bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Reaction of Striated Mammalian Muscle to Variations of the Parameters of Electrical Stimuli Applied to Nerre and Muscle Investigated with Special Regard to Experimental Technique
Authors: GJONE EGIL 
Published: December 2008

Summary.

The reaction of striated mammalian muscles to electrical stimdation of nerve and muscle has been studied with special reference to the effect of variations in the parameters of the stimulus on the muscular response. Experiments were performed on isolated phrenic nerve diaphragm preparations and on the gastronomic and the flexor digitorum longus muscles of rabbit in situ.
2)The absolute refractory period of the flexor digitorum longus muscle following directly applied stimuli of 0.4 msec. has been determined to range from 1.3 to 1.6 msec. Prolongation of the pulse length to 2 msec. caused an increase of the absolute refractory period up to from 2.2 to 2.3 mseo.
When the interval between two successive short nerve volleys was less than the absolute refractory period of the muscle, an additional electrical and mechanical response could be set up in the muscle by the second volley.
On use of single nerve impulses shorter than the absolute refractory period of the muscle, additional electrical and mechanical responses could also be caused by the break stimuli. This effect has been shown to be a result of the reduced conductivity of the nerve fibres during the first 2 nisec. after the conditioning shock.
Application of direct electrical stimulation to fully curried muscle gave the following results:

For impulses shorter than 3 msec., single sub maximal and maximal contractions were obtained. When the maximal niveau was reached, increase of the stimulating current usually did not cause any further augmentation of the muscle response. It has been concluded that, with this form of direct stimulation, the muscle fibres respond to the stimulus in an “all‐or‐nothing” manner. It is therefore possible by this method to investigate changes of the irritability as well as the contractility of the muscle itself.
With single impulses of 3‐6 msec. duration, additional con‐tractions were elicited by the stimulus on current break.
Single impulses of even longer duration caused repet3tive firing.
Formation of Bile Acids from Cholesterol in the Rabbit: Bile Acids and Steroids 29
Authors: EKDAHL PER‐HUGO , SJÖVALL JAN 
Published: December 2008

Summary.The conversion of cholesterol into desoxycholic and cholic acids in a rabbit has been demonstrated. These acids are excreted in the bile mainly as conjugates with glycine. Fractionation of the labeled material excreted in the farces after the administration of labeled cholesterol has shown that no glycocholicorglyco‐desoxycholic acid was present. Several unidentified compounds have been formed, presumably by the action of intestinal microorganisms.
Effect of Large Amounts of‘ Plasma from Desoxygenated Blood on Erythropoiesis
Authors: HIRSJÄRVI EVA 
Published: December 2008

Summary.The effect of large amounts of plasma from blood subjected to low pressure on rabbits' peripheral blood count was studied. The injections were followed by a definite increase in the recipients' reticulocyte percentage, which was absent in a control group receiving plasma from untreated blood. In the erythrocyte count there was an initial decrease after injections of anoxic as well as untreated plasma, the normal erythrocyte level was, however, regained earlier in the anoxic group. These findings are interpreted as to confirm the theory that initially inactive blood may, in some circumstances, gain erythropoietic activity under exposure to low atmospheric pressure.
Formation of Myoglobin
Authors: BONNICHSEN R. , HEVESY G. , AKESON Á. 
Published: December 2008

Summary.Incorporation of radioiron into myoglobin of the muscles of guinea‐pigs and rats was found to be depressed to a similar extent as into hemoglobin under the effect of exposure to a dose of (500–1,400 r of) roentgen rays, in contrast to hemins, the formation of which is not in close connection with mitotic processes as that of cytochrom b or catalase.A very pronounced effect of exposure to irradiation on myoglobin formation, as indicated by incorporation of radioiron, manifests itself only after about the lapse of 1 day, which is also the case for hemoglobin formation.
The Effects of Acetyleholine, Decamethonium and Suneeinylcholine on Neuromuscular Transmission in the Rat
Authors: THESLEFF STEPHEN 
Published: December 2008

