bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood glucose metabolism in man during muscular work
Authors: Reichard G. A. , Issekutz Bela , Kimbel Philip , Putnam Richard C. , Hochella Norman J. , Weinhouse Sidney 
Published: December 2017

A resting human subject was given an intravenous injection of a “trace” dose of glucose-U-C14, and blood and respiratory CO2 samples were collected during ensuing rest, exercise, and rest periods. The CO2 was assayed for radioactivity, and the blood was assayed for total and radioactive glucose and lactate. Total O2 uptake and CO2 output were also measured. In the initial rest period, blood glucose and lactate remained constant while their specific activities declined exponentially. Immediately with onset of exercise, blood lactate level and CO2 excretion increased greatly, but their low specific activities in comparison with that of the blood glucose indicated their origin from endogenous substrates, presumably muscle glycogen. During the subsequent recovery period the specific activities of lactate and CO2 rose while the blood lactate and respiratory CO2 excretion dropped to normal levels. Although the level of blood glucose did not change markedly, its specific activity fell more rapidly during work than during rest, indicating a greater “turnover.” However, this increased turnover began some time after commencement of work and continued into the subsequent recovery period. These findings suggest that the stored muscle glycogen represents the immediate fuel for glycolysis and respiration of working muscle. Subsequently, there is an increased uptake of the blood glucose by working muscle, compensated in the present experiments by an increased hepatic glucose output. The data are in accord with previous suggestions that there is a mechanism whereby muscular work stimulates glucose uptake. Submitted on July 27, 1961
Voluntary changes in breathing pattern and N2 clearance from lungs
Authors: Bouhuys Arend , Lichtneckert Stefan , Lundgren Claes , Lundin Gunnar 
Published: December 2017

Lung N2 clearance curves were recorded in three normal and two symptom-free asthmatic subjects at breathing rates of 10—60/min and tidal volumes of 350—1,950 ml. A change toward more uniform gas distribution at larger tidal volumes was found in one subject. Changes in breathing rate did not affect gas distribution demonstrably. The washout ventilation per liter lung volume (lung clearance index) did not show significant changes with either breathing rate or tidal volume except for an increase at tidal volumes of less than 450 ml. These findings agree with the assumption of a constant dead space volume at tidal volumes within the range studied. The results are of practical importance for the use of the lung clearance index as a measure of the effect of broncho-active substances on the lung ventilation in man. Submitted on April 28, 1961
A cerebral decarboxylase for 5-hydroxytryptophane in humans
Authors: Sacks William 
Published: December 2017

Little or no cerebral decarboxylation of 5-hydroxytryptophane could be found using the in vivo technique developed in this laboratory for determination of human cerebral metabolism. Following intravenous injection of dl-5-hydroxytryptophanecarboxyl-C14 little or no significant venous-arterial C14O2 differences resulted in four normal control subjects and four chronic mental patients. No significant differences were found between the two groups. Levels of arterial blood C14O2 activities showed that 5-hydroxytryptophane was decarboxylated readily by other body tissues. Of four subjects pretreated with 1-benzyl-2-methyl-5-methoxytryptamine (BAS), slightly lowered results occurred with the mental patient pretreated with a double dose of BAS. Submitted on June 19, 1961
Liver lipid as a source of embolic fat
Authors: Owens Guy , Sokal Joseph E. 
Published: December 2017

Little attention has been focused on the liver as a source of embolic fat. Despite this, clinical observations are available suggesting a relationship between fatty livers and the frequency and/or degree of fat embolization. By combining whole organ perfusion techniques and dietary production of fatty livers in experimental animals, a tool for evaluating the liver and its role in fat embolization has been developed. Fatty livers were produced in adult rats within 12 days by employing a high fat choline-free diet. One group of animals so prepared served as nonperfused tissue controls. Livers from normal and special dietary animals were removed and perfused for periods up to 4 hr. All tissues were frozen and then sectioned after 24-hr fixation in 10% formalin and stained with flaming red and hematoxylin. Nonperfused livers from animals on a choline-free diet revealed intense intracellular lipid concentration, but no fat emboli. Normal livers perfused for 3—4 hr were free of significant accumulation of embolic fat. In contrast, severe embolization was encountered in the perfused fatty livers. Note: With the Technical Assistance of Kornel Gerszi and Mary S. Northington Submitted on May 10, 1961
Quantitative assessment of body build
Authors: Behnke Albert R. 
Published: December 2017

