摘要:

Summary.1In rabbits, simultaneous determinations have demonstrated identity between creatinine and thiosulphate clearances in 9 tests though for two other animals the values for the thiosulphate clearance were slightly lower than for the creatinine clearance.2In cats, on the other hand, the thiosulphate clearance when the plasma thiosulphate concentrations are low may have a value twice as high as that of the creatinine clearance,.whereas with a rising plasma thiosulphate concentration the difference approaches 0. Presumably the explanation is that the cat kidney can secrete thiosulphate.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00499.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.The possibility that the blood circulation in the brain, in an erect position, particularly under the influence of higher degrees of positive acceleration, is facilitated by a siphonic effect (fig. 1) is discussed. A prerequisite for this is that the vessels do not close at any point of the siphon. The weak points are the jugular veins and the small vessels in the brain. Direct measurements of the pressure of the cerebrospinal fluid during compression tests on the neck show that the jugular veins are far more pressure‐resistant than was earlier believed. It seems plausible that the small vessels in the brain are, in the first place, protected from collapse by the hydrostatic equilibrium between the blood and the cerebrospinal fluid. In all probability, a local artery‐dilating mechanism, at imminent over‐pressure in the cerebrospinal fluid, will contribute towards keeping the vessels open. It has been shown in Man that the pressure in the cerebrospinal fluid can be raised to degrees above the probable pressure in the cerebral capillaries without loss of consciousness and without any significant increase of the blood pre

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00500.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.In the present study experiments were made on rats to demonstrate by means of radioactive phosphorus the phosphate turnover in the tuber cinereum, adenohypophysis and ovaries during the phases of the reproductive cycle. The following results were obtained.1Tuber cinereum. The phosphate turnover reaches its peak during prooestrus. During the following phases it is markedly depressed.2Adenohypophysis. The phosphate turnover is considerably greater than in the tuber cinereum. Also in the adenohypophysis maximum metabolic activity was observed during prooestrus.3Ovary. The phosphate turnover is most intense during prooestrus and dioestrus.4These observations lend further support to the assumption that, from the functional point of view, the hypophyseal and diencephalic systems should be looked upon as a unity.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00501.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.By means of subtotal extirpation (comprising until 90 per cent.) of the lymphoid organs in the rat an attempt has been made to throw some light upon the possible connexion between these organs and the formation of serum proteins. In the early period after the operations an unspecific, slight increase of the serum globulin and a corresponding decrease of the serum albumin was demonstrated. After cessation of the mesenchymal reactions due to wound healing the serum proteins were found within the normal range. This seems to dispose of the organoid lymphoid tissue (thymus, lymph nodes and spleen) as an essential factor in the production of serum proteins.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00502.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

1A method is described for quantitative studies of reactive hyperaemia in the hind limbs of cats and dogs.2In cats the sensitivity of the small vessels to histamine varies within a very wide range, the magnitude of reactive hyperaemia, however, was found to be independent of the sensitivity of the vessels to histamine.3The magnitude of reactive hyperaemia is not reduced by rendering the small blood vessels completely insensitive to histamine in physiological concentrations.4Benadryl and related compounds completely annul the vasodilator effect of the minimal doses of histamine which produce maximal vasodilatation. The effect of larger doses of histamine, 5 times greater than the minimum dose and upwards, depending on the basic sensitivity to histamine, is not annulled or even diminished by any amount of antagonistic drug.5It is suggested that there are two types of receptors sensitive to histamine only one of which can be blocked by benadryl and related compounds.6It is demonstrated that adenosinetriphosphate is a very potent vasodilator, 0.1 ±0.2 y causing profound vasodilatation in the hind limbs when injected in the artery

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00503.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.Our observations indicate that:1Ghstrophanthin has a positive inotropic effect on hypodyna‐mic heart muscle of the frog.2The rise in contraction power produced by g‐strophanthin restores the extra tension developed during contraction to the assumed “normal” value and not higher.3If the partial pressure of oxygen surrounding the muscle is below a certain value, or if glycolysis is interfered with, g‐strophanthin does not restore the extra tension during contraction to the “normal” value.4G‐strophanthin does not influence the diastolic tension or the excitability before the appearance of

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00504.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.The micro‐electrode technique and the eye of the fully dark‐adapted cat have been used for measurements of off/on‐ratios and polarities of retinal elements tested with red, green and blue light.With red stimuli anodal and cathodal elements are distributed symmetrically over the off/on‐ratios, but, if the latter be determined with green or blue light, elements of lower off/on‐ratio tend to be cathodal those of higher off/on‐ratio anodal.The results are correlated with the relative values for the off/on‐ratios in the three

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00505.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.It has been maintained that the serum phosphatase of cats does not increase after common bile duct ligation as it does in other animals and man, but this assumption seems weakly supported.The present material comprises 39 cats in 10 of which the common bile duct has been ligated. The phosphatase is estimated by a modified Buch and Buch (King and Armstrong) method. The variability of serum phosphatase is appreciable but a few normal variations are noticed: Young cats have a high level. During pregnancy the phosphatase increases. The mean value for female cats is slightly higher than for males. 40 hours of fasting affords only an inconspicuous decrease.All cats with ligated common bile duct display an increase in serum phosphatase which begins on the 3rd day, reaches a maximum between the 4th and 17th day and then gradually decreases again. (See the mean curve, Fig. 3.) In one cat the bile flow was re‐established after two weeks of bile‐stasis and the serum phosphatase dropped to the normal level within a few days.Phosphatase in bile which is normally very high, decreases after common bile duct ligation.Urinary phosphatase vary very much normally. In the present material it does not increase during bile‐stasis. The hypothesis that the cat is able to compensate an increase in serum phosphatase by an increased output through the kidneys must therefore be abandoned. This is in keeping with the findings in cats with simultaneous common bile duct ligation and nephrectomy. Such animals do not show increase of serum phosphatase.In vitro experiments show that urea inhibits phosphatase.The investigation shows that with regard to phosphatase during obstructive jaundice, the cat differs less from other animals than was previously sup

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00506.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.The author has studied the growth of rats which as the sole source of nitrogen had received a mixture of the racemic forms of the 10 essential amino acids, synthetically produced. As nitrogen‐free diet, a mixture containing merely 0.002 % N was used.On a diet containing 10 % of this amino acid mixture a growth averaging 0.33 ± 0.14 grams per day was obtained.On a 20 % diet the growth of the rats averaged 0.89 ± 0.15 grams per day.On the other hand if the rats received 30 and 40 % amino acids in the diet, a decrease in weight, averaging 0.11 ±0.25 and 0.63 ±0.27 grams per day respectively, resulted. Thus, it must be considered that these synthetic amino acids in their racemic forms, contain some toxic matter, but exactly whence it emanates has not yet been ascertained.The synthesis of the 10 essential amino acids is briefly desc

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00507.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary.A method is described for determining arginine in urine and serum colorimetrically after adsorption in 70 % alcoholic solution on an alkaline column of A1203 and subsequent eluation with 1/10 n HC1.A few experiments regarding the reabsorption of arginine in the renal tubules are reported.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1948.tb00508.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY