bluuebunny/crossref_metadata_2025_split huggingface dataset:
SOME OBSERVATIONS ON THE CENTRAL PATHWAY FOR CUTANEOUS IMPULSES IN THE CAT
Authors: Gaze R. M. , Gordon G. 
Published: December 2014

1. The responses of single neural units in the cat's thalamus to electrical stimulation of the saphenous nerve, and to mechanical stimulation of the saphenous skin area, have been studied after chronic lesions had been made in various parts of the spinal pathway.2. Thalamic responses to stimulating hairs, mediated by saphenous fibres of the aβγ group, were found after the whole spinal cord had been cut except for the dorsal columns. These were both ipsilateral and contralateral to the peripheral stimulus.3. Thalamic responses to a variety of cutaneous stimuli were found after cutting the dorsal columns, one or both ventrolateral columns having been left intact. These included responses to stimulating hairs, mediated by saphenous fibres of the aβγ group, and responses to stronger stimuli, mediated by the saphenous δ group.4. In experiments in which the spinal cord was cut across except for the ventrolateral column of one or other side, it was found that impulses can activate the ipsilateral thalamus by crossing the midline below the lesion and crossing back at some point above it. Impulses activating the contralateral thalamus can cross the midline at some point above the lesion. These are probably only examples of a variety of possible paths for such impulses.5. These results do not support any simple diagrammatic representation of the afferent cutaneous pathway.
FALL IN THE INULIN CLEARANCE FOLLOWING A SINGLE INJECTION
Authors: Barnard H. F. , Bassir O. , Hough J. M. 
Published: December 2014

1. The inulin content of plasma and urine has been followed for 24 to 48 hours after a single injection in a number of adults.2. Successive inulin clearances during this period show a marked fall.3. Reasons are given for considering delay or incomplete recovery of urine as relatively minor importance in causing the fall.4. As probable causes of the fall, tubular reabsorption and inhomogeneity of the inulin are discussed.
SOME LABORATORY AND FIELD OBSERVATIONS ON THE HARVARD PACK TEST
Authors: Ladell W. S. S. , Kenney R. A. 
Published: December 2014

1. In laboratory trials the effects on the fitness index of varying stepping rate, stool height and time of pulse counts, from the standard ones used in the Harvard pack test, were investigated statistically.2. The observed index was diminished by decreasing the stepping rate or by increasing the stool height. No significant effect on the index was found when the final pulse count was taken earlier than standard.3. The validity of comparisons between indices determined using the standard or non‐standard routines respectively is discussed.4. In field trials a fall in the mean fitness index of 100 African troops in the course of a two‐month military exercise was found comparable to that attributed by other workers to “tropical fatigue”.5. The possible causes of this deterioration in fitness are examined. The most probable appeared to be repeated daily physical stress accompanied by chronic lack of sleep.
A SEPARATE AFFERENT NERVE SUPPLY FROM THE EXTRAOCULAR MUSCLES OF GOATS
Authors: Whitteridge D. 
Published: December 2014

1. The presence of branches of the fifth nerve distributed to the extraocular muscles in the goat has been confirmed.2. These branches have been found to carry mainly impulses from muscle spindles. Impulses from tendon receptors have also been found.3. They probably also carry impulses from pain endings in the muscles.4. The γ efferents to the muscle spindles run in the motor nerve fibres. They have not been found in the branches from the fifth nerve.
THE SIMILAR EFFECT OF CHYLOMICRA AND ETHANOLAMINE PHOSPHATIDE ON THE GENERATION OF THROMBIN DURING COAGULATION
Authors: Robinson D. S. , Poole J. C. F. 
Published: December 2014

1. The addition of rat chylomicra to plasma from which the particulate fat has been removed by high‐speed centrifugation greatly increases the amount of thrombin formed in a thrombin generation test.2. Several brain ethanolamine phosphatide preparations also markedly increase the amount of thrombin generated in similar tests. Serine phosphatide, inositol phosphatide and lecithin are inactive.3. Acid hydrolysates of chyle contain a substance resembling ethanolamine in its ionophoretic and chromatographic behaviour. Also present are substances resembling choline and serine.4. It is concluded that ethanolamine phosphatide is probably the phosphatide component of the chylomicron which is active in the coagulation tests.
INTRACELLULAR RECORDS FROM BETZ CELLS IN THE CAT
Authors: Phillips C. G. 
Published: December 2014

