bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organic acids and calcium in hyperventilation
Authors: Axelrod D. Robert 
Published: December 2017

Voluntary hyperventilation in male human subjects produced a rise in plasma citric and lactic acid concentrations and a fall in inorganic phosphorus concentration. The maximum changes occurred 12—25 min after the end of 15—20 min of hyperventilation. Arterial-venous differences indicate that peripheral tissue was the source of the increased concentration of organic acids. The results suggest that hyperventilation produces a change in intermediary metabolism and that the formation of organic acid-calcium complexes decrease the calcium activity at the cell membrane. Submitted on December 21, 1960
Excretion of nitrous oxide in anesthetized man
Authors: Frumin M. Jack , Salanitre Ernest , Rackow Herbert 
Published: December 2017

The elimination of N2O was studied in anesthetized man in order to define the excretion process. The end-tidal concentrations of N2O were determined for approximately 30 min during washout produced by breathing air at rates of alveolar ventilation producing end-tidal CO2 tensions of approximately 40 mm Hg. The average excretion curve was resolved into three exponentials and the constants determined. Submitted on February 6, 1961
Coefficients of normal blood glucose regulation
Authors: Bolie Victor W. 
Published: December 2017

A previously formulated glucose-insulin feed-back theory was simplified with appropriate assumptions for the purpose of determining which physiological sensitivity coefficients dominate the mathematical characteristics of the normal insulin and glucose tolerance curves. It was found from experimental data that these physiological coefficients approximate the well-known critical damping criteria of servomechanism theory. Correlations between theoretical and experimental results were made with some particular solutions of the necessary differential equations, obtained with the aid of an electronic analogue computer. Using a distribution volume of 17.5 liters for the 70-kg adult in three different methods of approach, it was found that the average coefficients of the insulin and glucose responses of the liver, pancreas, and peripheral tissues are approximately ⍺ = 0.780 unit/hr/unit, β = 0.208 unit/hr/g, γ = 4.34 g/hr/unit, and δ = 2.92 g/hr/g. Submitted on December 27, 1960
Relation of respiratory alkalosis to hypokalemia in anesthetized dogs during altitude stress
Authors: Gold Armand J. , Barry Jeanne Q. , Ferguson Frederick P. 
Published: December 2017

Results of this investigation confirm the hypothesis that respiratory alkalosis is directly related to hypokalemia in dogs during their exposure to moderate altitude stress. Anesthetized animals were placed in a decompression chamber and subjected to a simulated altitude of 30,000 ft for 30 min. Arterial blood samples were obtained prior to and during the decompression period. In one series of 14 experiments in which animals breathed room air, the mean plasma K+ concentration declined from 3.9 to 3.4 mEq/ liter after 30 min. Respiratory alkalosis was demonstrated by a marked rise in blood pH (from 7.37 to 7.56) and fall in pCO2 (from 40 to 23 mm Hg) which appeared after 5 min. In a second series of 15 experiments in which dogs breathed a gas mixture containing 20% CO2 (partial pressure = 45 mm Hg at 30,000 ft), 21% O2, and 59% N2, respiratory alkalosis was effectively prevented and the characteristic hypokalemia failed to occur. It appears that potassium ions leave the plasma and enter the tissues as a secondary response to alkalosis. Submitted on March 14, 1961
Mean corpuscular hemoglobin concentration in anoxic lung disease
Authors: Verel D. , Kerridge D. F. 
Published: December 2017

An analysis of patients suffering from polycythemia rubra vera, congenital heart disease, and anoxic lung disease is presented. The effect on the mean corpuscular hemoglobin concentration (MCHC) of anoxia and increased erythropoesis is compared. The results suggest that in chronic anoxic lung disease both desaturation and increased erythropoesis may play a part in lowering the MCHC. A statistically significant relation exists between the low MCHC and increased pCO2x in addition. A discriminate analysis suggests that additional factors also play a part. Submitted on December 22, 1960
Influence of catecholamines on arterial oxygen tension in the anesthetized dog
Authors: Kreuzer Ferdinand 
Published: December 2017

