bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy and electrolyte metabolism and adrenal responses during work in dogs
Authors: Young D. R. , Price R. , Elder N. E. , Adachi R. R. 
Published: December 2017

Studies with dogs were undertaken to determine whether nitrogen metabolism during aerobic treadmill running is affected by recency of food intake. Over a 6-hr period after intake of a standard meal, the percentage of energy derived from carbohydrate, fat, and protein oxidation was relatively constant at 70, 24, and 6, respectively. With postabsorptive dogs, the percentages of energy derived from carbohydrate, fat, and protein were significantly different ( P <.01) and in the ratio of 45:53:2. Urinary nitrogen, amino acids, 17-hydroxycorticosteroids, Na, and K were examined in postabsorptive animals at rest and at work. Over a 3-hr period, the urinary NPN and Na were 0.49 g and 5.8 mEq, respectively, and unaffected by work; K and hydroxycorticosteroids were 4.6 mEq and 228 μg, respectively, and significantly elevated during work. Of 18 amino acids measured, only cystathionine excretion was significantly altered during work. In running trials of 88–600 min duration, both NPN and 17-hydroxycorticosteroids showed a tendency to increase with calorie expenditure. Submitted on December 22, 1961
Characteristics of an inspiration-augmenting reflex in anesthetized cats
Authors: Reynolds Leslie B. 
Published: December 2017

Overinflation or release from deflation of the lungs in anesthetized cats induced a vagally mediated, inspiration-augmenting reflex, characterized by a sudden phrenic motor discharge and an increase in rate and depth of inspiration. It resulted in an increase in end-expiratory volume and lung compliance. In a series of sinusoidal inflations, the reflex could exhibit summation to occur on any single inflation, but having occurred, was temporarily refractory to further inflations. The spontaneous deep breath was shown to be the same reflex, being vagally mediated, and similarly related to changes in mechanical properties of the lungs. The effective stimulus was shown to be a function of velocity and duration of inflation, while the refractoriness shown by the reflex was related to the accompanying increase in end-expiratory volume. The inspiration-augmenting reflex, by increasing functional residual capacity and compliance, was presumed to open alveolar units. It may interact with the Hering-Breuer inspiration-limiting reflex in controlling the respiratory cycle. Submitted on January 8, 1962
Epileptogenic effects of pure metals implanted in motor cortex of monkeys
Authors: Chusid Joseph G. , Kopeloff Lenore M. 
Published: December 2017

The ability of pellets of 26 pure metals to induce clinical epilepsy was evaluated in chronic experiments in 40 monkeys after precentral motor cortical implantation. Nickel and antimony were most effective. A variable mild epileptogenic effect was noted with bismuth, cadmium, zirconium, tin, titanium, iron, molybdenum, mercury, vanadium, tungsten, and tantalum. Other metals, including lead, beryllium, silicon, copper, silver, chromium, cobalt, manganese, zinc, and magnesium were ineffective. Most metal implants were associated with local meningocerebral cicatrix formation, but with five metals (nickel, copper, mercury, antimony, and cadmium) a profound, severe, necrotizing foreign-body reaction occurred. Clinical evidence of toxicity attributable to the metal implants was noted in monkeys treated with nickel, antimony, cadmium, and thallium. Submitted on February 7, 1962
Effects of dietary protein on physical work capacity during severe cold stress
Authors: Rodahl K. , Horvath S. M. , Birkhead N. C. , Issekutz B. 
Published: December 2017

The effect of four different diets ( I: 3,000 kcal, 70 g protein; II: 3,000 kcal, 4 g protein; III: 1,500 kcal, 70 g protein; IV: 1,500 kcal, 4 g protein) on physical work capacity (treadmill running at 7.5 mph and 8.6% grade) was studied in normal young men at ambient temperatures of 22 and 8 C. In 9 days at 22 C there was no difference between the diets with respect to performance capacity. At 8 C no significant deterioration in physical work capacity was observed in nude subjects living on diet I for 9 days, but a marked deterioration occurred after 5 days on diet IV. A significant deterioration also occurred on diet II, as well as on diet III. It is thus evident that a marked reduction in calories or in protein causes deterioration in physical work capacity in men exposed to severe cold stress. In the cold, resting metabolism of men on all diets increased about twofold, resting pulse rate increased by about 20–30 beats/min on an average, and the pulse rate at submaximal work load was similarly increased. There was a significant increase in the urinary excretion of catecholamines in the cold. Submitted on February 9, 1962
Pulmonary clearance of inert gases with particular reference to ethyl ether
Authors: Noehren Theodore H. 
Published: December 2017

