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This paper studies the effect of the laser melting process (LMP) on the microstructure and hardness of a new modified AlCuMgMn alloy with zirconium (Zr) and Yttrium (Y) elements. Homogenized (480 °C/8 h) alloys were laser-surface-treated at room temperature and a heating platform with in situ heating conditions was used in order to control the formed microstructure by decreasing the solidification rate in the laser-melted zone (LMZ). Modifying the AlCuMgMn alloy with 0.4 wt% Zr and 0.6 wt% Y led to a decrease in grain size by 25% with a uniform grain size distribution in the as-cast state due to the formation of Al 3 (Y, Zr). The homogenization dissolved the nonequilibrium intermetallic phases into the (Al) matrix and spheroidized and fragmentized the equilibrium phase's particles, which led to the solidification of the crack-free LM zone with a nonuniform grain structure. The microstructure in the LMZ was improved by using the in situ heating approach, which decreased the temperature gradient between the BM and the melt pool. Two different microstructures were observed: ultrafine grains at the boundaries of the melted pool due to the extremely high concentration of optimally sized Al 3 (Y, Zr) and fine equiaxed grains at the center of the LMZ. The combination of the presence of ZrY and applying a heating platform during the LMP increased the hardness of the LMZ by 1.14 times more than the hardness of the LMZ of the cast AlCuMgMn alloy.

The mechanical properties and microstructure of as-cast and homogenized AA7075 were investigated. This alloy was modified by adding transition elements 0.3%Sc + 0.5%Zr, 1%Ti + 0.2%B, and 1%Fe + 1%Ni for use in additive manufacturing applications. After adding Ti + B and Sc + Zr, the structure became uniform and finer with the formation of the Al 3 (Sc, Zr) and TiB 2 phases. Coarse structures were obtained with the formation of an extremely unfavorable morphology, close to a needle-like structure when Fe + Ni was added. The mechanical properties of the modified alloys were increased compared to those of the standard alloy, where the best ultimate tensile strength (UTS) and yield strength (YS) were obtained in the AA7075-TiB alloy compared to the standard alloy in as-cast and homogenized conditions, and the highest hardness value was provided by Fe + Ni additives. The effect of the laser melting process on the microstructure and mechanical properties was investigated. Single laser melts were performed on these alloys using 330 V and a scanning speed of 8 mm/s. During the laser melting, the liquation of the alloying elements occurred due to non-equilibrium solidification. A change in the microstructures was observed within the melt zone and heat-affected zone (HAZ). The hardness of the laser-melted zone (LMZ) after adding the modification elements was increased in comparison with that of the standard alloy. Corrosion testing was performed using a solution of 100 mL distilled water, 3.1 g NaCl, and 1 mL HCl over 5, 10, and 30 min and 1 and 2 h. The corrosion resistance of the alloy modified with FeNi was low because of the non-uniform elemental distribution along the LMZ, but in the case of modification with ScZr and TiB, the corrosion resistance was better compared to that of the standard alloy.

Magnetic resonance imaging (MRI) is the leading method of radiation diagnosis of brain tumors. In conditions of the artificial contrast enhancement there are more clearly differentiated the boundaries of the tumor node on the back of peritumorous edema and identified structural features of the tumor. The purpose of this study was to examine indicators of the dynamics of accumulation and removal of contrast agents by brain tumors in MRI technique with dynamic contrast and identify opportunities of this method in the differential diagnosis of various types of tumors.

Molecular chaperons can effectively activate innate and adaptive anti-tumor immune response. In the model of intracranial glioma C6 in Wistar rats we assessed immunomodulatory activity of recombinant protein Hsp70 in case of local, intratumoral injection. Single intratumoral infusion of chaperone had led to dramatic delay in tumor volume growth (on MRI of rat brain), which was accompanied by increase in survival rates. Incubation of rat spleenocytes with C6 cells elevated the levels of INF-gamma, that shows an immunologically specific T-cell response. With immunohistochemical assay we observed a marked infiltration of the tumor by T-lymphocytes and NK-cells. Thus, purified Hsp70 can efficiently induce innate and adaptive anti-tumor response and could be used as adjuvant in treatment of malignant brain tumors of central nervous system.

In the article was analyzed the usage of the technical devices of medical assignment of NATO armed forces during the last military conflicts in different countries and prospects of its perfection. Among the most important programs were outlined: work on the systems of telemedicine with possibility of its usage in battle conditions, development of the independent life-support system in case of battle trauma and progressive medical mobile centers on the base of new motor carrier.

The article presents an observe of vehicles of medical evacuation (VME), existing in medical service of the Armed Forces of RF, intended for transporting of ill and wounded persons with delivery of emergency care in passing. Were presented perspective examples of CMV "Aybolit" and VME of middle and grand evacocapacity, pertained to elaboration. There was made a conclusion that the new generation of VME on chassis of the army all-wheel-drive vehicles, having an armor defense (complex of local defense), system of smooth transporting and loading-unloading system, permits solve questions of evacuation of ill and wounded persons from battle field more effectively.

