The aim of the study was to develop a method for assessing the risk of severity of the novel coronavirus infection COVID-19 in patients with chronic hepatitis C depending on the severity of liver fibrosis.

Object and methods. The results of laboratory data of patients with COVID-19 and chronic hepatitis C (n = 147) were analyzed. According to the severity of liver fibrosis, patients with COVID-19 with chronic hepati­tis C were divided into 3 subgroups: mild fibrosis (F1), moderate fibrosis (F2), severe fibrosis (F3). In blood serum, the parameters of total and biochemical (C-reactive protein, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, gamma-globulins, ferritin) blood tests, lipid profile (high-density lipoprotein cholesterol, triglycerides, apolipoprotein A1, apolipoprotein B), hemostasis (fibrinogen, activated partial thromboplastin time), cytokines (interleukin-2, tumor necrosis factor-а). All parameters were assessed in the acute period, depending on the severity of COVID-19 and the stage of liver fibrosis.

Outcomes. Computer program for predicting the severi­ty of COVID-19 in patients with chronic hepatitis C, depending on the stage of liver fibrosis, can be introduced into clinical practice for managing patients in the certain group.

Plastination is a modern and technological method for producing an anatomical macroscopic specimen, which allows preserving the structural integrity of the material under study. The purpose of the study is to study and analyze modern scientific literature on plastination technology and identify the general stages of the process being studied. For the work, a selection of modern scientific literature was carried out, its analysis and systematization of the data obtained. As a result of the analysis, the general stages of the technological process were identified, as well as the features of the methods used by various authors. The influence of technology on the quality of the produced anatomical macro­preparation was revealed.

The cardiovascular system is one of the key systems of the body, which determines the boundaries of a person's physical and mental performance and ensures the adaptation of students' bodies to the educational process. At the same time, various factors can cause tension in students adaptation mechanisms, one of which may be the period of the examination session.

Purpose: to identify differences in the perfor­mance of the cardiovascular system and psychophysiological parameters during the examination session and during seminar classes among medical students of the second year of study.

Object and methods: The study was conducted on 22 second-year students of both sexes. The subjects heart rate and blood pressure were studied and the values of the index of functional changes, adaptive potential and Robinson's index were calculated. The psychoemotional component was assessed according to the results of the Spielberger-Hanin test, the Guilford test and work efficiency, which was calculated based on the time spent working with Schulte tables.

Results: indicators of the cardiovascular system showed an increase in the tension of adaptation processes during seminar classes, compared with the period of the examination session, for example, the IFC values statistically significant changed from 2.12±0.09 to 2.25±0.07 (p<0.05 ). At the same time, there was a tendency to in­crease situational anxiety and a significant increase in the time spent working with Schulte tables from 34.05±2.73 to 44.01±3.1 8 (p<0.05).

Con­clusion: the data obtained allow us to make an assumption about the stress in the adaptation mechanisms of second-year medical students that arise regardless of the examination session, which indicates the need to continue the study in order to identify stress factors.

Relevance. Modern surgery is characterized by the use of various technical means to perform classical surgical techniques - separation and connection of tissues, hemostasis. The study of the applicability of new surgical devices and the search for technological techniques are an important task.

The aim of the study: to evaluate the capabilities of the developed device based on microwave energy for hemostatic coagula­tion of resection surfaces of parenchymal organs.

Materials and methods. The method is based on the principle of converting microwave energy into heat when it is absorbed in biological tissue. The choice of the microwave range is due to the higher efficiency of power supply to the heat­ing area. Based on the prototype of a medical microwave complex developed in 2011 for thermal effects on biological tissues (RF Patent 2481080. 2011), a prototype of a microwave coagulator for working with parenchymal organs was created. The device was tested on the paren­chymal organs of large laboratory animals under conditions of preserved and switched off blood flow in various energy supply modes. Tissue samples from coagulated lesions were studied histologically.

Results. At the site of exposure of the applicator-coagulator to the parenchymal organ, a zone of coagulation changes appears. A clear dependence of the size of coagulation necrosis on the time and power of exposure was noted. When the blood flow is turned off, the necessary stable hemostasis is achieved by shorter exposure time of the coagulator antenna on the surface of the organ.

