摘要:

The authors try to precise the distribution of a Newtonian fluid at the level of a glass-tube bifurcation, a model grossly similar to blood vessel branches. Different types of bifurcations are obtained by means of translucent polyester resins. The length of the tubes is chosen in order not to alter the flow at the entrance and at the outlet (the length is approximately 90 times greater than the diameter). The fluid used is a mixture of water and glycerin; its viscosity is determined according to the temperature. The flow rates are measured by chronometry and the pressure with a pressure gauge made of capillary tubes. With certain hypotheses, the geometrical characteristics of the bifurcations permit the calculation of the induced charge losses; however, the shape of the area of influence and its evolution cannot be accurately precised.

ISSN:1018-1172    

DOI:10.1159/000157861

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Partial constriction of the portal vein in the rat impedes the development of renal hypertension, or decreases the already developed hypertension, respectively. Taking into consideration the fact that this effect could be observed also in that experimental form (left kidney clipped, the opposite one removed) in which the renin content of the clipped kidney and the increase of plasma renin activity could never be demonstrated – and even in the other experimental form (left kidney clipped, the opposite one untouched)- the protective effect was only present when the above-mentioned increase of renin level was already normalized: it seems that the protective effect of partial constriction of the portal vein does not take place due to the possible hepatic damage leading to an angiotensinogen production in a lower degre

ISSN:1018-1172    

DOI:10.1159/000157862

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

A significant increase of the fibrinolytic activity in the femoral vein blood after exercise of the legs has been observed. It is suggested that this increase is beneficial to the human organism from the point of view of practical therapeutics since fibrin clots oftener than platelet thrombi cause venous obstruction.The fibrinolytic activity was found to be lower in the blood obtained from the femoral vein in subjects confined to bed. It is tentatively suggested that this decrease may at least to some extent play a part in the increased incidence of phlebothrombosis in the lower limbs of patients who are bed-ridden.It is further suggested that the increase in the activator content in the blood after exercise of the leg is due to larger amounts of activator being contributed by the muscles during the accelerated bloodflow.

ISSN:1018-1172    

DOI:10.1159/000157863

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

In 122 aortas of swine fetuses of various ages the vasa sanguinea vasorum were investigated. The repartition of the vasa sanguinea vasorum was affected by age and the thickness of the media. Only aortic segments whose media included more than 29 lamellar units were vascularized.

ISSN:1018-1172    

DOI:10.1159/000157864

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The aorta of hypertensive rabbits has an increased content of water, sodium and fibrinogen. Fibrinogen catabolism is normal in most hypertensive animals and is, therefore, not a concomitant of increased vascular permeability but accelerated catabolism can be demonstrated when there is associated shock, red cell fragmentation due to DOCA angiopathy, hypertension in pregnancy, coincidental anoxia and acidosis, or in terminal uraemia. Under all these conditions, fibrin is deposited particularly in the kidney and may, therefore lead to further renal ischaemia.

ISSN:1018-1172    

DOI:10.1159/000157865

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

In experimental work on dogs, was performed a myocardial ischemia of differing duration. By means of a non-suture mammary-coronary artery anastomosis, a revascularisation was achieved. We realise that the diagnosis of the anastomostic potency using normal methods is not sufficiently clear. For this reason we tried to improve our diagnostic potential by means of antibody detection.

ISSN:1018-1172    

DOI:10.1159/000157866

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

For the free fatty acids in serum from normal adults was found a log-normal distribution. The free fatty acids were decreased by patients with chronic arteriosclerotic vascular diseases of the lower extremities.

ISSN:1018-1172    

DOI:10.1159/000157867

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The effect of lymph stasis on limb blood flow was studied in 38 dogs where lymph-oedema of one of the hindlimbs was induced by ligation of the lymphatics on the thigh and of the regional lymph-node. Haemodynamic examinations were conducted in 17 animals; total blood flow and the nutritive flow to the muscles and skin (86Rb extraction) were determined in both hindlimbs. Microcirculation was studied in 16 dogs by means of the india ink-gelatin injection method, the benzidine reaction and by the polyvinylchloride injection technique. In all cases specimens were taken from muscle, skin and subcutaneous connective tissue of both hindlimbs for light microscopic analysis. The results presented indicate an increase in total blood flow without any change in the nutritive flow to the skin or muscle in the lymph-oedematous limb. Lymph stasis induced intimal swelling and plasma infiltration of the intima and media of small vessels (pre-capillaries and metarterioles) of skin, muscles and subcutaneous tissue, which led to a blocked transportation of proteins. Small vessels of the limb with lymph-oedema were spottily dilated, whereas at other areas compressed capillaries could be seen. Evidence is supplied for the appearance of arteriovenous shunt circulation in lymph-oedema of the lower limb. In a previous study we observed that, unlike venous congestion, lymph-oedema of the limbs in man was accompanied by increased blood flow and a conspicuously low arteriovenous oxygen difference in the limb. (1) This finding led us to assume that chronic lymph stasis may induce arteriovenous shunt circulation. The present experiments were designed to study relative changes of total and nutritive limb blood flow and to examine alterations of the microcirculation in experimental lymph-oedema of the limb.

ISSN:1018-1172    

DOI:10.1159/000157868

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:1018-1172    

DOI:10.1159/000157869

出版商:S. Karger AG    

年代:1971

数据来源: Karger