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1.
Her Russ Acad Sci ; 91(4): 419-427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539148

RESUMO

This July marks the 100th anniversary of the founding of the Chinese Communist Party. This event motivated the authors of this article to consider the main problems that modern Chinese society is solving, the place of the PRC in the world economy and politics at the beginning of the third decade of the 21st century, and China's growing influence on the planet. China's undoubted successes, including in the fight against the coronavirus pandemic and in overcoming the recession caused by tough quarantine measures in early 2020, show the considerable viability of the state created by the Chinese communists, which is increasingly at the forefront of the world in the economy, science and technology, and culture. However, the path to the current rise of the great power was by no means an easy one, and the prospects for its development are perhaps one of the most debated issues in international discussions. China never tires of emphasizing the specifics of its history. At the same time, the diversity of the internal conditions of the colossal country together with the skillful application of carefully studied foreign experience yielded the extraordinary wealth of forms of development, which can serve as a guarantee of new achievements and, possibly, useful universals for all humankind.

2.
ACS Biomater Sci Eng ; 6(8): 4397-4400, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-33455174

RESUMO

This paper is the continuation of our previous work on the ability of biocomposites based on sol-gel alumina (boehmite) to promote skin recovery from burns and atrophic scars. The present study describes the increasing of the cytoplasma volume and the number of filopodias of HDF cells, which for the first time indicates their proliferation on the alumina itself and on alumina-based biocomposite. Studies in vivo confirm the efficiency of the composite in the treatment of atrophic scars.


Assuntos
Óxido de Alumínio , Fibroblastos , Humanos
3.
Cell Biochem Biophys ; 77(1): 33-46, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30191452

RESUMO

In this overview, we present the results of the study of spleen and liver tissues taken from healthy donors in comparison with those from patients with (i) non-Hodgkin B-cell lymphomas, namely, mantle cell lymphoma and marginal zone B-cell lymphoma, (ii) acute myeloid leukemia, and (iii) primary myelofibrosis. The study was carried out using Mössbauer spectroscopy and magnetization measurements for the analysis of ferritin-like iron in spleen and liver tissues. Magnetization measurements demonstrated small differences in the saturation magnetic moments and revealed additional paramagnetic components. Two liver samples demonstrated unusual behavior of the magnetic moment when the zero-field-cooled curve was over the field-cooled curve in the temperature range between ~40 and ~70 K. Relative iron content variations in the tissue cells as well as small variations in the 57Fe hyperfine parameters were demonstrated for healthy and patients' spleen and liver tissues on the base of measured Mössbauer spectra. The results obtained permit us to suggest small differences in the ferritin iron core structure in spleen and liver tissues from healthy donors and patients with hematological malignancies.


Assuntos
Neoplasias Hematológicas/patologia , Ferro/química , Fígado/química , Espectroscopia de Mossbauer , Baço/química , Ferritinas/química , Humanos , Leucemia Mieloide Aguda/patologia , Fígado/metabolismo , Linfoma de Células B/patologia , Magnetismo , Microscopia , Mielofibrose Primária/patologia , Baço/metabolismo , Temperatura
4.
Chem Soc Rev ; 45(19): 5408-5431, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27711673

RESUMO

The last five years have witnessed a huge breakthrough in the creation and the study of the properties of a new class of compounds - metamaterials. The next stage of this technological revolution will be the development of active, controllable, and non-linear metamaterials, surpassing natural media as platforms for optical data processing and quantum information applications. However, scientists are constantly faced with the need to find new methods that can ensure the formation of quantum and non-linear metamaterials with higher resolution. One such method of producing metamaterials in the future, which will provide scalability and availability, is chemical synthesis. Meanwhile, the chemical synthesis of organized 3D structures with a period of a few nanometers and a size of up to a few millimeters is not an easy task and is yet to be resolved. The most promising avenue seems to be the use of highly porous structures based on metal-organic frameworks that have demonstrated their unique properties in the field of non-linear optics (NLO) over the past three years. Thus, the aim of this review is to examine current progress and the possibilities of using metal-organic frameworks in the field of non-linear optics as chemically obtained metamaterials of the future. The review begins by presenting the theoretical principles of physical phenomena represented by mathematical descriptions for clarity. Major attention is paid to the second harmonic generation (SHG) effect. In this section we compare inorganic single crystals, which are most commonly used to study the effect in question, to organic materials, which also possess the required properties. Based on these data, we present a rationale for the possibility of studying the non-linear optical properties of metal-organic structures as well as describing the use of synthetic approaches and the difficulties associated with them. The second part of the review explicitly acquaints the reader with a new class of materials which successfully combines the positive properties of organic and inorganic materials. Using recently synthesized metal-organic frameworks and coordination polymers in the field of non-linear optics as an example, we consider synthetic approaches used for obtaining materials with desired properties and the factors to be considered in this case. Finally, probable trends towards improving the quality of the synthesized materials with regards to their further use in the field of non-linear optical effects are described.

