Microextraction by packed sorbent optimized by statistical design of experiment as an approach to increase the sensitivity and selectivity of HPLC-UV determination of parabens in cosmetics.

A new approach to the quantitative analysis of parabens (PBs) in cosmetics, based on microextraction by packed sorbent (MEPS) followed by HPLC-UV detection is proposed. The development of optimal conditions for the sample preparation step was carried out in two stages. The potentially important factors that could influence the extraction were screened using the Plackett-Burman design approach, as a result of which, three statistically significant factors were selected from the nine studied.

Isomeric derivatives of triazoles as new toxic decomposition products of 1,1-dimethylhydrazine.

Unsymmetrical dimethylhydrazine (UDMH) is a rocket propellant for carrier rockets and missiles. UDMH is environmentally hostile compound, which easily forms a variety of toxic products of oxidative transformation. The liquidation of unused UDMH from retired launch sites is performed by the complete burning of UDMH-containing wastes.

Causes of unsatisfactory results of the use of mitomycin-C in endoscopic endonasal dacryocystorhinostomy.

Purpose: To study the antifibrotic effectiveness of mitomycin-C in the tissues of the ostium site after it application for endonasal endoscopic dacryocystorhinostomy.

Material And Methods: The study included 45 patients (48 cases) with primary obstruction of the nasolacrimal duct. All patients underwent endoscopic endonasal dacryocystorhinostomy (EEDCR).

[Structural analysis of the information value of lung ventilation parameters for assessment of bronchodilation response in patients with bronchial asthma].

The goal of this work was to perform structural analysis of the information value of lung ventilation parameters for assessment of bronchodilation response in patients with bronchial asthma. The information value of lung ventilation parameters is considered as a function of the initial level of ventilation disorders and the method of calculation of bronchodilation response. Structural analysis revealed that different lung ventilation parameters have different information value for assessment of bronchodilation response in patients with bronchial asthma.