bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anticoagulant effects of concentrated cephalin in the thromboplastin generation test
Authors: Coffield Kenneth J. , Cocanour Mary Ann 
Published: December 2017

Concentrated suspensions of phospholipid (cephalin) inhibit thromboplastin generation as a result of adsorption or inactivation of factors V and VIII by the phospholipid. Such inhibition can be overcome by increasing the concentration of plasma and serum reagents, or allowing product I to form prior to the addition of phospholipid. Adsorption of plasma reagents with washed sedimented cephalin demonstrates directly the depletion of factors V and VIII. Submitted on July 5, 1962
Different effects of hypothermia on two syndromes of positive acceleration
Authors: Stiehm E. R. 
Published: December 2017

The tolerance to high positive (headward) acceleration at levels of 20–80 G was studied in normal and hypothermic rats. Normal rats have a mean survival time of 680 sec at 20 G, but this decreases to 105 sec at 30 G. Only slight decreases are noted at higher G, suggesting that 30 G is the point at which cerebral circulation is interrupted. Hypothermia at 22.5 C decreases acceleration tolerance at 20 G, but markedly increases acceleration tolerance at 30 G and above. At 40 G this effect is maximal, and the mean survival time for hypothermic rats is 252 sec, compared to 75 sec for controls, an increase of 236%. These different effects of hypothermia on acceleration tolerance suggest that there are two distinct syndromes of physiologic failure during positive acceleration. One is a “cardiac” syndrome, occurring at 20 G and below, characterized by partial maintenance of cerebral circulation until cardiac failure ensues, and the other is a “cerebral” syndrome, occurring at 30 G and above, characterized by immediate interruption of cerebral circulation and respiratory paralysis. Submitted on May 17, 1962
Alveolar gas exchange during breath-hold diving
Authors: Lanphier E. H. , Rahn H. 
Published: December 2017

Use of a recompression chamber permitted simulation of breath-hold dives to 33 ft of sea water (2 atm abs). Four normal subjects made such dives during rest and mild exertion while delivering alveolar gas samples at frequent intervals by a partial-rebreathing procedure. The course of alveolar gas exchange differed greatly from that in ordinary breath holding. Oxygen uptake remained at near normal levels until ascent owing to the maintenance of alveolar Po2 by increased ambient pressure. Reversal of CO2 transfer occurred during descent, and little CO2 moved in the normal direction until ascent. Greater uptake of oxygen and retention of CO2 in the body led to lower final values of both alveolar Po2 and Pco2 than in comparable breath holding at the surface. Hyperventilation made possible longer dives with harder work, and in these the Po2 reached very low values on ascent. One subject showed a final Po2 of 24 mm Hg with evidence of reversed O2 transfer. Acute hypoxia on ascent is a likely cause of drowning in breath-hold diving. Submitted on October 17, 1962
Partial marrow shielding and total-body irradiation
Authors: Noyes W. D. , Finch C. A. , Wasserman H. , Glickman K. 
Published: December 2017

The effects of shielding one femur on bone marrow morphology and function were studied in rats receiving total-body irradiation. Animals were exposed to 550 r from a Co60 source. Shielding consisted of 100 mm of lead, reducing exposure to one femur to 16 r. Marrow cell counts, radioiron localization in femurs, plasma iron turnover, red cell radioiron utilization, and peripheral cell counts were observed. Phlebotomy in some animals served as a functional stress. There was no observed morphological change in shielded marrow despite marked depopulation of nucleated cells in heavily irradiated marrow. In phlebotomized shielded animals, the rate of hemoglobin synthesis was nearly half that of unirradiated controls although retarded by several days whereas in unshielded animals, hemoglobin synthesis was further delayed and less than a third of control values. Initially the erythropoietic function resides primarily in shielded marrow as evidenced by radioiron localization and marrow cell counts with no evidence of indirect depression. Cellular repopulation appears more rapidly in partially shielded animals and compares favorably with the effectiveness of marrow transfusion. Submitted on December 5, 1962
Reflex effects of lung inflation on tracheal volume
Authors: Widdicombe J. G. , Nadel J. A. 
Published: December 2017