Conclusions. The most effective and reliable hemostasis is achieved on the liver parenchyma. The use of temporary vascular isolation, especially on the kidneys and spleen, involves a single use of microwave energy to stop bleeding. By changing the power and duration of exposure, it is possible to dose the thermal load on biological tissue with great precision. This adjustment allows you to select the operating mode for each specific case. The obtained results of the experiment of the described system during surgery for the purpose of hemostasis in parenchymal bleeding.

Relevance. Tension-free herniolasty of the anterior abdominal wall is currently the accepted standard for large ventral hernia repairing. The implementation of this approach has been marked by a significant improvement in treatment outcomes. The issues of improving the quality of life of patients after surgery and their effective rehabilitation through the application of the optimal technique of tension-free hernioplasty are now at the forefront.

Objective. To compare the immediate and long-term results of treatment of patients with large postoperative midline ven­tral hernias using anterior and posterior techniques of separation of abdominal wall components.

Object and methods. 114 patients with large postoperative midline ventral hernias were divided into two groups: the patients of the first group (38 patients) underwent hernioplasty using the anterior separation technique, and the patients of the second group (76 patients) - posterior separation. We evaluated the immediate (complica­tions in the area of surgery, duration of surgical wound drainage and duration of hospitalization) and long-term (functional restoration of the abdominal wall) results of treatment with subsequent comparative analysis of data between the groups using descriptive statistics methods.

Results. The present study is the first to compare the immediate and long-term results of using anterior and posterior techniques for separation of anterior abdominal wall components during surgery for midline ventral hernias. It was found that both variants demonstrate good immediate and long-term results in the treatment of patients with median postoperative ventral hernias of large size. At the same time, the anterior separa­tion technique is accompanied by a significantly higher number of complications and, accordingly, is characterized by a higher risk of their de­velopment, as well as requires a longer stay of the patient in the hospital.

Relevance. In the Republic of Tajikistan, in recent years there has been a steady increase in cardiovascular diseases. In this regard, special attention is paid to coronary heart disease with its various manifestations, which can often cause permanent disability, even death. In recent decades, there has been great interest among research scientists in studying the functioning of the endothelium in various forms of coronary heart disease, as well as in individuals with post-infarction cardiosclerosis as a complication of coronary heart disease. Despite the large number of studies in this area, the role and relationship of some sensitive markers of endothelial dysfunction with the clinical course of various forms of coronary heart disease have not yet been determined. That is why its detailed study is of unconditional clinical interest and provides the opportunity for a deep understanding of its theoretical aspects. Purpose of the study: to study risk factors for cardiovascular diseases and mark­ers of endothelial dysfunction in patients with stable angina pectoris in comparison with patients with post-infarction cardiosclerosis, i.e. previous myocardial infarction.

Object and methods. Of 60 patients with various forms of coronary heart disease, whose average age was 62.6 ± 3.5 years, and 20 practically healthy individuals of the same age who made up the control group, three groups were formed: Group I (n = 20) included respondents without coronary heart disease; Group II (n = 30) included patients with stable angina pectoris of functional class II and III; Group III (n = 30) included patients who were diagnosed with post-infarction cardiosclerosis, i.e. previously suffered a myocardial infarction. Endothelial cell dysfunction was detected by determining desquamated endothelial cells, as well as by the activity of von Willebrand factor and the level of homocysteine in the blood plasma.

Results. In the examined patients, risk factors for coronary heart disease in the form of arterial hypertension, physical inactivity and obesity were observed with greater frequency in persons with stable angina pectoris of functional class II, in contrast to those with functional class III. Patients with stable angina pectoris of functional class III all had chronic heart failure of varying severity (100%). Most patients had at least three risk factors for coronary heart disease. All persons with post-infarction cardiosclerosis had risk factors for coro­nary heart disease, while arterial hypertension was detected in 100%. Based on the indicators of endothelial dysfunction, it can be said that individuals in group III have a more severe functional and morphological condition (increased homocysteine levels, von Willebrand factor activity and the number of desquamated endothelial cells) compared to group II (p < 0.001).

