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In this work, titanium carbonitrides were synthesized by self-propagating high-temperature synthesis (SHS) in nitrogen. For the first time, the synthesis of titanium carbonitrides by combustion was realized in nitrogen at atmospheric pressure. The synthesis was carried out by subjecting high-energy ball-milled titanium-carbon black powder mixtures to combustion in a nitrogen atmosphere. The influence of the ball milling time on the phase composition of the products of SHS conducted in the Ti+0.3C reaction mixture was studied. It was found that the titanium-carbon black mixtures need to be milled for a certain period of time for the combustion synthesis to yield a single-phase carbonitride product.

Acute appendicitis is the most frequent surgical disease complicating pregnancy. Accurate diagnosis is difficult due to atypical and misleading clinical manifestations. Surgeons frequently do not know about advantages and disadvantages of different diagnostic methods applied during pregnancy. Treatment of acute appendicitis in pregnant women remains the real challenge for surgeons. There are enough researches indicating on benefits and risks of both open and laparoscopic operations. The main risk is due to fetal loss after laparoscopic procedure. Safety of diagnostic techniques and laparoscopic procedures, surgical tactics and independent risk factors of pregnancy loss are touched in the article.

Aim: To analyze incidence, diagnosis and treatment of complicated appendicitis in pregnant women and to determine the optimal surgical approach., Material and Methods: Retrospective cohort analysis included 338 pregnant women who underwent appendectomy in 2012-2016. Complicated appendicitis (abscess, local or common peritonitis and their combinations) was diagnosed in 22 cases. The main perioperative variables (duration of the disease, time of surgery, length of hospital-stay, incidence of wound complications, etc.), clinical and laboratory symptoms, results of ultrasound diagnosis and pregnancy outcomes were analyzed. Statistical analysis was carried out in Stata 14.2. Fisher's exact test, Mann-Whitney-Wilcoxon's U-test and multivariate regression analysis were used to compare data., Results: The incidence of complicated appendicitis in pregnant women was 6.51%. There are no clinical symptoms which would be significantly more common in complicated appendicitis during pregnancy. Complicated course prolongs surgery and hospital-stay, however duration of postoperative analgesia depends on surgical technique as a rule. There were 27% of laparoscopic interventions that is lower compared with women with uncomplicated appendicitis. The percentage of conversions was higher too., Conclusion: Clinical diagnosis of complicated appendicitis during pregnancy even by using of ultrasound is not satisfactory and requires the involvement of other objective methods, such as MRI. Laparoscopic intervention is not contraindicated in pregnant women with complicated appendicitis and determine better treatment outcomes than open surgery.

Aim: To evaluate early and long-term outcomes of ONSTEP procedure including their comparison with those of Liechtenstein hernia repair., Material and Methods: The study consists of 2 parts - retrospective and prospective. There were 472 patients in retrospective part. Prospective analysis included 30 patients after ONSTEP hernia repair and 30 patients after Liechtenstein procedure., Results: Postoperative complications and chronic pain syndrome occurred in 2.9% and 0.4% of cases after ONSTEP surgery, respectively. Moreover, ONSTEP procedure was followed by 2 cases or recurrence. There were no any significant differences between ONSTEP and Liechtenstein procedures., Conclusion: ONSTEP technique is highly effective and safe procedure that can be used in inguinal hernia management.

