C, whereas the opossum, armadillo and three‐toed sloth were bad regulators. The birds have relatively low critical temperatures, about 24° (vultures) and 20° C (frigate‐bird), which may reflect their habit of soaring in cool air at high altitudes. At sub‐critical temperatures the metabolism in both mammals and birds increased with decreasing temperatures, more or less closely approaching Newton's law of cooling.The resting metabolic rates in mouse, squirrel and opossum were in accordance with the standard mouse to elephant curve. Mammals of the suborder Xenarthra (anteater, sloth, armadillo) and the three bird species had a relatively low metabolic rate.
Convergence of Tactile, Thermal, and Gustatory Impulses on Single Cortical Cells.
Authors: LANDGKREN SVEN 
Published: December 2008

Summary.Using the extracellular microelectrode technique 325 cortical cells in the tongue projection area were studied and tested by the application of mechanical, thermal, gustatory or electrical stimuli to the tongue. Out of this group of tested cells 101 cells responded to tongue stimulation. The majority of these responding cells were discharged by one type of stimulus only, but 27 cells were activated by fibres subserving different sensory modalities. The usually observed combinations of effective stimuli were cooling and touch or cooling and “stretch”, but cortical cells responding to taste and touch or taste and “stretch” were also found. In some cells even more complicated combinations of effective stimuli were observed.All cortical cells of the type responding to more than one modality were discharged via rapidly conducting afferent paths from touch or stretch receptors in the tongue. Thermal and gustatory stimuli on the other hand, activated these same cells more efficiently but with a longer latency (100–500 msec.) than did mechanical stimulation.It was concluded that the observed convergence of tactile, thermal and gustatory impulses occurred in the central nervous system.
On the Extent of Hydrolysis of Triglyceride Ester Bonds in the Lumen of Human Small Intestine during Digestion.
Authors: BORGSTRÖM BENGT , TRYDING NILS , WESTÖÖ GUNNEL 
Published: December 2008

Summary.Glycerides containing a fraction of a percentage of 2,2‐dimethyl[1‐14C] long‐chain fatty acids, the ester bonds of which are resistent to the action of pancreatic lipase, have been fed to human subjects.From the concentration of the labelled acid in the neutral fat of the intestinal contents it is possible to calculate the real extent of hydrolysis of the glyceride esters fed if it is assumed that the different glycerides are absorbed at the same rate.The results show that as a mean around sixty per cent of fed glyceride ester bonds are split in the lumen of the small intestine before absorption. About forty per cent of the fed triglycerides are completely hydrolyzed to glycerol and fatty acids, the remaining sixty per cent are partly hydrolyzed to an extent of around forty per cent, giving rise to a mixture of tri‐, di‐ and monoglycerides and free fatty acids.It is, therefore, clear that fatty acids fed to human subjects in the form of triglycerides are absorbed from the small intestine to a greater extent as free fatty acids than as glycerides.We are indebted to Prof. S. Bergström for placing the 13C‐labelled glycerides at our disposal.The technical assistance of Mrs. M. B. Nilsvik and Miss K. Sjöström is gratefully acknowledged. The investigation has been supported by grants from Statens Medicinska Forsk‐ningsråd, from Knut och Alice Wallenbergs Stiftelse, from the Medical Faculty of the University of Lund and from Statens naturvetenskapliga forskningsråd.
A Modification of the Thiocholine Method for the Determination of Cholinesterase. II. Histochemical Application.
Authors: HOLMSTEDT BO 
Published: December 2008

Summary.Based upon the biochemical controls of the thiocholine method (Holmstedt1957) the various steps of the histochemical procedure have been investigated. The inhibitors Mipafox and BW 284c51 and the substrates acetylthiocholine and butyrylthiocholine were combined as shown in Table 3 with the object of producing a reliable method of separating the two types of cholin‐esterase. Sufficient controls are included in the table to allow a distinct separation of the two types of cholinesterase.The technique of the modified thiocholine method is given in detail. The following modifications have been made.1. Inclusion of new inhibitors as above. (Mipafox and BW 284c51.)2. No presaturation with copper thiocholine.3. No development with ammonium sulphide.With the modified method, stellate ganglion, striated muscle and stomach wall have been stained in order to produce confirmation of the biochemical controls, not with the purpose of studying the morphology in detail. Comparison of sympathetic ganglia and motor end‐plates shows that the ganglion cells contain only acetylcholinesterase but that the motor end‐plates also contain a considerable amount of butyrylcholinesterase.The reasons for the alterations of the original thiocholine method are discussed. The exclusion of the presaturation with copper thiocholine produces no effect on the staining of tissue sections. The exclusion of development with ammonium sulphide diminishes diffusion artefacts to a considerable degree. Only fresh frozen sections can be used at present, if the purpose is to distinguish between the two types of cholinesterase.
Food Preferences in Obesity Caused by Goldthioglucose.
Authors: LARSSON S. 
Published: December 2008

