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1.
Ter Arkh ; 93(6): 679-684, 2021 Jun 15.
Artigo em Russo | MEDLINE | ID: mdl-36286834

RESUMO

BACKGROUND: High risk of cardiovascular events is among leading problems in chronic kidney disease (CKD). Serum Klotho is supposed to be cardio- and nephroprotective; modification of its levels may be important in CKD. AIM: To evaluate the impact of vitamin D receptor activators (VDRA) on Klotho serum levels in CKD 3b4 stages patients. MATERIALS AND METHODS: Study included 90 CKD 3b4 stages patients who had elevated serum levels of parathyroid hormone (PTH). From them, 47 patients (group 1) started to treat with the selective VDRA (zemplar 1 mcg/day), and 43 patients (group 2) started to treat with non-selective VDRA (alfacalcidol 0.25 mcg/day). At baseline and after 12 months we conducted routine examination, serum Klotho measurement, and broad cardiovascular examination. RESULTS: The patients who managed to maintain a target serum PTH level, had higher Klotho serum level (p=0.037) at the end of the study. Patients who used selective VDRA significantly more often reached the target PTH level (p=0.032), had higher serum Klotho levels (p=0.037), and glomerular filtration rate (eGFR) level (p=0.048) than patients who used non-selective VDRA. In addition, patients treated with alfacalcidol more than 6 months, more often had hypercalcemia (p=0.047) and hyperphosphatemia (p=0.035). Group 2 showed higher: pulse wave velocity (p=0.051), left ventricular myocardial mass index (p=0.033), and more advanced heart valve calcification (p=0.038). CONCLUSION: Successful parathyroid hormone level control with vitamin D receptor activators was associated with higher serum Klotho, selective agents having shown greater effect. Long-term treatment with selective vitamin D receptor activators may contribute to cardiovascular calcification prevention by modifying Klotho levels.


Assuntos
Receptores de Calcitriol , Insuficiência Renal Crônica , Humanos , Glucuronidase , Estudos Prospectivos , Análise de Onda de Pulso , Proteínas Klotho , Insuficiência Renal Crônica/complicações , Hormônio Paratireóideo
2.
Ter Arkh ; 93(2): 193-198, 2021 Feb 15.
Artigo em Russo | MEDLINE | ID: mdl-36286636

RESUMO

Primary biliary cholangitis and sarcoidosis are both cholestatic liver diseases. Currently, there are no established specific criteria for distinguishing the diseases from each other; diagnosis is based on the anamnesis, as well as the results of physical, laboratory and instrumental examination. The case report presents a female patient with a rare combination of histologically verified liver sarcoidosis and primary biliary cholangitis. Despite the similar clinical manifestations, the approaches to the treatment of these diseases are completely different, that underlines the importance of the differential diagnosis to exclude combined liver damage.

3.
Ter Arkh ; 91(4): 8-16, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31094470

RESUMO

Sarcoidosis is a multisystem granulomatous disease of unknown etiology. Liver is frequently involved in the pathological process. Wide range of clinical manifestations can be seen: from asymptomatic lesion with normal liver function tests to cirrhosis with portal hypertension. Biopsy plays the key role in diagnosis of the hepatic sarcoidosis. It is essential for morphological diagnosis to exclude other causes of granulomatous liver disease, most often - primary biliary cholangitis. Nowadays there are no standard treatment protocols for patients with hepatic sarcoidosis.


Assuntos
Cirrose Hepática Biliar , Cirrose Hepática , Hepatopatias , Sarcoidose , Biópsia , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática Biliar/etiologia , Hepatopatias/etiologia , Sarcoidose/complicações
4.
Opt Express ; 25(6): 6664-6677, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28381011

RESUMO

In this work, numerical heat transfer simulations of direct water-cooled gain modules for thin disk (TD) Ti:Sapphire (Ti:Sa) power amplifiers are presented. By using the TD technique in combination with the extraction during pumping (EDP) method 100-TW class amplifiers operating around 300 W average power could be reached in the future. Single and double-sided cooling arrangements were investigated for several coolant flow velocities. Simulations which upscale the gain module for multiple kilowatts of average power were also performed for large aperture Ti:Sa disks and for multiple disks with several coolant channels.

5.
Opt Express ; 18(25): 25847-54, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21164930

RESUMO

The propagation of high intensity laser beams is excessively affected by optical nonlinear effects, thereby the knowledge of the nonlinear refractive indices of the beam guiding media is indispensable in the design of laser systems and experiments. Apart from undesired self-focusing, several areas of modern laser spectroscopy can utilize optical nonlinearity, from LiDAR measurements to filamentation. In this paper we report on a direct measurement of pressure dependent nonlinear refractive index of Ar, N2, Ne, Xe, and air between 0.05 mbar and 1 bar, based on the powerful technique called spectrally and spatially resolved interferometry. In this way the total value of nonlinear refractive index is measured, that is the sum of all elementary phenomena contributing to the intensity dependent refractivity of the gases.