Catheter oxygen pressure (PO2) electrodes for continuous recording of blood oxygen tension in vivo were inserted into the aorta of dogs anesthetized with pentobarbital and ventilated with constant volume and frequency. Femoral arteries were cannulated for pressure recording and arterial sampling for arterial oxygen tension (PaO02) calibration by polarography. Epinephrine in doses between 0.002 and 133 μg/kg and norepinephrine between 1.25 and 133 μg/kg were injected intravenously. With both agents two types of PaO02 response, without change in alveolar oxygen tension (PaO02) were observed: Type I occurred with high doses and consisted of three phases, a rise of 10—20 mm Hg, then a decrease of up to 100 mm Hg, and eventually an increase of 15–30 mm Hg. Type II was found with doses below 5 μg/kg and showed only a PaO02 increase of 10—70 mm Hg. Doses below 0.05 μg/kg were without effect. The reactions were most pronounced with breathing of 100% oxygen. This suggests an influence of the agents on true venous admixture. The effects might be due to a differential action on pulmonary and systemic (bronchial) circulation, perhaps combined with differences of action on the two sides of the heart and blood shifts. Note: With the Assistance of J. S. Picken Submitted on September 26, 1960
Pulmonary extravascular water volumes from transit time and slope data
Authors: Chinard Francis P. , Enns Theodore , Nolan Mary F. 
Published: December 2017

In single injection indicator-dilution experiments in the heart-lung system of anesthetized dogs, labeled water has a significantly greater distribution volume than simultaneously injected Na22 or T-1824, which have nearly identical concentration-time curves. Values for needle-to-needle vascular and aqueous compartments are calculated from the blood flow and the appropriate mean transit times. Values for the extravascular pulmonary water compartment, obtained by difference, are of the order of 4.3 ml/kg body wt. Similar calculations from the slope volumes (Newman et al., Circulation 4: 735, 1951) provide values of the order of 3.0 ml/kg body wt. The approximate concordance of the two sets of values is not considered validation of the slope calculation, which remains without an anatomically defined basis. Other limitations of the experimental procedures and calculations are considered. The value of 4.3 ml/kg body wt. obtained by the transit time calculation is considered to provide an upper limit to the volume of pulmonary tissue water involved in gas exchanges. Submitted on September 12, 1961
Subcutaneous, muscle, and body temperatures in anesthetized man
Authors: Smith N. Ty 
Published: December 2017

Temperatures were recorded continually in 39 patients. Preinduction temperatures were, in decreasing order, (P < .01) 1) rectum and esophagus, 2) intercostal muscle, 3) gastrocnemius muscle and intercostal subcutaneous, 4) tibialis anticus muscle, and 5) tibialis anticus and gastrocnemius subcutaneous. During analgesia-muscle relaxant anesthesia, temperatures remained more stable than during deeper anesthesia. Both rectal and esophageal temperatures were unreliable indicators of the course of other temperatures. The trend of diaphragmatic temperatures suggests that the action of nondepolarizing neuromuscular blocking agents may be intensified following thoracic surgery and that of depolarizing agents prolonged and intensified following accidental hypothermia. During low spinal anesthesia, peripheral temperatures exceeded rectal temperatures for brief periods. Submitted on June 27, 1961
Effect of salicylates on elevation of body temperature during exercise
Authors: Downey John A. , Darling Robert C. 
Published: December 2017

An attempt was made to determine the effect of orally ingested acetylsalicylic acid (ASA) in moderate amounts for varying periods of time, on temperature response of ten healthy young men walking on a power-driven treadmill with a work load of approximately 6 mets. Three experiments were conducted, ranging from one dose of 1.8–2.4 g ASA to 3.6–4.8 g/day in divided doses for 48 hr, and the same amount in divided doses for 5–7 days, the dose in the first experiment and the last dose in those following being given 1frac12–2 hr before exercise. Rectal temperature was measured at rest, during exercise, and for 20–45 min of recovery. Blood levels of salicylate were determined, hematocrits were recorded, and total proteins were determined; each subject was weighed before and after exercise. It was found that rise in body temperature was not modified by ASA in any of the various dosages, nor was significant hemodilution of the blood caused. Suggestive, but not conclusive, evidence emerged indicating that salicylates accelerate the early stages of the fall in body temperature after exercise. Submitted on October 5, 1961
Acceleration-induced strains in the intact vertebral column
Authors: Evans F. Gaynor , Lissner H. R. , Patrick L. M. 
Published: December 2017