Transient lung inflation increased the volume of a bypassed tracheal segment in anesthetized dogs, whether spontaneously breathing or paralyzed and artificially ventilated. The degree of dilation during inflation varied with the state of “tone” of the tracheal muscle and with the inflation volume. Pulmonary denervation caused maintained constriction of the trachea and blocked the dilation during lung inflation. Cooling the cervical vagus nerves to between 7 and 12 C had the same effect. Both of these procedures blocked the Hering-Breuer inflation reflex, but the trachea still constricted following carotid body chemoreceptor stimulation by KCN. In paralyzed dogs, injection of veratrine into the right heart caused tracheal dilation, presumably by stimulating pulmonary stretch receptors. Left heart injection dilated the trachea much less. The former effect was abolished by pulmonary denervation. In anesthetized spontaneously breathing dogs carotid body chemoreceptor stimulation by KCN constricted the trachea; this was followed by increased ventilation and secondary tracheal dilation. Pulmonary denervation or muscular paralysis and artificial ventilation prevented the secondary dilation. These results establish the reflex nature of tracheal dilation during transient lung inflation and suggest that Hering-Breuer stretch receptors are the responsible end organs. Submitted on January 15, 1963
Effect of environmental temperatures on retention of cesium 137 by mice
Authors: Furchner J. E. , Richmond C. R. 
Published: December 2017

Three groups of 12 mice each were maintained at environmental temperatures of 34, 22, and 5 C for a period of about 7 weeks after an intraperitoneal injection of Cs137. Periodic assay of the activity in the whole body and excreta showed that as environmental temperature decreases the excretion of Cs137 increases, probably as a result of the increased metabolic rates associated with low temperatures. Submitted on November 19, 1962
Specific heat of canine blood
Authors: Epstein Wolfgang , Visscher Maurice B. , Stish Richard , Ballin Henry 
Published: December 2017

The relationship of specific heat of canine blood to hematocrit and density was determined at 37.46 C. Density is seen to give the better index of this property. The equation describing the relationship is: specific heat = 0.998 – 2.30 (specific gravity – 1). Submitted on October 6, 1961
Use of an electromagnetic flowmeter for urine flow measurements
Authors: Cardus D. , Quesada E. M. , Scott F. B. 
Published: December 2017

The measurement of instantaneous urinary flow has been a technical problem in studies of the dynamics of the urinary bladder. In this investigation, the adaptation of an electromagnetic flowmeter has proved to be useful in measuring the instantaneous flow of urine. The probe of this instrument was either connected directly to the subject by means of an adapter or it was placed in series with a funnel system which did not require contiguity with the subject. It is concluded that both the direct and the funnel procedures are suitable for the monitoring of instantaneous urine flow, the latter being particularly practical in the determination of peak flows during micturition. Submitted on September 5, 1962
Learning in hypothermic rats
Authors: Panuska J. A. , Popovic Vojin 
Published: December 2017

Inexperienced shaved adult white rats cooled to a colonic temperature of 18.5 C and then rewarmed to 26.0 C, were placed at an ambient temperature of 2.0 C with the possibility of using a lever-activated heat reinforcement apparatus. Their body temperatures leveled at 29 C; and during the next 40–80 min the rats either learned to press the lever systematically for external heat and thereby rewarmed themselves to euthermia, or they drifted into deeper hypothermia leading to death. Activity records and visual observations indicate that after an average of 48 min and at a body temperature of 29.6 C (28.5–30.2 C), out of a group of 14 rats 12 learned this technique necessary for their survival. All 12 rats reached euthermia and continued to use the lever as long as they remained in the experimental situation. It is concluded that learning is possible even at a low body temperature of 29.6 C. performance; heat reinforcement; temperature regulation; body temperature; environmental temperature; operant behavior; survival studies; motivation; physiology of learning; cold physiology Submitted on March 7, 1963
Body temperature regulation in mice resuscitated from deep hypothermia
Authors: Sudak Frederick N. , Essman Walter B. , Shen E. Mei 
Published: December 2017

