bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pulmonary function in different animals
Authors: Drorbaugh James E. 
Published: December 2017

Relaxation pressure-volume curves have been determined from the lungs and thorax of mice, rats, rabbits and dogs. From these data figures are obtained for body weights, vital capacity and compliance. These are compared with similar data for man and calculated values for tidal volumes and frequency of breathing obtained from the literature. Calculations were made of the elastic work of breathing per breath and per minute. All values were plotted on double log paper against body weight so that they could be expressed as proportional to some power of body weight. It was found that compliance, tidal volume, vital capacity and elastic work per breath are all nearly proportional to the first power of the body weight while the elastic work per minute, like the rate of oxygen consumption, is proportional to the 0.7 (or 0.73) power of body weight. It is concluded that lungs of large and small animals tend to have the same compliance per unit of vital capacity and require the same pressure for the intake of one tidal volume. A large lung may therefore be regarded as equivalent to many smaller lungs in parallel. Submitted on June 13, 1960
Diffusion of oxygen into a film of whole blood
Authors: Marx Thomas I. , Snyder Warren E. , St. John Andrew D. , Moeller Calvin E. 
Published: December 2017

In the study of artificial blood oxygenation, the mechanism of oxygen diffusion and absorption in a blood film is of particular interest. An equation was derived for the diffusion of oxygen into whole blood films that are thick compared to the red cell size. The equation, which was solved on an electronic analogue computer, showed that simple expressions for an advancing interface of oxygenated blood are good approximations. An equation for a blood film bounded by a semipermeable membrane was also derived. An experiment was conducted to confirm the advancing interface theory. In a second experiment, the diffusivity of oxygen in whole blood was found to be approximately 1.3 (10–5) cm2/sec. When using highly permeable membranes, such as silicone rubber, in a blood oxygenator, the relative permeabilities of a blood film and the membrane are such that in many cases the resistance of the blood film is the controlling factor. Submitted on October 5, 1959
In vivo effects of inositol phosphatide (lipositol) on serum lipids and atherosclerosis of hyperlipemic rabbits
Authors: Sachs Bernard A. , Danielson Ethel , Leiter Louis 
Published: December 2017

The profound immediate mobilization of neutral fat and cholesterol reported following soybean lipositol fraction infusion in the normal rabbit could not be demonstrated in the rabbit made hypercholesterolemic by cholesterol feeding. A delayed mobilization of neutral fat was noted 24 hours after the infusion of lipositol in saline to hyperlipemic rabbits. Contrary to results reported by others, the phosphatide infusions had no effect on the development of atherosclerosis and did not result in the resorption of already developed atherosclerotic plaques in the rabbit. Submitted on March 11, 1960
Effect of hypothyroidism on heat production and loss during acute exposure to cold
Authors: Fregly M. J. , Iampietro P. F. , Otis A. B. 
Published: December 2017

Thyroidectomy (propylthiouracil treatment) and adrenalectomy increased the rate of cooling of rats restrained and subjected to air at 5°C. At the same colonic temperature during cooling, both thyroidectomized and adrenalectomized rats maintained higher skin temperatures than control rats. Heat production (measured by oxygen consumption) was determined for thyroidectomized and control rats only. At the same colonic temperatures during cooling, thyroidectomized rats had the same heat production as controls. However, heat loss at a given colonic temperature during cooling was greater for thyroidectomized than for control rats. The inability of thyroidectomized rats to tolerate cold as well as control rats under these conditions was almost entirely due to a more rapid loss of body heat. The cause of failure of heat conservation may be related to changes in vascular reactivity induced by the hypothyroid state. Submitted on August 1, 1960
Cerebral metabolism of glucose-3-C14, pyruvate-1-C14 and lactate-1-C14 in mental disease
Authors: Sacks William 
Published: December 2017