Summary.The neuromuscular block produced in the isolated nerve‐diaphragm preparation of the rat by acetylcholine, decamethonium and succinylcholine has been investigated with intracellular recording electrodes.The agents investigated are found to act on the neuromuscular junction in a qualitatively similar way.They cause a depolarization of the end‐plates from about 95 mV to 65–70 mV, and of regions distant from the end‐plate to about 70 mV. No significant repolarization of the muscle membrane occurs during the neuromuscular block.Using high concentrations of potassium, it was found that the muscle membrane had to be depolarized to 50–55 mV in order to produce a neuromuscular block in the majority of the muscle fibres.During the block of neuromuscular transmission caused by the agents investigated the muscle membrane was insensitive to the depolarizing effect of the transmitter substance.It is concluded that the neuromuscular block caused by ace‐tylcholine, decamethonium and succinylcholine is not due to a depolarization of the muscle membrane, and that the block is presumably caused by a decrease in the sensitivity of the end‐plate to the transmitter substance.
Oxygen and Carbon Dioxide Tension in the Umbilical Vessels of the Human Fetus in Prolonged Asphyxia.
Authors: WESTIN. BJÖRN 
Published: December 2008

Summary.In ten human fetuses ranging in length from 15—27 cm oxygen and carbon dioxide tensions were determined according to a method described by Björk and Hilty (1954). In the umbilical vein there was a decrease of oxygen tension with increasing elapse of time after birth. The slope of p CO2 indicated an inverse ratio. In comparison with the results obtained from the umbilical vein there is a significant decrease of p O2, respectively increase of p CO2 in the umbilical arteries. The relation of body temperature, diffusion respiration of the skin, absence of lung ventilation and diminished blood volume to the results is discussed.
The Normal Variation of Human Blood Cholinesterase Activity.
Authors: AUGUSTINSSON. KLAS‐BERTIL 
Published: December 2008

Summary.A total of 381 determinations of plasma (butyryl) cholinesterase activity and 391 determinations of erythrocyte acetylcholine‐esterase activity have been carried out on whole blood samples, applied and dried on filter paper, taken from 201 healthy human individuals, 141 males and 60 females. Specific substrates were used for the two types of cholinesterases. The results are recorded in histograms of the dispersion and statistically evaluated.The plasma cholinesterase activity of males is significantly higher than that of females. There is no such difference in the erythrocyte activity.The results are compared with those reported by other authors.The variation of the blood cholinesterase activity in one adult male during a period of two years is reported as an example of individual enzyme activity variation.
Some Properties of the Exchangeable Bone Calcium.
Authors: BAUER GORAN C. H. , CARLSSON ARVID , LINDQUIST BERTIL 
Published: December 2008

Summary.In young rats the exchangeable fraction of the bone Ca was found to consist of a (probably large) number of subfractions attaining the specific activity of the serum Ca at intervals ranging between one and six or eight hours after injection of Ca45.
Note on the Effect of X‐rays and Hormones on the Resorption Rate of Injected NaH14CO3
Authors: FORSSBERG ARNE , HEVESY GEORG 
Published: December 2008

Summary.Exposure to X‐rays, administration of adrenaline or ACTH were found to influence the rate of resorption of injected labelled bicarbonate by mice as indicated by the amount of 14CO2 exhaled. When repeating the experiments half a year later 2—3 times as high X‐ray dose and a 5 times higher adrenaline dose had to be applied to obtain the same effect on 14CO2 exhalation while no change in the sensitivity to ACTH was observed.
Two Pathways from Brain Stem to Gamma Ventral Horn Cells.
Authors: GRANIT RAGNAR , HOLMGREN BJÖRN 
Published: December 2008

Summary.Spikes in single muscle spindle afferents from the dorsal roots (cat, rabbit) or individual gamma efferents from the ventral roots can be driven by shocks to the mesencephalic tegmentum or to afferent nerves (crossed as well as ipsilateral). The latent periods from the shock to the spike have been measured.The experiments revealed the presence of a fast path from the mesencephalic tegmentum to the gamma ventral horn fibres with a latent period of only 8—9 msec (about 30 cm conduction distance). This path is crossed and, at the level of L3 to L6, can be destroyed by deep incisions into the lateral column of the spinal cord (see Fig. 8).Another pathway is activated by repetitive stimulation of the mesencephalic tegmentum. Spikes cannot be driven over this route which elicits a recruiting protracted response. This path is widely distributed over the spinal cord and stands extensive crisscross sectioning of the latter. Often the whole cord has to be divided for complete removal of the recruiting type of response.It is suggested that the fast path serves spindle and motor cooperation in fast action and that the other path acts as a general ‘volume control’ of slow tonic effects.In addition measurements are reported on gamma reflex times and the time required for the gamma effect to traverse the loop formed by gamma root efferent — muscle spindle — spindle root afferent.
The Effect of Adrenaline on the Uptake of Glucose, Mannose and Fructose in the Rat Diaphragm.
Authors: WALAAS EVA 
Published: December 2008