Theoretical approaches to inert gas exchange in the lungs have indicated that ventilation, perfusion, and the solubility of the gas (blood-air distribution at equilibrium) are the determining factors in gas elimination by expired air. A mathematical expression is derived to predict clearance of inert gases based on these three factors: Qcl.x = V a.o2Q/(Va.o2 + SxQ). The derivation of this equation is supported by empirical data using ethyl ether in dogs to indicate that the dead space for ether and oxygen are substantially the same under the conditions of this study, and that there is complete equilibration between the ether concentration in arterial blood and end-tidal, “alveolar,” air. The solubility of diethyl ether in blood is high enough that, according to this equation, its pulmonary clearance should be governed by ventilation and substantially independent of cardiac output within ordinary ranges of these two factors. As such, its use as a measure of effective alveolar ventilation in a variety of laboratory and clinical situations is suggested. Submitted on January 22, 1962
Differences between deep pain responses to hypertonic and hypotonic saline solutions
Authors: Jarvik Murray E. , Wolff B. Berthold 
Published: December 2017

Different concentrations of both hypertonic and hypotonic aqueous sodium chloride solutions (0.2 ml) were injected into 24 hypodermic needles inserted in the gluteus medius muscles of 12 human subjects. It was found that a) both duration and intensity of deep pain responses were related to sodium chloride concentration; b) both latency and duration of pain responses were significantly greater with hypertonic than with hypotonic saline solutions; and c) hypertonic saline tended to induce subjective reports of a diffuse, dull ache, whereas hypotonic saline produced descriptions of a sharp, pricking, and well-localized pain. Submitted on April 3, 1962
Threshold Pco2 dependence on arterial pH for the respiratory system of dogs
Authors: Honda Yoshiyuki , Hasumura Nariko , Natsui Teijiro , Nakamura Keiko 
Published: December 2017

By observing respiratory discharges of the phrenic nerve, the threshold values of Pco2 (Ptco2) as chemical stimulus for the respiratory system were examined at varying arterial pH's on anesthetized dogs with and without vagotomy. 1) The reliability of the Ptco2 obtained by this method was high, the standard deviation being 0.48 mm Hg of Pco2. 2) The Ptco2 was lowered as the arterial cH (Ht) was increased by ammonium chloride infusion. The relationship between the Ptco2 and the Ht was linear and the regression line was calculated to be Ptco2 + 0.429 Ht = 44.0 for vagotomized and Ptco2 + 0.361 Ht = 46.1 for nonvagotomized dogs. 3) By combining this equation with that previously obtained expressing the partial effect of increased arterial cH and Pco2 on alveolar ventilation ratio (VR), the general chemical stimulation equation for ventilation in anesthetized normal dogs was derived to be VR = 0.194 Pco2 + 0.071 H – 8.94. 4) The Ptco2 of vagotomized dogs was several millimeters Hg lower than that of nonvagotomized dogs. Submitted on April 23, 1962
Effect of forward acceleration and negative pressure breathing on pulmonary diffusion
Authors: Zechman Fred , Mueller Gustave 
Published: December 2017

Forward acceleration decreases lung volumes, resembling negative pressure breathing (NPB). At 4 g the relaxation pressure curve is shifted downward and to the right 15 mm Hg. Pulmonary gas exchange and diffusion capacity were measured in nine human subjects during NPB (-15 mm Hg) and forward acceleration (4 g). Pulmonary ventilation increased approximately 40% in each condition. The O2 uptake increased with NPB (from 261 to 293 ml/min) and was slightly decreased or unchanged at 4 g. Carbon dioxide elimination increased in both experimental conditions. The apparent steady-state Dco was unchanged by NPB but decreased from an average control value of 21 to 12 ml/min mm Hg at 4 g. Since lung volumes are decreased by comparable amounts in both conditions, it is believed that the deleterious effects observed with forward acceleration are associated with the increased hydrostatic gradient from chest to back. Note: (With the Technical Assistance of Justin Taylor) Submitted on June 4, 1962
Effects of anemia and hemorrhagic shock on pulmonary diffusion in the dog lung
Authors: Burrows Benjamin , Niden Albert H. 
Published: December 2017