Body temperature regulation was studied in mice following resuscitation from deep hypothermia induced by means of the closed-vessel cooling technique. Forty per cent of the animals cooled to and maintained at a colonic temperature below 5 C (lowest mean colonic temperature = 1.5 C) failed to demonstrate body temperature regulation when exposed to 2 C air for 30 min at 7-day intervals for a period of 70 days following resuscitation. Mice cooled to 5 C and immediately resuscitated showed a temporary loss in body temperature regulation. Loss of body temperature control did not occur in any of the control groups. Histological examination of midbrain sections taken from animals in each group showed pathological changes. There was no correlation between body temperature regulation and brain pathology. Mice resuscitated from sustained deep hypothermia showed impaired body temperature regulation upon heat exposure (39 C for 60 min) 7 days later. These data indicate that mice subjected to prolonged deep hypothermia induced by means of the closed-vessel cooling technique show poikilothermic responses following recovery. Furthermore, permanent loss of body temperature regulation upon cold exposure may result from this procedure. Note: With the Technical Assistance of D. Pennec and D. Glaubinger poikilothermic responses; resuscitation of hypothermic mice Submitted on February 21, 1963
Effect of oxygen inhalation on cold thresholds
Authors: MacCanon D. M. , Resnik J. 
Published: December 2017

The effect of oxygen inhalation on cutaneous thresholds for cold sensation was determined by exposing a 50-cm2 area on the chest to a radiant cold source of variable intensity for 2-sec intervals in 11 healthy 23- to 26-yr-old nude subjects at two ambient temperatures. Oxygen breathing produced a similar significant increase in cold thresholds in both cool (22.4–26.5 C) and warm (36.6–39.3 C) environments. Observations at warm ambient temperatures substantiate the oxygen effect independent of suspected reflex vasoconstriction in the cool environment. environmental temperature Submitted on March 18, 1963
Discrepancy between heart rate and oxygen consumption during work in the warmth
Authors: Brouha Lucien , Maxfield Mary E. , Smith Paul E. , Stopps Gordon J. 
Published: December 2017

These experiments compare the usefulness of oxygen consumption and heart rate as indicators of the strain produced by repetitive work in various environments. When the length of the rest periods was determined by the time for oxygen consumption to return to its resting level, a steady state of heart rate and oxygen consumption was achieved in a comfortable environment. In warm surroundings, oxygen consumption reached again a steady state but the heart rate increased during repetitive work cycles. When the duration of the rest periods was arbitrarily fixed, both oxygen consumption and heart rate reached constant steady states in repeated work cycles when the environmental stress was light. When it was severe, oxygen consumption remained at the same average value from cycle to cycle and failed to indicate the presence of accumulated strain which was revealed by increasing heart rates. repetitive work; warm environment; female humans Submitted on July 13, 1961
Control mechanisms in blood fluidity: role of adenosine triphosphate
Authors: Pilgeram L. O. , Loegering D. A. 
Published: December 2017

A possible role for cellular energy metabolism in the control of the blood clotting mechanism has been shown. High-energy phosphate was found to strongly inhibit the recalcification time of plasma prepared with siliconized or glass surfaces. The nucleotide, adenosine triphosphate, in crystalline form and chromatographically pure, will inhibit or completely prevent coagulation in vitro. Reactivity is based primarily on the high-energy phosphate linkage and secondarily upon the nucleoside, adenosine. The principal site of action for ATP is on an unidentified precursor of thromboplastin. Available evidence indicates an important role for energy metabolism in the cellular mechanisms which effect a control over thromboplastin generation and its possible thrombotic and arteriosclerotic sequelae. cellular control mechanisms; blood fluidity; thrombosis arteriosclerosis; aging Submitted on July 1, 1963
Various hormone changes during simulated space stresses in the monkey
Authors: Winters W. D. 
Published: December 2017

Experiments were undertaken to study the alteration in urinary excretion of 17-ketogenic steroid, catecholamine, and urine output during several simulated space stresses, i.e., centrifugation, vibration, and isolation with restraint in the monkey. The results indicated a variability of responses depending on the type and degree of stress. Reduction in urine volume was observed in all instances. A fall in steroid and slight elevation in catecholamine excretion was observed following vibration and centrifugation. The centrifugation appeared to be slightly more stressful. Isolation with restraint appears to be a severe stress to the animals as demonstrated by a marked elevation of amine, and a marked reduction in both urine output and steroid excretion. daily urine volume; catecholamine excretion; 17-keto-genic steroid excretion; acceleration; centrifugation; isolation and restraint Submitted on September 24, 1962
Insensible weight loss of clothed resting subjects in comfort zone temperatures
Authors: Hall J. F. , Klemm F. K. 
Published: December 2017

