bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of cooling of orbital cortex on exercise hyperpnea in the dog
Authors: Henry John P. , Whitehorn W. V. 
Published: December 2017

The significance of cortical contribution to the hyperpnea of exercise has long been debated. An attempt was made to evaluate the role of this factor by cooling the respiratory area of the orbital cortex in 20 experiments on 13 Nembutal-urethane anesthetized dogs before, during and after electrically induced exercise of the hind limbs. Orbital cooling during eupnea produced a 10% decrease in respiratory rate with questionable reduction of minute volume. Cooling induced during exercise resulted in reduction of mean ventilatory volume from 4.37 l/min. to 4.18 l/min. The difference is highly significant statistically and represents 20% of the exercise hyperpnea under these conditions. Cessation of cooling was followed by return to precooling levels. Results indicate that cortical impulses contribute to exercise hyperpnea even under conditions of anesthesia and low levels of exercise and suggest a quantitative approach to evaluation of this factor under more physiologic conditions. Submitted on July 21, 1958
Effectiveness of perphenazine and Systral against motion sickness
Authors: Milch Lawrence J. , Frankl Harold D. , Renzi A. A. 
Published: December 2017

Perphenazine, a drug with high activity against apomorphine-induced vomiting in dogs, and Systral, an antiemetic analogue of benadryl with little or no activity against apomorphine-induced vomiting in dogs, were tested for antimotion sickness activity in human beings aboard aircraft. Neither furnished any protection. Further, dogs were swing-tested after the administration of chlorpromazine and perphenazine. In spite of the significant difference in protection against apomorphine-induced vomiting afforded by the two drugs (perphenazine much greater than chlorpromazine), perphenazine failed to protect against swing-induced vomiting and chlorpromazine furnished only 25% protection. These data emphasize the unreliability of extending the results of apomorphine inhibition to the relationship of the chemoceptive trigger zone to motion sickness. Submitted on September 12, 1958
Electroencephalogram and sleep deprivation
Authors: Armington John C. , Mitnick Leonard L. 
Published: December 2017

The occipital alpha rhythm was recorded from 10 subjects before, during and after a 98-hour period of sleep deprivation. The alpha rhythm declined progressively and was nearly absent in most subjects after 50 hours of deprivation. At every stage of deprivation the alpha activity was smaller during counting as compared to adding numbers. Stimuli that normally produce alpha block were found to elicit alpha rhythm when the effects of deprivation were apparent. Following deprivation alpha recovered rapidly and within 24 hours was essentially normal. Submitted on July 23, 1958
Physiological effects of chronic exposure to carbon monoxide
Authors: Wilks Syrrel S. , Tomashefski Joseph F. , Clark Robert T. 
Published: December 2017

A group of seven dogs was given a daily 6–8 hour exposure to CO levels of 0.08 to 0.10% for a period of 36 weeks and their tolerance to CO was compared with that of normal dogs, altitude-acclimatized dogs and dogs transfused with blood from normal dogs. The observed increased tolerance to CO was attributed primarily to the increase in concentration of the hemoglobin pigments of the blood. With this increased hemoglobin there was a greater reserve of the pigment for O2 transport at a given concentration level of HbCO. The time required to reach an equilibrium level with a given Pco was greater for the acclimatized than for the normal animals. The PaOO2 was always lower than PaOO2 during the acclimatization period. There was no evidence of factors, other than hematologic, which increased the tolerance of the dogs to CO. Animals subjected to other hypoxic stress such as altitude, or normal animals transfused with normal blood to increase the hematocrit level, showed increased tolerance similar to that accomplished by chronic exposure to low CO levels. Submitted on September 22, 1958
Effects of pure carbon monoxide gas injection into the peritoneal cavity of dogs
Authors: Wilks Syrrel S. 
Published: December 2017

