bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature regulation of Eskimos, Indians, and Caucasians in a bath calorimeter
Authors: Milan Frederick A. , Hannon John P. , Evonuk Eugene 
Published: December 2017

Eighteen men: six Alaskan Eskimos, six Arctic Athapascan Indians, and six Caucasian U. S. soldiers were immersed serially in a bath calorimeter where the rates of heat production and loss were measured during whole-body exposure to water temperatures of 35, 33, and 30.5 C. At each of these temperatures the Eskimos exhibited the highest rates of heat production and loss, followed by the Indians and Caucasians in decreasing order. Duplicate basal metabolic rate measurements averaged 46 kcal/hr m2 in the Eskimos, 42.5 kcal/hr m2 in the Indians, and about 37 kcal/hr m2 in the Caucasians. Body fat percentages calculated by the skin-fold method were: Eskimos, 6.6%; Indians, 12.3%; and Caucasians, 15.6%. Calculations showed the Eskimos had the lowest tissue insulation followed, respectively, by the Indians and Caucasians. Calculations showed the lower insulation in the Eskimos was independent of their lack of body fat and probably reflected a greater peripheral blood flow. Since the rectal temperature decrements during immersion were the same in all three groups, it was concluded that the surface temperature gradients extended more deeply in the Eskimos than in the other two groups. Hence, they could be described as having smaller “cores” and larger “shells” than either the Indians or the Caucasians. Submitted on August 27, 1962d
Absorption by an in vitro preparation of dog intestinal mucosa
Authors: Hakim Ali , Lester R. G. , Lifson N. 
Published: December 2017

Sheets of dog small intestinal mucosa consisting of only epithelium and lamina propria were mounted for in vitro study. The following transport behavior characteristic of the intestine was found: a) dependence of water transport from isotonic Ringer's fluid on the presence of glucose in the medium, b) water absorption against an osmotic activity difference, c) sensitivity of water transport to small excess hydrostatic pressure on the serosal side, d) uphill glucose movement, and e) chloride impoverishment. Submitted on October 24, 1962
Direct measurement of respiratory pleural pressure changes in normal man
Authors: Daly Walter J. , Bondurant Stuart 
Published: December 2017

Using a specially designed needle system, pressures were recorded directly from the pleural space in seated normal men. Respiratory pressure changes (ΔP) measured simultaneously from different pleural sites and the esophagus are not the same but become so after a large pneumothorax is produced. Since esophageal ΔP is little affected by a pneumothorax of 2–300 ml, it is suggested that, in the absence of pneumothorax, esophageal ΔP represents a better measure of the over-all elastic behavior of the lung than any local pleural ΔP. In the absence of pneumothorax, ΔP is less in the upper than in the lower chest. This may be an expression of a gradient either of distribution of ventilation or of elastic forces opposing expansion of the lung. In three of four subjects, end expiratory pressure was more positive in the low chest than in the high chest. Acute central vascular engorgement (pressure suit inflation) caused similar changes in esophageal and intrapleural ΔP. These observations confirm the previously observed decrease in lung compliance during acute central vascular engorgement and provide evidence of local differences in respiratory pleural pressure change in man. Submitted on August 20, 1962
Changes in compliance in rabbits subjected to acute bronchoconstriction
Authors: Anthonisen Nicholas R. 
Published: December 2017

The pulmonary mechanics of anesthetized rabbits were studied during induced acute bronchoconstriction. The bronchoconstricting agent was acetyl-β-methylcholine which, when injected intravenously as in these experiments, appeared to act via the pulmonary circulation. In spontaneously breathing animals functional residual capacity increased with bronchospasm, and dynamic compliance decreased. This decrease correlated in magnitude with the severity of the bronchoconstriction. Frequency changed in random direction. Dynamic compliance recovered more slowly than conductance after bronchoconstriction unless the lungs were inflated just prior to each recovery measurement, in which case the two variables recovered equally quickly. This observation suggested that airway occlusion accounted for part of the decrease in dynamic compliance. Bronchoconstriction reduced semistatic compliance in paralyzed artificially ventilated animals and also static compliance, which was measured by arresting breathing with phrenic stimulation, in spontaneously breathing animals. These observations supported the above hypothesis. Submitted on September 26, 1962
Mechanism and pharmacology of endotoxin shock in sheep
Authors: Halmagyi D. F. J. , Starzecki B. , Horner G. J. 
Published: December 2017