An aim of the study was to investigate a relationship between global and local brain atrophy with neurological impairment (motor dysfunction) in multiple sclerosis (MS) patients with different levels of disease severity. Fifty five patients with definite MS (Mc Donald's criteria), aged 18-60 years, disease duration 1-30 years, and 25 healthy age-matched controls have been studied. Neurological assessment (Kurtzke and EDSS scales) was performed in the all patients. The patients were divided into 3 groups: EDSS<3.5 mild disability, EDSS 3.5-6.0 moderate disability, EDSS>6.0 severe disability. In MS patients, the global brain atrophy was accompanied by the local atrophy of subcortical structures (thalamus, basal ganglia) and cerebellum. The processes of cerebral grey matter total and local atrophy were not similar. The progression of MS, neurological impairment is accompanied by the cerebellum and lentiform nuclei atrophy. There was the decrease of brain parenchyma volume, nucleus caudate and cerebellar local atrophy in patients with moderate disability. The severe disability was correlated with the thalamic atrophy and marked basal ganglia and cerebellar atrophy. Thus, we can suppose that the thalamic atrophy is important for the development of severe motor dysfunctions in MS patients.

The regional brain glucose metabolism after the intravenous drop-by-drop infusion of saline and 50 mg of cavinton was measured with positron-emission tomography (PET) in the right middle brain artery in 5 patients with ischemic stroke. The increase of glucose metabolism was found in the region of post stroke cystic-focal and perifocal changes as well as in contralateral regions. The dose of cavinton (50 mg) was safe and well-tolerated by patients. The use of PET in evaluating of glucose metabolism changes in the brain helps in prognosis of the disease.

Potential of contrast-enhanced MR imaging (MRI) in diagnosis of breast tumors was studied in 112 patients aged 18-64 (76 suspects and 36--after combined treatment). The method proved highly-effective and specific--92 and 81%, respectively. The best timing was 3 months after surgery and 8 months after irradiation. No significant advantage of either one- or polymolar contrast agents was observed. MRI is highly efficient in diagnosing hypervascular formations, tumor grading and making prognosis. It is a method of choice in evaluating neoadjuvant polychemotherapy findings and combined treatment monitoring.

The paper discusses the data from dynamic follow-up of immunohistologically confirmed glioblastomas of the brain using proton magnetic resonance imaging (+H MRI) (25). Study was undertaken before and after therapy and resumed for 6-8 months after. Cholin concentration peaks and N-acetyl-aspartate decrease in gliomas appeared to be higher than those in anaplastic astrocytomas. Moreover, N-acetyl-aspartate peaks were obliterated by large necrotic areas in glioblastoma. Instead, lipid and lactate concentrations peaked thus suggesting pathological changes. A necrotic area developed in the course of radiochemotherapy involving peaks for wide profile of lipid and lactate concentrations coupled with lowered levels of other metabolites.

Stereotactic radiosurgery was performed in 42 patients (1997-2007). They presented with 47 cavernous angiomas and 44 of them underwent surgery. Single focal dosage varied 3-9 Gy while total one--18-54Gy. After treatment and 2-year followup, neurologic symptoms regressed in 21 (68%), tumors were smaller (MRI) in 10 (32.3%) and severe convulsions abated in 5 patients out of 9. No cerebral hemorrhage was reported within 9 years although 63.7% of tumors were located in deep cerebral structures and hemorrhage occurred as a precursor in 83%.

The report deals with potential of present-day techniques for radiological imaging, differential diagnosis and working out of modalities of treatment for primary and metastatic hepatic tumors. Results of complex examination (ultrasound, CT, MRI, PET using fluorine -18 FDG) of patients with benign and malignant tumors are discussed. Sensitivity and specificity of each procedure have been identified to be used in diagnosis of large-size tumors.

The results of the dynamic study of patients with epileptic seizures in chronic and acute cerebral vascular pathology are presented. Various methods of structural and functional neurovisualization--magnetic resonance tomography using perfusion- and diffusion-weighted imaging, proton magnetic resonance spectroscopy, positron emission tomography, single photon emission computed tomography were used. Based on the results obtained in the study, the authors discuss etiopathogenetic variants of the development of these seizures and new possible approaches to the complex treatment besides the administration of antiepileptic medications.