Relatively large quantities of pure carbon monoxide (500 ml) were injected into the peritoneal cavity of normal dogs, CO-acclimatized dogs and altitude-acclimatized dogs. Withdrawal and analysis of the gas at timed intervals revealed a rise in oxygen tension from zero to values which were 2frac12 times the PaOO2. The PiOO2 (intraperitoneal O2 tension) in the acclimatized dogs attained values significantly higher than for the normal dogs. The PiCOCO2 (intraperitoneal CO2 tension) in all dogs approximated the value in normal animals. At no time after the injection did the COHb exceed a 40–50% concentration level. The physiologic mechanism of the observed phenomena is discussed. Submitted on September 22, 1958
In vitro effect of nonindole compounds on oxidative activity of ceruloplasmin
Authors: Hanson K. M. , Austin D. C. , Aprison M. H. 
Published: December 2017

It has already been shown that, in addition to ascorbic acid, 5-hydroxytryptamine and several other 5-hydroxyindole compounds affect the oxidative activity of ceruloplasmin and serum oxidase. Therefore, an in vitro study of the effect of several other normal metabolites and drugs on this enzyme system was undertaken. It was found that the compounds which affect this reaction fall into two classes. One group (cysteine, penicillamine and ascorbic acid) reacts with the oxidized form of the substrate reducing it back into the original compound, thereby producing a lag period in the reaction. The other group (DOPA and iproniazid) inhibits the reaction, probably by competing with the substrate molecules for the enzyme site. Submitted on November 17, 1958
Effect of a vapor barrier on rates of excretion of sweat solutes
Authors: Bass David E. , Mager Milton , Barrueto Richard B. 
Published: December 2017

The effects of a vapor-impermeable barrier on rates of excretion of Na, Cl, K, true creatinine and ‘apparent’ creatinine from the arms of men during thermal sweating were determined by collecting sweat solutes simultaneously from both arms, one of which was enclosed in a polyethylene bag. The separate effects on rates of excretion of the higher local skin temperature (Ts) and relative humidity (RH) imposed by a vapor barrier were assessed by means of a thermoregulated arm-chamber. Wearing a vapor barrier resulted in a significantly decreased rate of excretion of K and an increased rate for both true and ‘apparent’ creatinine. The effect on ‘apparent’ creatinine was attributable entirely to the increased excretion of the fraction represented by true creatinine. Rates of excretion of Na and Cl were not significantly affected by the vapor barrier. Increased Ts, per se, resulted in higher excretion rates of Na, Cl, K, true creatinine and urea. Increased RH, per se, led to decreased excretion of Na, Cl, K and urea, but no effect on rate of excretion of true creatinine. The observed effect of a vapor barrier on excretion rates of these sweat solutes was therefore the net result of Ts and RH operating in opposite directions. Submitted on July 31, 1958
Influence of age on pulmonary diffusing capacity
Authors: Donevan R. E. , Palmer W. H. , Varvis C. J. , Bates D. V. 
Published: December 2017

The pulmonary function of 24 normal subjects ranging in age from 20 to 50 years has been studied at rest and during exercise. At rest there is a significant decrease with age in the pulmonary diffusing capacity and the level of diffusing capacity attained on exercise at any particular oxygen uptake decreases with increasing age. Simultaneous measurements of O2 uptake, ventilation, end tidal O2 and CO2 concentration and calculated alveolar CO2 concentration, using the Bohr equation, show no evidence that any of these measurements are significantly influenced by age. The predicted maximal O2 diffusing capacity ( J. Appl. Physiol. 6: 588, 1954) predicts with fair accuracy the diffusing capacity for carbon monoxide that will be found in any given individual at an O2 uptake of about 2.8 l/min. It correctly predicts the change in CO diffusing capacity with increasing age. Reasons are given for suggesting that the decrease in pulmonary diffusing capacity observed may be explained by a diminution in cardiac output with increasing age. Submitted on November 21, 1958
Possible errors using esophageal balloon in determination of pressure-volume characteristics of the lung and thoracic cage
Authors: Knowles John H. , Hong Suk Ki , Rahn Hermann 
Published: December 2017

The static pressure-volume curves of the lung, thoracic cage and total respiratory system were studied in the sitting, supine, prone and knee-elbow position in four subjects. The lung and thoracic-cage pressures were measured with the aid of an esophageal balloon and recorded on a water manometer. The analysis of these various components suggests that in the supine position the esophageal balloon is compressed by the mediastinal content, giving rise to an artifact in the recording of the lung pressure. If this artifact is taken into consideration, it would appear that the effect of posture on the compliance of the lung is negligible. Lung pressures calculated for various lung volumes during active breathing are compared with static values recorded on a water manometer. Submitted on December 19, 1958
Summation and tetanus in postmortem human heart muscle
Authors: Ullrick William C. , Lentini Eugene A. , Sommers Sheldon C. 
Published: December 2017