The cardiopulmonary consequences of coli-lipopolysaccharide and staphylococcus toxin administration were studied in sheep. Circulatory changes consisted mainly of a marked rise in pulmonary arterial and pulmonary arterial wedge pressure (with left atrial pressure unchanged), and a fall in cardiac output and in systemic arterial pressure. Fall in the latter closely followed the onset of pulmonary hypertension. The respiratory response consisted mainly of a severe fall in lung compliance produced by terminal airway closure. Continued perfusion of the nonventilated alveoli resulted in venous admixture. Premedication with antihistaminic, antiserotonin, or adrenolytic agents failed to affect the response. Norepinephrine or hypertensin administered after toxin injection had virtually no effect while isoproterenol treatment reduced pulmonary arterial pressure, increased cardiac output, arterial oxygen saturation, and, in cases of endotoxin shock, promptly raised systemic arterial pressure. Endotoxin-resistant sheep proved nonresponsive to minor pulmonary embolism and to incompatible blood transfusion. It is suggested that a common mediator agent is responsible for the similar cardiopulmonary consequences of these three diverse conditions. Submitted on November 26, 1962
Metabolic response to cold air in men and women in relation to total body fat content
Authors: Buskirk Elsworth R. , Thompson Ronald H. , Whedon G. Donald 
Published: December 2017

Eight healthy young men (ages 19–35), four older men (ages 38–42), three obese subjects (two women and one man, ages 20–34) were individually exposed on one or more occasions to 10 C (50 F) air in the Metabolic Chamber for periods of 2–4 hr. A minimal amount of clothing was worn: the males wore shorts and the females wore halters and shorts. Air movement was routinely less than 50 ft/min and relative humidity 50% or less. Body fatness among the subjects ranged from 13 to 45% of body weight. The metabolic response to cold determined from Vo2 and Vco2 was significantly and inversely related to per cent body fat according to the regression equation: kcal/(m2·hr) = 65.2 – 0.520 (% fat) ± 0.115. Total body insulation after 2 hr of exposure was significantly and directly related to per cent body fat and inversely related to the metabolic response. Despite these significant relationships, wide individual differences were observed in the metabolic response to cold between pairs of subjects of like age, previous history of cold exposure, and body fatness. Submitted on September 27, 1962
Bronchial pressures and dimensions in health and obstructive airway disease
Authors: Macklem Peter T. , Fraser R. G. , Bates D. V. 
Published: December 2017

Bronchial pressure, esophageal pressure, and flow at the mouth were measured during cinebronchography in three normal subjects, three patients with emphysema, and one subject with intermittent bronchospasm. Each cineframe exposure generated an electrical signal which was recorded simultaneously with pressures and flow. Since the bronchial catheter had a 1-cm radio-opaque tip, bronchial diameters were obtained simultaneously with bronchial pressure, esophageal pressure, and flow. By this technique the pressure drop down the bronchial tree during forced expiration was measured. In normals, although greater than 50% of the total pressure was required to produce flow from the right lower lobe bronchus to the mouth, the pressure drop down its length alone was only 2–15% of the total, whereas in emphysema it was 35–85% and was associated with collapse of this bronchus. The narrowing of large bronchi, in particular those with posterior membranous sheaths, is thus a factor in limiting expiratory flow in normal subjects. In the three patients with emphysema the collapsing right lower lobe bronchus impeded emptying of the lower lobe during forced expiration, apparently due to an increase in the compliance of this bronchus. Submitted on November 15, 1962
Variability of magnitude of the Bohr effect in human fetal blood
Authors: Kirschbaum Thomas H. 
Published: December 2017