5.
Dalton Trans ; 45(17): 7244-9, 2016 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-26906040

RESUMO

A highly stable metal-organic framework, [{Fe3(ACTBA)2}X·6DEF]n (1; X = monoanion), based on trinuclear iron(iii) secondary building units connected by tetracarboxylates with an anthracene core, 2,6,9,10-tetrakis(p-carboxylatophenyl)anthracene (ACTBA), is reported. Depending on the direction of light polarisation, crystals of 1 exhibit anisotropic optical properties with birefringence Δn = 0.3 (λ = 590 nm).

6.
Urologiia ; (2): 16-9, 2014.
Artigo em Russo | MEDLINE | ID: mdl-24956665

RESUMO

The potentials for the use of free buccal mucosa graft in reconstruction plastic surgery of extended uretral stricture are evaluated. From 2007 to 2013, 9 operations in 8 patients (mean age 54,5+/-7,2 years) were performed. The average length of cicatricial uretral stricture was 5,1+/-0,7 cm. 1 patient has lesion in the upper third of the ureter, 4 patients - in the middle portion, and 4 patients - at the bottom portion. The causes of extended uretral stricture were following: long standing calculi (n=3), ureteral injury after ureterolithotripsy (n=2) and after bringing down the calcuus using loop (n=1), radiotherapy (n=3, one patient had bilateral injury). All patients underwent plastic reconstruction of ureter using buccal mucosa graft by "on-lay" type. During the follow-up (median, 42 months, from 3 to 72 months), in 7 (88,9 %) of 8 patients (8 operations) ureteral strictures relapses were not observed. They all had satisfactory renal excretory function without the pronounced violations of passage of urine along the ureter. The excretory urography showed moderate expansion of the ureter at the site of operation in 6 of them. Due to the progression of secondary renal scarring, one patient underwent nephrectomy 1.5 year after reconstruction plastic surgery. In this patient, pronounced anatomical and functional changes in the kidney occurred before the operation. Application of the buccal mucosa graft in reconstruction plastic surgery in extended uretral stricture is high effective due to the relatively low level of early and late postoperative complications and low recurrence rate.


Assuntos
Mucosa Bucal/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Cálculos Ureterais/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Cálculos Ureterais/patologia
7.
Biometals ; 26(2): 229-39, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23460118

RESUMO

Comparative study of human liver ferritin and spleen tissues from healthy human and patient with primary myelofibrosis was carried out using Mössbauer spectroscopy with a high velocity resolution at 295 and 90 K and with a low velocity resolution at 20 K. The results obtained demonstrated that the iron content in patient's spleen in the form of iron storage proteins was about ten times larger than that in normal tissue. However, in the case of patient with primary myelofibrosis the magnetic anisotropy energy barrier differed from that in normal case and, probably, the iron core size was supposed to be slightly larger than that in both normal spleen tissue and normal human liver ferritin in contrast to well-known data for iron overload in patients with thalassemia accompanied by the iron-core size increase. Therefore, the iron overload in the case of patient with primary myelofibrosis may be related to increase in the ferritin content mainly. It was also found that Mössbauer hyperfine parameters for normal and patient's spleen and normal human liver ferritin demonstrated some small differences related, probably, to some small structural variations in the ferritin iron cores of patient's spleen.


Assuntos
Ferritinas/metabolismo , Ferro/metabolismo , Mielofibrose Primária/metabolismo , Ferritinas/isolamento & purificação , Humanos , Ferro/isolamento & purificação , Fígado/metabolismo , Fígado/patologia , Mielofibrose Primária/patologia , Espectroscopia de Mossbauer , Baço/metabolismo , Baço/patologia
8.
Zh Nevrol Psikhiatr Im S S Korsakova ; 112(7 Pt 2): 24-8, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23330188

RESUMO

Spasticity in children cerebral palsy has its own peculiarities due to the presence of pathological tonic reflexes, pathological sinkinetic activity during arbitrary movements, disturbance of coordinative interactions of muscle synergists and antagonists, increase of total reflex excitability. Physiotherapeutic methods, massage, therapeutic exercises, kinesitherapy, biological feedback training (BFT), methods of orthopedic correction, neurosurgery are widely used in the treatment of spasticity. The use of botulinum toxin type A is a new effective approach to the treatment of spasticity that improves motor functions and quality of life of children with children cerebral palsy. It is being used in the treatment of children and adolescence in a polyclinic unit of the Moscow psychoneurological hospital since 2001. The experience of treatment with botulinum and wide implementation of this method indicated that botulinum toxin injections in the complex treatment of spasticity allow to optimize approaches to treatment of children and adolescence with children cerebral palsy and to increase significantly the quality of medical-social rehabilitation of patients.


