bluuebunny/crossref_metadata_2025_split huggingface dataset:
Composition of palmar and forearm sweat
Authors: Collins K. J. 
Published: December 2017

Sodium, chloride, lactate, and potassium concentrations were determined in capsule samples of sweat collected simultaneously on the palm and forearm from six normal and three hyperhidrotic subjects. The rate of sweat output on the forearm induced in the normal subjects by indirect heating or by intradermal injection of acetyl-β-methylcholine always exceeded that on the palm. Similar sweat rates in the two regions were produced by exposing subjects with palmar hyperhidrosis to hot environments. The sodium and chloride concentrations in sweat from the two regions did not differ significantly. As with forearm sweat, palmar sweat sodium and chloride concentrations varied directly with the rate of secretion. Lactate and potassium concentrations were consistently higher in palmar samples. It is concluded that palmar sweat sodium chloride is well within the normal range of hypotonicity and that palmar sweat contains a slightly higher proportion of lactate and potassium than forearm sweat. Submitted on September 8, 1961
Influences of exercise and O2 on breath holding
Authors: Craig Albert B. , Halstead Lauro S. , Schmidt Gerhard H. , Schnier Brian R. 
Published: December 2017

The PaCOCO2 at the breaking point was found to be higher during exercise than during rest in four subjects. The breaking-point curve during exercise was elevated over the entire range of various oxygen concentrations studied, indicating that whatever the changes produced they are related to the contribution of CO2 to the urge to breathe and are independent of O2. At least part of the elevated PaCOCO2 may be accounted for by an overshoot of PaCOCO2 related to the rate of rise of Pco2. This was shown by increasing the rate of accumulation of CO2 by inhaling different O2-CO2 gas mixtures to simulate the increased CO2 production during exercise. However, certain calculations indicate that this is not the only difference between voluntary apnea during exercise as compared with that during rest. Submitted on June 30, 1961
Adrenal cortical response to chronic hypoxia
Authors: Hornbein Thomas F. 
Published: December 2017

Although acute oxygen lack causes increased adrenal cortical activity, there is evidence that continued exposure to hypoxia is accompanied by a return of adrenal cortical function to its sea level status. To evaluate the adrenal cortical response in men living for 14-21 days above 21,000 ft, urinary output of 17-hydroxycorticoids was measured in ten members of a Himalayan mountaineering expedition and compared to values obtained subsequently at sea level. No significant difference in 17-hydroxycorticoid output was observed between the two altitudes. The response of four subjects to the administration of Su-4885 (Methopyrapone) showed that the pituitary-adrenal cortical system was still capable of response to additional stimulation. Submitted on July 31, 1961
Respiratory response to forward acceleration compared with chest compression in dogs
Authors: Zechman Fred W. , Taylor Justin 
Published: December 2017

Six mongrel dogs were studied to determine if the increases in frequency of breathing characteristic of both chest compression and forward acceleration are initiated by the same vagal reflex. Since vagal section only abolished the response to chest compression, it is assumed that some other mechanism is primarily responsible for the rate increase characteristic of forward acceleration. Experiments are also described which suggest that the increased respiratory frequency may be attributed to a hypoxic drive. Note: (With the Technical Assistance of N. P. Clark) Submitted on December 7, 1961
Effect of reserpine on cardiovascular response to smoking
Authors: Westfall Thomas C. , Watts Daniel T. 
Published: December 2017

It has been shown that blood pressure and pulse rate are increased and skin temperature of the extremities is decreased when normal subjects smoke two-thirds of two cigarettes during a period of about 15 min. This standard smoking test has been performed on university students before and after treatment with reserpine (0.25 mg daily) to determine the effect of reserpine on cardiovascular responses to smoking. Blood pressure, pulse rate, finger and toe temperature changes were recorded before and during the smoking test in untreated students and after administration of reserpine for 14 days. The maximum change from control values in ten untreated students and after 14 days of reserpine, respectively, along with P values for differences were as follows: systolic blood pressure (mm Hg) +17, +8, P < .001; diastolic blood pressure (mm Hg) +14, +7, P < .001; pulse rate (beats/ min) +27, +13, P < .001; finger temperature (F) -6.4, -4.0, P < .1; toe temperature (F) -2.7, -4.2. Results show that the characteristic increase in blood pressure and pulse rate and, to a lesser extent, the decrease in finger temperature due to smoking are reduced by pretreatment with reserpine. Submitted on July 10, 1961
Local circulation in heart muscle studied with Na24 clearance method
Authors: Salisbury Peter F. , Cross Cecil E. , Oblath Robert W. , Rieben P. Andre 
Published: December 2017

