Oxidation of h-BN on strongly and weakly interacting metal surfaces.

We used x-ray photoemission and absorption spectroscopies to study the influence of thermal molecular oxygen exposure on the h-BN/Co(0001) and h-BN/Au/Co(0001) systems. The spectral analysis was supported by density functional theory calculations. It is shown that oxygen can intercalate h-BN on Co(0001) and also be embedded into its lattice, replacing the nitrogen atoms.

Cobalt-assisted recrystallization and alignment of pure and doped graphene.

Recrystallization of bulk materials is a well-known phenomenon, which is widely used in commercial manufacturing. However, for low-dimensional materials like graphene, this process still remains an unresolved puzzle. Thus, the understanding of the underlying mechanisms and the required conditions for recrystallization in low dimensions is essential for the elaboration of routes towards the inexpensive and reliable production of high-quality nanomaterials.

Raman Spectroscopy of Lattice-Matched Graphene on Strongly Interacting Metal Surfaces.

Regardless of the widely accepted opinion that there is no Raman signal from single-layer graphene when it is strongly bonded to a metal surface, we present Raman spectra of a graphene monolayer on Ni(111) and Co(0001) substrates. The high binding energy of carbon to these surfaces allows formation of lattice-matched (1 × 1) structures where graphene is significantly stretched. This is reflected in a record-breaking shift of the Raman G band by more than 100 cm relative to the case of freestanding graphene.

[COMPARATIVE EFFECTIVENESS AND SAFETY OF NEW ORAL ANTICOAGULANTS AND WARFARIN IN PATIENTS WITH AGE-SPECIFIC NON-VALVULAR ATRIAL FIBRILLATION].

This study was designed to compare effectiveness and safety of warfarin, direct thrombin inhibitor dabigatran, Xa factor inhibitors rivaroxaban and apixaban used to prevent stroke in 280 elderly patients in patients with age-specific non-valvular atrial fibrillation. The treatment of patients aged 65-74 and 75-80 yearsfor 2 years with dab itragan (110 mg b.i.

[Comparison of Novel Oral Anticoagulants and Warfarin in Elderly Patients With Nonvalvular Atrial Fibrillation].

We compared efficacy and safety of warfarin with those of direct thrombin inhibitor dabigatran, factor Xa inhibitors rivaroxaban and apixaban used for stroke prevention in 280 patients aged 65-80 years with non-valvular atrial fibrillation. Treatment for two years with dabigatran (110 mg twice daily), apixaban (5 mg twice daily) or rivaroxaban (20 mg/day) prevented strokes no less successfully than warfarin, but more rarely caused severe intracranial hemorrhages. When selecting antithrombotic therapy in geriatric patients with non-valvular AF new oral anticoagulants may be regarded as an acceptable alternative to warfarin.

[Safety and efficacy of various modalities of antiplatelet prophylaxis of ischemic stroke in elderly patients with non-valvular atrial fibrillation].

We compared the efficacy and safety of warfarin, dabigartan, and clopidogrel used to prevent tromboembolism in 210 elderly patients with non-valvular atrial fibrillation depending on the age. In patients aged 65--74 yr treatment with dabigartan (110 mg twice daily) for 6 months was associated with ischemic stroke as frequently as warfarin therapy but less frequently than with severe hemorrhages (4.4 vs.

[Antihypertensive therapy and dynamics of vascular wall rigidity in elderly patients with non-valvular atrial fibrillation].

This comparative ultrasound study included 210 patients aged 65-80 years with non-valvular atrial fibrillation treated with the use of 4 different therapeutic modalities. Intake of perindopril, valsartan, valsartan + rozuvastatin, and lercanidipine resulted in a rise in distension index of common carotid artery, decrease of rigidity coefficient of the aortic wall and increase of the pulsed wave propagation speed. Combination of valsartan (80-160 mg/d) and rozuvastatin (10 mg/d) had the most pronounced effect on the vascular wall compliance compared with other modalities and reduced the frequency of ischemic stroke, myocardial infarction, and mortality.

