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Theory of interband optical absorption in rectangular quantum well with infinite barriers based on materials with strong nonparabolicity and anisotropy of energy spectra is developed. The numerical calculations for three-dimensional Dirac cadmium arsenide are done. Special attention is paid to the investigation of the effects of energy gap oscillation and “blue shift delay” in this material. Розвинуто теорію іж зонного оптичного поглинання в прямокутних квантових ямах з нескінченними бар’єрами, що базуються на матеріалах з сильно непараболічним анізотропним енергетичним спектром електронів. Числові розрахунки виконано для тривимірного діраківського напівметала – арсеніду кадмію. Особливу увагу приділено дослідженню ефектів осциляції ширини забороненої зони та «запізненню блакитного зсуву» в цьому матеріалі. Развита теория межзонного оптического поглощения в прямоугольных квантовых ямах с бесконечными барьерами, базирующимися на материалах с сильно непараболическим анизотропным спектром электронов. Численные расчеты выполнены для трехмерного дираковского полуметалла – арсенида кадмия. Особенное внимание уделено исследованию эффектов осцилляции ширины запрещенной зоны и «запаздыванию голубого сдвига» в этом материале.

Стаття присвячена дослідженню функції оборони країни. Функції держави встановлюються залежно від основних завдань, які стоять перед ним на тому чи іншому етапі його розвитку. В умовах загострення глобальних проблем людства, порушення світового правопорядку Російською федерацією, що зумовило анексію Криму, проведення АТО в Донецькій і Луганській областях, особливої актуальності набувають проблеми реалізації вищевказаної зовнішньої функції нашої держави. Авторами проаналізовані позиції вчених із зазначеної проблеми, положення законодавства у цій сфері. У статті наголошується, що діяльність держави щодо забезпечення свого захисту має складний зміст і різні цілі. На їх реалізацію спрямовані підготовка та ведення політичної, дипломатичної, інформаційної та економічної боротьби. Невід'ємною складовою частиною цієї діяльності є створення військової організації держави і здійснення керівництва нею. На основі проведених досліджень визначено особливості функції оборони держави та шляхи її реалізації в сучасних умовах. The article deals with one of the external functions of the state – the function of the defense of a country. The functions of the state are set depending on the major objectives facing the state at this or that stage of its development. In the conditions of aggravation of global problems of humanity violation of the international legal order by Russian Federation that caused he annexation of the Crimea, conducting ATO in the Donetsk and Lugansk regions, problems of implementation of the above-mentioned external function of our state have become particularly important and urgent. The authors analyze the scientists’ approaches to the above-mentioned problem and legislative provisions in this area. It has been proved that activities of the state to ensure its protection has a complex meaning and different objectives. Preparation and maintenance of the political, diplomatic, informational and economic struggle are aimed at realization of these objectives. An integral part of this activity is the creation of the state military organization and providing management of it. The authors state that each function of the state is carried out simultaneously in both legal and organizational forms, including the function of defense of a country. The results of the study helped to identify the peculiarities of the function of defense of the state and the ways of its realization in modern conditions.

The authors describe herein a variant of successful palliative treatment of a 73-year-old male patient suffering from an inoperable thoracoabdominal aortic aneurysm accompanied by coronary artery disease, painless myocardial ischaemia, pathological tortuosity of the left internal carotid artery, type 2 diabetes mellitus, and chronic renal insufficiency. The patient was admitted to the Department of Vascular Surgery presenting with critical ischaemia of his left lower limb, complaining of numbness and gnawing pain both at rest and while walking a distance of up to 10-15 metres, demonstrating portions of skin ischaemia up to 2 cm long on the anterior surface of the femoral upper third, clinical signs of a thoracoabdominal aortic aneurysm, the presence of a pulsating formation in the projection of the infrarenal portion of the abdominal aorta measuring 5x6 cm. The diagnosis was made based on the findings of instrumental examination, ultrasonography, multispiral computed tomographic angiography, and coronarography, having confirmed the following: a thoracoabdominal aortic aneurysm, occlusion of the left common artery and anterior iliac artery, coronary artery disease, painless myocardial ischaemia, pathological kinking of the left internal carotid artery, chronic renal insufficiency, and type 2 diabetes mellitus. The first stage of the operation to perform consisted of mammary- coronary bypass grafting of the anterior interventricular artery from the left anterior lateral thoracotomy. Despite certain improvement in the condition of the coronary bed, the patient remained inoperable due to the presence of pronounced multipleorgan pathology and a high risk of lethal complications. Given these circumstances, the second stage of the intervention consisted in performing a palliative operation of subclavian-femoral bypass grafting on the left with a reinforced polytetrafluoroethylene stent graft.

