Search PubMed⌕ Search

Biomedical subjects

G Clausen

Publications and source records attributed to G Clausen.

50 records · Page 3Linked to original sources
PubMed1975

Mechanisms in acute oliguric renal failure induced by tetracycline infusion.

Tetracycline hydrochloride (TC), 30-70 mg/kg infused intravenously in dogs in the course of a few minutes, reduced clearance of inulin (Cin) and p-aminohippuric acid (CPAH) on an average to less than 5% of control. In spite of increased intrarenal pressure (approximately 50 mm Hg), electromagnetically recorded renal blood flow was preserved, indicating that the reduction of Cin and CPAH resulted from tubular obstruction, not renal vasoconstriction. The metabolic rate of the cortex and outer medulla fell to 69% of control after TC, as measured by the heat accumulation rate. Further reduction to basal metabolic level (30% of control) was reversibly produced by elevating ureteral pressure, suggesting that the high metabolic rate was caused by continued active reabsorption of sodium chloride at about half the control rate. Thus Cin greatly underestimated glomerular filtration rate in the TC-damaged kidney. From these results and the observation of TC-containing casts in the medullary tubules, we conclude that TC caused tubular obstruction and that leakage of inulin and PAH from the tubules occurred mainly distally to the major sodium-reabsorbing tubular segments.

Acute Kidney Injury↗
PubMedDate not supplied

Effect of reduced perfusion pressure and acetylcholine on local blood flow in tumors in the rat kidney.

The local blood flow (LBF) in a sarcoma and a hepatoma implanted into the rat kidney was examined during renal vasodilation, with and without increased total renal blood flow (RBF). Both tumor types had a control LBF of about 0.7 ml/min per g, i.e. 35 per cent or less as compared with the renal LBF, as simultaneously determined by the H2 gas clearance technique. The RBF averaged 4.6 ml/min per g as recorded electromagnetically. During about 20 mmHg reduction of renal arterial pressure the tumor LBF was maintained relative to the renal LBF, whether the RBF was autoregulated or not. Provided neoplastic vessels account for most of the vascular resistance to tumor blood flow, they must therefore possess autoregulatory ability. The tumor LBF was maintained when the RBF was maximally increased by continuous renal arterial infusion of acetylcholine. This may suggest that a neoplastic vessel vasodilatory response to acetylcholine prevented reduction of the tumor flow.

Acetylcholine↗
PubMedDate not supplied

[Method and organization of geriatric assessment].

The intention of a Geriatric Assessment (GA) is a more systematic and exact way to examine a wide range of activities of daily life. This can be achieved by the help of scientifically proved and standardized investigations which complete the medical judgment with objective and comparable results. This type of examination controls the selective observation of the investigator and makes reexamination easier. Moreover, this way of gaining information gives reliable hints about non-apparent or difficult-to-estimate risks of a patient. The methods of GA have to be adapted to different qualities of resources which will be assessed: physical resources should be assessed by standardized ways of observation; the patient's subjective well-being should be examined by standardized interviews. The standardized instruments of measurement are fairly independent from personal qualifications of the investigator.

Activities of Daily Living↗