1. Methods have been described by which neurones in the motor cortex of cats have been successfully impaled by intracellular microelectrodes.2. The majority of the cells thus entered have shown large stable resting potentials of ‐ 60 to ‐ 90 mV, without natural subthreshold voltage fluctuation or any discharge of impulses. Electrical stimulation of the overlying cortex did not excite them, even when it was strong enough to cause movements of the limbs.3. Twenty‐six cells impaled in 69 experiments were proved, by their response to antidromic stimulation of the medullary pyramid, to be cells of origin of pyramidal axones (loosely described as Betz cells throughout this paper).4. These cells were naturally active from time to time under the light anæsthesia employed. Their membrane potentials oscillated below the threshold for firing, and, whenever this level was reached, impulses were discharged, sporadically or in regular trains at frequencies up to 50 c./s.5. Stronger stimulation of the pyramidal tract caused delayed excitatory depolarizations and inhibitory hyperpolarizations to follow the antidromic impulses which invaded the Betz cells.
CORTICAL MOTOR THRESHOLD AND THE THRESHOLDS AND DISTRIBUTION OF EXCITED BETZ CELLS IN THE CAT
Authors: Phillips C. G. 
Published: December 2014

1. In “monopolar” stimulation of the motor cortex of lightly anæsthetized cats with single rectangular pulses of the 10·0 msec. duration, the least current needed to evoke a flick movement of the forelimb is 0·5 to 1·5 mA. This motor threshold has been compared with the thresholds for single and for iterative firing of single Betz cells. Some lay as close as possible to the point of stimulation, but at different depths in the wall of the cruciate sulcus. Others lay at different horizontal distances and in different directions from the stimulated point.2. Sixteen Betz cells (proved to be such by intracellular recording of their responses to antidromic stimulation of the pyramidal tract) were stimulated from the nearest surface point: eight with surface positive and surface negative pulses, eight with surface negative only.3. Cells on the convexity of a gyrus have thresholds of 25 to 50 µA (surface positive) for the discharge of a single impulse. Thresholds of cells in the depths of the sulcus do not usually exceed 250 µA. For the discharge of a high frequency burst the lowest threshold is 100 µA (surface positive).4. Eight Betz cells were also stimulated from one or more distant points. High‐frequency bursts were obtained in response to shocks at points 4 to 6 mm. away. These shocks were usually below the threshold for movement.5. It is concluded that in punctate stimulation of the cat's motor cortex with single 10 msec. shocks just strong enough to cause movement, Betz cells as far as 4 mm. distant in all directions (including cells lying on the far side and in the walls of the cruciate sulcus) are stirred into high‐frequency iterative firing. It is probable that there is also an outer zone of Betz cells firing single impulses.
HISTOLOGICAL CHANGES IN RATS RENDERED HYPERGLYCÆMIC BY INJECTION OF DEHYDROASCORBIC ACID
Authors: MacDonald Mary K. , Bhattacharya S. K. 
Published: December 2014

1. Rats made hyperglycæmic by repeated intravenous injections of dehydroascorbic acid (DHA) were killed 24 hrs. (Group 1) and four days (Group 2) after the last DHA injection, and the pancreas, kidneys, liver, adrenals and thyroid were examined histologically.2. The most marked lesions were found in the islets of Langerhans of the pancreas. In Group 1 animals there was degranulation and shrinkage of the β‐cells, pyknosis of their nuclei, and occasionally vacuolation of their cytoplasm; rarely, actual disintegration of cells was observed. No glycogen was stainable in the β‐cells. In Group 2 rats the islets were small: the β‐cells were reduced in numbers, shrunken and usually agranular, with pyknotic nuclei. Cytoplasmic vacuolation was obvious, and though some glycogen was demonstrable in the cells, all the vacuolation could not be accounted for in this way.3. The kidneys showed no significant degenerative change in either group, but there was some glycogen storage in the tubular cells of Group 2 rats.4. In the adrenal cortices, a reduction of Sudanophil and Feulgenpositive material was observed in the zona glomerulosa and the zona fasciculata in the males of both groups, while no such change could be demonstrated in the females of Group 2.5. No change of note was found in the livers or thyroids of the experimental animals.6. The main lesions occurring as a result of injection of IDHA, those in the islets of Langerhans, are thus very similar to the lesions of experimental alloxan diabetes, but it appears that for comparable islet damage, DHA produces higher blood sugar concentrations.
THE EFFECT OF CO2 AND 02 CONTENT OF THE BLOOD ON THE FREEZING POINT OF THE PLASMA
Authors: Meschia Giacomo , Barron Donald H. 
Published: December 2014