Assuntos
Teste de Materiais/instrumentação , Gases Nobres/química , Refratometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Dinâmica não Linear , Pressão
6.
Appl Opt ; 47(27): 4856-63, 2008 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-18806842

RESUMO

Dispersion of femtosecond laser pulses propagating in Ar, He, Kr, N(2), Ne, Xe, and their mixtures is measured by spectrally and spatially resolved interferometry. By varying the gas pressure in a 4.5 m long tube between 0.05 mbar and ambient pressure, the first, second, and third order phase derivatives of broadband laser pulses are determined at 800 nm under standard conditions. The dispersion of gases and gas mixtures obeys the Lorentz-Lorenz formula with an accuracy of 0.7%. Based on the measured pressure dependent dispersion values in the near infrared and the refractive indices available from the literature for the ultraviolet and visible, a pressure dependent Sellmeier-type formula is fitted for each gas. These common form, two-term dispersion equations provide an accuracy between 4.1x10(-9) (Ne) and 4.3x10(-7) (Xe) for the refractive indices, from UV to near IR.


Assuntos
Algoritmos , Interferometria/métodos , Modelos Químicos , Gases Nobres/química , Refratometria/métodos , Misturas Complexas/análise , Misturas Complexas/química , Simulação por Computador , Luz , Gases Nobres/análise , Espalhamento de Radiação
7.
Rev Sci Instrum ; 79(3): 033303, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18377003

RESUMO

Laser accelerated proton beams have been used for field characterization in expanding plasmas. The Thomson parabola spectrometer, as a charged particles analyzer, also allows precise measurement of the charged particles' trajectories. The proton's deflections by fast changing plasma fields can be measured with the new design of the Thomson parabola spectrometer and, therefore, it can be applied for proton deflectometry. It is shown that from resulting spectrograms the plasma field dynamics can be reconstructed with high temporal resolution. In a proof-of-principle experiment, a weakly relativistic plasma expansion is studied as an example.

8.
Sud Med Ekspert ; 50(3): 8-12, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17598439

RESUMO

The authors give statistics on most frequent variants of location of primary injuries (LPI) in car drivers (CD) and front seat passengers (FSP) of left-hand wheel cars. There was neither significant intra- and intergroup difference in the incidence of injuries nor LPI both in the groups and between the groups. Prevalence of LPI in CD on the left and in FSP on the right side of the body was not confirmed statistically. Significantly higher frequency of pubic injuries was found in FSP versus CD which is explained by different biomechanical route of the body dislocation in strong primary blow. The authors believe this sign to be distinctive and propose to use it in forensic-medical examinations. They also advocate wider use of section roentgenography and medico-criminalistic methods to raise detectability of characteristic body injuries which is essential because of a great rise in the number of modern cars on the roads decorated with less traumatic materials.


Assuntos
Acidentes de Trânsito , Patologia Legal/estatística & dados numéricos , Ferimentos e Lesões , Acidentes de Trânsito/mortalidade , Acidentes de Trânsito/estatística & dados numéricos , Adulto , Automóveis , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Índices de Gravidade do Trauma , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/patologia
9.
Phys Rev Lett ; 96(14): 145006, 2006 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-16712088

RESUMO

We report on the generation and laser acceleration of bunches of energetic deuterons with a small energy spread at about 2 MeV. This quasimonoenergetic peak within the ion energy spectrum was observed when heavy-water microdroplets were irradiated with ultrashort laser pulses of about 40 fs duration and high (10(-8)) temporal contrast, at an intensity of 10(19) W/cm(2). The results can be explained by a simple physical model related to spatial separation of two ion species within a finite-volume target. The production of quasimonoenergetic ions is a long-standing goal in laser-particle acceleration; it could have diverse applications such as in medicine or in the development of future compact ion accelerators.

10.
Opt Lett ; 30(8): 923-5, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15865400

RESUMO

We demonstrate a double chirped-pulse-amplification (CPA) Ti: sapphire laser system that includes two CPA stages with intermediate nonlinear temporal pulse filtering. The method makes it possible to reduce substantially the background of amplified spontaneous emission (ASE), including prepulses and postpulses. An ASE temporal contrast of 10(10) was demonstrated at 20 mJ of output energy and 50-fs pulse duration. The demonstrated scheme is applicable to petawatt power-level laser systems.

11.
Phys Rev Lett ; 94(5): 053602, 2005 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-15783638

RESUMO

We have investigated atomic ionization dynamics in Kr in the transition regime from nonrelativistic to relativistic laser intensities (10(16) to 10(18) W/cm2) by measuring yields of highly charged ions stemming from an inner shell. Interpretation of the data is focused on the applicability of the single active electron description, which requires fully relaxed core states between successive ionization steps. In particular, we are concerned with transient core polarization or alignment effects originating from the strong dependence of the ionization rates on the magnetic quantum number. We found that for intense laser pulses with 40 fs pulse width internal m-mixing processes appear to be sufficiently fast to erase any transient core polarization.

12.
Opt Express ; 12(21): 5088-97, 2004 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-19484062

RESUMO

A nonlinear filter using rotation of the polarization ellipse in air is investigated. Scheme to enhance the temporal contrast is developed for a double-CPA multi-terawatt Ti:sapphire laser. It supports an energy level of millijoule and has a high efficiency. The method allows suppression of the ASE pedestal, pre- and post-pulses by 3 orders of magnitude and also steepens the pulse front. For the physical interpretation of the results, numerical simulation of the filtering is performed.

13.
Tsitol Genet ; 30(2): 67-74, 1996.
Artigo em Ucraniano | MEDLINE | ID: mdl-9281204

RESUMO

The review on the problem of human chromosomal polymorphism is presented. Biological nature of polymorphism of heterochromatin as well as its different phenotypes were considered. Prospects of chromosomal polymorphism study in the future for investigation of different forms of pathology were also discussed.


Assuntos
Cromossomos Humanos/genética , Polimorfismo Genético/genética , Heterocromatina/genética , Humanos , Fenótipo
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