[Effect of various types of antihypertensive therapy on elasticity of arterial wall in elderly patients with hypertensive disease and nonvalvular atrial fibrillation].

Basing on the data of ultrasound study we compared effects of various antihypertensive therapies on elastic properties of common carotid arteries and the thoracic aorta in 133 patients aged 65-80 years with nonvalvular atrial fibrillation (AF). The use of perindopril, lercanidipin, valsartan and its combination with rosuvastatin was associated with elevation of the distensibility index of common carotid artery and lowering of coefficient of stiffness of aortic wall compared with the initial state. Combination of valsartan (80-160 mg/day) with rosuvastatin 10 (mg/day) produced most pronounced effect on compliance of vascular wall compared with other variants of treatment.

[Comparison of three methods of antithrombotic therapy in elderly patients with nonvalvular atrial fibrillation].

We compared efficacy and safety of warfarin, direct thrombin inhibitor dabigatran and clopidogrel in prevention of stroke in 210 patients with nonvalvular atrial fibrillation (AF) aged 65-80 years. The use of dabigatran (110 mg twice daily) for 12 months or warfarin was associated with similar rate of ischemic stroke but caused less bleeding (2.8 vs.

NMR studies of carbosilane dendrimer with terminal mesogenic groups.

The 4-generation carbosilane dendrimer with terminal cyanobiphenyl mesogenic groups in dilute solution of CDCl(3) was investigated using (1)H NMR technique. The spectrum was obtained and the relaxation time, T(1), was measured in the temperature range 320-225 K. For the first time, the extrema of T(1) values were achieved for majority of the dendrimer functional groups.

Risk factors for the development of delayed graft function in deceased donor renal transplants.

Introduction: Delayed renal graft function (DGF) is associated with various factors and with a higher complication rate in the posttransplant period. Determination of center-specific risk factors may help to reduce the incidence of DGF and improve transplantation results. The aim of this study was to define risk factors for the development of DGF after renal transplantation.

[Immunity in chronic bronchitis patients with significant residual changes after prior pulmonary tuberculosis].

To study the immunological features in chronic bronchitis (CB) patients with great residual changes (GRC) after prior pulmonary tuberculosis, the authors examined two groups: 1) 40 CB patients with GRC after prior pulmonary tuberculosis (a study group) and 2) 30 CB patients without a history of pulmonary tuberculosis. The examination revealed that CB patients with GRC after prior pulmonary tuberculosis were found to have higher T lymphocytes, lower B lymphocytes on an exacerbation of the disease. The phagocytic properties of neutrophils were altered as their high phagocytic activity, decreased oxygen-dependent microbicidal activity of phagocytes with their stimulation.

[Prospective assessment of a training effect in correction of endothelial dysfunction and atherosclerosis risk factors in students (results of examination of Tomsk male students)].

Aim: To assess a training effect correcting endothelial dysfunction (ED), neurovegetative status and atherosclerosis risk factors (ARF) in male students.

Material And Methods: Ninety healthy students aged 18-25 years with ARF and ED were followed up after bicycle exercise (BE) 3 times a week: 30 males did BE for 1 month, 30--for 2 months and 30--for 3 months. Blood lipids, exercise tolerance (ET), parameters of cardiointervalography, dopplerangiography of the brachial artery and rheovasography of the forearm at rest and in tests with reactive hyperemia, hyperventilation were estimated immediately after, 1 and 3 months after BE.

Donation and transplantation in Latvia--2006.

The 75 kidney transplant operations (32.6 per million population per year) and 2 heart transplant operations were performed in 2006 in Latvia. This represents a slight decrease of 3% compared to 2005.

[Prevention of ischemic stroke in middle aged patients with atrial fibrillation. Effect of sinus rhythm maintenance, aspirin, warfarin, and simvastatin].

