bluuebunny/crossref_metadata_2025_split huggingface dataset:
Innervation Zone and Propagation Velocity in Human Muscle.1
Authors: BUCHTHAL FRITZ , GULD CHRISTIAN , ROSENFALCK POUL 
Published: December 2008

Summary.The innervation of the brachial biceps was found to be localised to a narrow band in the proximal third of the short head and in the distal third of the long head. Counts of terminal nerve endings showed that 67 per cent of all endings were situated within 10 per cent of the muscle length.The action potential recorded with an electrode placed within the zone of innervation had an abrupt onset, and with two or more electrodes placed in the innervation zone near fibres of the same motor unit, the initial deflection of the action potential was simultaneous within 0.5 msec. This was seen up to electrode distances of 40 mm, along the longitudinal axis of the muscle, and indicates that the end plates of the same unit are scattered over this area. It excludes furthermore that propagation over the thin terminal nerve branches contributes to the action potential duration.When care was taken to place the electrodes distal to the site of innervation and an identical threshold to electrical stimulation had ensured that the electrodes led off from the same muscle fibres, the propagation velocity of the spike of the action potential released by voluntary effort varied over a narrow range. The mean value was 4.7 m/sec. with a maximal variation of 1.3 m/sec. within the same muscle (36.57° C). The small variation in velocity was unexpected in view of the threefold variation in diameter, but could be accounted for by the influence of the external resistance which was shown to be localised mainly in the interspaces between inactive fibres in situ.The propagation velocity during voluntary effort exceeded the velocity of electrically activated fibres by 0.7 m/sec.Differences in action potential duration during voluntary effort can mainly be attributed to the spatial dispersion of the site of innervation for the different fibres of the motor unit.
“In Vitro” Hemolysis of Erythrocytes from Vitamin E Deficient Rats and Chicks.
Authors: Christensen Frede , Damu Henrik , Gortner Ross A. , Søndergaard Ebbe 
Published: December 2008

Summary.When red blood cells of rats deficient in vitamin E are suspended in isotonic (0.9%) NaCl solution and allowed to stand overnight at room temperature, extensive spontaenous hemolysis occurs. This oxidative process is accelerated by incubating the suspensions at higher temperatures, hemolysis being nearly complete within one hour at 47° C.Hemolysis did not occur when purified N2 had been bubbled through the erythrocyte suspension in saline to remove free O2.Although dialuric acid increases the rate of hemolysis, the presence of this substance, hydrogen peroxide, or other added autoxidizable compound or oxidizing agent is not essential to the process.The incorporation of small amounts of methylene blue in the diet of vitamin E deficient rats affords marked but incomplete protection against in vitro hemolysis.Erythrocytes from tocopherol‐depleted chicks (on an encephalomalacia producing diet) manifesting severe deficiency symptoms are much more resistant to hemolysis than are those from rats. Spontaneous hemolysis of chick red cells in saline solution was not noted within 24 hours even when the cell suspensions were incubated at temperatures up to 47° C for 7 hours. The addition of dialuric acid caused faint to moderate hemolysis within 4 hours in about half of the birds studied.It is concluded that whereas the in vitro hemolysis of red cells may be used for assessing vitamin E deficiency in the rat, it is not a reliable criterion for determining a deficiency of this vitamin in the chick.
Growth Failure Caused by Mild Heat Treatment of the Diet
Authors: Reinius L. 
Published: December 2008

Summary.The effect of mild heat treatment on the nutritional value of a diet composed to correspond to the average composition of the diet of the Finnish people has been investigated. The test diet was dried and then kept at 140° C for 30—40 minutes. Rats were used as test animals.The heated diet caused a total cessation of the growth of the rats. The growth was restored by the addition of casein or lysin. Leucine, methionine, histidine, vitamin B12 and sucrose were without effect.
Efficiency of Pulmonary Ventilation during Rest and Light Exercise. A Study of Alveolar Nitrogen Wash‐out Curves in Normal Subjects.
Authors: Bouhuys A. , Hagstam K.‐E. , Lundin G. 
Published: December 2008

