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Liquid crystals are of great interest in the field of nonlinear optics due to their efficient response to low intensity light fields. Here we present a new, to the best of our knowledge, mechanism of a nonlinear optical response which is observed for a dye-doped dual-frequency nematic liquid crystal. The local increase in temperature caused by the absorption of light beam in the liquid crystal medium leads to spatial variation and inversion of the sign of the dielectric anisotropy. When an alternating current electric field with a frequency close to the cross-over frequency is applied to the liquid crystal cell, the planar orientation sustains at the beam periphery, but elastic deformation occurs in the irradiation region. In the case of a dye dopant with negative absorption dichroism, a first-order orientational transition with large bistability region is obtained.

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PURPOSE: To study the effect of ranibizumab and aflibercept on the thickness of retinal nerve fiber layer (RNFL) in patients with neovascular age-related macular degeneration (nAMD) and primary open-angle glaucoma (POAG). MATERIAL AND METHODS: The study included 62 patients (62 eyes) with nAMD and comorbid POAG. Patients were divided into two groups depending on the anti-VEGF treatment. The first group included 42 patients (42 eyes) who received injections of ranibizumab. The second group consisted of 20 patients (20 eyes) who received aflibercept. All patients received three injections of ranibizumab or aflibercept with one-month intervals. In addition to standard ophthalmic examination, patients underwent optical coherence tomography of the macular area and peripapillary RNFL. RESULTS: After anti-VEGF treatment, patients of both groups exhibited improvements expressed in reduced macular edema, increased visual acuity and absence of intraocular pressure (IOP) changes, as well as no statistically significant changes in the width and depth of excavation. There was a statistically significant decrease of peripapillary RNFL thickness in the temporal quadrant after treatment. CONCLUSION: The decrease of peripapillary RNFL thickness in the temporal quadrant occurs due to resorption of macular edema. In the absence of statistically significant changes in IOP, width and depth of excavation, intravitreal injections of ranibizumab and aflibercept can be considered safe treatment options for patients with concomitant nAMD and POAG.

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PURPOSE: To assess the effect of intravitreal administration of anti-VEGF drugs ranibizumab and aflibercept on the functional state of the visual pathway in patients with neovascular age-related macular degeneration (nAMD) and primary open-angle glaucoma (POAG) using the method of recording visual evoked potentials (VEP). MATERIAL AND METHODS: A total of 54 patients (54 eyes) with nAMD and POAG were examined. The control group consisted of 39 healthy patients (39 eyes). The study included 24 patients (24 eyes) with stage IA POAG, 23 patients (23 eyes) with stage IIA POAG, 7 patients (7 eyes) with stage IIIA POAG. All patients with nAMD and POAG were given intravitreal injection of anti-VEGF drug: 35 patients received ranibizumab, 19 patients received aflibercept. Injections were performed monthly for 3 months. Ophthalmologic examination included visometry, biomicroscopy, retinal OCT using SPECTRALIS tomograph ('Heidelberg Engineering GmbH', Germany). VEP were recorded on EP-1000 Multifocal ('Tomey', Germany). All ophthalmologic studies were performed prior to administration of the anti-VEGF preparation and after the 3rd injection. RESULTS: After the third intravitreal injection of anti-VEGF drugs, best corrected visual acuity (BCVA) increased to 0.46±0.1 (p=0.001). According to OCT, central retinal thickness decreased by an average of 110.6 µm, the total volume of the retina decreased by 1.3 mm3, total thickness RNFL - by 3.8 µm (p<0.05). A decrease in the peak latency and an increase in the amplitude of the component P100 of VEP were noted. Statistically significant differences in indicators of VEP between antiangiogenic drugs ranibizumab and aflibercept were not detected (p>0.05). CONCLUSION: Intravitreal administration of anti-VEGF drugs ranibizumab and aflibercept has no negative influence on the functional state of the visual pathway in patients with nAMD and POAG. Intravitreal injections of ranibizumab and aflibercept can be considered a safe treatment option for patients with nAMD and POAG.