The toxic effect of Al 2 O 3 , SiО 2 and ZrО 2 nanoparticles on red blood cells of Wistar rats was studied in vitro using the atomic force microscopy and the fluorescence analysis. Transformation of discocytes into echinocytes and spherocytes caused by the metal oxide nanoparticles was revealed. It was shown that only extremely high concentration of the nanoparticles (2mg/ml) allows correct estimating of their effect on the cell morphology. Besides, it was found out that the microviscosity changes of red blood cell membranes treated with nanoparticles began long before morphological modifications of the cells. On the contrary, the negatively charged ZrO 2 and SiO 2 nanoparticles did not affect ghost microviscosity up to concentrations of 1μg/ml and 0.1mg/ml, correspondingly. In its turn, the positively charged Al 2 O 3 nanoparticles induced structural changes in the lipid bilayer of the red blood cells already at a concentration of 0.05μg/ml. A decrease in microviscosity of the erythrocyte ghosts treated with Al 2 O 3 and SiO 2 nanoparticles was shown. It was detected that the interaction of ZrO 2 nanoparticles with the cells led to an increase in the membrane microviscosity and cracking of swollen erythrocytes., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Aim: To compare conventional and laparoscopic appendectomy in pregnant women., Material and Methods: The study included 86 patients with acute appendicitis who were surgically treated. In group 1 (42 women) laparoscopic approach was used, in group 2 (44 patients) - laparotomy., Results: Postoperative complications were observed in 2 (4.8%) and 3 (6.8%) patients in groups 1 and 2 respectively. All complications related to Clavien-Dindo class I-II. There were no premature births and abortions in laparoscopy group. In case of conventional surgery premature births and abortions were observed in 2 (4.5%) and 1 (2.27%) observations respectively. Other women had timely childbirth in terms of 36-41 weeks., Conclusion: Risk of delay exceeds risk of vain appendectomy. All pregnant women with acute appendicitis should be examined by obstetrician-gynaecologist, surgeon, urologist, anesthesiologist. If acute appendicitis can not be excluded based on clinical data the patient should be operated. Diagnostic laparoscopy and laparoscopic appendectomy are advisable in case of pregnancy up to 24 weeks. Woman should be under observation of obstetrician-gynaecologist in perioperative period to prevent premature birth and abortion.

This study enrolled 202 patients with diabetes mellitus and coronary heart disease residing in the Far North. They were selected from 8753 subjects included in the Registry of performed coronary angiographies. The control group contained 196 patients with CHD and DM2 residing in the south of Tyumen region. 76 (19%) patients had normal structural and functional characteristics of LV (LVMM = < N and LVRWT < 0.45), in 322 (81%) these characteristics were pathologically changed (eccentric and concentric LV hypertrophy, concentric LV remodeling). Groups 1 and 2 included 79.2 and 68.4% men respectively p = 0.014) of mean age 53.9 +/- 0.45 and 58.1 +/- 0.51 p < 0.001) having LV diameter 26.2 +/- 0.2 mm and 25.5 +/- 0.2 mm (p = 0.012). Other echocardiographic parameters, occurrence of asymmetric myocardial hypertrophy, and distribution of the patients by the types of LV geometric models were not significantly different. Odd ratios for the patients with pathological LV morphology revealed no dependence of LV remodeling on the site of residence. The structural and functional changes in myocardium of the patients residing in the North and South of Tyumen region were comparable in terms of severity. It is concluded that DM is a powerful factor influencing myocardial remodeling to the extent that masks even the effects of extreme ("northern") environmental conditions.

Mechanisms of nanocrystals of quartz and corundum interaction with erythrocyte membranes were studied by means of atomic force microscopy and fluorescence analysis. It was shown that the hydrophobic, chemically inert nanocrystals with the size larger than the critical value (20-25 nm) can bind to erythrocyte membranes, while not causing her harm. If the size of the nanocrystals is less than 15 nm, they can penetrate into the lipid bilayer membranes. This decreases their microviscosity, the pores appear, which leads to cell lysis. A thermodynamic explication of the critical size of the nanocrystals is given.