Assuntos
Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/terapia , Antidiscinéticos/uso terapêutico , Baclofeno/uso terapêutico , Toxinas Botulínicas/uso terapêutico , Criança , Pré-Escolar , Humanos , Lactente , Relaxantes Musculares Centrais/uso terapêutico , Espasticidade Muscular/diagnóstico , Espasticidade Muscular/tratamento farmacológico , Espasticidade Muscular/terapia , Modalidades de Fisioterapia , Tolperisona/uso terapêutico
9.
Zh Nevrol Psikhiatr Im S S Korsakova ; 112(7 Pt 2): 34-40, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23330190

RESUMO

The review is devoted to main neurosurgical approaches to the treatment of the spasticity syndrome in children cerebral palsy. Neurosurgical procedures are divided into destructive and neuromodulating. The former included posterior selective rhizotomy, selective neurotomy and destructive operations on subcortical brain structures. The latter group included electrostimulation of brain and spinal cord structures and implantation of pumps for the chronic intrathecal baclofen (lioresal) infusion. Each method is considered in a historical aspect. Details of clinical application, positive and negative sides of the methods are described.


Assuntos
Paralisia Cerebral/cirurgia , Espasticidade Muscular/cirurgia , Criança , Implantes de Medicamento/uso terapêutico , Terapia por Estimulação Elétrica , Eletrodos Implantados , Humanos , Músculo Esquelético/inervação , Músculo Esquelético/cirurgia , Procedimentos Neurocirúrgicos/classificação , Rizotomia , Síndrome
10.
Zh Nevrol Psikhiatr Im S S Korsakova ; 112(7 Pt 2): 41-6, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23330191

RESUMO

Anesthesia in surgical treatment and anesthetization in post operative period in patients with children cerebral palsy (CCP) is considered as an actual problem due to some specific features. The authors review the current state of the problem in aspects of efficacy and setting priorities in the development of methods of anesthesia in patients with CCP. Some methods of anesthesia, positive and negative sides of their application in CCP are characterized.


Assuntos
Anestesia/métodos , Paralisia Cerebral/cirurgia , Anestesia/efeitos adversos , Paralisia Cerebral/fisiopatologia , Criança , Humanos , Período Pré-Operatório
11.
Zh Nevrol Psikhiatr Im S S Korsakova ; 112(7 Pt 2): 56-63, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23330194

RESUMO

Neurological diseases, mental disorders and inherited developmental abnormalities held a prominent place in the structure of primary children disability. Children cerebral palsy is the main cause of children disability, its prevalence reaching 2-3.5 cases per 1000 children. This disease has the noticeable negative consequences (both clinical and economic). Adherence to treatment means patient's compliance with doctor's orders including taking medicines as prescribed, sticking to diet and changing life style habits. While the adult patient plays an active role in doctor-patient alliance, the child patient interacts with the doctor together with his/her family. The authors consider the effect of different factors on the adherence basing on the analysis of 270 questionnaires completed by persons involved in the treatment of minor patients.


Assuntos
Cuidadores/psicologia , Paralisia Cerebral/reabilitação , Família/psicologia , Cooperação do Paciente , Paralisia Cerebral/diagnóstico , Paralisia Cerebral/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Moscou/epidemiologia , Prevalência , Inquéritos e Questionários
12.
Biometals ; 24(3): 501-12, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21350949

RESUMO

A comparative study of oxyhemoglobins from pig, rabbit, normal human and patients with blood system malignant diseases was performed using Mössbauer spectroscopy with a high velocity resolution at 90 K. Mössbauer spectra were fitted with the help of two models: using one quadrupole doublet (model of equivalent iron electronic structure in α- and ß-subunits of hemoglobins) and superposition of two quadrupole doublets (model of non-equivalent iron electronic structure in α- and ß-subunits of hemoglobins). The results obtained using both models demonstrated small variations of hyperfine parameters that were related to the heme iron state variation in different hemoglobins. These results were compared with structural and functional differences of the hemoglobins investigated.


Assuntos
Heme/química , Hemoglobinas/química , Ferro/química , Oxiemoglobinas/química , Espectroscopia de Mossbauer/métodos , Animais , Doenças Hematológicas/fisiopatologia , Humanos , Subunidades Proteicas/química , Coelhos , Suínos
13.
Micron ; 41(7): 722-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20637640

RESUMO

The high transparency of carbon-containing materials in the spectral region of "carbon window" (lambda approximately 4.5-5nm) introduces new opportunities for various soft X-ray microscopy applications. The development of efficient multilayer coated X-ray optics operating at the wavelengths of about 4.5nm has stimulated a series of our imaging experiments to study thick biological and synthetic objects. Our experimental set-up consisted of a laser plasma X-ray source generated with the 2nd harmonics of Nd-glass laser, scandium-based thin-film filters, Co/C multilayer mirror and X-ray film UF-4. All soft X-ray images were produced with a single nanosecond exposure and demonstrated appropriate absorption contrast and detector-limited spatial resolution. A special attention was paid to the 3D imaging of thick low-density foam materials to be used in design of laser fusion targets.