Summary.

The preference for different diets has been studied in adult mice, both normal and those made obese by a single injection of goldthioglucose.
The normal mice did not show any changes in weight when transferred from standard to free selection diets. On free selection the caloric intake of fat and carbohydrate was about equal.
The obese mice showed marked variations in weight gain and food preferences. While gaining weight no carbohydrate was eaten in most cases.
In some cases obesity did not develop on the standard diet but only on the free selection diet.
Effect of Anastomosis Between the Hypoglossal and Chord a‐Lingual Nerves on the Supersensitivity of the Denervated Submaxillary Gland.
Authors: EMMELTN N. , MUREN A. , STROMBLAD R. 
Published: December 2008

Summary.The central stump of the hypoglossal nerve was connected to the peripheral stump of the chorda‐lingual nerve in cats, and the effect of this operation on the sensitivity of the submaxillary gland towards adrenaline was studied.The supersensitivity caused by the denervation of the gland was in these cases not found to remain on its high level but started to decrease after five to six weeks. When the hypoglossal nerve was stimulated electrically later on in an acute experiment the effects typical of stimulation of the chorda tympani ensued: secretion from the submaxillary and sublingual glands, which was abolished by atropine; and a vasodilatation in the submaxillary gland, which persisted after injection of atropine. Hexamethonium was remarkably efficient in abolishing these effects of hypoglossal stimulation.It is concluded that the fall in sensitivity was due to reinnervation of the gland from the hypoglossal nerve, indicating that the restraining influence on the sensitivity, which seems to be a function of the normal efferent nerve, is not specific to this nerve but can be exerted by other nerve fibres as well. In this particular case the effect of the parasympathetic secretory fibres was taken over by somatomotor fibres meant for the tongue.
Effect of Anastomosis Between the Hypoglossal find Sympathetic Nerves on the Supersensitivity of the Denervated Submaxillary Gland.
Authors: EMMELIN N. , MUREN A. , STROMBLAD R. 
Published: December 2008

Summary.Cross nerve anastomosis was performed between the proximal end of the hypoglossal nerve and the distal end of the cervical sympathetic trunk in cats. At the same time the chorda‐lingual nerve was cut. In some of the cats the supersensitivity of the submaxillary gland towards adrenaline, which follows this latter operation, was not maintained. The sensitivity started to decrease and at about the same time signs of reinnervation of the pupillary dilator and nictitating membrane from the hypoglossal nerve appeared. In acute experiments stimulation of the hypoglossus was then found to cause effects, characteristic of stimulation of the sympathetic trunk: secretion from the submaxillary gland (and sometimes from the sublingual and parotid glands as well); these responses were abolished by dihydroergotamine but not by atropine; vasoconstriction occurred in the gland; the pupil dilated and the nictitating membrane was withdrawn.It is inferred that the hypoglossal nerve had reinnervated the superior cervical ganglion, and that impulses from the nuclei of the XIIth cranial nerve had reached the salivary gland cells via the hypoglossal and postganglionic sympathetic fibres; and that such impulses had lowered the high level of sensitivity created by section of the chorda. The observations seem to lend further support to the opinion that the gland cells innervated by sympathetic fibres have a parasympathetic nerve supply as well.
Chromatographic Separation of Five Vitamin A1 Isomers from the Eyes of Deep‐Water Prawns (Pandalus Borealis).
Authors: BARNHOLDT B. , HJARDE WILLY 
Published: December 2008