Neutral, isotonic Na24Cl solution was injected into the left ventricular wall of open-chest dogs. The disappearance of local radioactivity was recorded. Individual injections that exceeded 5 mm3 retarded Na clearance. The rate of Na clearance from individual deposits did not measure coronary flow in absolute terms; however, when one hemodynamic parameter was suddenly changed 50–200 sec after the injection of a radioactive deposit, the changed Na clearance slope reflected directional variations of coronary flow. In ischemic regions of self-perfused hearts, elevation of aortic pressure that was paralleled by increased left ventricular and central coronary pressures did not always result in more rapid Na clearance. Submitted on November 24, 1961
Comparison of computed aortic blood velocity with that of electromagnetic flowmeter
Authors: Jones W. B. , Griffin J. B. 
Published: December 2017

The probe of an electromagnetic flowmeter was placed on the ascending aorta of five dogs. Aortic blood pressure was obtained from the same area. This pressure signal was fed into a simple computer circuit designed to solve a modification of the Navier-Stokes equation. The output of this circuit was assumed to be proportional to blood velocity and was compared directly with the velocity obtained with the electromagnetic flowmeter. The peak amplitudes and the stroke volumes (represented by the area under the velocity tracings), obtained simultaneously by the two different methods, were compared. Each dog was bled, transfused, and given methoxamine and nitroglycerin to produce a wide variation in stroke volume and blood pressure. A correlation coefficient of .93 was obtained from 350 paired stroke-volume values. Thus, it appears that in a wide variety of conditions, stroke volume may be derived from the aortic pressure pulse by the computer technique. Submitted on October 27, 1961
Influence of voluntary hyperventilation on cardiac output
Authors: Donevan R. E. , Anderson N. M. , Sekelj P. , Papp O. , McGregor M. 
Published: December 2017

The influence of voluntary hyperventilation on cardiac output was studied in six sitting and four supine subjects by the dye dilution method, using an ear oximeter. All studies were made during the performance of a steady work load of 150 kg-m/min. on a bicycle. There was a positive correlation between increase in ventilation and increase in cardiac output, the average ratio being 41 ml blood/liter ventilation increase. This was not affected by the duration of hyperventilation for periods up to 75 sec and was of the same order in the supine or sitting position. When the thoracic pressure changes of hyperventilation were simulated by raising airway resistance without increase in ventilation there was no correlation between changes in pressure and cardiac output. Thus, it could not be shown that the influence of hyperventilation on circulation was due to the mechanical effect of intrathoracic pressure on venous return, though the increased work of breathing may have been partly responsible for the change in cardiac output observed. Submitted on August 21, 1961
Elastic properties of single elastic fibers
Authors: Carton Robert W. , Dainauskas John , Clark John W. 
Published: December 2017

The elastic properties of elastic tissue were studied in a situation which minimized the effects of extraneous connective tissue and of the position of fibers in the elastic network. Single elastic fibers were dissected free from the ligamentum nuchae of the ox and were stretched under conditions of constant temperature and salinity. The strain was an exponential function of the applied tension. Single fibers were found somewhat less stretchable than the ligaments from which they were taken. The data given can be used to calculate the contribution of such elastic fibers to the behavior of an elastic system in which they are incorporated. Submitted on August 7, 1961
Effect of exercise, body and lung size on CO diffusion in athletes and nonathletes
Authors: Newman Faith , Smalley B. F. , Thomson M. L. 
Published: December 2017

