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Z Piotrowski

Publications and source records attributed to Z Piotrowski.

62 records · Page 4Linked to original sources

Low molecular organic inactivators in differentiating organ origin of alpha-amylase in humans. Part I.

Alpha-amylases derived from pancreatic juice, saliva and granulocytes show different sensitivity to the low molecular organic inactivators. Pancreatic alpha-amylase is more susceptible to inhibitory activity of d-glyceraldehyde and d-mannitol and glycerol in comparison to alpha-amylase from saliva and granulocytes. Iodoacetate and urea exhibited inhibitory activity against granulocytic alpha-amylase and only a minute inactivation of salivary and pancreatic alpha-amylases was found. The most effective inhibition against all tested alpha-amylases was noted with dihydroxyacetone. We should stress, no evident differences were noted in the degree of sensitivity to this inactivator of the tested enzymes. The presumable mechanism of the inactivation of alpha-amylases with low molecular organic inactivators is briefly discussed. The procedure for the differentiation of organ origin of alpha-amylases is suggested.

Dihydroxyacetone↗

Adaptation of the circulatory system to frequently repeated submaximal workloads in the light of left ventricular contraction analysis.

In two groups of healthy men aged 20-22 years the left ventricular systolic time intervals were evaluated by the method of Weissler et al. during frequently repeated workloads and restitution. Each exercise was carried out on a Zimmerman cycle ergometer during 10 minutes, and was repeated five times at 50-minutes intervals from 8.00 o'clock a.m. Group I (15 subjects) performed the exercise at a stable workload which produced during the first exercise heart rate acceleration to 170/min, but gave a successive further rise in the heart rate during consecutive exercises. Group II (11 subjects) performed all exercises to a stable rise in heart rate to 170/min with decreasing workloads. It was found that successive exercises caused in both groups a similar decrease of the left ventricular ejection time index (LVETI), pre-ejection period (PEP), isovolumetric contraction time (ICT), and decrease of the PEP/LVET index (p less than 0.05). Each successive exercise began with higher values of LVETI, PEP, ICT and PEP/LVET than the first one. No significant differences were found in the values of left ventricular systolic time intervals in both groups (p greater than 0.05). The duration of restitution of normal values of the left ventricular systolic time intervals after successive exercises was not changing but the tolerance of these exercises measured by heart rate increase and work performed decreased successively.

Adult↗