Results of more than 170 tests with the embalmed bodies of a 69-year-old white male and two Negro males 56 and 82 years of age which were subjected to a maximum acceleration of 20 g revealed an approximately linear relation between acceleration and strain in the sacral ala and lumbar vertebrae. This relationship was less linear for the thoracic and cervical vertebrae. The magnitude of compressive strain in the anterior aspect of the body of C3 and L3 is a function of the degree of freedom of movement of the head and thorax. The strain in C3 is progressively increased by increasing freedom of movement of the head and thorax but the opposite effect occurs in L3. The anterior aspect of the body of C3 is subjected to compressive strain in the normal position of the head but extension of the head changes the strain to tension. Seating the cadaver on a polyurethan cushion 4 in. thick increased the peak strain in the vertebral column. No vertebral fractures or dislocations demonstrable by X rays have been produced by maximum accelerations of 20 g. End-plate fractures of 28 fresh vertebrae were produced by an average load of 672 lb (435–900 lb) statically applied in a materials-testing machine. Submitted on August 11, 1961
Urinary excretion of calcium and strontium 85 in man
Authors: Samachson Joseph , Spencer-Laszlo Herta 
Published: December 2017

Urinary Sr85 and stable Ca excretions were compared in 45 patients after intravenous or oral administration of the radioisotope. Although correlations were found between Sr85 and Ca excretions, there was a wide range of Sr85 excretions at a given Ca excretion. The best correlation appeared to be between Sr85 and Ca clearances. Empirical equations and curves are given to permit an estimate of urinary Sr85 excretion from Ca excretion. The renal tubular reabsorption of Ca was greater than that of Sr85 in all patients, whether Ca excretion was low or high. Fluctuations of urinary Sr85 in a given individual were related to those of Ca to calculate reproducibility of a study. Submitted on September 5, 1961
Respiration and phosphorylation in liver and heart mitochondria from altitude-exposed rats
Authors: Strickland E. Hardin , Ackerman Eugene , Anthony Adam 
Published: December 2017

Studies were made of respiration and oxidative phosphorylation in heart and liver mitochondria isolated from adult rats continuously exposed to simulated altitudes of 17,000, 20,000, or 21,000 ft for 2–7 weeks. Hypoxia had no effect on the P:O ratios in either heart or liver mitochondria, but some other aspects of mitochondrial respiration were altered in altitude-exposed rats. Liver mitochondrial respiration of rats maintained at 21,000 ft was lower than that of controls (succinate respiration, –30%; agr-ketoglutarate, –10%; β–hydroxybutyrate, –20%). In mitochondria from the hearts of rats exposed for 6 weeks to 17,000 ft, respiratory stimulation with ADP was greater than in mitochondria from the hearts of control animals. Submitted on March 13, 1961
Effects on rats of exposure to heat and vibration
Authors: Megel H. , Wozniak H. , Sun L. , Frazier E. , Mason H. C. 
Published: December 2017

Restrained adult male rats of the Sprague-Dawley strain were exposed for a 20-min duration to sublethal intensities of heat, vibration, and to the combination of heat and vibration. The incidence of mortality resulting from simultaneous exposure to both environmental stresses was significantly greater than would be predicted if these stresses were to act independently of each other. Hematocrit, hemoglobin, and serum glutamic-oxalacetic transaminase levels were significantly elevated immediately after vibration. Heat in combination with vibration increased these values although heat stress per se caused no change from control levels. Twenty-four hours after exposure to the combination of vibration and heat, hematocrit and hemoglobin levels returned to normal but the serum glutamic-oxalacetic transaminase levels were still significantly elevated. Significant increases in heart, kidney, and adrenal weights were observed immediately after exposure to the combination of environmental stresses. Possible modes of action are discussed. Submitted on November 16, 1961
Nociceptive threshold measurements in the cat
Authors: Rice Charles E. , Kenshalo D. R. 
Published: December 2017