Carotid endarterectomy (CEAE) is currently considered to be one of the most efficient methods of treatment for chronic cerebrovascular insufficiency and prevention of recurrent acute impairments of cerebral blood supply. Methodically, the manipulation concerned is in the majority of cases carried out by one of two most commonly employed techniques, i. e., classical CEAE from the longitudinal arteriotomy with plasty with a synthetic patch, and the so-called eversion CEAE implying removal of an atherosclerotic plaque (ASP) by means of eversion of the internal carotid artery (ICA). Many Russian and foreign authors point out indisputable advantages of eversion CEAE, consisting in a shorter duration of ICA clamping, no need to use synthetic materials, preservation of the anatomical geometry of the bifurcation of the common carotid artery (CCA), a lower incidence rate of restenoses in the remote period. Along with it, eversion CEAE also possesses certain disadvantages consisting in namely complicated revision of the distal intima of the ICA (the zone wherein the ASP is tapering), the necessity of traction by the ASP, which may might lead to its premature detachment, impossibility of ICA eversion distal to the endarterectomy zone and repeat eversion of the already endarterectomised portion of the ICA. Hence, eversion carotid endarterectomy still remains the area of skilled and experienced vascular surgeons, thus giving prerequisites for further levelling its technical disadvantages shortcomings, which was the objective of the present study. The authors describe herein a new specially designed surgical device intended to facilitate the operation of eversion carotid endarterectomy, as well as the technique of application thereof. Based on a comparative example comprising a total of eighty-six eversion carotid endarterectomic procedures performed both with and without the new device, we demonstrated efficiency of using the proposed technique.

Clinical and neuropsychological features of non-dementia cognitive disturbances were studied in 102 patients with atherosclerotic carotid stenosis. Cognitive disturbances were assessed after the carotid endarterectomy (CEAE). Mild cognitive impairment was found in 37 (36,3%) of patients, moderate cognitive impairment was diagnosed in 36 (35,3%)patients. Moderate cognitive impairment was found more often in patients with symptomatic carotid stenosis with structural brain changes confirmed by neuroimaging data and with instable atherosclerotic plaques with the predomination of hypodensity component. It allows to suggest that both the reduction of perfusion and arterio-arterial microemboli may cause cognitive dysfunction in patients with atherosclerotic carotid stenosis. The data on the positive effect of CEAE on cognitive functions have been obtained. The positive changes were more distinct in patients with asymptomatic course of carotid stenosis. However CEAE may have a negative effect on cognitive functions in patients with moderate cognitive impairment of dysmnestic character and symptomatic carotid stenosis.

Described in the article is a case report of successful surgical management of a 50-year-old male patient presenting with a gigantic aneurysm of the right internal carotid artery, pathological tortuosity of the right and left internal carotid arteries, successfully treated by resection of the aneurysm of the right internal carotid artery with autovenous prosthetic repair of the right internal carotid artery.