Summary.1. The effect of adrenaline on the uptake of hexose in the isolated diaphragm, and the mechanism of the inhibition of the uptake of glucose by adrenaline have been investigated in the present work.2. The uptake of hexose in the isolated diaphragm exhibits the following sequence glucose >mannose > fructose. Adrenaline inhibits the uptake of mannose to the same degree as glucose. With high concentrations of fructose in the medium adrenaline also causes an inhibition of the uptake of fructose.3. The mechanism of the adrenaline effect is studied in experiments where the respiration is blocked by the addition of NaCN. The carbohydrate metabolism in the diaphragm then exhibits the following features.a) The uptake of glucose in control experiments is of the same magnitude as under aerobic conditions. Adrenaline inhibits the uptake of glucose on an average by 25 per cent, an effect which is approximately of the same magnitude as the adrenaline effect under aerobic conditions.b) The concentration of hexosemonophosphate is rapidly reduced to 1/10 of the value under aerobic conditions and adrenaline has no effect. This is in contrast to the situation under aerobic conditions where adrenaline effects an accumulation of hexosemonophosphate.4. Adrenaline has no definite effect on the content of inorganic P, ATP or phosphocreatine in the diaphragm.5. Adrenaline produces a slight inhibition of the hexokinase activity in homogenate and extract of the diaphragm with an average value of 10 per cent.6. The present work indicates that the inhibition of the glucose assimilation in muscle by adrenaline is not only due to an accumulation of hexosemonophosphate intracellularly, but can also be attributed to a primary effect of adrenaline on the hexokinase reaction.
The Glycogenolytic Effect of Adrenaline on the Isolated Rat Diaphragm.
Authors: WALAAS EVA 
Published: December 2008

Summary.1. The glycogenolytic effect of adrenaline on the isolated rat diaphragm is characterized by:a) The breakdown of glycogen is partial and does not exceed 25 per cent of the initial glycogen content.b) The glycogenolysis occurs rapidly and is at a maximum after 5 mins.c) The degree of glycogen breakdown is approximately the same in glucose‐free or glucose‐containing medium (140 mg per cent) while the increase in glucose concentration in the medium (500 mg per cent) partly counteracts the effect of adrenaline.d) The effect also occurs with mannose or fructose as substrate during incubation.e) The effect is at a maximum without requiring the addition of inorganic phosphate to the medium.2. The increase of the potassium concentration in the incubation medium inhibits the uptake of glucose and the glycogen synthesis in the diaphragm. The breakdown of glycogen in the diaphragm after the addition of adrenaline is not more pronounced with a high potassium concentration in the medium.3. n‐Butanol affects the inhibition of the normal glycogen synthesis, and the glycogenolytic effect of adrenaline becomes also more pronounced. After freezing and thawing of the diaphragm the ability of glycogen synthesis is abolished.4. On addition of adrenaline in vitro, a new metabolic equilibrium in the diaphragm takes place, characterized by a lower glycogen content and an increased content of hexose monophosphate. The mechanism of the adrenaline effect is discussed.
The Binding of Histamine to Phosphatides.
Authors: LINDAHL KERSTIN M. 
Published: December 2008

Summary.When an aqueous solution of histamine is treated with lecithin or cephalin in ether solution, part of the histamine disappears from the water phase but can be recovered from the ether phase. pH influences the distribution of the histamine between the ether and the water phase.When lecithin or cephalin, suspended in buffer and added to a histamine solution, are removed by centrifugation part of the histamine adheres to the solid phase. The distribution of the histamine is influenced by pH and certain salts.The experiments carried out so far do not make it possible to decide whether the phosphatide‐histamine complex is a true molecular compound or and adsorption complex.
On the Functional Organization of the two Presynaptic Systems to the Colonic Nerve Neurons of the Inferior Mesenteric Ganglion in the Cat.
Authors: OSCARSSON OLOV 
Published: December 2008