A quantitative classification of body build is outlined for adolescents and adults based on 11 circumferences and 8 diameters which can be converted by division with appropriate constants into d quotients. Selected d quotients are then placed in three categories, d( A), d( B), and d( C), which indicate numerically degree of fatness ( A), muscularity ( B), and skeletal size ( C). Equivalent weights, W( A), W( W), and W( C) can be derived from d( A), d( B), and d( C), and in fractional proportions add up to body weight. The anthropometric rating is in terms of A, B, and C, each component related to the other two. The A and B components derived from circumferences can be related directly to body weight. The C component based on skeletal diameters requires further evaluation in relation to chemical and biophysical analysis of body structure. The d quotients when related to body weight or lean body weight provide the basis for a somatogram which depicts intraindividual variations of the various measured parameters as deviations from (See PDF). The system with invariant conversion constants, specific for each sex, has been adequate to describe numerically the fat, muscular, and skeletal components of body build both in the male and female over an age range of 14—93 years, and with variation in stature from 150 to 200 cm and in weight from 40 to 150 kg. Submitted on June 5, 1961
Influence of unilateral endurance training on contralateral limb
Authors: Hodgkins Jean 
Published: December 2017

Forty-one women college students were tested to determine the effect of unilateral endurance training on the contralateral limb. Endurance was defined as the maximum number of times a subject, seated on a table, could lift an 18-lb boot from one prescribed point to another at a given rate of speed. Initial endurance of the quadriceps muscle group in each leg was established. For the next 3⅓ weeks each subject trained three times a week to increase endurance in one leg. At the end of the training period the endurance of the untrained limb was again tested. Through training, the mean increase in endurance of the active limb was 435.71 or 966%. The mean increase in endurance of the inactive or untrained limb was 145.34 or 275%. Submitted on April 17, 1961
Effect of body temperature reduction on response acquisition in mice
Authors: Essman Walter B. , Sudak Frederick N. 
Published: December 2017

In four experiments designed to determine the effects of a moderate reduction of body temperature on response acquisition mice were treated with either 2,4-dichlorophenoxyacetic acid or saline in combination with cold exposure. In a four-trial water-escape problem, normothermic animals acquired the response but hypothermic mice did not show learning. A temperature-dependent relationship to learning was demonstrated. Note: (With the Technical Assistance of J. R. Blumstein)
Effect of body posture on gas distribution in the lungs
Authors: Bouhuys Arend , van Lennep Hans J. 
Published: December 2017

Postural changes of functional residual capacity (FRC) and pulmonary N2 clearance efficiency were studied in six male subjects placed supine on a tilting table, in head-up, horizontal and head-down positions. FRC varied linearly with the angle of tilt. The lung clearance index (LCI) increased significantly in the supine and head-down positions, compared to the head-up positions, which indicates less uniform gas distribution in the former postures. This was confirmed by analysis of semilogarithmic graphs of N2 washout. Inhalation of epinephrine did not affect the postural changes of FRC and LCI, but caused a small increase of LCI irrespective of posture. The increased uneven distribution in head-down and supine positions is probably a consequence of the lung volume decrease in these postures, and may be explained by mechanical factors such as surface tension, which tend to close lung units when the lungs are deflated. Bronchomotor tone has no appreciable influence on these postural changes in normal subjects. Submitted on July 13, 1961
Correlation of hemodynamic events during infusion of epinephrine in man
Authors: Allwood Michael J. , Keck Ernst W. , Marshall Robert J. , Shepherd John T. 
Published: December 2017