The present work deals with analysing the outcomes of surgical management carried out in a total of five hundred and sixty-six patients diagnosed as having embologenic thrombosis of the lower-limb deep veins. Of these, 377patients received a cava filter implanted, with the remaining 189 patients being subjected to thrombectomy from the iliac and femoral veins. In nineteen patients, the operation was supplemented by establishing an arteriovenous fistula. The decision of whether or not to perform a surgical intervention in patients presenting with thrombosis of deep veins of the lower extremities was made based on the type and pattern of the thrombus concerned. First of all, such surgery was indicated primarily for those diagnosed with a floating, embolus-hazardous thrombus. Thrombectomy was carried out in the patients with a favourable prognosis of the underlying disease, if activation of the pathological process was possible. Cava filters were implanted to the patients diagnosed as having a recurrent embolism, with an unfavourable prognosis of the course of the underlying disease, as well as to those presenting with a severe concomitant pathology. Ultrasonography-guided control is obligatory at all stages of management.

The article deals with four reports of rarely encountered clinical cases, i. e., a ruptured aneurysm of the abdominal aorta in patients having previously sustained endovascular grafting of the abdominal aorta for the pathology concerned. The incidence rate of such complications we faced for the first time in 2001 has ever since amounted to 1.6 % of the total number of patients with a ruptured aneurysm admitted to our Department over the period form 2001 to 2006 (250 patients). All the patients were emergently operated on, with the lethality rate amounting to 50 % (two of the four patients died). The time having elapsed from the primary operation (endovascular grafting of the abdominal aorta aneurysm) till the rupture ranged from 11 days to 3 years.

Presented herein are the outcomes of managing a total of twenty-six patients suffering from an uncomplicated abdominal aorta aneurysm with a concomitant atherosclerotic lesion of the coronary arteries, referred to our Clinic over the period form 2003 to 2006. Of these, nineteen (70%) patients were diagnosed with the first (symptom-free) stage of cerebral ischaemic disease, and six presented with the second stage [to have endured a transient ischaemic attack (TIA) within the terms from 16 to 3 months prior to admission]. Two patients had residual events of the previously sustained acute cerebral ischaemia (ACI) (stage 4). The current stage ofischaemic cerebral disease was determined according to the classification of A. V. Pokrovskii (1979). The haemodynamically significant stenoses of carotid arteries (over 70%) were revealed in five patients, an aneurysm of the internal carotid artery - in one patient, and eighteen patients were presenting with the degree of carotid arteries stenosis varying from 30 to 60% (of these, in two subjects after previously endured TIA, the plaque was heterogeneous and defined as embolism-threatening). No atherosclerotic lesions of the carotid artery were revealed in two patients, though these patients had previously sustained an AIA with the preserved neurological deficit by the moment of examination. Eight patients underwent reconstruction of the internal carotid arteries. The average age amounted to 64.5 years. Al of the eight operated on patients with a combination of ischaemic cerebral disease and an aneurysm of the abdominal aorta were found to have had no neurological complications either after the first, or after the second operations. The devised algorithm of examination and surgical management for patients presenting with an abdominal aorta aneurysm and a combined lesion of the brachiocephalic arteries made it possible to reduce the rate of neurological complication from 4.3% to 1.3%.

Dominating factor of development of functional mitral insufficiency in patients with ischemic heart disease and dilated cardiomyopathy is deformation of atrioventricular valve leaflets due to traction by chordae apparatus. In patients candidates for left ventricular reconstruction because of its postinfarction aneurism the problem of preexisting or recurrent dysfunction of mitral valve acquires special value as operation itself implies surgical ventricular remodeling and therefore change of mitral valve geometry. Supplementation of the volume of surgical intervention with resection of chordae responsible for impaired coaptation of mitral valve leaflets in some cases appears to be effective and simple method of correction of mitral insufficiency.

Dynamics of lipoprotein oxidation in blood plasma was studied by Cu-induced plasma oxidation in 114 patients with atherosclerosis of lower extremities of various severity with and without ischemic heart disease. Preparedness of plasma lipoproteins to oxidation in patients was higher than in healthy subjects. Degree of oxidizeability increased with increase of severity and extent of atherosclerosis and was highest in patients with atherosclerosis of lower extremities and ischemic heart disease. There were no significant differences between groups of patients with various severity and extent of atherosclerosis in levels of total cholesterol and triglycerides as well as in other parameters of lipid spectrum. Correlation analysis revealed no relationship between age of patients and degree of plasma oxidizeability.