A comparison of pulmonary alveolar-capillary diffusion was made on groups of 11 athletes and 9 nonathletes closely matched in body size and age. The modified Krogh breath-holding technique was employed both at rest and during exercise on a bicycle ergometer. Mean maximal values of Dco, kco, and Vo2 were significantly higher in athletes than in nonathletes ( P < 0.01). Pulmonary permeability (kco) rose rectilinearly with Vo2. The mean graph for athletes was parallel to but higher than that for nonathletes. The equality in slopes was attributed to the matching of the two groups in body size. Evidence that the higher level in athletes was due to their higher degree of training was provided by one nonathletic subject whose permeability rose during training to the mean athletic level. The relation between permeability, body and lung size, and Vo2 is discussed. Submitted on December 26, 1961
Effects of adrenaline and noradrenaline on ear vessels in cold- and warm-adapted rabbits
Authors: Honda Nishio , Judy William V. , Carlson Loren D. 
Published: December 2017

Cold exposure increases the secretion of catecholamines and enhances the effect of these hormones on metabolism. Whether the sensitivity of peripheral vessels to adrenaline and noradrenaline is altered by cold exposure has not been reported. Warm-adapted (27 ± 1 C) and cold-adapted (5 ± 1 C) rabbits were studied under chloralose or urethan anesthesia. Adrenline and noradrenaline were infused (3 μg/kg/min) through an car vein. Colonic plus car temperature, ECG, blood flow, and venous pressure in the ear were measured. Compliance of ear veins was calculated from the ΔV/ΔaP at pressures of 20 and 30 mm Hg. After prolonged cold exposure rabbits responded to catecholamine infusion (adrenaline and noradrenaline) with less change in heart rate during infusion and a more rapid return to control levels following infusion; with less decrease in ear temperature during infusion and a more rapid return to control levels following infusion, less increase in peripheral resistance, and less effect on compliance of the capacitance vessels (veins). The infusion caused a slight rise in colonic temperature in both groups. Submitted on March 19, 1962
Mechanical efficiency of rhythmic and paced work of lifting
Authors: Rönnholm Nils , Karvonen Martti J. , Lapinleimu Veikko O. 
Published: December 2017

Weights of from 2 to 10 kg were lifted to levels 5–44 cm higher and back again at the rate of 10–40 cycles/min. The optimum rate in terms of energetic efficiency was 20–30 lifts/min. With this rate, a load of 5 kg, and a lift of 12 cm, about half as much energy was expended when the subjects were permitted rapid, rhythmic completion of lifting and a compensatory pause during each frac12 min of scheduled work as when the same amount of work was performed at equal intervals throughout. The difference between rhythmic and paced work diminished to zero as the number of lifts was increased to 40/min. At loads of 2 and 10 kg and also over the distance of 5 and 44 cm, paced and rhythmic work required equal energy expenditure. The heart rate was also slower in rhythmic than in paced work. The difference was largest (16/min) when lifting 5 kg over 12 cm at the rate of 30 lifts/min. The introduction of an element of rhythm (and compensatory pause) thus resulted in a marked saving of physiological effort under strictly defined conditions. Submitted on November 13, 1961
Pulmonary diffusion in the dog lung
Authors: Niden Albert H. , Mittman Charles , Burrows Benjamin 
Published: December 2017

Methods have been presented for assessing pulmonary diffusion by the “equilibration technique” in the experimental intact dog and perfused lung while controlling ventilation with a whole body respirator. No significant change in diffusion of carbon monoxide was noted between open and closed chest anesthetized animals, with duration of anesthesia in the intact dog, or with duration of perfusion of the isolated dog's lung. There was no demonstrable difference in diffusion when arterialized blood was used as the perfusate in place of mixed venous blood in the lung perfusions suggesting that within the range studied the Po2, Pco2, and pH of pulmonary artery blood does not directly affect the diffusion of carbon monoxide. Retrograde perfusions of dogs' lungs did not significantly alter diffusion, suggesting that pulmonary venous resistance was not significantly lower than pulmonary arterial resistance in the perfused dog lung at the flows and pressures studied. The equilibration technique for measuring pulmonary diffusion and assessing the uniformity of diffusion was well suited to the study of pulmonary diffusing characteristics in the experimental animal. Submitted on January 8, 1962
Energy intake and expenditure of medical college women
Authors: Banerjee Sachchidananda , Mahindra Santosh Kumari 
Published: December 2017