Summary.The organization of two presynaptic systems (in the inferior splanchnic nerves and in the hypogastric nerve respectively) of the colonic nerve neurons in the inferior mesenteric ganglion of the cat has been investigated. Electrophysiological experiments have demonstrated extensive convergence of the two systems on postganglionic neurons (occlusion 80—100 per cent). The great majority of the colonic nerve neurons could be discharged from either of the two presynaptic systems as measured with tae veratrine method worked out for this purpose. Faradic stimulation of either of the two presynaptic systems has given qualitatively and quantitatively similar changes in the muscular tonus and the blood flow of the colon.
Transmucosal Migration of Water, Sodium, Chloride and Hydrogen Ions in Rabbit Ureters.
Authors: GARBY LARS , ULFENDAHL HANS 
Published: December 2008

Summary.The change in composition of fluid perfused through rabbit ureters in vivo was investigated. It was shown that1. labelled water and chloride can leave the ureter through the mucosal barrier;2. during certain conditions, a net transport of sodium and chloride through the mucosa takes place, the direction being along diminishing concentration gradients;3. moderately hypo‐ and hypertonic sodium chloride solutions evoke very small volume shifts during passage;4. hydrogen ions may easily disappear during the transport along the ureter, presumably by way of transmucosal transport.
Drinking, Antidiuresis and Milk Ejection from Electrical Stimulation within the Hypothalamus of the Goat
Authors: ANDERSSON B. , McCANN S. M. 
Published: December 2008

Summary.1. In a further study of polydipsia caused by electrical stimulation within the hypothalamus of the goat, drinking could be obtained at 33 points of stimulation in 9 animals. The localization of these points is given.2. In the anterior part of the “drinking area”, drinking evoked by stimulation was combined with antidiuresis and milk ejection (7 points of stimulation).3. Stimulation in or adjacent to the paraventricular ur supraoptic nuclei or in the supraoptico‐hypophyseal tract was followed by inhibition of water diuresis and milk ejection. No drinking was seen during these stimulations.4. Notable side effects seen during the stimulations were: temporary increase of diuresis (in the posterior part of the “drinking area”), licking, panting (in a small region in the anterior and dorsal hypothalamus) and a strange behavioral pattern, which normally may be related to a “sexual” smell in the goat.
The Effect of Hypothalamic Lesions on the Water Intake of the Dog.
Authors: Och B. Andersson , McCann S. M. 
Published: December 2008

Summary.Hypothalamic lesions which caused hypodipsia or adipsia lasting up to 14 days after the operation were made in dogs. The animals developed marked dehydration as a consequence of the impaired water intake. In contrast to the absence of “thirst”, the dogs ate and drank milk and broth readily. No correlation was found between the absence of drinking and the presence of diabetes insipidus. The degree of hypodipsia was roughly proportional to the extent of the destruction of the same area, which on electrical stimulation evokes drinking in the goat.
Contribution of the Sarcolemma to the Force Exerted by Resting Muscle of Insects
Authors: Buchthal Fritz , Weis‐Fogh Torkel 
Published: December 2008

Conclusions and Summary.1. Many insect muscles are composed of parallel, non‐tapering fibres with little connective or tendinous tissue to influence the forces measured during rest and activity. This applies to the three muscles used here: (a) the dorsal longitudinal depressor of the hindwings of the desert locust (Schistocerca gregaria Forskål); (b) the dorsal longitudinal abdominal muscle of the same insect; and (c) the dorsal longitudinal wing depressor of the water beetle Hydrophilus piceus L. (=Hydrous p.). The relevant morphological data are given in Table I and figures 3 to 6.2. Both types of flight muscles are much less extensible (passive stretch) than other striated muscles but, in locusts, the static modulus of longitudinal elasticity is of the same order of magnitude (about 8 kg. cm‐2) as in the abdominal muscle and in frog muscle.3. The sarcolemma is present as a tough membrane in locust muscle; slight squeezing of the stretched fibres produces empty sarcolemma tubes. In the flight muscle of Hydrophilus the sarcolemma, if present, has no mechanical strength compared with that of the fibrils.4. In contrast to frog muscle, the breaking force of the empty sarcolemma tube is several times less than that of the intact locust fibre. In spite of its reduced sarcolemma, Hydrophilus flight muscle exerts a considerable resistance to passive stretch. In insect muscle, therefore, the content of the fibres is responsible for the major part of the resistance to passive stretch.5. The resistance to stretch must either be due to passive‐elastic elements inside the fibre and parallel to the non‐elastic contractile elements, or the contractile system must be elastic even in the non‐active state.
The Alkaline Taste
Authors: Liljestrand G. , Zotterman Y. 
Published: December 2008