Conclusion. In all forms of coronary heart disease (stable exertional angina of functional class II, III and post-infarction cardiosclerosis), the content of desquamated endothelial cells in the blood serum, the activity of von Willebrand factor and homocysteine are increased. A positive correlation was established between the level of desquamated endothelial cells and the level of homocysteine, von Willebrand factor, fibrinogen and platelets. After complex therapy of patients with various forms of coronary heart disease, the functional state of the endothelium improves (decrease in the level of desquamated endothelial cells, ho­mocysteine, von Willebrand factor).

Relevance. Proximal humerus fractures account for up to 75 % of all humerus fractures in patients over 60 years of age. The number of such patients is constantly growing, but there is no consensus on the treatment of this injury.

Target. To determine the effectiveness of using platelet-rich lysate in patients with proximal humerus fractures.

Object and methods. A randomized prospective study was conducted. All operated patients (n = 34) were divided into 3 groups. The first group (main 1) included patients who were administered platelet-rich plasma lysate at the end of surgery – 13 patients. The second (main 2) included patients who used platelet-rich plasma on the 14^th day from the moment of surgery. The third (comparison group) included patients who didn`t use platelet-rich plasma lysate. To objectify the effect of platelet-rich plasma used the ultrasound method of research.

Results. An intergroup comparison at different times after surgery showed that in the Main 1 group, in which PRP was started intraoperatively, the relative thickness of the supraspinatus muscle on the side of the operation was significantly lower than in other groups. In a pairwise comparison in the group of patients without PRP and in patients of the 2nd main group (who were administered PRP n the 14^th day), the relative thickness of the supraspinatus muscle on the side of surgery after 1 month and after 1,5–2,5 months didn`t differ significantly from surgery.

Conclusions. Intraoperative use of platelet-rich plasma can reduce inflammatory changes in the tendons of the supraspinatus and subscapularis muscles, which is reliably confirmed by ultrasound data. 

In the last 30-40 years, there has been a trend in the incidence of cholelithiasis, which, in turn, is often complicated by the development of papillostenosis of various degrees requiring surgical correction. Currently, it is widely used in the diagnosis and treatment of papillostenosis: retrograde choledochopancreatography and endoscopic papillosphincterotomy, but these types of surgical correction of the pathology of large duodenal papilla have a number of disadvantages. In this connection, antegrade choledochoscopy with subsequent augmentation is an option for the diagnosis and correction of papillostenosis narrowing.

Aim: of the study is to study domestic and foreign literature on methods of diagnosis and treatment of papillostenosis. To conduct a comparative analysis of the instrumental methods presented in practice, to evaluate the effectiveness of endoscopic antegrade choledochoscopy in papillostenosis.

Materials and methods. 31 case histories of a patient who was hospitalized in the Department of Surgery of the Hospital No. 18 from 2013 to 2022 with papilla stenosis complicated by mechanical jaundice, who underwent followed by papillaa ugmentation, were analyzed. A narrowing of the lumen of the papilla of less than 2 mm was considered an indication for antegrade choledochoscopy with buging. The postoperative period in 100 % of patients proceeded without peculiarities. The number of bed-days of hospital stay is 4-6 days, discharged with improvement.Of 100 % of patients - 3.2 % (1 patient) – had a history of papilla restenosis after undergoing laparoscopic cholecystectomy, antegrade choledoscopy and augmentation (4.5 years after the first intervention), he underwent retrograde choledochopancreatography and endoscopic papillosphincterotomy.

Conclusion. As presented for 10 years of experience in the use of antegrade choledochoscopy with the bougie of papilla in laparoscopic cholecystectomy, this technique for the diagnosis and treatment of papillostenosis has a large 5-year effectiveness (96.8 %), sensitivity, both due to the optical component of diagnosis and due to the objective component – bougie. In this connection, this method can be used in the practice of a surgeon.