Hemorrhagic shock induced a marked fall in the pulmonary diffusing capacity for carbon monoxide in the dog (Dl) and produced marked nonuniformity of Dl/Va ratios throughout the lung as assessed by the “equilibration technique”. Difficulties in calculating over-all Dl under these conditions are discussed. Induced anemia also produced a fall in Dl, but little change in the uniformity of Dl/Va ratios was noted. In isolated perfused dog lungs where blood flow, pulmonary vascular pressures, lung volume, and ventilation were maintained constant, Dl was found to be proportional to hematocrit, suggesting either: 1) that virtually all resistance to CO diffusion is in the erythrocyte or 2) that the apparent diffusing capacity of the alveolar-capillary membrane is dependent upon hematocrit, carbon monoxide transfer being reduced across portions of membrane which are some distance from a red blood cell. Submitted on January 12, 1962
Central and peripheral factors in dynamic thermoregulation
Authors: Randall W. C. , Rawson R. O. , McCook R. D. , Peiss C. N. 
Published: December 2017

Direct measurements reveal that hypothalamic temperature is significantly higher than that of the tympanic membrane of the cat under Sernyl anesthesia. The posterior hypothalamus is warmer than the anterior hypothalamus. Bilateral carotid occlusion results in prompt elevation in both anterior and posterior hypothalamic temperatures while the tympanic membrane simultaneously cools. Thus, the hypothalamus is normally cooled by its arterial blood supply while the tympanic membrane is warmed by it. The marked differences in relative temperatures, together with opposite temperature changes imposed by arterial occlusion, underline the danger of assuming identity in temperature of these areas under dynamic conditions. The elicitation of sweating in man by a strong heat stimulus applied to occluded extremities strongly supports the hypothesis that cutaneous thermal receptors participate. The merging of a hot sensation into one of severe pain strongly suggests the participation of the C-fiber system of cutaneous afferents in the response. It is concluded that sweating may be elicited by 1) a primary stimulus arising within the thermal receptors of the anterior hypothalamus, 2) stimulation of cutaneous thermal receptors, or 3) some combination of the two. Submitted on June 22, 1962
Balance of blood flow and gas exchange during partial heart-lung bypass
Authors: Hopf Max A. , Galletti Pierre M. 
Published: December 2017

During partial heart-lung bypass, O2 uptake and CO2 elimination occur simultaneously at two sites: in the natural lung and in an artificial gas-exchange device. The total amount of arterialized blood distributed to the body tissues is the sum of pulmonary blood flow plus extracorporeal flow. When the extracorporeal flow rate is increased, the pulmonary blood flow decreases in proportion, provided the body blood content remains constant. Therefore, the total tissue perfusion during partial heart-lung bypass is not significantly different from the control value. The decrease in pulmonary blood flow is accompanied by a less marked decrease in pulmonary ventilation and gas exchange. Partial heart-lung bypass permits diminishing the pulmonary blood flow while maintaining normal metabolic conditions for the organism. Submitted on July 24, 1961
A comparison of static volume-pressure relations of excised pulmonary lobes of dogs
Authors: Frank N. R. 
Published: December 2017

Comparison was made of essentially static volume-pressure relations of the lobes of excised dogs' lungs during stepwise deflation from a maximal distending pressure of 30 cm H2O. No systematic differences were found among the right apical, middle, and left apical lobes nor between the right and left lungs when gas volume was expressed per unit of tissue weight. However, the right mediastinal-lower and left lower lobes held smaller volumes for any pressure than did the others. The differences were small and appear to play a subordinate role in causing the uneven ventilation typical of healthy lungs. These observations relate only to elastic variations among lobes and are not intended to characterize variations that may exist within lobes. Note: (With the Technical Assistance of Eleanor Root) Submitted on August 13, 1962
Transient responses to CO2 breathing of human subjects awake and asleep
Authors: Fuleihan F. J. D. , Nakada T. , Suero J. T. , Merrifield E. S. , Dutton R. E. , Permutt S. , Riley R. L. 
Published: December 2017