1. The effect of CO2 and 02 on the osmotic pressure of plasma has been estimated by measuring the freezing point depression of plasma whose blood had been equilibrated at 38° C. with gas mixtures of different composition.2. At constant oxygenation, for each millimol of CO2 added to one kg. of water of the blood, the osmotic pressure of plasma rises by 0·9 milliosmols per kg. of water.3. If the CO2 content of blood is kept constant, the reduction of one millimol of hæmoglobin (m. wt. 17,000) per kg. of water lowers the osmotic pressure of blood by about 0·3 milliosmol per kg. of water.4. The biochemical implications of these findings are discussed.
THE EFFECTS OF EQUAL AND LIMITED RATIONS OF WATER, AND OF 1, 2 AND 3 PER CENT SOLUTIONS OF SODIUM CHLORIDE ON PARTIALLY NEPHRECTOMIZED AND NORMAL RATS
Authors: McCance R. A. , Morrison A. B. 
Published: December 2014

1. Groups of rats were subjected to 5/6 nephrectomy to make the concentrating power of their kidneys resemble that of man. Three to four weeks later they were placed in individual metabolism cages and given no food for four days, and 4 ml. of water or 4 ml. of 1, 2 or 3 per cent sodium chloride solution daily by stomach tube. Some normal rats were starved and made hydropenic in the same way. At the end of the four days the rats were killed and their urine and bodies analysed.2. Starvation and partial dehydration were found to bring about a series of changes which may be summarized as follows: a fall in the body weight to which both the fat and the lean body mass contributed; a fall in the percentage of water in the lean body mass; a fall in the inulin space as a percentage of the lean body mass and a very small fall in the chloride space; a rise in the serum chloride; a rise in the percentage of sodium, chloride and of N in the body, but a fall in the percentage of potassium and consequently a rise in the N/K ratio of the body.3. Most of these changes were progressively intensified by substituting 1, 2 and 3 per cent saline for the ration of water, and other progressively unfavourable effects were revealed: e.g. the volumes of urine rose and so did the total loss of body water from all sources; more tissue protein was broken down and the formation of urea was increased, and more potassium was excreted in the urine.4. The breakdown of tissue proteins and the formation of urea were considerably greater three and four weeks after partial nephrectomy than they were in animals upon which no operation had been performed. The operation of total nephrectomy greatly increased the formation of urea during the ensuing three hours.
THE INFLUENCE OF GRADED EXERCISES ON THE OXYGEN CONSUMPTION, PULMONARY VENTILATION AND HEART RATE OF YOUNG AND ELDERLY MEN
Authors: Durnin J. V. G. A. , Mikulicic V. 
Published: December 2014

1. The effects of exercise were compared on two groups of healthy men, the one aged 20–30 years and the other aged 55–65. There were 12 men in each group.2. Four grades of exercise were used, two on an arm ergometer and two on a treadmill. The first arm exercise was light in nature, involving an average energy expenditure of just over 4 kcal/min. The second arm exercise and the first treadmill exercise, walking on the level at 3·7 m.p.h., were of moderate severity. The second degree on the treadmill, walking on the level at 4·3 m.p.h., was more strenuous.3. Oxygen consumption, pulmonary ventilation and heart rates were recorded during the exercises, and the heart rate and blood pressure were followed during the first 10 min. after the work.4. There was no significant difference in these measurements, nor in oxygen extraction or ventilation equivalent for oxygen between the groups with both arm exercises. However, the lighter exercise on the treadmill, which for the young men made a similar metabolic demand to the second arm exercise, gave significantly different values for the elderly. The older men used more energy, had a lower respiratory efficiency and higher pulse rates for the walking than the young men. The heavier treadmill exercise further increased these differences between young and old. The elderly men thus seemed to be able to do even quite hard exercise very efficiently if they were stationary, whereas the movements of walking caused a marked lowering in their efficiency.5. The detailed results are discussed and compared with some finding of other authors.
CORTISONE INDUCED IMPAIRMENT OF GLUCOSE TOLERANCE IN THE DETECTION OF THE DIABETIC DIATHESIS
Authors: Duncan L. J. P. 
Published: December 2014

