Biomedical subjects

J C Smit

Publications and source records attributed to J C Smit.

4 recordsLinked to original sources

PubMed1993

Oxygen saturation during hemodialysis.

The aim of this study was to examine the saturation patterns of cuprofane and polysulfone membranes in hemodialysis patients, and to correlate that with permeability of the alveolar membrane, unloading of CO2 over the membranes, and production of oxygen free radicals. Polysulfone membranes did not have the same desaturation pattern as the cuprofane membranes. Both membranes were equally effective in the unloading of CO2, and so alveolar hypoventilation does not explain oxygen desaturation during hemodialysis. White blood cells have a central role in the parallel development of early leucopenia and hypoxemia. The precise mechanism is still unknown because there were no changes in permeability of the alveolar membrane or production of oxygen free radicals.

Biocompatible Materials↗

PubMed1990

[The relationship between creatinine clearance and glomerular filtration rate in the critically ill patient].

A study was undertaken to show that the determination of glomerular filtration rate with radio-labelled sodium chromate ethylenediaminetetra-acetic acid is a repeatable, easily performed and accurate examination in the critically ill patient. Differences in glomerular filtration rate were relatively small, with a phase difference of between -10,59 and 5,34. Creatinine clearance showed a greater variation over a corresponding period, with a difference of between -27,50 and -4,10. The study indicated that this method of determining glomerular filtration rate can be very useful in an intensive care unit, because it seems to be more accurate and easier to perform. Information is obtained more quickly than when the glomerular filtration rate is determined by means of creatinine clearance.

Acute Disease↗

PubMed1985

Indirect estimation of clinical chemical reference intervals from total hospital patient data: application of a modified Bhattacharya procedure.

Indirect methods for the determination of reference intervals utilise as input the total bulk of test results from all admitted hospital patients. One of the strongest arguments in favour of the use of these indirect methods is that one automatically obtains a one to one relationship between the selected population sample and the category of people for which the test results are intended. A study was conducted of the suitability of a modification of the indirect Bhattacharya method, which also permits the evaluation of heavily skewed distributions. The robustness of the method was evaluated by studying the homogeneity, stability and reproducibility of the hospital population in terms of the statistical parameters of the input distributions and of the resulting reference intervals for creatinine, uric acid and alanine aminotransferase. Finally, the age- and sex dependency for 15 clinical chemical parameters was compared with reported literature data.

Adult↗

PubMed1984

The striato-nigro-collicular pathway and explosive running behaviour: functional interaction between neostriatal dopamine and collicular GABA.

The nature of the functional interaction between neostriatal dopamine activity and collicular GABA activity was studied. To this end we analyzed the ability of apomorphine injections into the neostriatum (50-500 ng/0.5 microliters per side) to reinitiate explosive running behaviour in rats pretreated with a subthreshold dose of picrotoxin into the colliculus superior (30-80 ng/0.5 microliters per side). Apomorphine was found to reinitiate the former behaviour dose dependently and its effect could be antagonized by a very low dose of neostriatally applied haloperidol (250 ng/0.5 microliters per side). It was possible to delineate the most critical region within the structures studied. Evidence is presented in favour of the previously reported hypothesis that increasing dopaminergic neostriatal activity within the terminal region of the nitrostriatal pathway results in a decreasing GABAergic activity within the terminal region of the GABAergic striato-nigro-collicular pathway.

Animals↗