A series of in vitro determinations, conducted on human fetal blood obtained at the time of delivery, of percentage oxyhemoglobin saturation, partial pressure of oxygen, and pH have made possible the evaluation of the magnitude of the Bohr effect in that substance. Analysis shows that the Bohr effect, defined as Δ log pO2/ΔpH, is a variable function of percentage oxyhemoglobin saturation over the statistically significant range in this study, from 10 to 87% saturation. The implications of this variability in terms of the molecular alterations of hemoglobin in the course of progressive oxygenation and in particular regard to the manifest heterogenicity of heme with respect to oxygen-acid radical interactions are discussed. Submitted on August 13, 1962
Thermal indicator sampling and injection sites for cardiac output
Authors: Mohammed Shakil , Imig Charles J. , Greenfield Elisha J. , Eckstein John W. 
Published: December 2017

The effects of indicator sampling and injection sites on estimation of cardiac output by the thermal dilution method were investigated in dogs. Dilution curves were recorded simultaneously with thermistors in the aortic arch and carotid or femoral artery after injection of indicator into the right atrium. The outputs calculated from carotid and femoral curves were higher than those from aortic curves. Nevertheless, the carotid and femoral arteries were considered satisfactory sampling sites because it was possible to predict aortic values from peripheral curves with a small range of error. The effect of indicator injection sites was studied by comparing outputs calculated from aortic curves after alternate injections into the right atrium and external jugular vein. The outputs calculated after jugular injections were higher. The external jugular vein was considered to be a less desirable injection site because the correlation between aortic values obtained after injections into the two sites was relatively low, and the predictability of one value from the other was not good. Submitted on January 14, 1963
Relation of local skin temperature and local sweating to cutaneous blood flow
Authors: Senay Leo C. , Prokop Leon D. , Cronau Leslie , Hertzman Alrick B. 
Published: December 2017

The relationship of local skin temperature and the onset of sweating to the local cutaneous blood flow was studied in the forearm and calf. The purpose of the investigation was to appraise the possible relation of sweat gland activity to the cutaneous vasodilatation which has been attributed to bradykinin or to intracranial temperatures. The onset of sweating was not marked by any apparently related increases in the rate of cutaneous blood flow. On the contrary, the onset of sweating was followed often by a stabilization or even a decrease in the level of cutaneous blood flow. The relations of the latter to the local skin temperature were complex, particularly in the forearm. There appeared to be additional unidentified influences, possibly vasomotor, operating on the skin vessels during transitional phases in the relation of skin temperature to blood flow. Submitted on October 15, 1962
Relationship of increased breath-holding diffusing capacity to ventilation in exercise
Authors: Ross Joseph C. , Reinhart Ronald W. , Boxell John F. , King Leroy H. 
Published: December 2017

Pulmonary diffusing capacity (Dl), as measured by all techniques, increases with exercise possibly due to an increase in the volume of blood in pulmonary capillaries (Vc), but the mechanism for the latter is not known. Previous studies have indicated that the steady-state Dl can be increased by hyperventilation alone, enough possibly to account for the increase in Dl as measured by this method with exercise. On the other hand, breath-holding Dl is not increased by voluntary hyperventilation preceding the measurement. The present study was carried out to determine whether or not the increase in ventilation rate is a necessary part of a combination of factors which account for the rise in Dl during exercise. In this study breath-holding Dl was measured in five subjects. All of the five subjects studied had an increase in Dl during exercise when ventilation was voluntarily restrained to the resting level, and the mean increase was as great as the mean increase during the same amount of exercise with normal unrestricted breathing. The increase in Dl when breathing was restricted during exercise could not be accounted for by differences in alveolar volumes or by differences in alveolar O2 and CO2 tensions in the two situations. This study demonstrates that increase in ventilation preceding the measurement is not a determinant of the increase in breath-holding Dl with exercise Submitted on January 7, 1963
Oxygen cost of treadmill walking
Authors: Workman J. M. , Armstrong B. W. 
Published: December 2017