Rheodentography (RDG) was used for the study of functional status (vasodilatation or vasoconstriction) of pulp vessels before and after making preparation of hard dental tissues of different volumes as the treatment of partial loss of teeth with metal ceramic crowns. 57 patients were divided into 2 groups--with reduced tone of peripheral vessels (27.2% of the all examined patients) and increased tone of peripheral vessels (72.8%). RDG was registered before the teeth preparation, during 1st week after preparation and also 2, 3 and 4 weeks after preparation when the regular stage of metal ceramic construction making was delivered. All in all 228 RDG were registered, they were estimated visually and quantitatively by amplitude-temporal indices. Differentiated approach was recommended to prosthetic treatment of partial loss of teeth with the help of metal ceramic constructions, demanding deep preparation of hard dental tissues in patients with clinically healthy periodontal tissues having reduced and increased tones of peripheral vessels and in patients with parodontitis.

Little information currently exists regarding the small-scale spatial variability of Chernobyl radiocaesium fallout and associated inventories. This contribution reports the results of a study of the variability of 137Cs inventories within the 2.18-km2 Lapki balka catchment located near Tula in central Russia. The local area was characterized by 137Cs inventories in excess of 200 kBq m-2 immediately after the Chernobyl accident and pre-existing bomb-derived inventories can be ignored in view of their very low magnitude. Field sampling and measurements included both collection of soil cores for subsequent laboratory analysis and in situ field measurements using a CORAD portable detector. The results obtained show evidence of a systematic south-north increase in the reference inventory across the basin, which must be taken into account when interpreting subsequent radiocaesium redistribution within the basin. Random spatial variability of 137Cs inventories of a similar magnitude to that reported for bomb-derived fallout was also documented. The extent of random spatial variability varied between different geomorphological units. Maximum variability, with coefficients of variation up to 20%, was associated with areas of sediment accumulation within the balka bottoms. Substantial variability (cv. typically ca. 15%) was found within flat cultivated areas and undisturbed areas both on the interfluves and on the balka sides, all of which could serve as reference sites. Minimum variability (cv. typically ca. 12%) was associated with the cultivated slopes with no evidence of sediment accumulation.

Results of clinical application of method of non-contact periorbital electrostimulation in 6 groups of neurologic patients (total number-246) with optic nerve pathology of different origin (post-traumatic, hypertensive, inflammatory) are summarized. Analysis of interdependence between positive results and severity of visual disorders, type of the disease, responsible for partial atrophy of optic nerve, was performed. This method of restoration of vision in investigated patients proved to be effective both in hospitals and outpatient departments.

An investigation of the posterior tibial vascular plexus has established certain specific features of its structure both in normality and in patients with postthrombotic disease. The alterations found require an individual approach to choice of surgical measures which is finally determined intraoperatively. At the present time surgical interventions on the posterior tibial veins in patients with postthrombotic disease are thought to be of three types: extended resection, extravasal correction and plasty of the posterior tibial veins.

A new method of rehabilitation of damaged visual nerves has been tested during clinical physiological investigations in 45 patients with pathological opticochiasmal brain tumor, inflammation and trauma. The essence of the new method was in implanting the electrode into the nerve when the patient was operated on for the pathological formation and in directly stimulating the nerves for 2 or 3 postoperational weeks. Effectiveness of electrical stimulation was increased by direct recording of the electroneurogram as well as by the results of ophthalmological observations. Considerable improvement of vision was observed in 75%, and in 25% of these cases the vision was found to actually normalize. Even in cases of total blindness, vision was partially rehabilitated in 8 of 10 cases. Direct electrophysiological investigation of the visual nerve potentials enabled us to objectively estimate their functional state, predict the probability of visual rehabilitation as well as increase the efficiency of therapy. Neurophysiological mechanisms of visual rehabilitation under the influence of electrical stimulation of the visual nerves are discussed.

The data are presented on the content of nitrosamines in meat products prepared according to traditional technology versus the use of water-soluble vitamins and their complex. It is shown that the enrichment of sausage products and canned meat with thiamine, riboflavin, nicotinamide and ascorbic acid is conducive to better hygienic parameters of the products, with lower content of nitrosamines (from 29.4 to 72.6%) as compared to meat products prepared according to the traditional technology.