Ventilation and end-tidal Pco2 were studied in six subjects awake and asleep (following the ingestion of 200–300 mg sodium pentobarbital) during oxygen breathing and the administration and withdrawal of 4% CO2 in oxygen. During the control period as well as steady-state CO2 breathing, ventilation was significantly lower in asleep than in awake subjects. There was no significant difference between sleep and wakefulness in end-tidal Pco2 or in the slope of the ventilatory response to 4% CO2. The transient responses of ventilation and end-tidal Pco2 of the group as a whole were similar in sleep and wakefulness. Ventilation changed more slowly than did end-tidal Pco2. End-tidal Pco2 overshot beyond the steady-state CO2 breathing value at the onset of CO2 breathing; and undershot below the control value during recovery. The magnitudes of both the overshoot and undershoot of end-tidal Pco2 were correlated significantly to the slope of the ventilatory response to 4% CO2, in the whole group awake and asleep. Submitted on October 4, 1962
Effect of CO2 on hyperventilation produced by vibration
Authors: Young W. A. , Shaw D. B. , Buckles L. J. , Outerbridge J. S. , Reeves C. E. , Truman J. C. 
Published: December 2017

Twenty-five normal subjects were exposed to low-frequency high-amplitude passive vibratory movements of the body. Hyperventilation and hypocapnia resulted in most cases. Restoration of the alveolar Pco2 to its resting value by the addition of CO2 to the inspired air while vibration continued gave rise to no further increase in ventilation. It is concluded that the hyperventilation produced by vibration is not moderated by the resulting fall in arterial Pco2. Thus, observed differences between the ventilatory response of different individuals to vibration are unlikely to be due to differences in sensitivity to CO2. Several other studies have demonstrated a threshold level of alveolar CO2 below which respiration is not stimulated by CO2. The lack of response to CO2 in the present experiments may be due to the fact that they have been carried out at levels of alveolar CO2 below this threshold Submitted on September 21, 1962
Circulatory and ventilatory effects of exercise in smokers and nonsmokers
Authors: Chevalier Robert B. , Bowers John A. , Bondurant Stuart , Ross Joseph C. 
Published: December 2017

To evaluate the effects of cigarette smoking on some of the circulatory and ventilatory responses to exercise, a group of young male subjects, 18 smokers and 14 nonsmokers, was studied. Exercise consisted of a standard 5-min bicycle ergometer test that achieved a mean O2 uptake of 1.44 liters/ min in the 5th min of exercise. There was no difference between smokers and nonsmokers in the O2 uptake achieved during subsequent maximal exercise. Pulmonary function studies performed on the two groups revealed normal results for each group. There was an oxygen debt accumulation among smokers that was significantly greater ( P < 0.001) and this debt represented a greater per cent of the total O2 uptake. The heart rate at rest and 3 min after exercise in smokers was significantly faster ( P < 0.02). These differences do not appear to be related to ventilatory factors and may, therefore, be due to either circulatory or metabolic differences in the two groups. Submitted on August 17, 1962
Differences between ethnic groups in physical working capacity
Authors: Wyndham C. H. , Strydom N. B. , Morrison J. F. , Peter J. , Williams C. G. , Bredell G. A. G. , Joffe A. 
Published: December 2017

Maximum oxygen intake per kilogram body weight of Caucasian, Bantu, and Bushmen males in a similar state of physical training are not significantly different, being about 48 ml/min kg. This figure is similar to that of Robinson's Negro sharecroppers and to the U. S. Army recruits of Taylor et al. Very highly trained men, i.e., Åstrand's gymnasts and international class athletes, have higher values. Landy's is 76 ml/min kg. Sedentary existence reduces this figure to about 40 ml/min kg. Oxygen consumption plotted against work rate is significantly lower for Bantu men than for Caucasian; Bushmen are like the Bantu. Ventilation volume (BTPS) plotted against oxygen consumption is about 30 liters/ liter oxygen consumption at 6,000 ft altitude, compared with 20.6 liters for Åstrand's men at sea level. Submitted on July 1, 1962
Response to high pressure oxygen of conscious volunteers and patients
Authors: Foster C. A. , Churchill-Davidson I. 
Published: December 2017