The development is described of an equation to predict the energy cost of treadmill walking of adult males. Oxygen consumption during level walking is considered as the product: oxygen consumption per step · number of steps per minute. At any given speed within the domain of the variable, number of steps per minute is then found to be a reciprocal function of height, and oxygen consumption per step a function of body weight. Rearrangement of the mathematical expressions that describe these relationships permits the calculation of oxygen consumption of level walking as the product of two constants, Pw, a constant for the individual; and Ks, a constant for the speed. It is suggested that these constants may have other uses besides the prediction of oxygen consumption of level walking. Oxygen consumption of grade walking is considered as the excess of oxygen consumption over that observed walking on the level at the same speed. This should be, but apparently is not, simply related to body weight. In a test of its predicting power, the equation predicted the oxygen consumption of 84 treadmill walks of 44 subjects, with a correlation coefficient measured: predicted values, γ = + 0.935. Submitted on October 26, 1962
A new renal artery clamp and applicator
Authors: Mulieri Louis A. , Korol Bernard 
Published: December 2017

A modification in the design of the Goldblatt renal artery clamp and a description of a new single unit applicator-adjuster are presented. Detailed construction diagrams as well as a description of operative technique are given. The new clamp and applicator were used extensively in preparing a colony of renal hypertensive dogs in our laboratories. The results were excellent and the operative time and difficulties were reduced. Submitted on February 14, 1963
Continuous recording of arteriolar dimensions with a television microscope
Authors: Wiederhielm Curt A. 
Published: December 2017

A system which permits continuous recording of dimensions of microscopic blood vessels is described. The system utilizes information contained in the video signal of a television microscope to develop an analog voltage proportional to the time required for the electron beam to sweep across the image of the blood vessel. This time interval is also proportional to the dimension of the vessel. Calibration of the system yielded a standard error of estimate of ±3.7 μ on a series of glass capillaries, ranging in size from 15 to 150 μ. The rise time of the system was in the order of 40 msec. Long- and short-term drift was less than 3 μ/hr. The system is used in an experimental study of viscoelastic properties of small arteries and arterioles. microcirculation; viscoelastic properties; frog mesentery Submitted on April 17, 1963
Ventilatory capacity during prolonged exposure to simulated altitude without hypoxia
Authors: Ulvedal F. , Morgan T. E. , Cutler R. G. , Welch B. E. 
Published: December 2017

Studies have been conducted in a sealed environment altitude chamber to study the chronic effect of reduced barometric pressure without reduced oxygen tension on human respiratory function and other physiological processes. Experiments were conducted at ground level, at 18,000 ft equivalent altitude (pO2 150 mm Hg), at 27,000 ft equivalent altitude (pO2 243 mm Hg), and at 33,500 ft equivalent altitude (pO2 174 mm Hg). Results were as follows: 1) Tests of pulmonary functions which are dependent on high volume flow rates are increased at altitude. These tests include maximum breathing capacity (increased 37% at 33,500 ft) and per cent of forced vital capacity during the first second of effort. 2) Expiratory minute volume was unchanged at altitude when oxygen partial pressure was maintained. 3) Forced vital capacity was reduced 3.1% at 18,000 ft, 2.9% at 27,000 ft, and 7.6% at 33,500 ft. This result was not due to hypoxia or abdominal distention and confirms the earlier findings of Rahn and Hammond. The cause of this change remains obscure but may be related to decreased lung volume. 4) The magnitude of changes observed appears to be somewhat proportional to altitude. Evidence is presented to relate increases in the flow-dependent tests to reduced density and reduced turbulent flow in the respiratory passages. respiratory physiology; sealed environment; spacecraft; atmosphere selection; space medicine Submitted on October 22, 1963
Lactate, pyruvate, glucose, and free fatty acid in mixed venous and arterial blood
Authors: Harris P. , Bailey T. , Bateman M. , Fitzgerald M. G. , Gloster J. , Harris E. A. , Donald K. W. 
Published: December 2017

The concentrations of lactic acid, pyruvic acid, glucose, and free fatty acids have been measured simultaneously in the blood from the pulmonary and brachial arteries at rest and during exercise in a group of patients with acquired heart disease. The arteriovenous differences in the concentration of lactate, pyruvate, and free fatty acid were such as could be attributed to chance. The average concentration of glucose was slightly but significantly higher in the brachial arterial blood than in the mixed venous blood. cardiac output; lung metabolism; exercise Submitted on January 15, 1963
Body composition and serum electrolyte concentrations
Authors: Boling E. A. , Lipkind J. B. 
Published: December 2017