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Vascular endothelial growth factor (VEGF) is known as a key mediator of angiogenesis, but there is also evidence of its broad significance in neurogenesis and neuroprotection. Cytokines of the VEGF family affect neovascularization and neural development in the brain, particularly during cerebral ischemia, in which there is a coordinated interaction of angiogenesis and neurogenesis that contributes to rapid functional recovery. This review examines the involvement of VEGF family members and their receptors in physiological and pathophysiological processes as well as the relationship between VEGF-A plasma levels and ischemic stroke.

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Light-induced director orientation of polymeric liquid-crystalline systems was investigated. The materials under study were composed of a nematic liquid-crystalline polymer (NLCP) and a small amount (0.05-0.5 wt.%) of conformationally active (azobenzene) or stable (anthraquinone) dye impurity. Light action on the homogeneously aligned polymer films above glass transition temperature leads to the director reorientation and, consequently, to a change in the extraordinary refractive index. The effect is associated with the dye molecule excitation and related change of intermolecular forces. In the case of NLCP with conformationally active dye dopant, an extremely high orientational optical response was detected (nonlinear coefficient is n_{2}∼0.1cm^{2}/W). In contrast, the efficiency of orientational light action on NLCP with conformationally stable dye dopant is of the same order of magnitude as that of dye-doped low-molar-mass liquid crystals. At the normal light incidence on the NLCP doped with azo-dye, the threshold director orientation is observed which is similar to the Fréedericksz transition under the action of magnetic and electric fields. The obtained high-orientational optical response of NLCP caused by azo-dye dopant in combination with the possibility of the recording of deformed structure in the glassy state, typical for polymer compounds, reveals new opportunities in photonics applications.

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Using the autoradiographic method, we studied the kinetics of DNA synthesis over the mitotic cycle in mouse corneal epithelium cells in delayed periods after γ-irradiation in different points of the S phase of the first mitotic cycle. The index labeled cells during 1-3 periods of DNA synthesis most adequately reflects quantitative changes in the cell population composition after cell exposure during the first S period. The relative number of labeled S phase cells in the second mitotic cycle in experiments where the cells were irradiated in the S1 phase of the first S period was 4-fold lower than in experiments where the cells were exposed during S2 phase. This effect is determined by inhibition of the transcription factors activation. It seems that two territorially different sites of the genome controlling the regulatory stimuli and involved in modification of the quantitative composition of the population are responsible for changes in its quantitative balance.

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The clinical observation of the successful treatment of newly diagnosed fibro-cavernous pulmonary tuberculosis caused by mycobacteria of multidrug-resistant tuberculosis and the results of control of the effectiveness of treatment with modern high-tech radiation methods are presented. The necessity of an individual approach to the treatment of tuberculosis in this category of patients is shown.

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In four groups of rabbits on model of a heavy alkaline burn of a cornea and a limbus of various extent character and outcomes of healing of an eye surface as a result of early (it is direct after a burn) applications is investigated: only conservative treatment - group I, conservative treatment + time blepharorrhaphy - group II, conservative treatment + covering of a cornea and a limbus of amnionic membrane - group III, and also combinations of conservative treatment, temporary of blepharorrhaphy and coverings of a cornea and a limbus amnionic membrane - group IV. In all groups conservative treatment included: an instillation of maxitrol within 14 days with transition to a mortgaging of Unguentum Tetracyclini of 1% 3 times a day. Depending on width of sector of the burn measured in circular degrees, each group included 4 subgroups: 60° - a subgroup "A", 120° " " - 180° - "B", 270° "Γ" - (on 4 eyes in a subgroup). Results estimated daily within the first 10 days, and further every 5 days (during 3 months) after a burn with photoregistration at colouring of an eye surface of 1% a solution fluorescein-natrium. On the basis of the received results it is established that the early fortnight time blepharorrhaphy (as addition to conservative treatment) is the most effective and accessible method (from considered) optimisation of healing of an eye surface at heavy burns of eyes with capture to 75% of the area of a cornea and a limbus.