A previous investigation indicated that less brain CO2 was derived from glucose in psychotic patients than in normal subjects and suggested pyruvate and/or lactate as the site(s) of dilution. In this report more direct determinations, using glucose-3-C14, pyruvate-1-C14, dl-lactate-1-C14, d-lactic-1-C14 and l-lactic-1-C14 acids as substrates, have corroborated the decreased cerebral oxidation of carbohydrate by chronic mental patients and indicated pyruvate as the metabolic level at which protein and/or lipid intermediate(s) caused increased dilution. After glucose-3-C14 injection 35% of brain CO2 was derived from glucose in the mental patient and 54% in the normal subject. With pyruvate-1-C14 initial values for brain C14O2 activities were lower in mental patients. Using dl-lactate-1-C14 over-all body metabolism was reduced in psychotics, whereas brain catabolism was similar to that of normal subjects. Cerebral oxidation of d-lactic-1-C14 acid was greater in mental patients although over-all body metabolism showed little difference from normal subjects. Using the l-isomer both body and brain catabolism were decreased in mental patients. Submitted on April 28, 1960
Respiratory control and work of breathing in obese subjects
Authors: Gilbert Robert , Sipple John H. , Auchincloss J. Howland 
Published: December 2017

Lung volumes, arterial blood gases, respiratory control system sensitivity, and oxygen cost of breathing were studied in obese but otherwise normal individuals and compared to similar studies in nonobese control subjects. Respiratory control system sensitivity as measured by the response to 5% carbon dioxide in air was normal in most obese subjects but reduced in certain obese individuals indistinguishable from the others on the basis of clinical evaluation or resting air studies. While breathing 5% carbon dioxide, the ventilation required to maintain any given alveolar carbon dioxide tension was directly dependent on weight. Oxygen cost of breathing in the ventilation range of 10–30 l/min. was elevated in 4 of 12 obese subjects, and in 6 of 9 obese subjects in the range of 20–40 l/min. There was no correlation between oxygen cost of breathing and respiratory control system sensitivity. Submitted on April 29, 1960
Respiratory consequences of passive body movement
Authors: Dixon M. E. , Stewart P. B. , Mills F. C. , Varvis C. J. , Bates D. V. 
Published: December 2017

The respiratory consequences of a number of passive body movements have been investigated in a group of normal subjects. It has been shown that certain types of torso movement produce hyperventilation in excess of metabolic demand, with a consequent lowering of end-tidal CO2 tension. Passive pedal motion of the legs did not produce this type of hyperventilation and concealed it if performed in conjunction with the other movements. The mechanism for the passive hyperventilation is not understood, since the respiratory rate did not appear to be rhythmically linked to the body movement, and certain maneuvers in the experiments did not affect the results. The level of hyperventilation that has been demonstrated is considered to be adequate to explain the phenomenon of hyperventilation which has been recorded in pilots flying high-velocity low-level aircraft, who may be subjected to considerable jolting while sitting in an upright position. Submitted on May 10, 1960
Lung changes and incidence of respiratory arrest in rats after aspiration of sea and fresh water
Authors: Halmagyi Denis F. J. 
Published: December 2017

Some effects of intratracheal administration of 0.1 ml/100 gm body weight of fresh and sea water were studied in intact and vagotomized rats. No local changes were seen in the lungs after fresh water inhalation. A marked increase in lung weight and intra-alveolar hemorrhages developed following the aspiration of sea water. Fatal respiratory arrest occurred in some cases of salt water and cold fresh water inhalation. Bilateral cervical vagotomy prior to the intratracheal fluid administration failed to affect the incidence of respiratory arrest. Submitted on November 30, 1959
Some cardiorespiratory parameters in anesthetized sheep
Authors: Halmagyi Denis F. J. , Colebatch H. J. H. 
Published: December 2017

Ventilated volumes, oxygen content and carbon dioxide tension in the arterial blood, cardiac output, venous admixture, systemic and pulmonary arterial pressures, and lung compliance were determined in 50 anesthetized sheep. Mean values and standard deviations are described and compared with values obtained in 11 unanesthetized sheep. Submitted on July 25, 1960
Effect of inflation of the lung on different parts of pulmonary vascular bed
Authors: Howell J. B. L. , Permutt Solbert , Proctor D. F. , Riley R. L. 
Published: December 2017