A trial is described in which 19 fit volunteers and 49 patients with malignant tumors have breathed oxygen at a pressure of 3–4 atm abs for periods of from 21 to 67 min in a pressure chamber filled with oxygen. Subjects at complete rest will not safely tolerate 4 atm abs for frac12 hr but are unlikely to show signs of oxygen toxicity in a similar period at 3 atm abs. One patient convulsed during decompression after 46frac14 min at 3 atm pressure. A slow, even rate of pressurization did not prevent the occurrence of otitic barotrauma in nine of the volunteers. The patients had myringotomies performed. Temperature and pulse rate changes are described. Submitted on May 31, 1962
Volume-pressure relationships during pressure breathing and voluntary relaxation
Authors: Johnson Louis F. , Mead Jere 
Published: December 2017

Lung volumes during pressure breathing (PB) were measured in six subjects by two methods: 1) The subject was seated completely enclosed in a body plethysmograph breathing room air through a tube; pressures were applied to this tube and volume changes were recorded from the plethysmograph. 2) The subject was seated enclosed in a body box except for his head which protruded through a respirator collar; pressures were applied around the body and lung volume changes were recorded from a bag-box system. In addition, relaxation pressure (RP) measurements were obtained. Volume-pressure relationships by PB 1 closely approximated those by RP, whereas PB 2 tended to yield smaller volume changes for a given pressure than the other methods. The extrathoracic airways are subjected to the applied pressure in PB 1 and RP, but not in PB 2. The different results may relate to this difference. Submitted on June 14, 1962
Pulmonary mechanics and diffusing capacity following simulated space flight of 2 weeks duration
Authors: Dubois Arthur B. , Hyde Richard W. , Hendler Edwin 
Published: December 2017

Studies of pulmonary mechanics and diffusing capacity were carried out shortly after completion of exposure to the gas composition, barometric pressure, and acceleration profile simulating an earth orbital mission of 2 weeks duration. The values obtained for pulmonary function on the three subjects were normal. However, there still is a potential fire hazard in the atmosphere of 100% oxygen at frac13 atm. Submitted on January 28, 1963
Optical density changes in dog blood at full oxygen saturation with changes in pCO2
Authors: Salmon Peter , Stish Richard , Visscher Maurice B. 
Published: December 2017

Quantitative studies have been made of the changes in optical density of whole blood at two wavelengths at full oxygen saturation with changes in carbon dioxide tension and content. At both λ 630 mμ and λ 805 mμ there are lower densities with increasing pCO2 at full oxygen saturation. From pCO2 1.5 to 243 mm Hg the decrease is 0.133 OD units and is equal at the two wavelengths. The OD is linearly related to the pH change. The effect is ascribed to the differences in light scattering by erythrocytes with changing shape and/or volume of the cells. This effect results in a systematic error in measurements of oxygen content of blood when the carbon dioxide content varies, as it does between arterial and venous blood. Submitted on October 22, 1962
Relationship between skin temperature and performance in the Java monkey
Authors: Bush Robert D. , Rohles Frederick H. , Reynolds Herbert H. , Koestler Fred G. 
Published: December 2017

Four male Java monkeys ( Macaque iris), trained to perform a continuous avoidance task, were used in an exploratory study of diurnal skin-temperature changes and their relationship to avoidance behavior. Significant diurnal skin-temperature changes were detected, and a relationship between bar-pressing rate and skin temperature of the back was shown to exist. Submitted on December 6, 1962
Effect of vapor pressure on physiologic strain and body heat storage
Authors: Hall John F. 
Published: December 2017

Physiologic strain, in terms of body heat storage, and other physiologic responses were measured and compared in two series of heat stress experiments performed on human subjects exposed to different ambient vapor pressures. One group of 75 experiments conducted on 5 healthy nonacclimatized male subjects exposed 5 times each to 38, 54, and 71 C at 10 mm Hg vapor pressure was compared with a series of 81 experiments performed on 10 similar subjects exposed 1–6 times each to 38, 41, and 54 C at 20 mm Hg vapor pressure. Subjects were sitting and wore 1.0 clo insulation. The data show relation between body heat storage and a) the modified Craig index of physiologic strain; b) over-all sweat rate; c) evaporative rate; d) sweat-evaporative ratio; e) mean skin and rectal temperatures; and f) change of heart rate at the respective vapor pressure levels. Statistically significant correlation between sweat-evaporative ratio and over-all sweat rate with body heat storage is shown. Use of the over-all sweat response as a physiologic strain index is suggested. Submitted on August 14, 1962