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Interaction of light and ac electric fields with a nematic liquid crystal (NLC) doped with nanosized second-generation carbosilane codendrimers containing terminal azobenzene fragments has been studied. A first-order Freedericksz transition in the linearly polarized light, accompanied by an intrinsic bistability in a wide region, was observed. An additional ac electric field decreases the light-induced Freedericksz transition threshold and narrows the bistability region. Light illumination transforms the second-order electric-field-induced Freedericksz transition to a first-order one. The width of the bistability region increases with the light wave intensity. The theory of the interaction of light and ac electric fields with the dendrimer-doped NLCs is developed taking into account an additional (with respect to the undoped nematic host) dependence of the optical torque on the angle between the director and the light field.

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Optimal conditions for the formation of stable protoplasts of S. recifensis subsp. lyticus 2435 were defined and the use of the protoplasting procedure to increase the activity of the synthesis of extracellular enzymes was shown in principle possible. The level of the synthesis of glycosidases and lytic endopeptidases by the isolated variant II-29 was higher than that the initial strain by 40-45 per cent which was due to the enrichment of the population with more active variants.

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Experimental studies in laboratory animals showed reserpine in doses of 0.01-0.05 mg/kg body weight to inhibit the development of rabies infection in white mice and rabbits by 40.0-83.4% depending on the dose and mode of administration. The inhibiting properties of reserpine were demonstrated for both fixed and street rabies virus strains. The protective effect of the drug was manifested after parenteral and oral administration to the infected animals. The experimental data suggest that reserpine may be used as an antiviral drug for protective treatment of rabies in the incubation period.

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Measurement of pressures in the pharyngeal esophageal segment (P-E segment) is complicated by the vertical motion and by the rapidly changing pressures in the segment. The sensors move superiorly and inferiorly with respect to the P-E segment during the swallow. This study examines the validity of manofluorographic measurements taken in the P-E segment by using a catheter with sensors spaced at 1 cm intervals. Seven normal volunteers were tested. Measurements were similar using one sensor and using an average of five sensors. During the time of bolus passage, the P-E segment is open and the bolus itself equalizes pressures measured within the bolus.

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Treatment results were compared in 2 groups of patients with advanced small-cell lung cancer. Group 1 (52 cases) received chemoradiation treatment alone whereas in group 2 (41 patients) it was combined with general hyperthermia (temperature 40-41.8 degrees C during 3-4 hours). Response was observed in 63.5% of patients of group 1 and 79.5% of those in group 2. Complete response rates did not differ significantly (23.1 and 28.2%, respectively). 40.6 +/- 8.2% of patients receiving chemoradiation treatment plus general hyperthermia survived over 1 year, 20.5 +/- 7.1%--over 1.5 years and 15.9 +/- 6.7%--over 2 years. In the control group, the respective rates were 22.2 +/- 5.8%, 5.1 +/- 3.4% and 5.1 +/- 3.4%.

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From 1963 to 1985, 232 operations were carried out for constriction of the pulmonary artery in ventricular septal defect (VSD) with high pulmonary hypertension with 6% mortality. 74 patients were examined after a palliative operation. According to the results of catheterization of the heart cavities, the effect of the first stage of surgical correction of the defect was good in 55, satisfactory in 8, and poor in 11 patients. Radical operation for closure of VSD and debanding of the pulmonary artery were performed in 52 patients with 19.2% hospital mortality. During follow-up of the late-term results of two-stage correction of the defect catheterization of the heart cavities with angiocardiography was conducted in 13 patients, pressure in the pulmonary artery in 12 of them was normal (26.4 +/- 1.8%). Prevention of hemorrhage during freeing of the heart from adhesions as well as sparing techniques of VSD closure may reduce mortality in repeated surgical intervention essentially.

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