Changes in cardiac output, stroke volume, and systemic blood pressure have been correlated with changes in muscle blood flow during the periods of initial transient and subsequent sustamed vasodilatation during intravenous infusion of epinephrine. In the initial phase blood pressure decreased slightly; forearm blood flow increased by 308%, cardiac output by 50%, and stroke volume by 10%. During the sustained phase the systolic blood pressure increased; corresponding increases for the other measurements were 87, 47, and 25%, respectively. The lack of correlation between these changes in cardiac output and forearm blood flow suggests that in the transient phase vasodilatation does not occur simultaneously in all muscle groups. Stroke volume makes a greater contribution to the increased output during the sustained phase. Submitted on May 29, 1961
Effect of mild hypoxia on ventilation during exercise
Authors: Hornbein Thomas F. , Roos Albert 
Published: December 2017

Hypoxia of mild degree (PaOO2 above 60 mm Hg) produces little or no ventilatory response in resting man during the steady state. To evaluate the possibility that the effectiveness of a hypoxic chemoreceptor drive might be enhanced by exercise, the ventilatory response to mild hypoxia was measured in two human subjects during rest and exercise. Though no significant increase in ventilation occurred at rest above a PaOO2 of 60 mm Hg, a decrease in PaOO2from 100 to 94 mm Hg produced a statistically significant increase in steady state ventilation during moderate exercise. In addition, temporary block of the sympathetic innervation to the carotid and aortic bodies in one subject resulted in a diminution of work hyperpnea. This suggests that increased sympathetic tone during exercise, by reducing blood flow through the chemoreceptors, might result in increased neural discharge and hence increased ventilation even though arterial POO2 is the same as at rest. Thus, activity of the chemoreceptors as modified by sympathetic control of their blood supply may be an important determinant of the ventilatory response to exercise. Since work hyperpnea is enhanced by even mild hypoxia, this ventilatory response may be sufficient to initiate respiratory acclimatization to altitudes so low that resting ventilation on acute exposure is unaffected. Submitted on July 31, 1961
Primary hypocapnia: a cause of metabolic acidosis
Authors: Eichenholz A. , Mulhausen R. O. , Anderson W. E. , MacDonald F. M. 
Published: December 2017

In the presence of severe, sustained hypocapnia produced in dogs by mechanical hyperventilation, a bicarbonate deficit has been observed. The development of this deficit was progressive and did not terminate at pH compensation. The consequence of this progressive deficit was metabolic acidosis. Simultaneous with the increasing bicarbonate deficit, a rise in lactic and pyruvic acids was observed. Most of the bicarbonate deficit could be accounted for by the rise in the organic acids. In a series of experiments in which pH and pCO2 have been independently controlled, the rise in lactic and pyruvic acids was only associated with reduced pCO2. No rise in lactic and pyruvic acids occurred during hypoxia unless associated with hypocapnia. The rise in lactic and pyruvic acids plays a major role in the compensation for respiratory alkalosis. This process of compensation, although homeostatic in regard to pH, may be considered a pathologic state characterized by a progressive bicarbonate deficit. This deficit may be extensive enough to result in metabolic acidosis. Note: (With the Technical Assistance of J. Sellner, C. Pfeffer, and D. Larson) Submitted on November 29, 1961
Some effects of breath holding and apneic underwater diving on cardiac rhythm in man
Authors: Olsen C. Robert , Fanestil Darrell D. , Scholander Per F. 
Published: December 2017

Man's bradycardic response to simple breath holding was augmented by submersion in water of 27 C and was not prevented by muscular exercise. Cardiac arrhythmias occurred with 45 of 64 periods of apnea in 16 subjects and were more frequent during the dives than during breath holding. These arrhythmias, with the exception of atrial, nodal, and ventricular premature contractions, were inhibitory in type and included sinus bradycardia and arrhythmia, sinus arrest followed by either nodal escape or ventricular escape, A-V block, A-V nodal rhythm, and idioventricular rhythm. T waves frequently became tall and peaked during both breath holding and dives. Prompt return to normal sinus rhythm was the rule with the first breath after surfacing. Sinus tachycardia, sinus arrhythmia, and atrial, nodal, or ventricular premature contractions were seen during recovery. Submitted on October 9, 1961
Effect of arterial pressure on arterial and venous resistance of intestine
Authors: Johnson Paul C. , Hanson Kenneth M. 
Published: December 2017