Summary.The ventilatory efficiency has been studied at rest and during exercise in 9 normal subjects. For light and moderate degrees of work the relative efficiency is the same as at rest. This conclusion is based upon determination of the pulmonary nitrogen clearance delay percentage (Fowler) and of the lung clearance index (Becklake); the latter is the more dependable of the two indices. The wash‐out time, i.e. the time it takes to wash out the pulmonary nitrogen from 80% down to 2%, decreases with increasing respiratory minute volume and increases with increasing lung volume. For gas analysis a modified nitrogen meter (Lundin and Åkesson 1954) was used.
The Inhibition of Hexokinase Reaction in the Rat Diaphragm by 2,4‐Dinitrophenol.
Authors: Jervell Kristian F. , Walaas Eva , Walaas Otto 
Published: December 2008

Summary.1. The effect of 2,4‐DNP on the glucose uptake in the isolated rat diaphragm and on the hexokinase reaction in the particulate and soluble fraction of the diaphragm has been investigated.2. 5 × 10‐5M 2,4‐DNP inhibited the glucose uptake in the diaphragm both under aerobic and anaerobic conditions. 2,4‐DNP blocked the stimulating effect of insulin on the glucose uptake in the diaphragm, while 2,4‐DNP — adrenaline gave additive inhibition.3. 10% of the hexokinase was associated with particles isolated from the diaphragm, while 85% was found in the soluble fraction. Glucose‐6‐phosphate inhibited the hexokinase, non competitive with ATP.4. 1 × 10‐4M 2,4‐DNP inhibited the hexokinase reaction in the particulate fraction. The soluble fraction was relatively resistant to 2,4‐DNP since 5 × 10‐4M gave only slight inhibition. The inhibition of the hexokinase reaction was cancelled when the ATP‐concentration in the system was increased.5. The experiments indicate that 2,4‐DNP inhibits the glucose uptake in the surviving diaphragm by stimulating the deposphorylation of ATP with subsequent reduced turn‐over velocity in the hexokinase reaction.
The Effect of Yohimbine and Adrenaline on the Oxygen Consumption
Authors: Mohme‐Lundholm Ella 
Published: December 2008

Summary.The effect of yohimbine, adrenaline, and a combination of the two on the oxygen consumption and the lactic acid content of the blood was studied in guinea‐pigs and rabbits.In guinea‐pigs, yohimbine in an intramuscular injection of 1 mg per kg increased the oxygen consumption by an average of 14.2 per cent between 20 and 115 minutes after the injection.In rabbits, yohimbine in an intravenous injection of 1 mg per kg had no demonstrable effect on the oxygen consumption.In both guinea‐pigs and rabbits, yohimbine totally inhibited the stimulating effect of adrenaline on the oxygen consumption.In the rabbit experiments the effects of yohimbine and adrenaline on the lactic acid content of the blood were also investigated. Each of those drugs produced an elevation. When yohimbine and adrenaline were administered jointly, the former totally inhibited the lactic acid forming effect of the latter.
Accelerated Rate in Isolated Auricle of Rat Treated with Triiodothyronine and its Azo Derivates
Authors: Hirvonen Leo , Lybeck Harry 
Published: December 2008

Summary.The biological action of l‐triiodothyronine, azo‐arsenophenyl‐triiodothyronine and azo‐sulfophenyl‐triiodothyronine was determined on the basis of their positively chronotropic effect on the isolated spontaneously beating rat auricle after a three days treatment of the animals with the substances in question. It is evident that triiodothyronine has an accelerating effect on the rate of beat similar to that of thyroxine. An effect of the same kind but weaker, could also be demonstrated with the azo‐compounds.
Observations on the Metabolism of Arctic Ground Squirrels (Citellus Parryi) at Different Environmental Temperatures
Authors: Erikson Harald 
Published: December 2008

Summary and Conclusions.The metabolic rate of Arctic ground squirrels was determined and found to be of the same magnitude as common in mammals.Determinations during sleep at night showed a reduction of the metabolic rate to about 50 per cent of the average daytime values.The squirrels seemed to tolerate environmental temperatures from — 30° to + 40° C well; at higher temperatures they only survived limited exposure (about 1 hour at + 50° C).The metabolic rate remained fairly constant at environmental temperatures from + 10° to + 50° C; at lower temperatures their activity and metabolic rate increased. Scholanderet al.(1950).In the fall, when the animals gained weight, high RQ's (from 1.0 to 1.4) were usually found the first hours after feeding, when the environmental temperature was above 0° C, and always when it was above + 20° C. At 0° C and lower, the RQ's were always “normal” (0.7 to 1.0). This effect of the environmental temperature on the metabolism which was found the first hours after feeding diminished rapidly after approximately 4 to 5 hours.In the following spring when the squirrels did not gain weight, changes in the environmental temperature did not affect their RQ.
The Body Temperature of Arctic Ground Squirrels (Citellus Parryi) at Varying Environmental Temperature
Authors: Erikson Harald 
Published: December 2008