The clinical case is presented to demonstrate the importance of differential diagnosis of cerebral circulation disorders in patients with acute or chronic toxic effects of psychoactive substances. In the presented observation, a 50-year-old patient was taken to the N.V. Sklifosovsky Research Institute of SP with depression of the level of wakefulness to deep deafness, denies the fact of using psychoactive substances when collecting anamnesis, bilateral myosis, diffuse decrease in tone in all extremities. Computed angiotomography of the brain, transcranial dopplerography, magnetic resonance imaging of the brain, electroencephalography were performed – without obvious diagnostic findings. During a detailed examination in a neurological clinic, no data were obtained for a violation of cerebral circulation, a chemical and toxicological examination of urine and blood was performed, fentanyl was detected in biological media. Based on the literature data, however, damage to the nervous system usually occurs due to chronic intoxication and it is not always possible to detect psychoactive substances in biological environments. Due to respiratory depression, the patient was intubated and was on artificial ventilation for 72 hours until spontaneous respiration was restored. After repeated demand, the patient admitted the fact of using fentanyl allegedly to relieve pain, after which he refused further treatment. The conclusion is the need for a chemical and toxicological study of biological media in the case of a violation of consciousness of unclear genesis, however, damage to the nervous system usually occurs due to chronic intoxication and it is not always possible to detect psychoactive substances in biological media.

Introduction. Fractures of the proximal part of the femur are one of the most common fractures, especially for elderly patients. Most of them are low in energy and occur on the background of osteoporosis. Femoral neck fractures are one of the most frequent causes of hospitalization of patients in the trauma department. The treatment of fractures of the proximal part of the femur must be surgical. During fractures of the trochanteric region, there is a tendency to have a good consolidation of the internal fixation thanks to a rich vascularization of this region. The success rate of consolidation of femoral neck fractures is lower, which imposes the need for the use of the prosthesis. However, it is not always possible to carry out a major traumatic operation due to the presence of a serious somatic pathology of the patient. The need to delay the surgical intervention may be the cause of the development of hypostatic complications and the absence of fracture consolidation, which, in turn, may aggravate the patient's condition and provoke the development of irreversible complications. In addition, the absence of fixation of the fracture induces the presence of the syndrome of strong pain that makes the quality of life of the patient worse. With the aim of rapid activation of patients with severe pathology, it has been proposed to use a minimally invasive means of percutaneous femoral neck internal fixation using pins without incising the skin and without open repositioning.

The aim of the study: to evaluate the results of therapy obtained using the method of percutaneous minimally invasive osteosynthesis in patients with fractures of the femur in the proximal section.

Materials and methods. According to the developed and presented method, therapeutic manipulations were performed for a fracture of the femur in the proximal section in 16 senile and long-livers patients, in whom extensive surgery was contraindicated or there was a need to delay it.

Results. The treatment performed avoided thromboembolic complications, hypostatic complications in 94 %of cases and intraoperative delirium.

Conclusion. The application of early fracture fixation increases the success rate of fracture consolidation compared to conservative treatment, which activates the patient, reduces pain and improves the quality of his life.

Relevance. To date, all pathognomonic clinical and radiological signs have not been identified for any disease manifested in the form of cavities in the lung, which leads to diagnostic errors, the frequency of which varies from 19 to 93.7% in various pathological processes in the lungs. The clinical course of most forms of cavities can often be complicated by the development of respiratory failure and/or pulmonary hemoptysis/bleeding.

Aim: to demonstrate the result of surgical treatment of a patient with a cavity formation of an operated lung complicated by recurrent pulmonary hemoptysis.

Object and methods. A clinical case of successful application of extrapleural pneumolysis with the installation of a silicone implant from the operated lung as a method of eliminating sanitized cavities is described.

Clinical case description. Patient M., 54 years old, long-term follow-up for rheumatoid arthritis, receiving courses of immunosuppressive therapy, noted the appearance of cough, a single episode of hemoptysis. Pulmonary tuberculosis was excluded based on the clinical and radiological picture. Due to the recurrence of hemoptysis, an upper lobectomy was performed on the left. In the histological examination of the surgical material: the morphological picture is characteristic of bronchiectasis of the lung with the development of nonspecific purulent granulomatous inflammation. Due to repeated episodes of hemoptysis, extrapleural pneumolysis was performed with the installation of a silicone implant, after which the episodes were not repeated.

