Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Vestn Otorinolaringol ; 84(4): 22-24, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31579052

RESUMO

In this article were represented a clinical examination and assessment of the effectiveness of the open extracorporeal rhinoseptoplasty technique perfomed in W. Gubisch modification. For the analysis of the results, patients were divided on the basis of the indications for extracorporeal rhinoseptoplasty in major groups. Performed clinical example of multiple fractures of cartilage department of the septum.


Assuntos
Septo Nasal , Rinoplastia , Cartilagem/cirurgia , Humanos , Septo Nasal/cirurgia , Rinoplastia/métodos
2.
J Phys Condens Matter ; 29(3): 035003, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27845922

RESUMO

A theoretical and experimental study of the work function of few-layer graphene is reported. The influence of the number of layers on the work function is investigated in the presence of a substrate, a molecular dipole layer, and combinations of the two. The work function of few-layer graphene is almost independent of the number of layers with only a difference between monolayer and multilayer graphene of about 60 meV. In the presence of a charge-donating substrate the charge distribution is found to decay exponentially away from the substrate and this is directly reflected in the work function of few-layer graphene. A dipole layer changes the work function only when placed in between the substrate and few-layer graphene through a change of the charge transfer between the two.

3.
Phys Rev Lett ; 115(19): 196401, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26588400

RESUMO

The intrinsic field effect, the change in surface conductance with an applied transverse electric field, of prototypal strongly correlated VO(2) has remained elusive. Here we report its measurement enabled by epitaxial VO(2) and atomic layer deposited high-κ dielectrics. Oxygen migration, joule heating, and the linked field-induced phase transition are precluded. The field effect can be understood in terms of field-induced carriers with densities up to ∼5×10(13) cm(-2) which are trongly localized, as shown by their low, thermally activated mobility (∼1×10(-3) cm(2)/V s at 300 K). These carriers show behavior consistent with that of Holstein polarons and strongly impact the (opto)electronics of VO(2).

4.
Mol Biol (Mosk) ; 48(5): 850-8, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25842871

RESUMO

Earlier, a new class of compounds--amphiphilic derivatives of 1,3-diazaadamantanes, capable of facilitating the strand exchange in the system of short oligonucleotides was revealed. Longer hydrophobic side chains of 1,3-diazaadamantanes promoted stronger acceleration of the reaction. In this study, interaction with DNA of two 1,3-diazaadamantane derivatives containing different side chains was investigated by use of optical methods. Concentration of the investigated 1,3-diazaadamantans micelles formation were determined by the means of monitoring fluorescence intensity enhancement of 1-anilinonaphtalene-8-sulphonate probe; as well as the ranges of concentrations where the compounds/water mixtures existed as true solutions. 1,3-diazaadamantanes affinity to DNA was determined with Fluorescent Intercalator Displacement (FID) approach. Significant increase in hydrodynamic volume of short DNA hairpins in the complexes with 1,3-diazaadamantanes was revealed by estimation of the fluorescence polarization of ethidium bromide probe bound to the hairpins. Intermolecular association of DNA hairpins upon binding with 1,3-diazaadamantans was confirmed by Förster resonance energy transfer in system of an equimolar mixture of fluorescently labeled with Cy-3 and Cy-5 hairpins. In this study, the number of positive charges at 1,3-diazaadamantane derivatives containing side chains of different lengths was demonstrated to affect their affinity to DNA, whereas longer length of the hydrophobic side chains ensured more efficient interaction between the DNA duplexes that may facilitate, in particular, DNA strand exchange.


Assuntos
Adamantano/química , DNA/química , Naftalenossulfonato de Anilina/química , Etídio/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Interações Hidrofóbicas e Hidrofílicas , Substâncias Intercalantes/química , Micelas , Modelos Moleculares , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Espectrometria de Fluorescência
5.
Nanotechnology ; 22(39): 395202, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21891859

RESUMO

We investigate breakdown of carbon nanotube (CNT) interconnects induced by Joule heating in air and under high vacuum conditions (10(-5) mbar). A CNT with a diameter of 18 nm, which is grown by chemical vapor deposition to connect opposing titanium nitride (TiN) electrodes, is able to carry an electrical power up to 0.6 mW before breaking down under vacuum, with a corresponding maximum current density up to 8 × 10(7) A cm(-2) (compared to 0.16 mW and 2 × 10(7) A cm(-2) in air). Decoration with electrochemically deposited Ni particles allows protection of the CNT interconnect against oxidation and improvement of the heat release through the surrounding environment. A CNT decorated with Ni particles is able to carry an increased electrical power of about 1.5 mW before breaking down under vacuum, with a corresponding maximum current density as high as 1.2 × 10(8) A cm(-2). The Joule heating produced along the current carrying CNT interconnect is able to melt the Ni particles and promotes the formation of titanium carbon nitride which improves the electrical contact between the CNT and the TiN electrodes.

