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Biomedical subjects

J Krajewski

Publications and source records attributed to J Krajewski.

At least 37 records · Page 2Linked to original sources
PubMed1983

[Goniometric studies of the human placental barrier in late pregnancy in EPH gestosis].

The structure of normal and toxemic pregnancy (EPH-gestosis) placenta was analysed by goniometric observation. Hitherto the most characteristic symptom of gestotic placenta demonstrable by measurements appeared to be thickening of the placental basallayer consisting of the basal membranes of the capillary endothelium and syncytiotrophoblast. Observations were now made on 20 normal placentas and on 20 ones with full-clinical gestotic symptoms. Specimens prepared by conventional methods were examined with a Philips EM 300 electron microscope, equipped with a goniometer stage. Measurements of the placental basal layer in three goniometer positions: 0 degrees, + 45 degrees, - 45 degrees, were made from negatives of electron micrographs with a final magnification 135,200 x. Data were analysed statistically using Wilcoxon's test. We also used the planimetric-statistic method of Casley-Smith and Davy. We found the thickness of the gestotic placental basal layer to be significantly less than in a normal one. Ultrastructural markers of transport through the feto-maternal blood barrier were more evident that in normals. We suppose the increased placental transport and decreased thickness of the placental basal layer could be compensatory reactions to the pathological lesions of gestotic pregnancy.

Basement Membrane↗
PubMed1982

[Use of the exposure test and the gas concentration measurements in the breathing zones for the evaluation of the workers' exposure to carbon disulfide].

Individual exposures to CS2 of 31 workers in a viscose rayon plant were examined by personal continuous air sampling and two versions of iodo-azide test (chronometric and titrimetric methods). The obtained results indicate that during occupational exposure there is no practical correlation between 8-hours time-weight average concentrations of CS2 in workers' breathing zones and the levels of CS2--metabolites in urine.

Air Pollutants↗
PubMed1981

[Gravimetric method of determining petroleum vapors in the air].

The method is based on drawing a known volume of air through a tube filled with activated carbon. Water vapour, adsorbed together with hydrocarbons is removed from charcoal by passing dry nitrogen. Drying with nitrogen does not result in any decrease in the quantity of hydrocarbon adsorbed. The quantity of hydrocarbons is determined by weighing the tube before and after sampling. The authors investigated the dynamics of drying the charcoal from adsorbed water as well as the efficiency of hydrocarbon adsorption on charcoal. In addition, they established the conditions for samples collection. The range of the method is from 250 g/m3 to 10 000 g/m3.

Air Pollutants↗
PubMed1981

[Occupational exposure to oil mist resulting from the use of cutting fluids].

Basing on literature data on toxic effects of oil mist as well as on the results of epidemiological studies, an airborne concentration of 5 mg/m3 of oil mist was suggested as a safe value and 10 mg/m3--as a limit value MAC. Analytical methods used to determine oil mist in the air were surveyed. The fluorescence method was regarded as the best one for evaluation of occupational exposure within low concentrations. Also the determination of polycyclic aromatic hydrocarbons seems to be advisable at the workstations where cutting fluids are used. A number of recommendations wee given aimed at a decrease in occupational risk at work with oils and oil emulsions used as a cooler.

Aerosols↗