In excised lungs of dogs, the static pressure-volume characteristics of the vascular bed were determined with the vessels filled with dextran and again after replacement of the dextran with kerosene. Whereas the dextran was distributed throughout the entire vascular bed, the kerosene was distributed only in relatively large vessels due to interfacial tension. Volume-pressure curves obtained with kerosene were markedly different from those obtained with dextran. Utilizing both types of volume-pressure curves, it was possible to separate the vascular bed of the lung into two compartments that responded oppositely to inflation of the lung when vascular pressure was held constant: one compartment, consisting of relatively large vessels, always increased in volume; the other compartment, consisting of smaller vessels, always decreased in volume. Submitted on June 9, 1960
Distensibility of digital blood vessels in cold environment
Authors: Hyman Chester , Arthur James D. , Trotter Alfred Don , Humphreys Patrick C. , Winsor Travis 
Published: December 2017

To determine finger-tip vascular distensibility when all of the vessels are subjected to a uniform pressure, an appropriate plethysmograph is used to follow the increase after local venous occlusion. When the finger shows no further systematic increase in volume (volume B), an arterial occlusion is applied to the upper part of the arm. Blood will then flow from the high pressure parts of the vascular bed of the finger tip until the pressure level is related to the venous occlusion cuff pressure to give a new volume (C). Release of the venous occlusion cuff permits all of the blood vessels in the finger tip to come into equilibrium with the pressures in the vessels of the arm to give a measure of the volume (D) contained at the low pressure. The difference between volumes C and D represents the distention of the entire vascular bed of the finger tip for the pressure difference between the occlusion and the final static pressure level. When subjects are exposed to a cold environment, distensibility of the finger-tip vessels decreases, with evidence for involvement of both high- and low-pressure vessels. Submitted on September 19, 1960
Effect of altitude on endurance running of Peromyscus maniculatus
Authors: Hock Raymond J. 
Published: December 2017

One subspecies of deer mouse is distributed from the floor of Death Valley to the tops of California's highest peaks. Endurance studies were made on two populations from 4,000 and 12,470 ft, respectively, at the Owens Valley and Barcroft Laboratories of the White Mountain Research Station. Mice ran on a treadmill at a speed of 40 m/min and an inclination of 50 % (22.5 deg). Studies were made in February and March, so all animals used were adults. The mean of 25 performances by valley mice was 15.8 min; the mean of 22 performances by mountain mice was 7.5 min. The chief factor of difference between the two groups is in the reduced pO2 of the mountain environment and consequent hypoxia at this altitude. However, customary ambient temperatures are quite different, although room temperatures in which the animals were kept were similar. Although there is a possible differential effect of the same ambient temperature on the two mice populations, it was not discernible within each population except possibly in those trials run at over 20 C. Submitted on August 11, 1960
H+ and pCO2 as chemical factors in respiratory and cerebral circulatory control
Authors: Lambertsen C. J. , Semple S. J. G. , Smyth M. G. , Gelfand R. 
Published: December 2017

The relationships of changes in respiration and brain blood flow index to alterations in arterial and internal jugular venous blood pCO2, [HCO3-], and pH were studied in normal men. Observations during control of alveolar pCO2, first at 44 and then at 50 mm Hg, represented the effects of CO2 breathing. Intravenous infusion of NaHCO3 solution (ca. 2.4 mEq/kg) while maintaining alveolar pCO2 at 50 mm Hg revealed the responses to a lowering of blood [H+] without concurrent change in arterial or internal jugular venous pCO2. Brain blood flow index varied directly with alteration in blood pCO2 and was unaffected by changes in blood pH not produced by pCO2 change. Respiratory measurements indicated a prominent relationship between respiration and blood hydrogen ion concentration, the reversal of the acidemia normally associated with CO2 administration removing approximately 45% of respiratory stimulation induced by hypercapnia. The remaining 55% of the increased ventilation caused by CO2 breathing was not directly related to changes in arterial or internal jugular venous blood pH or [HCO3-]. The residual respiratory effect of CO2 administration was correlated, not only with alteration of pCO2, but with calculated changes in the pH of cerebrospinal fluid. Thus, the total respiratory stimulation produced by CO2 breathing, and its diminution by bicarbonate infusion, can be quantitatively described either in terms of a single stimulus index, hydrogen ion concentration, or in terms of two factors, pH and pCO2. Choice between single and multiple acid-base factors as indices of chemical stimuli in respiratory control remains arbitrary. However, the discussion re-emphasizes that, while respiratory changes do occur when blood pH is altered without change of blood or central pCO2, comparable stimulant effects of molecular CO2 cannot be demonstrated without somewhere producing concurrent modification of pH. Submitted on August 22, 1960
Causes of loss of consciousness during underwater swimming
Authors: Albert B. , Craig JR. 
Published: December 2017