Summary and Conclusions.Measurements of the body temperature of Arctic Ground Squirrels at varying environmental temperatures are described.On unrestrained animals the body temperature was found to be constant (between 36.5° and 39° C) at environmental temperatures from — 30° to — 30° C. Similar results have been obtained on other arctic mammals by Irving and Krog (1954).At + 38° C a marked increase in body temperature (to about 41° C) was found, but the animals survived. Restrained animals showed a greatly reduced tolerance to cold; the heat tolerance was slightly impaired.
Reproduction Capacity of Rats in Relation to Diet
Authors: Christensen Frede , Dam Henrik 
Published: December 2008

Summary.No improvement of reproduction capacity of female rats resulted from increase of the casein level from 20 to 40% in a vitamin E free diet with 4% lard or from adding 1.5 microgram of vitamin B12 per 100 g of diet.On corresponding diets with vitamin E (20 mg % d, 1‐α‐tocopherol acetate) the abovementioned dietary changes had no influence on the normal reproduction capacity.
Functional Organization of the Dorsal Spino‐Cerebellar Tract in the Cat
Authors: Laporte Y. , Lundberg A. 
Published: December 2008

Summary.Intra‐axonal recording in Flechsig's fasciculus was used to study the pattern of discharge in second order neurons on adequate stimulation of stretch receptors from a muscle, the group I afferents of which on electrical stimulation did excite these neurons.Of 47 such neurons examined 32 showed a discharge or an increase in frequency in a resting discharge when the tendon of the muscle was pulled. With a strong pull of the tendon some second order neurons did discharge at 70 per sec but usually the maximal frequency was much lower.In 30 neurons examined which reacted to a pull of the tendon with an increased frequency of discharge a single twitch of the muscle caused the discharge to pause. It is concluded that excitatory group I fibres have their peripheral terminals on muscle spindles.In 10 neurons passive stretching of the muscle did not give discharge or increase in the resting discharge and in 5 neurons a pull of the tendon did inhibit the resting discharge.Adequate stimulation has also been used to activate neurons which were excited on electrical stimulation of ‘skin’ nerves. Some neurons were activated by light touch, others only with application of pressure or bending of joints and a comparatively large number were caused to discharge at a high frequency by pressure of the pads.
Permeability of Human Placenta to Glucose, Fructose, and Xylose.
Authors: HOLMBERG N. G. , KAPLAN B. , KARVONEN M. J. , LIND J. , MALM. M. 
Published: December 2008

Summary.The permeability of the human placenta to glucose, fructose, and d(+)xylose was studied in situ in connection with legal abortions. The mother was given an intravenous injection of the sugar at constant speed. Blood samples were taken during the injection from the umbilical vein as exposed through vaginal hysterotomy and simultaneously from the mother. In other experiments, sugar solutions were injected into the umbilical vein, and blood samples were taken repeatedly after the injection.The results are expressed as “apparent net transfer rates” (ANTR), i. e. as the change of umbilical vein glucose, fructose, or xylose level per minute, as divided by the mean mother‐foetus gradient along which the change was occurring. The transfer of glucose and xylose proved fast in comparison to that of fructose. The ANTR values are in the same range as the corresponding figures for guinea pig or sheep placentae.The value of the method and the implications of the results are discussed1
Content and Intracellular Distribution of Adenosine Triphosphate in Cow Adrenal Medulla1
Authors: FALCK BENGT , HILLARP NILS‐AKE , HOGBERG BERTIL 
Published: December 2008

Summary.In nine experiments performed with ion exchange chromatography of the acid soluble phosphorus compounds in the cow adrenal medulla it was found that this tissue contains on the average 505 mg ATP per 100 g wet weight. There are reasons to suppose, however, that about 25 % of the ATP in the living cell have broken down before extraction could take place. The real content would thus be about 700 mg/100 g.The analyses further showed that ATP is the main phosphate ester in the medulla. AMP – if present at all – can amount to only some few per cent of the ATP quantity. The medulla may contain ADP up to 20% of the ATP amount but there are reasons to believe that the observed ADP (?) content may be only a result of ATP breakdown.As well experiments on the distribution of acid‐labile phosphates within the medullary cell as ion exchange chromatography of the phosphorus compounds in the specific granules of the medullary cell showed that ATP almost exclusively is localized to these granules containing the sympathomimetic amines. No AMP and only small amounts of ADP (?) and of inorganic P were found in granules isolated and washed in 0.3 M sucrose.The content of acid‐labile phosphorus in washed granules was on the average 74 μg/1,000 μg catechols and more than 90% of this amount can be referred to ATP. The granules can thus contain about 550 μg ATP/1,000 μg catechols (about 9% of the dry weight of the granules).The ATP in the medullary granules shows a remarkable stability. It is not released or split to any significant degree in granules suspended in 0.3 M sucrose and kept at + 4 C up to 72 hours.
A Vitamin B12‐binding Factor Formed in Cultures of Euglena gracilis var. bacillaris
Authors: KRISTENSEN H. P. ØSTERGAARD 
Published: December 2008