1. The effect of cortisone on glucose tolerance was investigated by the administration of 200 mg. of cortisone 120 minutes before an intravenous glucose tolerance test. The resultant increment index (I.I.) has been compared with the control I.I.2. In 20 normal persons no change was observed following cortisone. In 16 patients with mild diabetes, the I.I. after cortisone was lower than the control I.I. by an average of 33 per cent. In 10 persons with latent diabetes, the I.I. after cortisone was lower than the control I.I. by an average of 38·5 per cent. Nineteen persons suspected of being in a prediabetic state were tested, and in 9, cortisone induced a lowering of the I.I. by at least 30 per cent of the control I.I. value. Of these patients, two have subsequently become clinically diabetic. In no other persons tested was this cortisone‐induced impairment of glucose tolerance observed.3. It is suggested that the use of an intravenous technique for the determination of glucose tolerance is the most precise measure of that function, and that the impairment of glucose tolerance induced by preliminary administration of cortisone makes it possible to diagnose the diabetic diathesis before any defect in carbohydrate tolerance is demonstrable by other laboratory tests.
THE DISTRIBUTION OF CAROTID AND VERTEBRAL BLOOD IN THE BRAIN AND SPINAL CORD OF THE GOAT
Authors: Andersson B. , Jewell P. A. 
Published: December 2014

1. The distribution of the carotid and vertebral arteries in the brain and spinal cord of the goat have been determined by the infusion of coloured suspensions in the living animal and subsequent histological examination of the tissues.2. Blood flow in the basilar artery is in a caudal direction so that the brain is virtually entirely supplied by carotid blood; in some individuals vertebral blood may reach the posterior medulla.3. The carotid rete does not provide admixture of blood from the two carotids under normal conditions of inflow, and this is so whether the animal is anæsthetized and supine, or conscious and standing in normal posture.
PROTEIN IN DYING LIVER CELLS
Authors: Dixon Kendal C. , McCullagh G. P. 
Published: December 2014

1. The distribution of protein was studied in liver cells of rats poisoned by carbon tetrachloride.2. The swollen hydropic cells, which are usually located in a midzonal position in the injured lobules, lose nearly all their cytoplasmic protein. These cells are filled by foamy vacuoles bounded by tenuous films of cytoplasm.3. The centrally situated necrotic cells, on the other hand, retain abundant cytoplasmic protein, although the cytoplasm of these cells loses RNA and their nuclei show karyorrhexis and karyolysis.4. The varying degree of injury to the liver cells may depend on initial cellular swelling; this may establish a gradient of ischæmia in the liver lobules with its maximum effect at the centre of the lobule where the cells are most severely damaged.5. Autolysis of protein may require the prior absorption of water by intact osmotic systems in the partially damaged cells. This view would account for the substantial loss of protein from the swollen hydropic cells, and the persistence of protein in the more acutely injured necrotic elements in which osmosis is no longer possible.
EFFECT OF ANÆSTHETICS ON BARORECEPTOR REFLEXES
Authors: Robertson J. D. , Swan A. A. B. 
Published: December 2014

1. The carotid sinus in cats, isolated from the rest of the circulation but with its nerve supply intact, was perfused with ether and chloroform in various concentrations in buffered Tyrode solution. The increased sensitivity of the baroreceptors which these anæsthetics produce is great enough to cause reflex changes in systemic blood pressure and in heart rate under these conditions.2. Perfusion with high concentrations of ether (300 mg. per cent W/V) and chloroform (100 mg. per cent W/V) rapidly inactivated the baroreceptors.3. The fall in blood pressure produced by the sudden inhalation of ether, chloroform and trichlorethylene was recorded in cats before and after cutting the baroreceptors. The fall of pressure was greatly reduced in 7 of the 9 experiments by baroreceptor denervation, and it was concluded that increased sensitivity of the baroreceptors plays an important part in producing the cardiovascular changes that follow the rapid inhalation of these volatile anæsthetics.
PIGMENT IN THE HARDERIAN GLANDS OF MICE EXPOSED TO A HOT ENVIRONMENT
Authors: Collins K. J. 
Published: December 2014

1. Examination of the Harderian glands of 21‐week‐old inbred and hybrid strains of mice reveals that the glands may contain at least two different pigments.2. The colour of the gland appears to be an inherited character due to the presence of a “melanin‐like” pigment.3. Different strains of mice also possess varying amounts of porphyrin pigment which fluoresces under ultra‐violet light.4. An increase in the porphyrin content of the Harderian glands can be produced by exposure to an environment of 91° F. dry bulb and 85° F. wet bulb.5. A condition similar to chromodacryorrhœa in the rat can be induced in heat‐exposed mice by intraperitoneal injections of acetylcholine.
MORTALITY, GROWTH AND LIVER GLYCOGEN IN YOUNG MICE EXPOSED TO COLD
Authors: Barnett S. A. , Coleman Elizabeth M. , Manly Brenda M. 
Published: December 2014