Five cats were trained to give a leg-lift response in order to turn off a thermal radiation source. The minimum duration of thermal radiation that would consistently evoke a leg-lift response was taken to be the noxious threshold. The mean calculated skin temperature for the five experimental cats, at threshold, was 52.6 ± 0.35 C. This is compared to a mean calculated skin temperature of 44.5 ± 0.13 C for human subjects under identical conditions of stimulation. Submitted on June 4, 1962
Reflex effects of upper airway irritation on total lung resistance and blood pressure
Authors: Nadel Jay A. , Widdicombe John G. 
Published: December 2017

Mechanical irritation of the laryngeal mucosa reflexly increased total lung resistance distal to the larynx in cats anesthetized with chloralose and urethan and in decerebrate cats. The afferent limb of the reflex is in the superior laryngeal and the efferent limb in the vagus nerves. Stimulation of the larynx also increased activity in efferent parasympathetic nerve fibers going to the trachea and bronchi. Mechanical irritation of the nasal mucosa did not change total lung resistance. Stimulation of the nares or larynx increased arterial blood pressure conspicuously in decerebrate cats but only slightly in cats anesthetized with chloralose and urethan. The efferent path of the hypertensive response is in the sympathetic nerves, the afferent path for the nasal effect is in the fifth cranial nerves, and the afferent path for the laryngeal effect is in the superior laryngeal nerves. Submitted on March 6, 1962
Relationships between stimulus and work of breathing at different lung volumes
Authors: Marshall Robert 
Published: December 2017

An electrophrenic stimulator has been used on anesthetized cats and dogs to investigate the intrathoracic pressure produced by a given stimulus at different lung volumes. With a stimulus of fixed strength the resulting intrathoracic pressure swing bears an inverse relationship to lung volume. The mechanical work done in response to a given stimulus is dependent on the viscoelastic properties of the lungs and chest wall. The muscular work resulting from a stimulus and the efficiency of the chest muscles are also dependent on the position of the diaphragm and possibly on the position of the remainder of the chest wall. Submitted on February 27, 1962
Determination of alveolar capillary temperature
Authors: Edwards A. W. T. , Velasquez T. , Farhi L. E. 
Published: December 2017

Since the alveolar temperature influences the solubility of most inert gases in pulmonary capillary blood, knowledge of the solubility in arterial blood may be used to determine the equilibration temperature, i.e., alveolar temperature. Because the partial pressure of inert gas in arterial blood cannot be deduced from the alveolar pressure, direct determination of solubility is impractical. However, if a mixture of two inert gases is used, the ratio of partial pressures in the arterial blood is equal to that in the inspired gas and the ratio of gas contents will vary with the ratio of solubility. The blood solubility ratio He/A varies by 1.34% per degree centigrade. Using an O2-He-A inspired mixture, the following points were established in five resting subjects, fully clothed. 1) The pulmonary capillary temperature (Tpc) is linearly related to the rectal temperature (Tr), with a regression line equation: Tpc = 37.5 + 2.4 (Tr – 37.1). 2) When measurements were obtained on the same subject in different days, these measurements show that variations in Tpc are in the same direction as changes in Tr, but much more pronounced. Note: (With the Technical Assistance of M. Passke) Submitted on July 24, 1962
Ventilatory effects on left atrium and pulmonary vascular resistance
Authors: Kuramoto K. , Rodbard S. 
Published: December 2017