Summary.In fractional chromatography of the unsaponifiable fraction from the eyes of deep water prawns the vitamin A1 present was found to separate into five components: a, b, c, d, and e. In two instances the relative proportions of the different isomers present, expressed by E325 measured on the collected fractions were found by chromatography to be as follows:1. a:b:c:e = 0.8:52:9:38 (d was incompletely separated from c and e, the quantity of d may be estimated to be about 0.5—1 %).2. a:b:c:d:e = 1.5:49:17:1.5:31.The results obtained suggest that substances a, b, c, and e are identical with 11.13‐di‐cis, 11‐mono‐cis, 13‐mono‐cis and all‐trans vitamin A1. respectively, while the small quantities of substance d available have rendered the identification of this substance less certain. The possibility that substance d is 9,13‐di‐cis vitamin A1 is discussed. In a preparation marketed by Messrs. Hoffmann‐La Roche & Co., Basle, under the name of “Vitamin A, Feed Grade”, the presence has been ascertained of an isomer the properties of which agree with those of substance a and 11,13‐di‐cis vitamin A1.The substances obtained were subjected to a number of identification tests: isomerization with iodine as catalyst, formation of anhydro vitamin by means of hydrogen chloride, determination of E620.,mμ Carr‐Price/En. v. max. and the maleic anhydride reaction. The spectrophotometry properties of the substances have also been examined for the purpose of establishing their identity.
Ventilatory Studies of the Lungs During Continuous Pressure Breathing.
Authors: HARBOE M. , LORENTZEN F. VOGT 
Published: December 2008

Summary.The nitrogen clearance of the lungs during oxygen breathing has been investigated by means of the nitrogen meter during continuous pressure breathing, compared with normal conditions.In all, 135 experiments have been made on 5 healthy subjects. The degree of uneven ventilation, nitrogen washout time, nitrogen washout volume and lung clearance index have been investigated.Increasing tidal volumes gave more even ventilation on some subjects but no change on others.Nitrogen clearance pattern remains stable with CPB and normal respiration.The changes in ventilation‐perfusion relationship when switching to CPB can probably — when the ventilation does not undergo any important change — be attributed to change in blood perfusion of the lungs during CPB.
Cold Defense Reactions Elicited by Electrical Stimulation within the Septal Area of the Brain in Goats.
Authors: ANDERSSON B. 
Published: December 2008

Summary.Electrical stimulations in, or in the vicinity of the septum pellucidum of unanaesthetized goats were observed to produce shivering, peripheral vasoconstriction, sometimes piloerection and in animals exposed to heat an inhibition of polypneic panting.Prolonged stimulation in room temperature caused a rise in rectal temperature of up to 0.5° C, at which stage shivering was no longer seen as result of stimulation.A lowering of the body temperature of the animals, or the exposure to cold (4° C) facilitated the shivering response.
On the Contraction of Glycerol‐extracted Muscle Fibre Bundles under Highly Isometric Conditions.
Authors: EDMAN K. A. PAUL 
Published: December 2008

Summary.A new technique for strictly isometric recording of glycerol‐extracted muscle fibre bundles is described. The apparatus works on the principle of a torsion balance.By comparing contractions of fibre bundles of different thickness from rabbit psoas conclusions can be drawn about the diffusion depth for ATP into the bundle. ATP in a concentration of 2.3 × 10‐4 M penetrates about 40 μ into a fibre bundle, probably via the endomysium, the diffusion into a single fibre amounting to only about 1 μ.The final isometric tension is proportional to the circumference of the fibre bundle, not to the cross section area.The magnitude of the final isometric tension and the rate of the isometric contraction have been studied as functions of the ATP concentration.The latency between the moment of immersion of the fibre bundle into the ATP solution and the start of the contraction is compatible with the assumption of an unstirred fluid layer of 30–45 μ around the fibre bundle.Possible factors influencing the course of isometric contraction of glycerol‐extracted muscle fibre bundles are discussed.
The Effect of Iproniazid on the Blood Pressure Responses in Dogs to Histamine Injected into the Renal Artery.
Authors: LINDELL SVEN‐ERIC 
Published: December 2008

Summary.1. Iproniazid potentiated the depressor responses in dogs to histamine injected into the renal artery.2. Some evidence was obtained that this potentiation was due to an inhibition of the histaminase in the kidney rather than to any interference with the action of a “histamine metabolizing enzyme II”.
Myocardial Oxygen Consumption and Coronary Blood Flow during Potassium‐Induced Cardiac Arrest and during Ventricular Fibrillation1
Authors: BERGLUND E. , MONROE R. G. , SCHREINER G. L. 
Published: December 2008