Induced isometric contractions were recorded from trabeculae carneae from the left ventricles of human hearts obtained at autopsy. Increasing the frequency of stimulation from a driving rate of 1/sec. up to 10/sec. resulted in complete tetanic contractions in the majority of experiments. The tetanic response was usually coupled with summation. The occurrence or nonoccurrence of tetanus was correlated with the contraction time-refractory period ratios. Submitted on December 16, 1958
Thermal and metabolic responses of the Australian aborigine exposed to moderate cold in summer
Authors: Hammel H. T. , Elsner R. W. , Le Messurier D. H. , Andersen H. T. , Milan F. A. 
Published: December 2017

Measurements of thermal and metabolic responses of central Australian aborigines exposed to moderate cold during sleep were repeated during summer and have shown that the small, but important, differences between these natives and control whites exist in summer to the same extent as in winter. The metabolism of the central natives declined continually throughout the night with a Q10 of about two in summer as in winter. Without metabolic compensation, body temperatures of the central natives fell at a greater rate than those of the whites. Measurements of thermal and metabolic responses of a mixed tribal group of tropical Australian aborigines under identical conditions of cold exposure have shown that the average tropical native was intermediate between central natives and control whites. The metabolic rate for tropical natives was 42.8 Cal/m2/hr. compared with 48.7 Cal/m2/hr. for whites and 37.0 Cal/m2/hr. for central natives. We suggest that the Australian aborigine has an inborn ability to tolerate greater body cooling without metabolic compensation which can be increased by prolonged exposure to cold. Submitted on December 3, 1958
Comparative features of the mechanics of breathing
Authors: Agostoni Emilio , Thimm Frederick F. , Fenn W. O. 
Published: December 2017

Dogs, cats, rabbits, guinea pigs and rats have been studied. The lung-thorax compliance per unit body weight and per unit vital capacity shows some significant differences between species. Static pressure required by a normal inspiration is, however, similar in different animals. The expiratory reserve per unit vital capacity and the functional residual capacity per unit total lung capacity are larger in the animals breathing at lower frequency. These findings are related to the hypothesis that animals breathing at lower frequency have a larger functional residual capacity in order to contain within small limits the changes in composition of the alveolar air due to the breathing cycle. Relationship between dynamic pressure and flow follows Rohrer's equation. The dynamic pressure required by a normal ventilation is similar in the different species. Relationship between rate of work of breathing and breathing frequency shows that the frequency typical of each animal is that corresponding to the minimum rate of work. Submitted on April 13, 1959
Breath-by-breath sampling of end-expiratory gas
Authors: Lambertsen C. J. , Benjamin J. M. 
Published: December 2017

An electromechanical method is described for breath-by-breath sampling of gas from the respiratory passages of experimental subjects or from various locations in the breathing apparatus employed. The sampling system includes features permitting the initiation of sampling at different phases of exhalation, initiation of sampling by inspiration and the varying of sampling duration. The breath-by-breath sampling system is shown to be adaptable to physiological and pharmacological studies of spontaneous fluctuations in the composition of end-tidal gas, studies of the rate of change of end-expiratory gas in transitional states and to artificial control of end-tidal pCO2. The magnitude of the pCO2 difference between end-tidal gas and arterial blood is shown to decrease to essentially zero as tidal volume is increased above normal levels. Submitted on February 11, 1959
Respiratory effects of a calibrated volume-limited pressure-variable ventilator during surgery
Authors: Etsten Benjamin , Reynolds Robert N. , Li T. H. 
Published: December 2017