Conclusion. The EPSI collapsosurgical method made it possible to preserve the patient's functional reserves as much as possible and compress the lung cavity formation, which confirms its high effectiveness. 

Using the example of clinical observation, the features of withdrawal from shock, the possibility of using hemofiltration in the early stages after severe combined trauma complicated by blood loss to soft tissues, which made it possible to avoid the development of infectious complications, are shown. 

Introduction. There is an annual increasing of kidney transplantion all over the world. The number of recipients with hyperhomocysteinemia before and after the operation is also increasing, which increases the risk of cardiovascular complications, graft loss and patients’ death.

Materials and methods. A 28-year-old patient with terminal chronic renal desiase in the outcome of chronic glomerulonephritis had underwent an allogeneic kidney transplant from a 52-year-old donor, with confirmed brain death in the outcome of acute hemorrhagic cerebral circulatory disorders.

Results. The early postoperative period has complicated by thrombosis.

Conclusion. The study of blood homocysteine levels is mandatory when examining patients for kidney transplantation.

Relevance. The study of pigmented melanoma of the skin is an urgent problem today, because this pathology has an aggressive course, frequent localization on the skin, rare occurrence – no more than 2-8% among other malignant neoplasms of the skin, while it is difficult to diagnose clinically, pathohistologically.

The purpose of the study: to study the clinical, dermatoscopic and pathomorphological diagnosis of pigmented and pigmented melanoma of the skin. As tasks, the possibilities of diagnosing pigmented and pigmentless melanoma of the skin at the stage of consultation, as well as the features of the use of light microscopy and immunohistochemical examination by pathologists were studied.

Material and technical base: Delta Heine 20 dermatoscope, Carl Zeiss Axio Scope A2 light microscope, evaluation of results according to clinical recommendations. As a result of the study, it was revealed that the diagnosis of pigmented, unlike pigmented, melanoma of the skin is difficult due to the lack of characteristic signs. It was concluded that it is advisable to use digital dermatoscopy at the clinical stage; an immunohistochemical examination should be used by a pathologist; if there is doubt about the goodness of the process, an incisional biopsy of the neoplasm with a pathohistological examination is required. 

Background. Chronic liver disease is one of the most common diseases. In many countries, liver disease is among the top five causes of death. The liver is one of the main organs responsible for basic metabolic functions, protein and hormone synthesis, detoxification and waste elimination. In chronic liver disease, there is a continuous process of inflammation, destruction and regeneration, ultimately leading to severe dysfunction, causing the development of fibrosis and cirrhosis. The main task of the radiation diagnosis of chronic liver disease is the development and introduction into clinical practice of new noninvasive biomarkers for a comprehensive assessment of the structure of the liver parenchyma in order to choose further treatment tactics.

Aim a comprehensive analysis of the modern possibilities of radiation imaging methods in the diagnosis of chronic liver disease.

Materials and methods. The analysis of 107 modern publications of domestic and foreign literature devoted to the diagnosis of chronic liver disease  of various etiologies was carried out.

Conclusion. the review reflects the most common modern and promising methods of radiodiagnosis for chronic liver disease, which in most cases make it possible to avoid invasive interventions in the process of establishing a diagnosis and monitoring the response to treatment

Background. Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease, which is characterized by the inevitable disability of patients in the long term, which determines the relevance of this problem. Currently, active improvements are being made in the methods of diagnosing multiple sclerosis, which include the use of the central vein sign in magnetic resonance imaging (MRI) as a neuroimaging biomarker of MS with high sensitivity and specificity.

Aim of study. Determination of the possibility of assessing the central vein sign (CVS) according to MRI data as a potential diagnostic biomarker of MS.