Energy intake and output were determined in 11 women students of a medical college by analyzing the daily food consumed for protein, fat, and carbohydrate, recording the time spent in different activities, and analyzing the expired air during each activity. The period covered was 1 week. The average daily intake per student was 1,406 kcal and expenditure was 1,410 kcal. The average daily intake of protein, fat, and carbohydrate per girl was, respectively, 44.7 g, 43 g, and 210 g, which furnished 13, 27, and 60% of the total energy, respectively. Of the total energy 64% was expended in sleep, study, and rest, though these activities took 75% of the time. Ascending and descending stairs entailed more energy than cycling. Household work performed in a sitting position required more energy than standing activities (dancing, running, etc.). Energy intake and output just balanced, and the weight of the girls did not change during 1 week of the study. Submitted on March 13, 1962
Elevation of plasma antithrombin in the aging arteriosclerotic subject
Authors: Pilgeram L. O. , Schram A. C. , Loegering D. A. 
Published: December 2017

Plasma samples from aging human subjects who had recovered from the trauma of a myocardial infarct and who were not on anticoagulant therapy were assayed for antithrombin activity. Antithrombin was assayed by methods which measure the ability of plasma to destroy an excess of thrombin, human or bovine in origin. Residual thrombin was quantitated either by clotting time or by hydrolysis of TAME ( p-toluene sulfonyl-l-arginine methyl ester-HCl). All methods showed unequivocally that plasma antithrombin increases up to 33% ( P < 0.002) in subjects who have fully recovered from a thrombotic episode. Submitted on October 19, 1962
Nature of "imperfect" elasticity of articular cartilage
Authors: Elmore Stanley M. , Sokoloff Leon , Norris George , Carmeci Peter 
Published: December 2017

A low friction apparatus for measuring the compression of articular cartilage during static loading and subsequent recovery under conditions of immersion is described. The instrument system employed a specially designed balance lever and sensing transducer that recorded load and displacements as a function of time. Unlike the findings of past experiments conducted in air, measurements made in Hanks' balanced salt solution disclosed restitution of the compressed cartilage, following removal of loads up to 82.5 gm/mm2, to its original thickness. The measurements were affected by the tonicity of the immersion medium. The so-called imperfect elasticity of articular cartilage previously reported in the literature thus is an artifact. Submitted on August 7, 1962
Relation between pressure and diameter in main pulmonary artery of man
Authors: Greenfield Joseph C. , Griggs Douglas M. 
Published: December 2017

The pressure-diameter relationship in the main pulmonary artery of man was estimated in 11 patients undergoing open-heart surgery. The diameter was measured with a recording caliper sutured to the vessel wall. The lateral intravascular pressure was measured with a 20-gauge needle connected directly to a Statham P23Db strain gauge. In the eight patients with normal pulmonary artery pressure the results indicate: 1) the shapes of the pressure and diameter curves are similar; 2) the mean value for the ratio of change in radius to change in pressure (ΔR/ΔP) x 103 was 8.77 cm/cm H2O (±sd 2.10); 3) the mean value for the pressure-strain elastic modulus (Ep) was 159.0 g/cm2 (±sd 26.0); and 4) the mean change in cross-sectional area during an average cardiac cycle was 22.9% of the diastolic value. In three patients with pulmonary hypertension the value of both ΔR/ΔP and the pressure-strain elastic modulus was lower. Submitted on April 27, 1962
A veni-venomotor response to local congestion
Authors: Wallis William , Brenman Robert , Honig Carl R. 
Published: December 2017

Using the occluded venous segment technique a venoconstrictor response to local congestion was demonstrated in human limbs. Though the response appears to be dependent upon nerves, it may or may not involve the central nervous system. Results are discussed in terms of the mechanism and functional significance of the local vascular ℌreflex.ℍ Submitted on December 6, 1962
Respiratory control in uremic acidosis
Authors: Pauli H. G. , Reubi F. 
Published: December 2017

Lambertsen and co-workers were able to correlate increments in ventilation produced by a number of acute experimental acid-base derangements in man with combined shifts in H ion concentration in blood and cerebrospinal fluid. Comparing hyperventilation in a group of uremic acidotic patients with ventilation levels of a control group by the same criteria shows that the measured values in uremic subjects are lower than those predicted. The tentative conclusion may be drawn that in chronic renal failure the respiratory center is adapted to blood acidosis by an elevation of its threshold level for the H ion stimulus. Submitted on August 2, 1962
Effect of vascular pressure and blood flow on CO diffusion in the perfused dog lung
Authors: Burrows Benjamin , Niden Albert H. 
Published: December 2017