Summary.Supernatants from centrifuged cultures of the vitamin B12‐requiring alga, Euglena gracilis var. bacillary, contain a ther‐molabile factor, which combines with the vitamin. The complex of vitamin B12, and the “Euglena factor” thus formed cannot be taken up by the wild‐type E. coli E 35 and is non‐dialyzable through cellophane. The amount of the factor in the Euglena supernatants increases with the age of the Euglena cultures and is probably an excretion product of the Euglena cells. The factor, as regards its B12,‐binding effect, its thermo ability, and its non‐dialyzability, resembles preparations of the “intrinsic factor of Castle.
The Effect of 2,4 Dinitroplienol on ATPase Activity in the Particulate and Soluble Fraction of Rat Diaphragm
Authors: BRIGHAM ELISABETH , BRINCH‐JOHNSEN TRULS , WALAAS OTTO 
Published: December 2008

Summary.1. The effect of 2.4‐DNP on the ATPase activity in the particulate aid soluble fraction of the rat diaphragm is investigated.2. A particulate fraction isolated from the diaphragm tip centrifugation at 8.000 × g for PO inins. showed ATPase activity which was accelerated by Ca++. and Mg‐+. 5 × 10‐4 M 2.4‐DNP stimulated ATPase activit? Further. Most pronounced without the addition of Ca++ and Mg++. Without the addition of inetal salts 2.4‐DNP accelerated the ATPase activity more strongly at pH 7.0 than at pH 9.0.3. The ATPase activity in the soluble fraction from the diaphragm obtained by centrifugation at 15.000 × g for 20 mins. was high and activated by Ca++ and Mga‐+. 5 × 10‐4 M 2.4‐DNP produced a slight stimulation of ATPase activity. Purified myosin ATPase was slightly stimulated by 2.4‐DNP and p‐nitrophenol.
The Composition of Pancreatic Juice as Compared to Sweat, Parotid Saliva and Tears.
Authors: BRO‐RASMUSSEN FREDE , KILLMANN SVEN‐ÁGE , THAYSEN JØKN HESS 
Published: December 2008

Summary.The concentrations of sodium, potassium, chloride, bicarbonate. glucose, urea and the pH of pancreatic juice, obtained in response to secretion, were examined in two dogs over a 100‐fold range of variation in secretory rate. The concentrations of sodium and of potassium were 161 (± 4) and 5.3 (± 1.1) mEq per liter respectively and independent of secietory rate. The concentration of bicarbonate was independent of secretory rate at flows exceeding 0.5 ml per minute and averaged 120 mEq per liter in one of the dogs and 85 mEq per liter in the other. At secretory rates lower than 0.5 ml per minute the concentration of bicarbonate gradually dropped to values equal to or lower than plasma concentration. The concentration of chloride varied inversely with that of bicarbonate, the sum of the concentrations of the two anions amounting to 87 (± 5) per cent of the sum of the concentrations of the two cations at all secretory rates. The pH averaged 8.05 at secretory ratos exceeding 0.5 ml per minute. The secretion/plasma concentration ratio for urea was 0.9 and 0.8 in the two dogs and in dependent of secretory rate. The secretion/plasma concentration ratio for glucose was approximately 0.2 and independent of the. concentration of glucose in the plasma.The findings are compared to previous similar studies on human sweat. parotid saliva and tears. The hypothesis is forwarded that glandular secretion involves the formation of precursor solutions which are modified by the reabsorption of sodium and of water in the ducts of the sweat and parotid glands. whereas similar reabsorptive processes cannot be demonstrated in the case of the lacrymal and pancreatic glands. Moreover. glucose appears to he conserved by the sweat and parotid glands. but not by the two other glands.
Some Aspects of the Basal Tone of the Blood Vessels.
Authors: LOFVING BIRGER , MELLANDER STEFAN 
Published: December 2008