Object and methods. An open single-center prospective study of brain MR data was conducted in 55 patients with a verified diagnosis of MS (EDSS 1.0-6.5) aged 19 to 72 years. MR-images were obtained on a tomograph with a magnetic field induction force of 3.0 T. Patients underwent MRI of the brain according to the standard protocol: T2-VI, FLAIR, T1-VI (before and after administration of contrast agent), SWI. A comprehensive statistical analysis and evaluation of the obtained MRI data was performed using the Statistica 12 program.

Result. During the evaluation of MR-tomograms, all patients with a verified diagnosis in the foci of MS were found to have CVS. In 14.5 % of patients, CVS was detected in 10-30 % of foci, in 61.8 % of patients in 30-60 %, in 23.6 % of patients, from 60 to 95 % was detected. Accordingly, 52.7 % of patients overcame the threshold value of 45 % required for the differential diagnosis of MS from other conditions.

Conclusion. The use of CVS in MRI helps to solve the problem of differential diagnosis of MS from other demyelinating diseases when using its threshold criterion – the percentage of foci containing central veins.

Allogeneic tendon grafts are seriously demand in knee joint plastic surgery. The novel method of tendon cryopreservation, including sterilization with supercritical carbon dioxide, was developed in N.V. Sklifosovsky Research Institute for Emergency Cryopreserved tendons retain their normal fiber structure without significant loss of mechanical properties. At the next stage it was necessary to evaluate cryopreserved tendons′ integration inside bone canal in experimental animals.

The aim of study. To evaluate morphologic changes of autologous and allogeneic tendons inside the femur in rats and to determine the effect of tendon transplantation on the physical activity.

Material and methods. The study was conducted on white inbreed male rats. Three groups of animals were formed: the control group (animals without tendon transplantation), the 1st experimental group – animals with autologous tendon transplantation, the 2nd experimental group – animals with allogeneic tendon transplantation. In animals of the experimental groups the through channel was formed in the distal metaepiphysis of the femur and a tail tendon graft 0.5 x 0.1 cm was placed there. To assess the physical activity of the animals, we studied maximum distance that the animals could run 3 and 6 weeks after transplantation was determined, using treadmill test. The graft structure was evaluated on histological preparations in transmitted light, stained with hematoxylin-eosin and Van Gieson′s stain. To assess the preservation of collagen fibers we checked the autofluorescence intensity of collagen.

Results. According to the treadmill test, the distance run by the animals of both experimental groups did not significantly differ from the values in the control group. Histological analysis after 3 weeks in both experimental groups revealed signs of fibers′ decomposition in the absence of inflammatory infiltration and maintaining close contact with bone trabeculae. The autofluorescence intensity of the collagen fibers in grafts corresponded to normal or was close to normal. After 6 weeks, the animals of both experimental groups revealed areas of graft fusion with their own bone, Sharpe fibers were actively formed. In both groups, numerous small vessels with diameters up to 10 microns were detected in the area of tendon-bone contact. Infiltration of grafts by inflammatory cells was absent or very insignificant, active migration of fibroblasts to the tendon area was also not observed. In both groups, tendon grafts had areas where fiber decompactization was observed.  In the area of contact with the bone, the autofluorescence of tendon fibers was sharply increased, which indicates the chemical cleavage of collagen. At 3 and 6 weeks after transplantation the effect of fixation (integration) of the tendon with bone tissue was observed in both experimental groups.

Conclusions. Allogeneic tendon grafts did not cause a pronounced inflammatory or immune reaction in experimental animals. 6 weeks after transplantation of autologous and allogeneic tendons, the integration of grafts inside the femoral canal was observed. Cryopreserved allogeneic tendons were able to integrate into the body's own tissues without pronounced structural and functional disorders. According to the treadmill test, the distance covered by the animals of both experimental groups did not differ statistically significantly from the values in the control group (without tendon transplantation) after 3 and 6 weeks

Relevance: Arterial hypertension (HTN) in kidney transplant recipients is a major risk factor for cardiovascular diseases, graft rejection and premature death. In the post-transplant period in 80% of cases persistent or refractory arterial hypertension develops which is difficult to correct with conventional drug therapy. Treatment difficulties include the ineffectiveness of many first-line drugs and the fact that the most common immunosuppressive drugs (cyclosporine, tacrolimus and methylprednisolone) contribute to the development of hypertension. This type of hypertension represents a significant problem in clinical practice due to the complexity of treatment and high mortality. The need to study the treatment of post-transplant hypertension is due not only to its clinical significance, but also to the potential opportunity to improve treatment results and life expectancy of kidney transplant recipients.