Pulmonary vascular resistance was studied in thoracotomized dogs enclosed in a respirator. The lung was inflated by respirator pressure, the trachea being open to the atmosphere. Blood flow through the lung was held constant. “Intrapleural” and left atrial pressures fell equally during inspiration; the pulmonary arterial pressure fell to a lesser extent. Calculated resistance increased during the midinspiratory phase and became maximal at end-inspiration and early expiration. Negative-pressure lung inflation had only small effects on resistance at minimal negative respirator pressures; resistance increased markedly as “intrapleural” pressure became progressively more negative. Resistance returned to control values at each end-expiration, regardless of the previous degree of negative-pressure inflation. Resistance increased in isolated lungs under constant flow perfusion when pulmonary venous and “intrapleural” pressures oscillated together; resistance fell when pulmonary venous pressure was held constant with respect to atmospheric pressure. The results suggest that previous disagreements on pulmonary vascular resistance may have been due to failure to evaluate the effect of “intrapleural” pressure on left atrial pressure. The increased resistance during negative-pressure inflation may result from a negative transmural pressure in the collapsible vessels of the lung. Submitted on July 18, 1962
Abdominal muscle and diaphragm activities and cavity pressures in pressure breathing
Authors: Bishop Beverly 
Published: December 2017

The respiratory contribution of the diaphragm and external oblique abdominal muscle has been assessed by recording from the anesthetized cat the integrated electromyograms during continuous pressure breathing. As the intrapulmonary pressure is progressively reduced from 0 to -12 cm H2O, the diaphragm becomes increasingly active until it has no silent period during the respiratory cycle. Concomitantly, any respiratory activity in the abdominal muscle is completely silenced. A hyperactive diaphragm and relaxed abdominal wall can account for the constancy seen in the directly recorded intra-abdominal pressure even though the intrathoracic pressure falls. When the animal is subjected to pressures from 0 to +14 cm H2O, the diaphragm is initially inhibited and the abdominal muscle becomes increasingly active. In every animal, on positive pressure the abdominal muscle becomes active during expiration and in 20% of the animals it is also active during inspiration. Active expiration continues throughout the pressure breathing and is sufficient to reverse the breath by breath abdominal pressure variations. During negative pressure breathing, respiration is an inspiratory act and only the thorax is subjected to stress. During positive pressure breathing, respiration is an expiratory act and both the thorax and abdomen are subjected to the stress. Submitted on May 21, 1962 Note: (With the Technical Assistance of J. R. Blumstein and D. Pennec) Submitted on January 22, 1962
Effect of expiratory flow patterns on lung emptying
Authors: Young A. C. , Martin C. J. , Pace William R. 
Published: December 2017

Differences in expired alveolar gas concentrations with changes in expiratory flow were studied in single-breath experiments using nitrogen and carbon dioxide meters. High flow rates preferentially emptied lung areas having low ventilation-to-volume ratios and high ventilation-to-perfusion ratios, whereas low flow rates preferentially emptied areas of high ventilation-to-volume and low ventilation-to-perfusion ratios. Selective emptying of different lung areas by varying the expiratory flow pattern was not affected by age, sex, or body position. A model of the lung is proposed to explain how ventilation-to-volume ratio differences can be seen at mouth level during constant slow, varying, and constantly increasing or decreasing expiratory flow. Submitted on May 4, 1962
Electroencephalographic activity after circulatory arrest in the hypothermic dog
Authors: Gökhan Nuran , Angelakos Evangelos T. 
Published: December 2017

Determinations were made in dogs of the time lapse between occlusion of venae cavae and electrical silence in the electroencephalograph (EEG) at several hypothermic temperatures. Moderate hypothermia appeared to have a protective effect on the electrical activity of the brain after circulatory arrest. The time lapse was found to be longest near 28 C. At lower temperatures cooling had a gradually increasing direct depressant effect on brain cell activity, and the time lapse between occlusion and EEG silence was shortened. However, near 22 C it was still longer than at normothermic temperatures. EEG activity virtually ceased at brain temperatures of 20–18 C. The results are interpreted on the basis of a depressant effect of hypothermia on the metabolic rate of the brain and a correlation between metabolic rate and EEG activity. Submitted on May 8, 1962