The effects of blood flow and vascular pressure on the pulmonary diffusing capacity for carbon monoxide have been studied independently in 18 isolated perfused dog lungs, using the “equilibration technique” for Dl determination. The Dl is a function of mean vascular pressure over a wide range of vascular tensions, suggesting that there are some lung capillaries with high closing pressures or that patent pulmonary capillaries are capable of dilating in response to an increase in their transmural pressure. A maximum Dl could not be obtained. Measured Dl is reduced with low rates of pulmonary blood flow, but its dependence on perfusion rate becomes slight as physiologic flow rates are approached. Nonuniform diffusing capacity: lung volume ratios throughout the lung are noted at both low intravascular pressure and low blood flow, indicating nonuniformity of capillary filling and/or nonuniformity of capillary erythrocyte transit times. Under the conditions of these experiments, Dl appears to be dependent on blood flow per se as well as related to changes in pulmonary vascular resistance. Submitted on November 14, 1962
Exercise blood flow changes in the human forearm during physical training
Authors: Rohter Frank D. , Rochelle Rene H. , Hyman Chester 
Published: December 2017

Forearm blood flow measurements were made with a venous occlusion plethysmograph on six competitive swimmers and six control subjects at rest and during a prescribed rhythmic exercise throughout a 13-week training and detraining program. The swimmers‗ mean exercise forearm blood flow increased progressively during the training program, reaching a maximum at the peak of training toward the end of the 5th week, after which it decreased to near posttraining levels during the period of detraining. The increase in the swimmer's exercise flow between the 1st week of training (4.02 ± 0.59 ml/100 ml min) and the 5th week of training (6.40 ± 0.56 ml/100 ml min) was statistically significant; their decrease in mean exercise blood flow during the 3rd week of detraining (4.70 ± 0.24 ml/100 ml min) was also statistically significant. There was no significant change in the swimmers' resting blood flow; nor were there significant changes in either the exercise or the resting blood flows of the control group. The technique for measuring blood flow in the forearm during rhythmic exercise is explained. Submitted on December 11, 1962
A simplified method for obtaining cerebrospinal fluid pressure measurements in the dog
Authors: Verdura Javier , White Robert J. , Kretchmer Henry 
Published: December 2017

A simplified method for recording the cerebrospinal fluid pressure in the dog is presented. It consists of introducing the polyethylene tube of a Rochester needle into the sub-arachnoid space at the level of the ventral atlanto-occipital joint. The advantages of this technique are: the dura mater is punctured under direct vision; a completely sealed fluid system results which permits direct inspection for cerebrospinal fluid leakage; and the animal may be placed in any anatomical position during the continuous monitoring of cerebrospinal fluid pressure. This method of measuring the cerebrospinal fluid pressure has been utilized in 30 canine experiments and has proven equally effective in recording cerebrospinal fluid pressures in monkeys. Submitted on December 21, 1962
Experimental ocular pathology related to corneal transmittance and infrared psychophysics
Authors: Dawson William W. 
Published: December 2017

The corneas of 26 cats were irradiated by a 3,250 K source at dose rates of 7.04 gcal/sec cm2. The incidence of cataract, corneal leukoma, and other anomalies was related to total dose levels which ranged from 25–400 gcal/cm2. Generation of lenticular opacities and associated long latent periods was related to current theory, corneal transmission, and intraocular absorption. Corneal spectral transmittance curves which cover the 200–3,200-mμ band were presented. An integration of the corneal transmission in the 700–2,700-mμ band indicates a mean transmission of 43%. Implications for studies of corneal sensibility using infrared stimuli are discussed. thermal psychophysics; infrared cataract; psychophysiology Submitted on March 11, 1963
Exposure chamber for animals at changed atmospheric conditions
Authors: Gans P. 
Published: December 2017

An airtight exposure chamber is described in which mice can be kept continuously in an atmosphere with a high carbon dioxide percentage, or with a low or high oxygen percentage. Advantages of the apparatus described are the absence of moving parts inside the chamber and, in the experiments with a low or high percentage of oxygen, the absorption of carbon dioxide and water outside the chamber, permitting the continuous treatment of the animals. animal exposure chamber; carbon dioxide exposure; oxygen exposure Submitted on January 4, 1963