Objective: to study the genesis, risk factors, pathophysiology, diagnosis and treatment of posttransplant hypertension.

Materials and methods: 37 literary sources were analyzed.

Conclusions: High blood pressure exposes the recipient of a kidney transplant to the risk of CVD and mortality as well as increased systemic hypertension which can be a cause and a consequence of renal pathology. Hypertension is a modifiable risk factor contributing to the progression of renal failure. There is no any single treatment algorithm. It is often necessary to use several antihypertensive drugs to achieve the target blood pressure. 

Introduction. Hepatocellular cancer is the most frequent primary malignant neoplasm of the liver, developing against the background of viral hepatitis, alcohol abuse, metabolic disorders, cirrhosis. Most often hepatocellular cancer is diagnosed at late stages of the disease, when patients are no longer subject to specific treatment. The priority method of treatment of early stages remains surgical. In the absence of cirrhosis or with compensated cirrhosis the best option is liver resection, in other cases orthotopic liver transplantation is performed. However, when hepatocellular cancer is diagnosed, most patients fall outside the Milan criteria, and the bridge to orthotopic liver transplantation is down-stage therapy. Bridge therapy is used to treat hepatocellular cancer while awaiting liver transplantation and aims to prevent stage progression. The probability of progression of hepatocellular cancer after orthotopic liver transplantation within the first two years is about 75% and about 10% is detected after the fourth year. Progression of hepatocellular cancer remains the main factor limiting the life expectancy of patients after orthotopic liver transplantation.

The aim of the study: to evaluate the results of antitumor treatment of patients with hepatocellular cancer progression after liver transplantation.

Materials and methods. We evaluated the results of treatment of 50 patients with hepatocellular cancer progression after orthotopic liver transplantation, who were treated on the basis of FGBU NMI Center of Oncology named after N.N. Blokhin. N.N. Blokhin Oncology Center in the period from 2009 to 2020. We analyzed and evaluated overall and recurrence-free survival depending on the bridge therapy, type of treatment, presence of vascular invasion and portal vein thrombosis.

Results. According to the results of bridge therapy, hepatocellular cancer stage progression was observed in 9 patients, stabilization - in 17 patients, partial/complete response – in 9 patients. The median recurrence-free survival of patients who received bridge therapy and down-stage therapy was 23.6 months; among patients who did not, it was 35.6 months. The median overall survival with surgical treatment was 79.8 months, whereas with radiation therapy it was 17.2 months. 

Conclusions. In the studied group of patients the treatment was tolerated satisfactorily. Optimization of immunosuppression protocol and modification of dose regimens of systemic therapy is considered as a condition for treatment, which leads to improvement of long-term treatment results (overall and relapse-free survival). 

Relevance. The durability of a splint depends on a number of factors: the level of oral hygiene, the degree of tooth mobility, the presence of occlusal trauma, and the strength of adhesion of the splint-dental interface. In turn, the issues of adhesion are inextricably linked to the anatomical features of the structure of hard tissue, particularly enamel. The correct execution of the cleaning, removal of the aprismatic layer and acid etching steps in the fabrication of an extracoronal splint determines the quality of adhesion at the tire-tooth interface.

The aim of the study is to study the enamel surface structure in preparation for extracoronal splinting of teeth.

Material and research methods. The 40 teeth were divided into 4 groups depending on the chosen method of preparation for fixation of the reinforcement structure in the extracoronal splint: brushing with paste, treatment with air-abrasive and ultrasonic methods, preparation with a fine-dispersed diamond boron.

Results of the study. The preparation of enamel surface with fine diamond boron with particle size of 20 µm and acid etching with 37 % orthophosphoric acid determined a uniform character of microstructure, in the full volume the etched areas of enamel prisms amounted to 98.55±0.51 % of the total surface area of the treated enamel.