Experience with 150 endovascular stents and endoprostheses including ones of vertebral and carotid arteries (first experience in Russia) is analyzed. Mini-invasive surgery is indicated for patients with isolated arterial lesions (segmental stenosis, short occlusions), changed and hard for surgery parts of vascular system (renal, visceral arteries, branches of aortic arch), restenosis after traditional surgeries and also for patients with severe concomitant diseases. Rate of complications of carotid endovascular stenting was 4,3%. The follow-up ranged from 2 months to 5,5 years. There were no restenoses in the stented zone. Complete absence of complains and regress of neurological symptoms were seen in 89% patients.

Presented herein is a case of vein graft aneurysm formation 16 years after femoropopliteal bypass grafting using the reverse autogenous vein.

The authors present a successful case of simultaneous operation for rectal cancer and abdominal aortic aneurysm.

Between 1998 and 2002, 256 tomographic investigations of the abdominal aorta were performed. Aortic aneurysms were identified in 29 (11.3%) patients. Computed tomographic angiography (CTA) was provided to 16 patients 4 patients were examined by an electron-radiation tomograph, 6 by a spiral tomograph, 6 by a multispiral tomograph, and 13 patients underwent magnetic resonance angiography (MRA), with contrast enforcement. Two- and three-dimensional reconstructions of CT- and MR-angiograms were accomplished using special computerized working stations. Good quality MR- or CT- angiograms were obtained in all the patients examined. Interpretation of the angiograms did not cause noticeable difficulties. None of the patients required conventional contrast angiography. The investigations have demonstrated the benefits of multispiral CTA recognized as the method of choice for the diagnosis of aortic aneurysms. Of the 29 patients with the verified diagnosis of aneurysm of the abdominal aorta, aneurysms in 26 subjects were located in the infrarenal aorta. Of these, 5 patients were identified to have an aneurysm extending to the iliac arteries. In two patients, aneurysms extended to the renal arteries or to the suprarenal segment. A thoracoabdominal aneurysm (type III) was revealed in one patient. Associated aneurysm and occlusive lesions of lower extremity arteries (iliac, femoral) were present in 15 (51.7%) cases. In the majority of cases (89.7%), aneurysms ran an uncomplicated course. The complications encountered by us consisted in incomplete (intramural) rupture (2 patients) and dissection (one patient). 22 patients were operated on. Comparison of the intraoperative revision data with the results of preoperative CT and MR angiography has established that the sensitivity of the tomographic methods for the diagnosis of aneurysms was 95.7% and specificity 99%. With an accuracy of up to 2-3 mm there were determined the size of aneurysms, the distance to the renal arteries, the diameter of the proximal and distal "neck", the extension of aneurysms to the iliac arteries, the presence of occlusive lesions of lower extremity arteries. CT and MR angiography with bolus contrast enforcement are safe and noninvasive methods for the diagnosis of aortic aneurysms. They have the high information content and thus allow to plan surgical (and possibly endovascular) interventions without the use of conventional contrast angiography.

A comparative study of 48 carotid stent grafting and 23 open carotid endarterectomies was carried out. Patients of both groups were comparable by cerebrovascular insufficiency degree and concomitant diseases. General rate of complications after carotid stent grafting (CSG) was 5.1%. There was a small ischemic stroke with right-sided hemiparesis and aphasia in one patient during CSG. Complete regress of the neurological symptoms was seen on the 5th day. In the nearest postoperative period after CSG there was a big ischemic stroke in the territory of MCA in one patient. Rate of complications after open carotid endarterectomy (OCEAE) was 8.7% Transient ischemic attacks were seen in 2 patients in early postoperative period. Paresis of the IX cranial nerves was in one patient. In long-term postoperative period after CSG 2 patients died due to cardiac causes. One patient died 18 months after OCEAE due to ischemic stroke. In long-term period after OCEAE restenosis of the internal carotid artery was seen in 4.5% cases, while there were no restenosis after CSG. It is concluded that CSG is an effective method of treatment of carotid stenosis with lower lethality and postoperative complications rate compared with OCEAE. Indications for CSG are symptomatic stenosis of ICA (60%), asymptomatic stenosis of ICA(70%), two-sided lesions of the carotid arteries, carotid stenosis with lesions of other brachiocephalic arteries, insufficiency of Willis circle.