Insensible weight loss rates of clothed sitting subjects exposed to various temperatures in the range (22–32 C) were measured with a precision system in which weight losses are balanced automatically, displayed on a digital voltmeter, and printed on paper as a function of time. Accuracy of the scale is ± 5 g. Thirty-nine experiments were conducted on ten male subjects wearing light clothing (0.9 clo), exposed 2 hr at 22, 23.9, 26.7, 29.4, and 32.2 C and constant (10 mm Hg) ambient water-vapor pressure. First hour was for equilibration. Mean skin and body temperatures were measured with 17 thermistors and rectal thermistor, respectively. At ambient temperatures 22–26.7 C insensible loss rate increased slightly (21–26.5 g/m2 hr). From 26.7 to 32.2 C, however, increase is marked (26.5–64 g/m2 hr) with an abrupt rate increase at 26.7 C ambient and at a mean skin temperature of 34.6 C. Importance of ambient air temperature as a control factor in total water loss of subjects in closed space systems is shown. insensible perspiration; body water deficit; skin water loss; closed space systems Submitted on April 4, 1963
Catecholamine excretion during heat deacclimatization
Authors: Hale Henry B. , Williams Edgar W. , Ellis James P. 
Published: December 2017

Sympathoadrenal activity was appraised in ten heat-acclimatized men over a 10-week period, beginning in late summer and ending in autumn. Two overnight urine samples per subject per week were analyzed for norepinephrine, epinephrine, creatinine, and urea. Evidence of relatively high sympathoadrenal activity was obtained in late summer, since a progressive decline appeared in autumn. The catecholamines were shown to relate either to weekly mean maximum temperature or to weekly mean solar radiation. Catecholamine excretion also tended to vary inversely with urea excretion. epinephrine excretion; norepinephrine excretion; heat acclimatization; sympathoadrenal activity in hot climate Submitted on February 25, 1963
Pulmonary function during norepinephrine-induced calorigenesis in cold-acclimatized rats
Authors: Evonuk Eugene , Hannon John P. 
Published: December 2017

The effects of cold acclimatization on pulmonary function during norepinephrine-induced calorigenesis were studied. Norepinephrine resulted in a marked increase (85%) in the pulmonary minute volume in both the warm- and cold-acclimatized rats. This increase in the warm-acclimatized rats was accomplished entirely by increasing the respiratory rate, whereas in the cold-acclimatized rats, the increase in pulmonary minute volume was achieved for the most part by increasing the tidal volume with a slight increase in respiratory rate. Cold acclimatization was associated with a greater “efficiency of oxygen extraction” before, during, and after the infusion of norepinephrine. pulmonary minute volume; respiratory rate; oxygen extraction Submitted on December 6, 1962
Sweat sodium content and flow rate in cystic fibrosis of the pancreas
Authors: Sibinga Maarten S. , Barbero Giulio J. 
Published: December 2017

Sweat of healthy children and patients with cystic fibrosis was compared following stimulation with methacholine by iontophoresis and by intradermal injection. Sweat samples were collected at 10 min and subsequent 20-min intervals. With injection of methacholine higher initial secretory rates and sodium concentrations were obtained and a steeper decline of these parameters followed, while iontophoresis resulted in a more sustained sweating response. Sodium concentrations in sweat were from 3.45 to 6.75 times elevated in cystic fibrosis. A definite relation of Na content and secretory rate was established for normal children as well as for patients with cystic fibrosis. children; methacholine Submitted on November 16, 1962
Some biochemical and physiological features of normal monkeys (Macaca radiata)
Authors: Srikantia S. G. , Gopalan C. 
Published: December 2017

Determinations of body-fluid spaces with antipyrine for total-body water and sodium thiocyanate for extracellular fluid volume, hematological indices, and several serum constituents in about 500 Macaca radiata monkeys revealed that most of the values obtained were very similar to values obtained in man. body fluid spaces; hematology Submitted on April 22, 1963
The photodermoplanimeter
Authors: Halliday E. C. , Hugo T. J. 
Published: December 2017