The application of a calibrated volume-limited, pressure-variable ventilator was studied in 34 patients during surgery. Tidal volume and respiratory frequency were determined by means of the Radford nomogram and ventilation was controlled throughout the intra-abdominal and intrathoracic procedures. There was no resistance to the expiratory flow of gases and the recoil of the lung was not impeded during the expiratory phase. The tidal volume was unchanged while the airway pressure varied in relationship to the change of the nonelastic and elastic resistance of the lung-thorax system. The ratio of the duration of the expiratory flow of gas to the duration of the expiratory pause varied in accordance with the changes of the airway resistance and was not altered by the ventilator. This allowed a sufficient duration of the pause period for compensatory circulatory adjustment. Adequate alveolar ventilation was maintained during surgery from 1–6 hours as indicated by the level of the arterial pCO2 (range: 30–48 mm Hg). Submitted on October 20, 1958
Effect of bronchial and arterial constriction on alveolar gas concentrations in a lobe of the dog's lung
Authors: West J. B. , Hugh-Jones P. 
Published: December 2017

Gas concentration tracings were obtained with a mass spectrometer by sampling in the left lower lobe bronchus of open-chested dogs ventilated by a plethysmograph. Partial bronchial obstruction and/or arterial obstruction could be produced by tightening clamps on the bronchus and the branch of the pulmonary artery supplying the lobe. Characteristic patterns of oxygen, carbon dioxide and argon concentration (following a single inspiration of an argon-air mixture) were found with partial bronchial obstruction, arterial obstruction and a combination of both. The patterns were explained by alterations in the ventilation-perfusion ratio and in the phase of ventilation of the obstructed lobe. By relating the tracing taken during mixed obstruction to the pressure cycle of the plethysmograph, some mechanical properties of the obstructed lobe were derived. Submitted on September 3, 1958
Patterns of gas flow in the upper bronchial tree
Authors: West J. B. , Hugh-Jones P. 
Published: December 2017

Patterns of gas flow in the upper bronchial tree have been studied by observing the flow of dye and different gases through a lung cast, and by measurements made on open-chested dogs and on human beings at bronchoscopy. Flow is completely laminar throughout the bronchial tree at low expiratory flow rates (up to 10 l/min.) and completely turbulent, proximal to the segmental bronchi, at high flow rates (80 l/min.). Both at low and high expiratory flow rates, gas from segmental bronchi was not uniformly mixed in the lobar or main bronchi which they supplied. The composition of a catheter sample in these airways would therefore not be representative of the alveolar gas in the corresponding lobe or lung unless the alveolar gas in all areas distal to the sampling tube was homogeneous. Penetration of the left upper lobe bronchus by gas from the lower lobe was demonstrated in the model and a normal subject at bronchoscopy. Submitted on September 3, 1958
Effects of heat and cold on the albino rat: crossed resistance or crossed sensitization?
Authors: Fleischner Jerry Robert , Sargent Frederick 
Published: December 2017

Two experiments were carried out to test whether or not cold-acclimatized rats adjust better to heat and heat-acclimatized rats adjust better to cold than rats not previously exposed to either environmental extreme. In both, groups of rats were exposed to 94.5°–96.5℉ (hot), 33°–40℉ (cold) and 76°–78℉ (control). In the first experiment 45 female Holtzman littermates were used. After 50 days, ‘hot’ rats were abruptly transferred to cold, ‘cold’ rats to heat. Control animals were also placed in each environment. In the second experiment 55 identical rats were similarly treated; the cross, however, was made after 29 days. Rats exposed to 95℉ exhibited sustained hypothermia. Rats exposed to 36℉ developed a transient hypothermia which lasted longer in the first experiment than in the second and was accompanied by more severe cold injury. Heat was not a stress in the sense of Selye, but cold was. There was crossed sensitization rather than crossed resistance. Submitted on January 26, 1959
Mammary ketogenesis in the cow
Authors: Kronfeld D. S. , Kleiber Max 
Published: December 2017

Acetate–2–C14 was injected intracisternally into one quarter of the udder of a normal and of a mildly ketotic cow. The standardized specific activities of fat and ketone bodies in the milk sampled from the injected quarter were greater than those from the noninjected quarter. The percentage of direct udder transfer of C14 was calculated for the normal and ketotic cow, respectively, as 92% and 83% for milk fat, 72% and 94% for beta-hydroxy-butyrate and 80% and 98% for the acetone plus acetoacetate fraction. Total–C14 recovery was decreased in the milk fat, but increased in the milk ketone bodies during ketosis. The results indicated that mammary ketogenesis from acetate occurs in cows and suggested that it is increased during bovine ketosis, probably in association with impaired mammary lipogenesis from acetate. The possible role of coenzymes in bovine ketosis is discussed. Submitted on June 25, 1959
24-Hour rhythm in susceptibility of C mice to a toxic dose of ethanol
Authors: Haus Erhard , Halberg Franz 
Published: December 2017