The effect of local alteration of arterial pressure on arterial and venous resistance of the intestine was investigated by means of the Pappenheimer isogravimetric technique. Reduction of arterial pressure caused a decrease in total vascular resistance in 70% of the experiments (autoregulation). This response was localized to the arterial portion of the circuit, specifically to vessels less than 0.5 mm o.d. Also associated with the reduction in arterial pressure was an increase in venous resistance. Venous resistance increased threefold as arterial pressure was reduced from 100 to 30 mm Hg. This venous response was seen in all preparations tested. It is suggested that both the venous response and autoregulation of arterial vessels aid in maintenance of a normal capillary pressure. Submitted on November 6, 1961
Arterial oxygen saturation during exercise at high altitude
Authors: West J. B. , Lahiri S. , Gill M. B. , Milledge J. S. , Pugh L. G. C. E. , Ward M. P. 
Published: December 2017

Arterial oxygen saturations were measured on six members of the Himalayan Scientific and Mountaineering Expedition, 1960–61, during a wintering period at 19,000 ft (5,800 m; Pb 380 mm Hg). The determinations were made by ear oximetry and by the analysis of venous blood from the heated hand during rest and exercise at work levels up to 1,200 kg-m/min. Expired gas volumes and gas concentrations were also measured. The average arterial oxygen saturation at rest was 67%, and at work levels of 300 and 900 kg-m/min it was 63 and 56%, respectively. Several readings of less than 50% saturation were recorded during severe exercise. The progressive fall in arterial oxygen saturation as the work level was raised occurred in spite of an increasing alveolar oxygen tension, and the resulting large alveolar-arterial oxygen differences can be explained by the diffusion limitations of the lung. Submitted on January 12, 1962
Intravascular and intracardiac blood temperatures in man
Authors: Afonso Skoda , Rowe George G. , Castillo Cesar A. , Crumpton Charles W. 
Published: December 2017

Intracardiac and intravascular blood temperatures were measured in a group of 17 afebrile patients undergoing cardiac catheterization. Using a cardiac catheter with a thermistor mounted at the tip, measurements were made in the following locations: different levels of the inferior vena cava, the superior vena cava, the renal, hepatic, and internal jugular veins, the right atrium, pulmonary artery and pulmonary artery wedge position, coronary sinus and right ventricle, and the left atrium and pulmonary veins (in subjects with atrial septal defects or patent foramen ovale). Data obtained confirm and extend observations made by other investigators. The blood temperature in the pulmonary artery, pulmonary artery wedge, left atrium, and pulmonary vein were found to be very nearly the same. Furthermore, temperature recordings made in different sites of the inferior vena cava, superior vena cava, right atrium, and pulmonary artery show variations phasic with respiration. The mechanism of these thermal variations is discussed. Submitted on February 5, 1962
Minute ventilation as a measure of energy expenditure during exercise
Authors: Malhotra M. S. , Ramaswamy S. S. , Ray S. N. , Shrivastav T. N. 
Published: December 2017

Studies were made on energy expenditure (E) and minute ventilation (MV) during performance of various military and other tasks by 58 subjects with 495 observations. The capacity for oxygen extraction varies between individuals depending on their physical development and working habits. It is suggested that for determining energy expenditure from minute ventilation, it is necessary to group the individuals on the basis of duty or occupation. For each group, a relationship has to be worked out between E and MV, after taking 16 observations on different subjects. This relationship (max. error ± 4.7%) can then be utilized for field surveys within that group without any further gas analyses. For Indian soldiers E = 0.215 x MV; for Indian Olympic hockey players E = 0.273 x MV. Submitted on October 24, 1961
Resting arteriovenous oxygen difference and exercise cardiac output
Authors: Thomas H. Duke , Gaos Carlos , Reeves T. J. 
Published: December 2017

