Detection and Visualization of Minor Irradiation-Induced Changes in Polytetrafluoroethylene (PTFE) by Raman Spectroscopy.

Exposure of polytetrafluoroethylene (PTFE) to argon plasma results in chemical modification of the polymer near the surface. Interestingly, PTFE modification can be induced by the sub-band gap ultraviolet (UV) irradiation. In the latter case, the changes in the chemical structure are very subtle, and they are practically invisible to conventional experimental techniques.

[The effect of protease tissue inhibitor on the activity of pancreatic proteolytic enzymes in in-vitro experiments].

The authors provide the data on in vitro experimental studies into the pharmacological properties of protease inhibitor obtained from bovine pancreas. It is shown that the preparation exerts an inhibitory action on pancreatic proteolytic enzymes such as trypsin, kallikrein, and elastase, drastically reduces the total proteolytic activity in pancreatic tissue homogenates. Comparison with the protease inhibitor gordox has demonstrated the inhibitory effect of both preparations to be practically similar.

[The biological action of chromium in relation to its valency].

The biological action of chromium in the human or animal organism depends on valency: normal physiological activity is displayed at the expense of CrIII, but toxic activity is more characteristic of CrVI. In the digestive tract and pulmonary tissue CrVI may restore in CrIII.