Mice of four strains were reared at 21°C. and then transferred to ‐3°C., in individual cages with nesting material. Controls were kept in similar conditions at 21°C. Many of the mice of two A strains died when stressed by cold at the age of 3 weeks, but none at 5 or 12 weeks. Many C57BL and GFF mice died when stressed at 5 weeks. Death usually occurred during the first 3 days, often on the first day. All stressed mice lost weight, especially in the first 2 days; if they survived, they made up the lost weight but they grew more slowly than the controls at all stages.Mice reared at ‐3°C. and stressed in that temperature when 3 weeks old had a lower mortality than those transferred from 21°C., and survivors did not lose weight. Mice reared at ‐3°C. and transferred to 21°C. at 3 weeks, although initially lighter, grew quickly and after 1 week were as heavy as the controls.Three‐week‐old mice stressed at ‐3°C. lost liver glycogen quickly whether they had been reared at 21°C. or ‐3°C. This was not due to a failure to eat, and there was no evidence that death resulted from inability to mobilize carbohydrate reserves.
THE MAXIMAL ISOMETRIC TETANIC TENSIONS DEVELOPED BY MAMMALIAN MUSCLE, IN SITU, AT DIFFERENT TEMPERATURES
Authors: Cullingham Penelope J. , Lind A. R. , Morton Rosemary J. 
Published: December 2014

Variations in the maximum isometric tetanic tension developed at different muscle temperatures have been examined following direct and indirect stimulation of the tibialis anterior muscle of the cat. While the frequency of direct stimulation necessary to evoke maximum tension remained constant at about 120–160 cycles/sec., the frequency of indirect stimulation had to be varied with temperature to ensure supramaximal stimulation. At such optimal frequencies of indirect stimulation for different muscle temperatures, the length‐tension relationship remained unaltered at muscle temperatures between 20 and 40°C.Maximum isometric tetanic tensions were greatest at 38–40° C. A fall in muscle temperature to about 28° C. resulted in a fall in tension of only 5 per cent below that found at 40° C., but a further fall in muscle temperature to about 20° C. led to a reduction in the tension exerted to a value of 30–35 per cent less than that exerted at 40° C. Such tensions were slightly greater when evoked by direct than by indirect stimulation. The amount of this difference was 2–4 per cent at 40° C. and 7–8 per cent at 20° C. The evidence suggests, therefore, that when the frequency of stimulation is adjusted to the optimal rate for given temperatures, the greater proportion of the fall in tension is due to failure within the muscle fibre itself rather than to failure of the neuromuscular junction. The relationship of this finding to voluntary contractions is discussed.
PROTEIN IN DYING β‐CELLS OF THE PANCREATIC ISLETS
Authors: Dixon Kendal C. , King A. J. , Malinin Theodore 
Published: December 2014

The β‐cells of pancreatic islets, dying after injury by alloxan, were studied (1) by staining with oxidized tannin‐azo (OTA), which colours well the tannophilic protein both in islet and acinar cells, and (2) by successive treatment with neutral permanganate, Gomori's paraldehyde‐fuchsin and methylene blue, a method which effectively differentiates the β‐cells from the other cells of the pancreas.There was no rapid loss of tannophilic protein from the injured β‐cells which retained their granules stainable by paraldehyde‐fuchsin in the early stages of necrosis.The injured β‐cells were rapidly dissevered from one another and from the capillaries, which they normally encompass, and were thus transformed from mutually coherent epithelial units into isolated separate cells. It is suggested that alloxan may react with an external film of protein on the surface of the β‐cells so as to sever their mutual coherence and also their adherence to the walls of the capillaries. After separation from their vascular supply, the isolated β‐cells may then undergo ischæmic necrosis.Pyknosis was conspicuous in the nuclei of the dying β‐cells and was accompanied by an increase in tannophilic protein. The capacity of the cytoplasm of the injured β‐cells to stain with paraldehyde‐fuchsin and with OTA later declined, when the necrotic remnants had swollen and coalesced into indistinct cellular phantoms. Finally all remnants of the β‐cells disappeared and the islets were reoccupied by epithelial cells rich in tannophilic protein but devoid of granules stainable by paraldehyde‐fuchsin.