The problem of surgical treatment of elderly and old patients with critical limb ischemia and severe concomitant diseases is discussed. Surgical bypass from remote vascular beds is the only real possibility of effective care for such patients with the lowest risk. The results of treatment of 90 patients with critical limb ischemia were analyzed. The surgical technique is described in details. Modified methods of proximal anastomosis creation and technology of safe installation of graft into subcutaneous canal in subclavial-femoral bypass, surgical technique in femoral-femoral and ileo-femoral cross-over bypass are also described. Results demonstrate high efficacy of these surgeries and their lower risk. It is concluded that improved surgical technique permits to expand indications for surgery in elderly and old patients and to improve immediate and long-term results.

Treatment of patients with abdominal aortic aneurysms has been analyzed. From 506 patients (265 emergency and 241 elective cases) treated in the department of urent vascular surgery 36 had "chronic disruptions". Validity of this term is discussed. The authors consider the term "repeated disruption" as the most adequate.

The work is devoted to studying the dynamics of endogenous toxemia by the level of middle mass peptides of blood serum in patients with acute pancreatitis. The level of middle mass peptides was investigated in 116 patients spectrophotometrically after Gabriélian with the wave length 254 nm (1st fraction, MMP-1) and with the wave length 282 nm (2nd fraction, MMP-2). It was found that the ratio of these fractions could be used as a prognostic index of the complicated course of acute pancreatitis. When the initial ration MMp-2/MMP-1 is less that 1 the risk of the development of complications of the second phase of acute pancreatitis is real. The decrease of the level of MMP-1 and MMP-2 during treatment by the 3rd-4th days is considered to be an indicator of the favorable outcome of the disease. The elevation of the level of MMP-1 and MMP-2 by the 3rd-4th days despite the treatment predicts an unfavorable outcome of the disease.

A method of determination of the duration of curative fasting in acute pancreatitis, depending on the degree of severity of patients' condition is described. The dependence between the probability of exacerbation of the process after resumption of feeding, the degree of severity of the condition at admittance, the duration of the fast vs degree of the severity of the condition in which the feeding was resumed was studied, for this purpose the method for calculation of so called coefficient of the degree of severity of acute pancreatitis was developed. 130 patients with acute pancreatitis underwent the treatment according to this method.

Retrospective analysis of surgical treatment for injuries of 408 major arteries and veins in 352 patients in the department of vascular surgery of N.V. Sklifossovsky Research Institute of Emergency Care from 1989 to 1996 is presented. Of 126 cases of prosthetic reconstructions in 72.2% autoveins were used, in 18.3%--synthetic prosthesis, and in 9.5% homologous arterial biologic prosthesis. Good results were obtained in 13.1% of patients, amputations were made in 4.8%. Lethality was 4.0%. Principles of treatment of combined injuries, prophylaxis of syndrome of inclusion and other complications are autlined.

662 case records of patients with acute pancreatitis are analysed and principles for the choice of optimal treatment of patients with acute pancreatitis (AP) are established. The most justified policy in treatment of AD patients seems to be conservative-expectant. The treatment should satisfy the phases of the course of acute pancreatitis and severity of the disease. At the first stage of the disease the treatment should be aimed at correction of pancreatic toxemia and prophylaxis of pyogenic complications. Surgical interventions at this phase are risky and hardly justified. If there are indications for drainage, laparoscopy and small invasive interventions under US control are preferable. At the second stage conservative-expectant policy should be also used as a method of choice, and treatment should be aimed at prophylaxis of purulent complications. The presence of aseptic necroses are not an absolute indication for surgery if there are no clear signs of suppuration. The presence of purulent complications is an indication for surgical treatment; extraperitoneal approaches to pyogenous areas and their drainage by wide two-lumen tubes for the following use of aspiration--lavage treatment are more preferable.