Assuntos
Microanálise por Sonda Eletrônica/métodos , Processamento de Imagem Assistida por Computador/métodos , Animais , Vasos Sanguíneos/ultraestrutura , Dípteros/ultraestrutura , Humanos , Pâncreas/ultraestrutura
15.
Appl Opt ; 48(12): 2267-74, 2009 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-19381177

RESUMO

We propose and study both numerically and experimentally a feedback-controlled laser system capable of generating regular bursts with a submicrosecond period. Bursting is obtained in a laser that is controlled by a combination of feedbacks in which the negative feedback loop action is delayed by one cavity round trip with respect to the positive one, and the period is adjusted by relative feedback sensitivity. The proper combination of feedbacks is realized in a Nd:YAG laser with millisecond pumping by means of a single optoelectronic negative feedback unit that utilizes the signal reflected from an intracavity Pockels cell polarizer. Regular bursting (microgroups of picosecond pulses) with controlled periods from 25 to 75 cavity round trips is obtained experimentally. The development of chaotic dynamics displayed by the system at a higher pumping level differs from the Feigenbaum scenario.

16.
Rev Sci Instrum ; 79(10): 10F542, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044684

RESUMO

New extreme ultraviolet (EUV) spectroscopic diagnostics of relatively low-temperature plasmas based on the application of an EUV spectrometer and fast EUV diodes combined with glass capillary optics is described. An advanced high resolution dispersive element sliced multilayer grating was used in the compact EUV spectrometer. For monitoring of the time history of radiation, filtered fast EUV diodes were used in the same spectral region (>13 nm) as the EUV spectrometer. The radiation from the plasma was captured by using a single inexpensive glass capillary that was transported onto the spectrometer entrance slit and EUV diode. The use of glass capillary optics allowed placement of the spectrometer and diodes behind the thick radiation shield outside the direction of a possible hard x-ray radiation beam and debris from the plasma source. The results of the testing and application of this diagnostic for a compact laser plasma source are presented. Examples of modeling with parameters of plasmas are discussed.

17.
Stomatologiia (Mosk) ; 87(2): 73-5, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18454124

RESUMO

Multiple processes in economics reflect in management and corporative culture of any institution. Long-term motivational influence plays main role in the motivation mechanism; in turn motives form stable and long-term acting system integrated into corporative culture of any stomatological institution. Integration of the interests of the institution and separate members of the staff becomes the basic condition of the interested attitude to work.


Assuntos
Ética Clínica , Relações Interprofissionais/ética , Medicina Bucal/ética , Inquéritos e Questionários/normas , Humanos
18.
Appl Opt ; 46(23): 5964-6, 2007 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-17694150

RESUMO

A new cost-efficient sputter-slice technology for hard x-ray (10-30 keV) Fresnel zone plates fabrication, imposing no limitation to aspect ratio, is proposed. By means of a plasma chemical process, SiO(2)/Si(1-x)Ge(x)O(2) glassy film multilayer structures are deposited on a lateral surface of a silica rod, outermost layers being as thin as 100 nm. It has been shown by numerical simulation that for x=0.2 germanium fraction, 100-300 microm zone plate thickness and the number of zones of about 1000, first order diffraction efficiency as high as 20%-30% at the energy of approximately 20 keV can be achieved.

19.
Opt Lett ; 32(10): 1202-4, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17440534

RESUMO

It is found that the reflection of leaky radiation from the interface between the outer silica cladding and the coating polymer greatly modifies the loss spectrum of Bragg fibers. A simple model that describes this effect is proposed and confirmed by measurement and computation.

20.
Opt Lett ; 30(16): 2095-7, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16127921

RESUMO

Images with a spatial resolution of 120-150 nm were obtained with 46.9 nm light from a compact capillary-discharge laser by use of the combination of a Sc-Si multilayer-coated Schwarzschild condenser and a free-standing imaging zone plate. The results are relevant to the development of compact extreme-ultraviolet laser-based imaging tools for nanoscience and nanotechnology.


Assuntos
Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Lasers , Microscopia Confocal/instrumentação , Nanotecnologia/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Raios Ultravioleta , Desenho de Equipamento , Análise de Falha de Equipamento , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/instrumentação , Microscopia Confocal/métodos , Nanotecnologia/métodos
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