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This consensus statement of Russian experts is based on a review of the relevant literature on the prevalence, diagnosis, and treatment of non-thrombotic and post-thrombotic venous obstruction, as well as management of patients after venous stenting. In the Part 1 we discussed the clinical manifestations of venous obstruction, the role of duplex ultrasound scan, CT venography, MR venography, direct venography, and intravascular ultrasound scan, as well as typical findings obtained by using these methods. The authors mentioned the functional assessment of venous outflow in healthy subjects and in those with obstruction and changes in them after the intervention. In conclusion, the authors formulated the suggestions for clinical recommendations on the diagnosis of chronic venous obstruction.

The method of continuous pressure decrease has been used to investigate limiting (attainable) stretches of ethane–nitrogen solutions. Experiments were conducted at temperatures of 260, 266, 270, and 276 K and at nitrogen concentrations in the solution of 0.5 and 1.5 mol%. Pressure decrease rates were taken in the range 0.01–0.1 MPa/s. Distribution functions of liquid boiling-up events in dependence on pressure have been obtained allowing one to determine the most probable (attainable) pressures of liquid boiling-up and the nucleation rate. The results are interpreted in terms of nucleation thermodynamics and kinetics in liquids on a solid surface containing inclusions that initiate the boiling-up processes. It is shown that for realizing homogeneous nucleation it is not necessarily required that the wettability is close to the ideal one. The reasons for the discrepancy between experimental data and predictions of homogeneous nucleation theory at nucleation rates J 6 s −1 m −3 are discussed.

The method of lifetime measurement is used to investigate the kinetics of spontaneous boiling-up of ethane–nitrogen solutions. Superheating temperatures Tn of solutions have been determined in experiments at pressure p = 1.0, 1.6 MPa and nitrogen concentration in ethane x = 0.5, 1.5 mol% in the nucleation rate range J = 1 × 104–2 × 108 s−1 m−3. At J > 3 × 106 s−1 m−3 one can observe a satisfactory agreement between experimental data and homogeneous nucleation theory with respect to the temperature dependence of the nucleation rate and a systematic disagreement in the superheating temperature. At x = 0.5 mol% attainable superheating temperatures achieved by experiment coincide within the experimental error with theoretical values, and at x = 1.5 mol% exceed them by approximately 1.7 K. It is shown that one possible reason of such “excess superheating” of a solution beyond the theoretical value of Tn may be the absence of adsorption equilibrium at the critical bubble–ambient solution interface.

В статье приведены материалы конференции «Актуальные вопросы эпидемиологии и инфекционных болезней, ВИЧ-инфекции».