The purpose of the investigation was to study the capacities of 18F-FDG positron emission tomography (PET) in the diagnosis and evaluation of the efficiency of treatment for resistant anxiety-obsessive disorders (AOD). 18F-FDG PET was performed in 21 patients with AOD. In 17 cases, the studies were made before and after therapy. Fourteen patients underwent stereotactic surgical intervention. Pretreatment 18F-FDG PET showed that the patients with AOD had hypermetabolism in the cingulated gyri, caudate nuclei, and thalamus in 7, 8, and 6 cases, respectively. A varying clinical improvement (by the Y-OCS and Spilberger scales) was observed in all the examinees after complex or drug treatment throughout the follow-up. According to the data of PET, these patients were observed to have significantly reduced metabolism of glucose in the anterior cingulated guri and its increased metabolism in the heads of the caudate nuclei and thalamus. The metabolic changes detected by PET are strongly and moderately correlated with the pattern of a clinical picture (p < 0.05). It is concluded that the use of 18F-FDG PET makes it possible to provide more accurate insight into the pathogenetic mechanisms responsible for the development of AOD, to objectify the choice of targeted intracerebral structures in order to perform stereotactic neurosurgical interventions, and to optimize drug therapy and to evaluate the efficiency of the treatment performed in early periods.

The brain from 6 patients who died of multiple sclerosis was studied with MR tomography (MRT), macroscopy, light (CD 3, CD 20, LCA antigens) and electron microscopy (EM). Typical foci of demyelinization (plaques) were found in all cases. Alterations of brain arteries were found particularly in arteries of narrow lumen--with disturbance or even absence of elastin and muscle layer. Up to 30% of the vessels were surrounded by microcavities. Perivascular infiltrates consisting primarily of T lymphocytes were observed around the vessels (up to 70% of all vessels). This indicates the importance of vascular changes in the disease pathogenesis. Four variants of demyelinization (plaques) are distinguished depending on the degree of destruction of myelin, axons and glia. Two types of cells were found in the plaques with most pronounced changes: astrocytes and newly formed oligodendrocytes. Classification of plaques is suggested.

The aim of the study was to investigate the structural-functional changes in the cerebral gray matter (cortical and subcortical areas) of patients with multiple sclerosis (MS) depending on the disease severity. One hundred and seven patients (107) with definite diagnosis of MS (Mc Donald's criteria), aged 16-60 years, illness duration 1-30 years, and 21 healthy age-matched controls have been studied. Neurological assessment including Kurtzke and EDSS scales (range 0-8) was performed in all the patients. The patients and controls underwent MRI with a 1,5 imager and PET using 18F-flurodeoxyglucose (FDG). A type of the disease course was determined as remitting in 63 patients, primarily-progressive in 8, remitting progressive in 6 and secondary-progressive in 30. To analyze pathogenesis of the disease progression, the patients were divided into 3 clinical groups: (1) remitting (RRMS, n=63); (2) progressive (PRMS) with EDSS < or =6 (n=34); 3) PRMS with EDSS >6 (n=11). Along with the progression of MS from RRMS to PRMS and increasing of EDSS, the rCMRglu reduction of the cerebral gray matter developed from the supplementary motor cortex of a dominant hemisphere to the marked global reduction of cerebral metabolic rate in the PRMS group (EDSS >6). In the PRMS group with EDSS56, there was functional reorganization of cortical and subcortical areas compensatorily developing with the disease progression. In the PRMS group with EDSS >6, the data obtained did not support the evidence for the regional compensatory increase of rCMRglu in the same brain areas. Decompensation of the functional cortical reorganization in the PRMS group with EDSS >6 correlated with diffuse brain atrophy as well as with atrophy of the gray matter of the regional basal ganglia, first of all of the thalamus.

Present paper presents proton MRS investigation results. The investigation was carried out with Magnetom Vision device. Twenty-five patients in the age of 20-44 years suffering with generalization epileptic fits validated by EEG (no visible changes on MRT) were examined. In all cases independently on the localization of the changes, decreasing of NAA and increasing of Cho were recorded. At one side temporal lobe injury recorded by EEG at the damaged part decreasing of NAA/Cr and NAA/Cho + Cr ratios were registered. Patients with bilateral changes registered by EEG showed non-equal changes of metabolite concentration on both sides. Examination of patients suffering with distinct symptoms of temple epileptics has shown ipsilaterality decrease of NAA and Cr concentration. But on the injured side NAA/Cr ratio decrease was more distinct. In general, the laterality was recorded in 14 patients out of 22 with pathological changes registered by proton MRS and in 10 patients out of 14 the above mentioned changes corresponds to the side of the fit initiation. In the patients with bilaterality changes NAA/Cr ratio asymmetry was recorded in all cases, but the most distinctly in the medium part of the temple lobe. Comparison of data recorded in 8 patients suffering with one side fit complex has shown significant asymmetry of metabolites which was observed in ipsilaterality and contra laterality NAA ratio obtained in hippocampal areas. Difference in NAA ratio obtained between left and right sides are 19-25%. Left-right ratio of other metabolites corresponded to that ratio in the control group and was symmetrical.