Male C mice were injected (i.p.) with 0.8 cc of saline or with a 25% ethanol solution in two experiments. In each experiment, separate subgroups of comparable mice were injected at 4-hour intervals during a 24-hour period, under conditions standardized for periodicity analysis. Death rates from ethanol showed a 24-hour rhythm in susceptibility; over 50% of the mice injected in one phase of rhythm died from the injection of a dose of ethanol which barely killed 30% of comparable mice injected in another phase, 12 hours earlier or 12 hours later. In one experiment, ethanol-induced hypothermia was recorded and its degree also was found to be a function of 24-hour rhythm. Submitted on January 6, 1959
Rate of fall of O2 tension in a lobe of dog lung after bronchial occlusion
Authors: West J. B. , Hugh-Jones P. 
Published: December 2017

The oxygen tension in a lobe of the dog's lung following occlusion of the bronchus was measured with a mass spectrometer. The bronchus was rapidly blocked by inflating a small latex balloon just proximal to the tip of the mass spectrometer sampling tube sited in the bronchus. Cannulas in the branch of the pulmonary artery allowed the blood flow to the lobe to be continuously monitored on a rotameter, and direct measurements of flow were made by collection of timed samples. The rate of fall of O2 tension following occlusion was approximately linear initially, and the rate correlated well with the direct measurement of perfusion when the animal was in a steady state. Preliminary trials suggest that the method can be used to compare lobar or segmental perfusion in different parts of the lung in man at bronchoscopy. Submitted on June 10, 1959
Various degrees of hypothermia in mice
Authors: Blumer W. F. C. , Cole J. 
Published: December 2017

Some mice were cooled to a deep body temperature of 15°C, others in ice for an additional 20 minutes to 1°C, still others in ice for 45 minutes to 1°C. The first group showed no impairment on a test for CNS function; the second produced equivocal results; in the third, transitory impairment occurred in skilled mice and in others, slowness in acquiring skill. This third group also showed decrease in weight gain and a mortality rate, especially among the heavier animals. It is inferred that duration as well as intensity of hypothermia is significant, and that a critical point is reached after 20 minutes in ice. Histology revealed no CNS damage. Submitted on October 27, 1958
Seasonal variation in human amino acid excretion
Authors: Hale Henry B. , Ellis James P. , Van Fossan Donald D. 
Published: December 2017

Amino acid excretion was studied in young, healthy men during summer, fall and winter months in a southwestern U. S. location. Both untimed and timed urine samples were employed. The amino acids determined were alanine, arginine, cysteine, glutamic acid, glutamine, glycine, histidine, lysine, methyl histidine, serine, threonine and valine. Supplemental determinations included urine volume, creatinine, uric acid, urea, sodium and potassium. Using untimed urine samples and expressing values as ratios with creatinine, significant seasonal variation was found for alanine, arginine, cysteine, glutamic acid, glycine, lysine and serine. Submitted on April 11, 1959
Role of pH and thrombin in the PNH hemolytic system
Authors: Auditore Joseph V. , Hartmann Robert C. , Flexner John M. 
Published: December 2017

The effect of bovine thrombin on pH-hemolysis curves in paroxysmal nocturnal hemoglobinuria (PNH) was studied. Symmetrical curves demonstrating accentuation of PNH hemolysis by thrombin were obtained. There was no skew toward relative increase in hemolysis at somewhat higher pH values such as might have been anticipated if the mechanism of the thrombin effect was mediated through heterophil antibodies. The buffering effect of small amounts of normal or PNH erythrocytes on acidified serum was studied. The present studies provide no evidence for impaired buffering capacity on the part of the PNH erythrocyte. One of the four PNH patients demonstrated no effect of thrombin on pH-hemolysis curves when autologous cell-serum suspensions were used. However, mixtures of compatible isologous normal or PNH serum with the cells of this patient did demonstrate potentiation of hemolysis when thrombin was added. Submitted on July 20, 1959