Conclusion. The preparation of the enamel surface with a fine diamond boron removes the aprismatic layer, ensuring the longevity of the fabricated splint by creating a high-quality "hybrid" layer at the splint-dental interface. 

Introduction: The roles of clinical instructors at the diploma level are lacking despite studies showing clinical instructors are an effective conduit for supporting the transfer of learning needed to address performance gaps in students. Clinical instructors increase the confidence of students in preparation for clinical practice and allow them to reflect on their professional development.

Materials and Methods: A descriptive cross-sectional study was conducted on 400 clinical medicine students attending their clinical placements.

Results: It was established that the core roles of the clinical instructors to clinical medicine students were mentorship to students in the clinical area, demonstrating of the clinical examination, follow-up, and supervising students.

Conclusion: The study concluded that Mentors gave prominence to the needs of the students under their care and helped them manage nervousness during actual clinical practice.

Introduction. Currently, there is a fairly high demand from society for changing approaches to the life of people with disabilities, improving the level and quality of their lives. There is an increase in the number of people with disabilities who need to be assisted when receiving services for assisted living, assisted work and social employment of disabled people in the Russian Federation. The article considers the main methodological approaches to assessing the quality and effectiveness of support measures in the provision of services for assisted living, assisted work and social employment of persons with disabilities.

Aim. The study of indicators of the quality and effectiveness of support measures for the formation of unified approaches in various departments of the support system of the Russian Federation aimed at improving the level of assistance and support to the population.

Materials and methods. Normative legal and methodological documentation, special literature, information systems of federal executive authorities of the subjects of the Russian Federation. Applied general scientific methods (content analysis, analytical, system-structured, comparative) and methodological methods of systematization, comparison, generalization, interpretation, as well as special methods — formal legal, comparative legal.

Results. The main approaches to assessing the quality and effectiveness of support measures may include: availability of receiving support events; compliance with goals and objectives; the economic component (the necessary costs for conducting support activities); competence and professionalism of specialists; satisfaction of recipients (improving the quality of life of recipients). To assess the quality and effectiveness of support measures, the following criteria are highlighted: improving the quality of life of assisted persons, including their physical, psychological and social well-being, improving social adaptation and inclusion of escorted persons in society; the communicative effectiveness of the work of the specialists of the support system, both in a group and individually with each assisted one; сost-effectiveness of support activities, optimization of resource use and reduction of costs for the provision of the support process; аssessment of the satisfaction of the assisted ones and their families with the assistance and support provided; the effectiveness of interdepartmental interaction, co-operation and co-ordination of work between various services and organizations in the support system; assessment of the achievement of targets and tasks in the support system. The score is determined for each criterion separately based on the amount of points received. If the amount is below 55% of the maximum possible, the rating is "unsatisfactory", if from 56 to 85% – "good", above 85% – "excellent". Thus, the introduction of methods for evaluating the effectiveness and quality of support measures will make them more accessible and useful for all categories of the population in need of the Russian Federation.

Discussion. One of the key indicators of the quality and effectiveness of the support system's activities is the availability of support activities for all those in need. It is necessary to ensure equal access to quality support in obtaining social services for all categories of people in need, regardless of their place of residence, family income and other factors. Another important indicator is the effectiveness of the work of the specialists providing support. Training and advanced training of specialists, as well as modern methods of working with assisted ones and their families, will help to increase the effectiveness of assisting activities when receiving social services and improve the results of assistance, in general. Effective implementation of methods and technologies for assessing the quality, accessibility and effectiveness of the support system requires a systematic approach and co-ordination of efforts at various levels, interdepartmental interaction, regulation of legal relations in the support system in the Russian Federation.

Conclusion. The main indicators of the quality and effectiveness of support contribute to providing feedback from both the assisted ones and those in need of support activities, as well as from the specialists of the support system and management structures. This will allow considering the opinions and needs of all participants in the support process, which contributes to the development of a sustainable and adaptive system.