Several incidents of losing consciousness while swimming underwater are known to the author. Experiments were designed to find out how this could happen. Four types of breath holding were executed: a) at rest, b) after hyperventilation, c) during mild exercise, and d) after hyperventilation and during exercise. At the breaking point the subject made a maximal expiration, and the end tidal air was analyzed for O2 and CO2. It was found that when the breaking point was reached, the Pco2 was higher and the Po2 lower during exercise than at rest. The lowest Po2 was observed after the subject had exercised following hyperventilation: the Po2 was 34 mm or below in 4 of the 12 subjects, a degree of hypoxia often associated with unconsciousness. Other experiments including underwater swimming support the conclusion that loss of consciousness after hyperventilation and during exercise is possible and is probably due to hypoxia. Submitted on December 30, 1960
Changes in erythrocytes resulting from excessive shrinking
Authors: Valdivieso Darío , Hunter F. R. 
Published: December 2017

A change occurs in chicken erythrocytes during suspension in salt solutions or solutions of nonelectrolytes in Locke-Ringer solution with an osmotic pressure three to four times that of the original cells. If the cells shrink and then swell in less than 10 min this change does not occur. The changed cells are more fragile than normal cells. They have less potassium but more sodium. Evidently when these erythrocytes shrink to a certain point there is some irreversible change. The mechanism for maintaining the cation imbalance between the cell and its environment can break down, and the cells can lose potassium and gain sodium. The cells are highly fragile, and consequently they hemolyze under various circumstances which are not hemolytic to normal cells. Submitted on November 14, 1960
Lung mechanics and resuscitation after fluid aspiration
Authors: Colebatch H. J. H. , Halmagyi D. F. J. 
Published: December 2017

Lung mechanics, arterial oxygen saturation (Sao2) and effective pulmonary capillary blood flow (Qe) were measured before and after intratracheal administration of 1—3 ml/kg body wt. of fresh or sea water in 20 intact and 11 vagotomized sheep during light thiopentone anesthesia. A gross fall in lung compliance (Cl) occurred in all animals after introduction of fresh and sea water; the fall was greater in intact than in vagotomized animals. A variable increase in nonelastic resistance was mainly due to blocking of airways by fluid and foam. Fall in Cl appeared to be the consequence of a reaction within the lungs resulting in a widespread closure of the terminal airways, which was influenced by the vagus nerve but not abolished by vagotomy. By relating Cl and Qe, hypoxemia induced by fluid was explained in terms of altered lung mechanics. Forced inflation increased Cl after fresh water and to a greater extent in vagotomized animals, but produced no change after sea water. A method of resuscitation is suggested based on the change in lung mechanics. With the use of 100% oxygen this method restored normal Sao2 independent of amount of fluid in the lung. Submitted on December 28, 1960
Effect of a previous deep inspiration on airway resistance in man
Authors: Nadel Jay A. , Tierney Donald F. 
Published: December 2017

We measured airway resistance and thoracic gas volume by the body plethysmograph technique, and transpulmonary pressure in seven healthy, adult subjects, before and after induction of bronchoconstriction. A deep inspiration never altered airway resistance, measured at functional residual capacity in the control state, but always reduced it for 1—2 min when bronchoconstriction was present. Discrepancies in data published on airway resistance may be due to use of methods which require a deep inspiration, or to occurrence of a spontaneous deep inspiration shortly before the test. Submitted on January 13, 1961
Localized multiple minute pulmonary embolism and breathing
Authors: Horres Alan D. , Bernthal Theodore 
Published: December 2017