Patients (n=263, age 49-64 years) with persistent nonvalvular atrial fibrillation were subjected to controlled treatment aimed at restoration and maintenance of sinus rhythm (n=134) or slowing of rate of ventricular contractions. Efficacy of complementary use of combination of simvastatin with aspirin, warfarin and aspirin for prevention of ischemic stroke was assessed in both of these strategies. First strategy, supplemented with combination of simvastatin and aspirin prevented ischemic stroke and lethal outcome most successfully, while the use of warfarin was unexpectedly associated with comparative elevation of risk of ischemic stroke.

[Preclinical assessment of disturbances of vascular and vegetative reactivity of peripheral blood circulation in young men (students) with risk factors of atherosclerosis].

Hemodynamics of forearm and neurovegetative status were studied in 142 clinically healthy male students with risk factors of atherosclerosis and in 54 male students without risk factors of atherosclerosis at rest and during test with reactive hyperemia. Rheovasography of forearm, cardiointervalography, Doppler examination of brachial artery, and test with reactive hyperemia were undertaken in all subjects. The results testify to the fact that endothelial dysfunction leads to spastic state of regional hemodynamics and hyperactivity of sympathetic nervous system at rest as well as during reactive hyperemia which has a "delayed" character.

[The influence of hyperventilation in combination with active orthostasis on the condition of vegetative homeostasis in young men with atherosclerosis risk factors and endothelial dysfunction].

The aim of the study was to evaluate the effects of hyperventilation test (HVT), active orthostatic position test (AOPT), and their combination on the vegetative homeostasis in male students with risk factors of atherosclerosis (RFA) and endothelial dysfunction (ED). The mentioned tests and their combination were performed in 142 male students with RFA and ED, and 54 male students without them during brachial arterial rheovasography and cardiointervalography. Hyperactivation of the central regulatory circuit and a spastic hemodynamic condition at rest were found in subjects with FRA and ED.

[Search for an optimal therapy of patients with atrial fibrillation (results of many years of comparison of three treatment strategies).].

Patients with nonrheumatic atrial fibrillation (n=465, mean age 59.4+/-3.8 years) received controlled therapy for 7.

[Comparative morphological characteristics of bronchial mucosa in patients with chronic obstructive bronchitis and bronchial asthma].

The material for histoultrastructural study was biopsies obtained by fibrobronchoscopy from 12 patients with endogenic bronchial asthma (BA) and 4 patients with chronic obstructive bronchitis (COB). The principal periods of affection in these diseases, the role of bronchial epithelium, effector cells of inflammation, nervous elements, smooth muscle cells, microcirculatory disturbances in patho- and morphogenesis of chronic obstructive pulmonary lesions are determined. The results indicate that BA develops due to disturbances of adaptive mechanisms being in some cases the issue of COB progression.

Attitudes towards organ donation and transplantation--a study involving Baltic physicians.

The aim of this study was to identify and describe attitudes towards organ donation and transplantation among a group of Baltic physicians who are involved in this aspect of medical care. A total of 151 neurosurgeons, anesthesiologists, and neurologists anonymously answered a questionnaire between February and March 1995. The majority of physicians said they would be willing to donate their own organs after their death but disagreed with the idea of using organs from a dead person who had had a negative opinion towards organ donation.

[Systems analysis of polyparametrical syndromes in students under study-induced stress].

In addition to routine physical examinations, the polyparametrical method was used to examine 250 students to assess their health. For this, the methods of pattern discrimination and classification were employed to analyze multiparameter data. Clinical and polymetric findings correlated well.

Organ and tissue transplantation in Latvia.

From 1973 to May, 1996 585 kidney transplantations were performed in the Department of Transplantation. From 1983 to 1988 investigations on transplantation of pancreas islet cell culture were carried out. Because of financial difficulties these investigations had to be stopped.