Magnetic-resonance imaging (MRI) is considered to be the most informative non-invasive method in diagnosis, differential diagnosis and estimation of activity of multiple sclerosis (MS). MRI data of 270 patients with clinically and laboratory definite MS were analyzed to assess diagnostic MRI-criteria for MS, MRI presentations at the time of first clinical manifestation of the disease, neuroimaging patterns in children and elderly persons with MS. The MRI variants of MS are substantiated. Neuroimaging data of cervical spinal cord in 28 patients with MS are presented in parallel with corresponding clinical data. The most typical patterns are singled out. The data of brain 1H-magnetic-resonance spectroscopy (MRS) in 20 patients with MS and 8 patients with inflammatory and vascular disorders were analyzed to reveal biochemical distinction between MS and non-MS lesions as well as changes in normal appearing white matter in MS. The differential-diagnostic value of MRS is limited although decreased N-acetyl-aspartate peak is characteristic for MS lesions and in some cases in normal appearing white matter in primary-progressive MS.

Proton magnetic-resonance spectroscopy (PMRS) was used to measure the levels of inositol/myoinositol (Ins), choline, creatine/phosphocreatine (Cr), glutamine/glutamate (Glx/Glx1), N-acetylaspartate (NAA), gamma-aminobutyric acid (GABA) and lipids were measured in the foci of demyelinization in the brains of 59 patients with multiple sclerosis (MS). Magnetic-resonance imaging was performed during a single investigation. A control group comprised 20 healthy individuals. PMRS revealed significant alterations in the levels of metabolite in all the patients as compared with the controls: decreases in NAA by 23-52%, in Cr by 12-21%, in choline by 15-26%; increases in Ins by 51-63%; as well as the appearance of lipids (up to 100%). In MS, there were reduction in NAA/Cr, NAA/choline, and NAA/choline/Cr ratios by 12-53; 10-19; and 57-82%, respectively. As compared with the remitting MS, secondary-progressive MS showed decreases in the content of NAA by 23-25%, NAA/(choline + Cr) by 48-54% and increases in the levels of Ins and lipids by 50-76%. In remitting MS, there was a strong correlation between the NAA/Cr ratio and the volume brain lesion. It is concluded that PMRS evaluated the extent, pattern and activity of demyelinization (by the levels of Ins, NAA, Cr, lipids) and the intensity of cerebral atrophy (by NAA levels, NAA/Cr ratio). The findings testify that there are neurochemical differences between remitting and secondary-progressive MS.

The role and position of proton magnetic resonance spectroscopy have been studied in diagnosis of brain diseases. 114 patients with various diseases of the brain have been examined (multiple sclerosis--41, insults of different etiology--17, encephalopathy--12, AIDS infection--23, epilepsy--12, reduction of the intellectual ability of various etiology--9). MR tomography and 1HMR Spectroscopy have been done with Magnetom "Vision", 1.5 T (Siemens) in the CRIRR, St. Petersburg. To get a proton magnetic-resonance specter, SVS&#95;STEAM, SVS&#95;STEAM-20 and SVS&#95;SE-135 sequences have been used with the following parameters: TR 5000 ms, TE 10, 20 and 135 ms respectively, number of acquisitions--100. Typical changes of metabolities in every group have been revealed. The performed examinations have shown that proton magnetic resonance spectroscopy enables to widen our know-ledge about the nature of pathologic changes, that grow with different diseases of the brain.

Patients with chronic hepatitis were found to develop an inadequate di- and natriuretic responses to osmotic agents administered into the gastrointestinal tract. In liver cirrhosis, the intensity of adaptive responses decreases or they completely disappeared. The causes for these abnormalities are impairment of osmoregulatory reflex links and dyscoordination of humoral factors.

During formation of hepatic cirrhosis in animals, excessive potassium loss has been found to depend on the increased loading of a nephron by its cation at its early stage and on abnormally changed tubular processes at late stages.

The paper is devoted to a study of the results of clinicoroentgenological and endoscopic investigation of 188 patients aged 23 to 60 who developed jejunal peptic ulcer. It was done to specify the features of an x-ray picture of jejunal peptic ulcers with relation to the cause of ulcer development and optimum methods of x-ray investigation. The predominant localization of peptic ulcer in the jejunal efferent loop and its typical ulcero-cicatricial deformity were established. Jejunal peptic ulcers developing as a result of an insufficient area of resection, are characterized by a relatively benign course of the disease. In case ulcer development was determined by the residual antral stomach mucosa at the duodenal stump or by the Zollinger-Ellison syndrome, considerable pathological changes (gigantic ulcer sizes greater than 2.5 cm and a sharp deformity of the jejunal efferent loop) were noted.