Summary.The application of alkaline solutions to the tongue of the cats is followed by a continuous outburst of impulses in the chorda tympani nerve. The alkaline taste is the result of a general stimulation of several kinds of taste fibre endings. Experiments on few fibre preparations have shown that “water fibres”, “salt fibres” and to some extent also “quinine fibres” are stimulated by alkali.
Survival and Function of Auto‐ and Homografts of Adenohypophysial Tissue in the Toad, Bufo Bufo (L)
Authors: Jacobsohn Dora , Jørgensen C. Barker 
Published: December 2008

Summary.In the toad, Bufo bufo (L), the survival and function of auto‐ and homografts of the pars distalis of the pituitary gland placed under the median eminence or under the recessus opticus of the brain were studied. The toads were supplied with the grafts after removal of the pars distalis or after hypophysectomy.All autografts were well vascularized and surviving. However, only the autografts under the median eminence receiving a vascular supply from the hypophysio‐portal system appeared normal and exerted functional activities, as judged from the condition of the skin and the length of survival of the recipient.The survival of homografts was limited. Such grafts placed under the median eminence were, however, functional during periods of up to 16 weeks. Homografts placed under the recessus opticus failed to exert the activities studied in the present work. The recipients of homografts at this site did not survive appreciably longer than toads with the pars distalis removed, and their skin showed abnormal keratinization.The observations support the assumption that in amphibians the functional significance of the hypophysio‐portal system is the same as in mammals. The importance of immunological reactions for the function of homografts of this endocrine gland is discussed.Our thanks are due to Mrs. Gunhild Nilsson for her skilled help with the histological work and to Miss Gunnel Christiansson for valuable technical assistance.This work has been supported by a grant from the Rockefeller Foundation.
Tubular Excretion of Histamine in the Hen
Authors: Lindahl Kerstin M. , Sperber Ivar 
Published: December 2008

Summary.The renal tubular excretion of injected histamine has been investigated according to a method which takes advantage of the renal portal circulation in the bird. It was found that in the hen histamine is effectively excreted by the tubules to an extent comparable with the secretion of phenol red.
On the Permeability of Guinea Pig Placenta for Thyroxine
Authors: Hirvonen Leo , Lybeck Harry 
Published: December 2008

Summary.The permeability of the guinea pig placenta to I131‐labeled thyroxine and inorganic I131 has been studied. The pertinent foetal and maternal samples were taken 3 to 4 ½ hr. after the administration of the radioactive compounds in question. The result goes to prove that thyroxine does not permeate the placenta in the first hours after its administration. Under similar test conditions more radioactivity was observed in the foetuses than in the mother animal after injection of inorganic I131.
Mechanogram Observations on the Isolated Auricle of Hypothyroid Rat
Authors: Hirvonen Leo , Lybeck Harry 
Published: December 2008

Summary.The mechanogram of isolated spontaneously beating auricle of hypothyroid (treated with I131), normal and thyroxinized rats was recorded at 4° C intervals over a temperature range of 25° to 41° C.The rate of beat in various preparations showed no qualitative differences as a function of temperature.The ability of heart muscle to increase the contraction force with falling temperature seems to presuppose the presence of thyroid action. Therefore the mechanical output of hypothyroid auricles was powerfully depressed by lowering the temperature.The weaker the thyroid activity, the longer the duration of the contraction period at a certain temperature. As a function of rate, the duration of contraction was independent of thyroid action.