The effective curative-diagnostic laparoscopy in acute pancreatitis depends on the time of its performance and on the seriousness of the disease. The use of special mathematical formulas and nomograms makes it possible to improve results of the treatment.

The authors have developed a method of dynamic control over the patients with acute pancreatitis using the lineal coefficient of gravity rating, which is based on objective parameters. This dynamic control was applied in 300 patients and made it possible to choose the most effective methods of treatment.

The article discusses the results of medicamentous denervation of the stomach performed in 69 patients with various forms of pancreatitis 1-4 days after the onset of the disease. The efficacy of treatment was significantly higher statistically in the group of patients who were subjected to endoscopic medicamentous denervation of the stomach practically in all degrees of severity. By reducing the effect of the vagus nerve on the pathological process, this method makes it possible to improve considerably the results of treatment of patients with acute pancreatitis and shorten the terms of therapeutic fasting and in--patient treatment. Endoscopic medicamentous denervation of the stomach is indicated for all patients with acute pancreatitis in the immediate period after the onset of the disease, and the results are best when it is undertaken before destructive processes develop in the pancreas.

A method is suggested for individual calculation of optimal doses of ribonuclease and fluorofur on the basis of a standardized index--the degree of severity. A CM 1404 computer was used in solving the problem. From analysis of 500 case records by means of programs of discriminant and multidimensional linear regressive analysis a mathematical dependence was found between some parameters indirectly reflecting the severity of the patient's condition, the ribonuclease dose, and the efficacy of the treatment. A similar dependence for fluorofur was also studied. The discovered statistical regularity was realized as a nomogram for calculating the degree of severity and individual optimal doses of ribonuclease and fluorofur. The method was used in 114 patients. All the compared indices were found to be better than those in the group of patients for whom the dose of the agents (ribonuclease) was calculated on the basis of a constant dose per kg weight.

The authors propose a mathematical method of predictingthe passage of common bile duct calculi. An original mathematical formula derived by a computer allows a 98% accuracy of the prognosis. The estimations were based on the principal parameters influencingthe choledochal calculi movement defined with the help of the regression analysis. Such prediction simplifies the choice of therapeutic policy in mechanical jaundice due to choledocholithiasis.

The authors picked out 200 case records of the patients with acute pancreatitis using a method of random sample. By means of the method of step-by-step discriminant analysis, the severity of the course of the disease was prognosticated. The age of a patient, duration of the disease, body temperature, leukocytic count and glucose level in the blood, amylase activity in the urine, presence of another pathology were analysed. The solving rule permitting to prognosticate an outcome of the disease with a high degree of probability was obtained. A variable directly dependent on the severity of a course of the disease--"degree of the severity of acute pancreatitis" was established.

Eight patients with type I diabetes mellitus have been operated on to form a distal splenorenal anastomosis (DSRA). A critical period (the 6th and the 7th days) postoperation has been observed when severe metabolic acidosis develops; to prevent its development, transfusions of 4% sodium bicarbonate solution (1.5-2.01) have been administered before the critical period for 24 hrs, with the metabolic condition monitored by biochemical analyses. Studies of metabolism in these patients after surgery have revealed a complete normalization of the acid-base balance and of potassium level, as well as a reduction of the blood glucose concentration. The doses of exogenic insulin have been reduced by 30%, this being associated with a tendency to an increase of the levels of endogenic insulin, C-peptide and glucagon of the blood. This helps a better stabilization of the diabetic process after the formation of a DSRA.

Results of the preventive surgical treatment in infection of vascular prostheses were much better than those obtained after operations performed against the background of arrosive hemorrhage. The division of the operation into two steps--the extrafocal shunt at the first step and removal of the purulent prosthesis at the second step--results not only in better immediate results of the treatment of these complications, but also in reduced lethality in this group of patients. The traction mode of removal of the prosthesis is recommended to patients with a pronounced scarry process around the prosthesis.