A description is given of an instrument which measures the radiation area of the human body. An isotropic flux of light is produced in a large integrating vessel and when a human subject whose skin has been suitably blackened enters the vessel, the light intensity at a window in the wall of the vessel is decreased. A photometric measurement of this decrease enables the effective area of the surface of the skin of the subject to be measured with an accuracy of better than 1%. The instrument enables measurements to be made on large numbers of subjects rapidly and reliably. human body surface; radiation area; photometric measurement Submitted on April 5, 1963
Energy cost, fluid and electrolyte balance in subarctic survival situations
Authors: Rogers Terence A. , Setliff James A. , Klopping John C. 
Published: December 2017

In two experiments a total of 12 men were subjected to 5 days of starvation under survival conditions in the winter subarctic. They wore flying clothing rated at 3.5 clo. The caloric cost, as calculated from oxygen consumption, was 2,300 kcal/m2 for the first day and 2,000 kcal/m2 for subsequent days at ambient temperatures of -30 C. At -10 C the cost of subsequent days fell to 1,500 kcal/m2. The subjects lost 8% of body weight but regained 5% body weight after 5 days refeeding on a barely maintenance diet. One-third of the original (8%) weight loss was due to an isotonic contraction of extracellular fluid. Changes in heart rate, pulse pressure, and hematocrit consistent with this fluid contraction were observed. Although the water intake did not exceed the 5-day urine volume (5 liters), the subjects did not experience thirst until after return to the warm. Note:(With the Technical Assistance of William P. Esser and Kermitt R. Skrettingland) caloric cost; cold exposure; electrolyte balance in starvation; fasting; fluid balance in starvation; IMP, integrating motor pneumotachograph; fat carbohydrate and protein catabolism in cold exposure and starvation; cold diuresis; sodium, potassium and acid-base balance in acute starvation Submitted on June 3, 1963
Pulmonary alveolar-vascular reflex
Authors: Halmagyi D. F. J. , Colebatch H. J. H. , Starzecki B. , Horner G. J. 
Published: December 2017

Lung mechanics and pulmonary circulation were studied in lightly anesthetized, spontaneously breathing, supine sheep. Aerosol atropine restored lung compliance (Cl) in animals after fluid inhalation. Ventilation-perfusion relationship was studied by comparing Cl and effective pulmonary capillary blood flow (Qe = 100 minus venous admixture in per cent of cardiac output). The relation between Cl and Qe in unpremedicated sheep before and after fluid inhalation suggested homeostatic redistribution of blood flow away from nonventilated areas. Compensation for nonventilated areas was enhanced by severe pulmonary hypertension and abolished by atropine or isoproterenol; vagotomy had no effect. Homeostasis therefore appears to depend on a local reflex response of the parasympathetic nervous system— “alveolar-vascular reflex.” Pulmonary hypertension of generalized alveolar hypoxia was a different reaction not blocked by atropine. Consistent with this analysis, an infusion of acetylcholine increased pulmonary arterial resistance. The increase in Cl which followed atropine or isoproterenol indicated that in addition to surface forces, smooth muscle contraction may result in closure of lung units. lung mechanics and pulmonary circulation; fluid aspiration; atropine aerosol effect on lung compliance (Cl) after fluid inhalation; isoproterenol restored Cl; local homeostatic reflex response to pulmonary hypoxia; parasympathetic control of pulmonary ventilation; lung compliance (Cl) and effective pulmonary capillary flow (Qe) correlation Submitted on March 25, 1963
Rheology and structure of blood suspensions
Authors: Charm S. E. , McComis W. , Kurland G. 
Published: December 2017

A structural model developed for kaolin suspensions was applied to blood in order to determine the structure and strength of the red cell suspensions. The yield stress of red cell suspensions determined in settling experiments agreed with the yield stress determined from shear stress-shear rate information employing Casson's equation. Theoretical considerations indicate that the shear stress-shear rate curve for blood should approach a straight line. This was found to be true at shear rates above 40 sec-1. The slope of this line was predicted from calculations based on sedimentation experiments and a modified Einstein's equation. The data suggest that the curvature of the shear stress-shear rate plot at low shear rates is due to aggregates of cells which break down under increasing shear rate, resulting finally in individual flocs. It is suggested that a floc consists of one to four cells with adhering plasma. The aggregate was calculated to have twice as much plasma associated with it as does a floc. However, the size of the aggregate could not be determined since the number of flocs associated with an aggregate could not be determined. shear stress-shear rate curve; red cell floc; red cell aggregate; sedimentation rate; blood viscosity and flow Submitted on February 28, 1963