During continuous spirometric recording of breathing, 75–μ glass bead emboli were delivered selectively to single lungs or lung lobes while the remaining lung areas were maintained functionally intact and free of emboli. Postmortem digestion of the lungs revealed the distribution of the emboli and demonstrated complete localization within single lungs or lobes in 12 of 16 experiments. In all instances the frequency of breathing increased and tidal air decreased in a pattern indistinguishable from that attending bilateral multiple minute pulmonary embolism. These effects were abolished by vagotomy but survived inhalation of pure oxygen. Comparison of the quantitative relationship between emboli dose and magnitude of response in localized with that in generalized pulmonary embolization suggests that, within limits, the intensity of the tachypnea is determined by the number of emboli injected regardless of the identity of the gross lung area in which they lodge or the degree of their concentration or dispersion within areas in which they lodge and seems not to favor associated hemodynamic factors as the agency initiating the reflex. Submitted on January 3, 1961
Cardiac oscillations in expired gas tensions, and regional pulmonary blood flow
Authors: Fowler K. T. , Read John 
Published: December 2017

Oscillations in expired gas tensions synchronous with the heartbeat were studied in detail following a tidal inspiration of a gas mixture containing 20.9% oxygen, 20% argon, and the rest nitrogen. A respiratory mass spectrometer continuously analyzed expired gas for argon, oxygen, and carbon dioxide. Simultaneous recordings of expiratory flow rate, expired volume, and electrocardiogram were made where necessary. The gas tension oscillations reflected pulsatile changes in gas flow from regions of different ventilations, blood flows, and Va/Qc ratios. An explanation for the oscillations was developed on the basis of cardiac-induced variations in relative gas flows from upper and lower zones of the lungs. This allowed the identification of these zones with the regions of different Va/Qc ratios, and the calculation of minimum differences in ventilation and blood flow between upper and lower lung zones. Blood flow in the upper lung zones of erect normal subjects was found to be very low, rising considerably on lying down. Three patients with raised left auricular pressures showed high upper zone blood flow in the erect position. Submitted on February 27, 1961
Estimates of cardiac output from forward part of indicator dilution curves
Authors: Thorburn Geoffrey D. 
Published: December 2017

A study was made of 135 dye-dilution curves, 77 of which were obtained from dogs and 58 from man. It was previously shown that the degree of asymmetry of indicator dilution curves varies with changes in flow, volume, and path length, and this has been found to influence the estimates of cardiac output made from the initial part of the curves by the forward triangle and Dow methods, and by a new method described in this paper. This variation may be minimized by the calculation of separate constants for each injection site and by keeping the variation in flow and volume as small as possible. Errors are likely to arise when these methods are used outside the range of the normal data. It has been found that this variation in asymmetry is mainly responsible for the scatter in the estimates of cardiac output using these methods. The agreement between the forward triangle and the Dow methods was found to be very close and the reason for this is discussed. Submitted on February 13, 1961
Restoration of circulation after fresh water drowning
Authors: Redding Joseph S. , Cozine Richard A. 
Published: December 2017

Lightly anesthetized dogs were subjected to obstructive asphyxia, simulating laryngospasm. After respiratory arrest the lungs were flooded with fresh water for 30 sec, according to a standardized experiment. Ten dogs were treated with intermittent positive-pressure artificial respiration with 100% oxygen. Six of the ten dogs suddenly developed ventricular fibrillation less than 2 min after artificial respiration was started. In these animals an artificial circulation was maintained for 20 min by repeated compression of the heart between the sternum and vertebral column. Then, after intravenous administration of hypertonic saline and epinephrine solutions, a 480-v shock was applied to the chest wall. In five of the six dogs there was an immediate resumption of spontaneous circulation. In an additional ten dogs ventricular fibrillation was produced by the same sequence of obstructive asphyxia and flooding of the lungs. In five, treatment was identical except that injection of hypertonic saline was omitted. Circulation was restored in four. In the remaining five, ventilation was performed with air. Restoration of circulation was successful in one. Submitted on June 12, 1961