Measurements of the cardiac output utilizing the classical Fick method were carried out in 38 cardiac patients at rest and during exercise. The predicted cardiac output during exercise was calculated by the regression equation derived by Donald et al. ( Clin. Sci. 14: 37, 1955), relating cardiac output to oxygen consumption during the steady state of exercise in normal subjects (cardiac index = 3.708 + 0.00534 x O2 consumption, ml/min m2). The resting arteriovenous oxygen difference was found to correlate much better with the calculated percentage of predicted cardiac index during exercise (γ = 0.547) than did the resting cardiac index (γ = 0.304). The finding of an arteriovenous oxygen difference greater than 5.16 ml/100 cc indicated a strong probability of subnormal cardiac index during exercise relative to the oxygen consumption. Submitted on June 18, 1962
Effect of shape-volume changes on uptake of CO and O2 by hemoglobin in erythrocytes
Authors: Sirs John A. 
Published: December 2017

Spectrophotometric measurements have been made of the effect of variation of the ionic strength, and equivalent molar concentration of sucrose, on the rate of uptake of CO and O2 by reduced erythrocytes. Cyclic variations of the rate of uptake by as much as 30% have been observed as the ionic strength is altered. The rate of uptake under these conditions is not proportional to the gas concentration. An analysis of these effects suggests the predominant factor is shape-volume changes which alter the membrane permeability. Similar observations have been made on the effect of pH variations. An optimum rate of uptake occurs at pH 7.4. Submitted on September 21, 1961
Pulmonary diffusing capacity for CO and hemodynamic changes in isolated perfused cats' lungs
Authors: Duke Helen N. , Rouse W. 
Published: December 2017

The diffusing capacity for CO (Dco) measured in isolated blood-perfused cats' lungs by a modified steady-state method is 0.7 ml/mm Hg min (sd ± 0.25 ml/mm Hg min). The Dco is increased by increasing the rate of pulmonary arterial inflow or by increasing the left atrial pressure at constant rate of pulmonary arterial inflow. Reduction of left atrial pressure or pulmonary arterial inflow rate under the same conditions reduces the Dco. The Dco is closely related to pulmonary arterial pressure, mean pulmonary vascular pressure, and pulmonary vascular resistance. Changes of pressure and resistance have similar effects on Dco, whether they are produced by alterations of left atrial pressure or pulmonary arterial inflow rate. Submitted on April 6, 1962
Evidence that the Pco2 of mixed venous blood is not a regulator of ventilation during exercise
Authors: Storey Winnifred F. , Butler John 
Published: December 2017

We studied 10 patients with intracardiac left-to-right shunt and 13 patients with other cardiac lesions during exercise. The hyperpnea of muscular exercise was independent of the mixed venous Pco2. In the 13 patients without shunt both the pulmonary arterial Pco2 and the ventilation increased during exercise. In the 10 patients who had shunts ventilation increased during exercise even when the Pco2 in the pulmonary arterial blood did not rise. Submitted on July 5, 1962
Lung volumes and ventilatory responses to high CO2 and low O2 in the ama
Authors: Song S. H. , Kang D. H. , Kang B. S. , Hong S. K. 
Published: December 2017

Various respiratory functions were determined in 20 ama (diving women) as well as in an equal number of nondivers (control group.) The vital capacity was significantly larger in the ama than in the control; this is entirely due to the higher inspiratory capacity in the former group. Neither the residual volume (RV) nor the expiratory reserve volume showed any difference between the two groups. Hence, the RV/TLC ratio tended to be lower in the ama. MBC was considerably higher in the ama. The maximal inspiratory pressure for any given lung volume was significantly higher in the ama, while the maximal expiratory pressure was not different between the two groups. The resting alveolar gas composition is not different from that of the control. The ventilatory responses to breathing 3% and 5% CO2 in O2, as well as the ventilatory responses to breathing 8.5% O2 in N2, were measured and are discussed. It is suggested that some of these differences in pulmonary function between the ama and control group represent long-term adaptations of the divers acquired by engaging daily in diving operations. Submitted on September 28, 1962
Bradycardia in human divers
Authors: Irving Laurence 
Published: December 2017

Electrocardiograms showed bradycardia developing in men and women during apnea in air and more markedly when submerged in water. Intervals between heartbeats reached 2 sec. The onset and degree of bradycardia were not reduced by vigorous swimming underwater. The bradycardia appeared with more regularity and in greater degree in practiced and capable swimmers. The rapidity of onset of this bradycardia indicates that, as in many natural diving animals, it is reflexly initiated. Submitted on September 4, 1962