Total exchangeable potassium, total exchangeable sodium, and total body water were simultaneously measured by dilution of K42, Na24, and H3, respectively. Total exchangeable chloride was estimated at the same time by dilution of Br82. The concentrations of water, sodium, potassium, and chloride were measured in the serum. The subjects included three healthy young men. The remaining 65 subjects were patients, with illness associated with disorders of nutrition and of water and electrolyte metabolism ranging from cachexia to extreme obesity and from dehydration to massive anasarca. The results show that in this highly varied group of subjects, neither Nae, Ke, nor Cle was correlated at all well with total body water when considered singly. Cle, in fact, was not considered to add useful information in the absence of information regarding other anions. However, the sum of Nae and Ke correlated exceedingly well with total body water (r = .991). Additional relationships containing serum cation concentrations had even higher degrees of correlation. Furthermore, it was found that expressions capable of predicting Nae or Ke could be derived from the data. Similarly high degrees of correlation were found when these regressions were computed for data from the literature. Note: With the Technical Assistance of E. Rossmeisl, R. McLean, H. Alpert, M. Halpin, and R. Gardner total body water; total exchangeable potassium; total exchangeable sodium; total exchangeable chloride Submitted on January 24, 1963
Functional evaluation of isolated perfused rat kidney
Authors: Bauman Arthur W. , Clarkson Thomas W. , Miles Ellen M. 
Published: December 2017

A technique for perfusing the isolated rat kidney with heparinized whole blood is described. Numerous aspects of renal function are evaluated. Blood and urine flows approximated normal limits occasionally but diminished and increased, respectively, with time. The reabsorption rates of osmoles, sodium, chloride, potassium, lactate, and phosphate were proportional to the filtered loads. Variations in filtered load were due mainly to changes in glomerular filtration rate (GFR). Tubular secretion of p-amino hippuric acid varied with the GFR, and TmPAH per milliliter GFR was 60% of in vivo values. Glucose reabsorption was practically complete. Urine osmolalities, initially in the range 400–1,000 mosmoles/liter, fell during a perfusion, often to values well below plasma levels. Postperfusion histologic studies usually showed slight to moderate tubular dilatation. It was concluded that: 1) The handling of individual ions approximated in vivo function. 2) Changes in GFR and in the rate of excretion of PAH represented changes in the number of active nephrons. 3) Low urine osmolalities were due to decreasing ability of the nephrons to reabsorb water. blood and urine flow; electrolyte excretion Submitted on February 25, 1963
Response of normal subjects to prolonged high fluid intake
Authors: Habener Joel F. , Dashe Alfred M. , Solomon David H. 
Published: December 2017

In order to test the hypothesis that the great variability seen in the serum osmolality characteristic of different normal persons is a result of fluid intake habits, four healthy male subjects ingested increasing amounts of fluid over a 4-week period reaching an average daily intake of approximately 8.5 liters during the 4th week. Serum osmolality measured repeatedly in the early morning and during weekly 6.5-hr water-deprivation tests did not vary significantly from that of control periods. It is concluded that in normal individuals fluid intake does not influence the “setting” of serum solute concentration. serum osmolality homeostasis; serum solute concentration in water loading; water intoxication; renal concentrating capacity; fluid balance; water regulatory mechanisms Submitted on June 25, 1963
A nomogram for predicting treadmill-walking oxygen consumption
Authors: Workman John M. , Armstrong Bruce W. 
Published: December 2017

In the course of an analysis of the metabolic cost of treadmill walking, an equation was derived that predicts the walking oxygen consumption of adult males in terms of subject's height and weight, and of treadmill speed and grade. A nomogram has now been developed, based on this prediction equation, that may also be used to preset the treadmill to obtain a given exercise oxygen consumption. exercise; metabolic rate; nomogram; treadmill walking Submitted on May 20, 1963