Summary.In experiments on cats the nature of the basal vascular tone that remains after sympathectomy has been analysed.The basal tone of the vessels of the skeletal muscles is quite marked while the vessels of the paw, with its abundance of arteriovenous anastomoses, become almost maximally dilated after constrietor fibre section. On the other hand, the latter type of vessels are more sensitive to known biogenic constrictor substances. No evidence of a release of vasotonic agents from the spleen could be obtained.It is therefore suggested that basal vascular tone can hardly be a consequence of circulating constrictor agents, but is probably a matter of smooth muscle automaticity, more or less pronounced in different regions depending on the degree of functional differentiation of the vessels.
Atrophy of Salivary Gland following Adrenalectomy or Hypophysectoniy and the Effect of DOCA in Cats.
Authors: KAHLSON G. , RENVALL SIV 
Published: December 2008

Summary.1. The weight of the submaxillary gland was determined in five groups of cats: 1) normal, 2) hypophysectomized, 3) adrenalectomized, 4) adrenalectomized maintained on DOCA, 5) undernourished.2. Hypophysectomized adult cats, properly fed, can be kept for several weeks without loss in body weight. Adrenalectomized adult cats, with proper feeding and saline injections, can be kept up to 16 days with a loss in body weight of only 4–10 yo.3. After hypophysectomy the submaxillary gland looses about 40 % in weight, after adrenalectomy the gland may be reduced to less than half the original size. Dehydration does not essentially contribute to this change.4. DOCA in daily doses of 0.5–5.0 mg/kg possibly has a slight effect in preventing the atrophy of the salivary gland in adrenalectomized cats.5. In undernutrition. rcsulting in 20 % loss in body weight in four weeks, the weight of the salivary gland in per cent of body weight is the same as in normal controls.Hypophysectomy and control of completeness of the operation were done by Dr. Dora Jacobsohn, whose help we gratefully acknowledge.
Release of Adenosinc Triphosphate along with Adrenaline and Noradrenaline Following Stimulation of the Adrenal Medulla.
Authors: CARLSSON ARVID , HILLARP NILS‐ÁKE 
Published: December 2008

Summary.The adrenal medullas of cats and rats were stimulatedvia the splanchnic nerves by means of injections of morphine and insulin, respectively.In both types of experiment stimulation resulted in a drop in the ATP content of the adrenal medulla, the percentage decrease being the same as for the catechol amine content.During stimulation ATP and the catechol amines are released from the adrenal medullary granules, which remain in the medullary cells, probably essentially intact.
Symmetric Hydrolysis with Intestinal Enzymes, Acid‐Neutralizing Effect and Toxicity of Isopropyl Esters of Phenylalanine Isomers.
Authors: WRETLIND ARVID 
Published: December 2008

Summary.Earlier invrstigatioris have shown that the isopropyl ester of DL‐phenylalanine is hydrolyzed asymmetrically by pancreatic enzymes. It is also known that the isopropyl esters of both D‐ and L‐phenylalanine produce growth in rats, thus implying that they must both be hydrolyzed in the organism. This is shown in the present investigation to depend on the fact that enzymes are present in the duodenal mucosa which hydrolyze the isopropyl esters of D‐, L‐, and DL‐phenplalanine equally rapidly. A closer study has been made of this enzymatic hydrolysis of the esters. It is found that the pH optimum for enzymatic hydrolysis lies at pH 8.7 to 9.2 for the L, the D and the DL ester.The temperature optimum is found to be 50°C for all three esters. With a change in the time, pH and enzyme concentration. the rate of hydrolysis by the enzymes in question undergoes similar changes in the isopropyl ester of L‐, of D‐, and of DL‐phenylalaninc.The toxicity of the isopropyl esters of phenylalanine was determined in growing rats. The LD50 was found to be 8.7 ± 0.6 ml/kg of body weight for the D ester, 16.0 ± 0.8 ml/kg for the L ester, and 13.0 ± 0.6 ml/kg for the DL ester. The cause of death was respiratory paralysis. Pathologic changes of haemorrhagic type were observed in the pyloric portion of the ventricle and in the ileum.The acid‐neutralizing ability of the ester was determined, and found to amount to 4.9 ml of 1N hydrochloric acid per ml of ester.The possibility is suggested of using such amino acid esters for neutralization of the hydrochloric acid of the stomach.