Summary.During perfusion of the left coronary artery from a donor dog's carotid artery, cardiac arrest and ventricular fibrillation were induced. Myocardial oxygen consumption, obtained as the product of coronary flow and coronary a‐v oxygen difference, was reduced during arrest to values below 3.5 ml/minute in 5 of the 6 dogs studied. During fibrillation the oxygen consumption was 4—9 times as high as during arrest. The importance of these findings for cardiac surgery is emphasized. The role of myocardial oxygen consumption in determining coronary flow is discussed.
On the Biochemistry and Pharmacology of Sodium Monothiophosphate.
Authors: CLEMEDSON CARL‐JOHAN , FREDRIKSSON TORSTEN , SÖRBO BO 
Published: December 2008

Summary.1. Monothiophosphate is oxidized to thiosulphate in the presence of liver tissue. The mechanism of this reaction has been elucidated.2. Thiophosphate can replace phosphate in the triose phosphate dehydrogenase reaction. However, an unstable intermediate is formed.3. The LD50‐dose of the compound is 950 mg per kg body weight as determined by intraperitoneal injection in unanaesthetized mice.4. Intravenous injection in the anaesthetized cat resulted in depression of respiration and blood pressure. No cumulative effects could be demonstrated. The neuromuscular transmission was unaffected.5. The pharmacological effects of thiophosphate has been compared with those of hydrogen sulfide and found to be different.
Oxygen Dissociation Curves in Fish Blood1
Authors: SCHOLANDER P. F. 
Published: December 2008

Summary.The oxygen dissociation curve of the common silver hake (Merluccius bilineatus) is described at pH 5.9—7.7 and pO2 0.2—140 atmospheres. At pH 7 the curve has a conspicuous plateau before it reaches full saturation at about 100 atmospheres. It is pointed out that high pressure curves from fish in general cannot readily be described or interpreted in terms of current theories evolved for mammalian blood.
The Effect of Tetraethylammoninum (TEA) and Temperature on the Neuromuscular Block Produced by Magnesium
Authors: STOVNER JACOB 
Published: December 2008

Summary. An investigation of the effect of temperature on the neuromuscular block caused by magnesium in the isolated phrenic nerve diaphragm preparation from the rat has been carried out. The effect of tetraethylammonium (TEA) on the neuromuscular depression produced by magnesium has been investigated in the rat diaphragm preparation as well as in nerve muscle preparationsin situin rabbits and cats. A concentration of 6 mM magnesium in the bath just produced complete neuromuscular block of the responses to single nerve shocks at 37°C. At 22° C 10 mM magnesium was needed. In the presence of a neuromuscular block due to magnesium at 37° C, lowering the temperature to 22° C restored transmission. TEA in a concentration of 1 mM in the bath partly restored neuromuscular transmission depressed by magnesium. The β‐hydroxy‐derivative of TEA and choline only increased the magnesium block. In the rabbit and cat TEA in a dose of 4 to 7 mg per kg body weight injected intravenously restored neuromuscular transmission strongly depressed by continuous infusion of magnesium. In spite of continuous magnesium infusion, the restoration of muscle contractions obtained with the single dose of TEA was far more sustained than the blood pressure fall caused by TEA. The sensitivity of the motor end plate to externally applied acetylcholine was not increased after TEA had restored transmission in the magnesium‐blocked rat diaphragm. The end plate potential obtained under a magnesium block was increased in amplitude without significant change in time course, when TEA was added.It is concluded that TEA like calcium antagonizes the neuromuscular block caused by magnesium by effecting an increased output of acetylcholine from the presynaptic nerve terminals.
Column Chromatography of Histaminase
Authors: SWEDIN B. 
Published: December 2008

In recent years the metabolism of histamine has been studied with isotope techniques by Schayerand co‐workers (1956) who made several interesting discoveries. They found for instance that histamine is eliminated from the organism by a united action of at least three different enzyme systems, one of which is the classical histaminase. For further studies of the problem it is most important to get the enzymes as pure as possible.I should like to give a report on an improved preparation method of histaminase. The use of a chromatographic step in the method gave a good yield with a high purification.