6.
Nanotechnology ; 21(48): 485401, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21051804

RESUMO

Discrete image-potential states (ISs) are revealed at double-walled carbon nanotubes by means of scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) in the distance-voltage z(V) spectroscopy mode. The nanotubes are supported by flat Au(111) substrates. Due to the high sensitivity of the hot IS electrons to local variations of the surface potential, they can be considered as a sensitive probe to investigate interactions with the supporting substrate and impurities or defects at the nanotube surface. ISs provide information on the local electronic structure as well as on the electron dynamics at supported nanotubes.

7.
Anesteziol Reanimatol ; (6): 7-12, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21400790

RESUMO

Pregnancy in patients with hypertension is considered in the spotlight of creation of general adaptation syndrome. According to evidence, when a stable hypertension in pregnant patients with hyper- and eukinetic types of haemodynamics is observed, the response of circulatory system and body fluid compartments has a moderate difference with normal. In pregnant patients with hypertension and a hypokinetic type of haemodynamics and pregnant patients with gestosis developed against the background of eukinetic type of hypertension, a physiological decrease of total peripheral resistance (TPR) is absent, which contributes into interstitial hyperhydration. In pregnant patients with gestosis developed against the background of hypokinetic type of haemodynamics, a pathological rise of TPR occurs, which is followed with a more significant interstitial hyperhydration. A differentiated preoperative preparation of pregnant with hypertension with the calcium antagonists and hydroxyethyl starch solution (130/0,4) favours the conversion of hyper- and hypokinetic types of haemodynamics to eukinetic, forms a physiological type of sympathicotonia and improves the water-salt metabolism.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Hemodinâmica/fisiologia , Hipertensão/tratamento farmacológico , Pré-Eclâmpsia/prevenção & controle , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Cuidados Pré-Operatórios/métodos , Adaptação Fisiológica , Sistema Nervoso Autônomo/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/uso terapêutico , Eletrocardiografia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Hemodinâmica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Hipertensão/fisiopatologia , Substitutos do Plasma/administração & dosagem , Pré-Eclâmpsia/fisiopatologia , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia
8.
Anesteziol Reanimatol ; (6): 17-22, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21400791

RESUMO

Pregnancy is considered in the spotlight of creation of general adaptation syndrome. It was revealed that 85% and 58% of healthy non-pregnant women had an inadequate autonomous nervous system (ANS) and circulatory system response respectively. This favoured the labour activity malfunction in 20% of women in childbirth when an abdominal delivery was needed. A traditional subarachnoid anesthesia (SA) in control group was accompanied by decrease of blood pressure (BP) to the numbers requiring a medicamentous correction (as by literature data). However, the central haemodynamics measures has shown a normal blood flow and the blood pressure correction was not performed. During surgery and in early post-operative period in all women in this group a parasympathetic tone has prevailed over, and the cardiac output was at the lower limit of the hypokinetic type of haemodynamics, which was accompanied with nausea and vomiting in 30% of women. Including the atropine administration into the traditional protocol of SA in cesarean section in pregnant patients with eu- and parasympathotonia (research group) has favoured the optimization of the neurovegetative inhibition of reflexes and stabilization of haemodynamics within the physiological ranges. Vagosympathetic block has been accompanied by sympathotonia with a lesser BP decrease compared to control group, absence of bradycardia, nausea and vomiting. Thus the BP can not serve as a criterion of the perfusion of essential organs, including uteroplacental haemodynamics, especially non-invasibe BP. Including the control of ANS tone dynamics, central haemodynamics and oxygen transport into monitoring guidelines in neuroaxial anaesthesia in abdominal delivery is necessary.


Assuntos
Anestesia Obstétrica/métodos , Raquianestesia/métodos , Sistema Nervoso Autônomo/fisiopatologia , Cesárea/métodos , Hemodinâmica/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Adjuvantes Anestésicos/uso terapêutico , Anestésicos Locais , Índice de Apgar , Atropina/uso terapêutico , Sistema Nervoso Autônomo/efeitos dos fármacos , Bupivacaína , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Recém-Nascido , Monitorização Intraoperatória/métodos , Substitutos do Plasma/administração & dosagem , Gravidez , Espaço Subaracnóideo
9.
Anesteziol Reanimatol ; (6): 13-7, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21404448

RESUMO

A differentiated administration of calcium antagonists in preoperative preparation of pregnant patients with hypertension enabled the conversion of circulatory system state to "normal pregnancy range": a conversion of hypokinetic (including the HES solution infusion) and hyperkinetic types of haemodynamics to eukinetic one, with the decrease of total peripheral resistance and myocardium need for oxygen, autonomous nervous system state to physiological sympathicotonia. Evidence shows that continued intra-operative treatment including tranexamic acid enables to maintain those results during the surgery. In postoperational period, the clinical manifestations of SIRS in patients who has received the mentioned therapy were marked less then in control group, and the newborns have a higher Apgar score.


Assuntos
Anestesia Obstétrica/métodos , Cesárea/métodos , Hemodinâmica/fisiologia , Hipertensão , Complicações Cardiovasculares na Gravidez , Cuidados Pré-Operatórios/métodos , Índice de Apgar , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiopatologia , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/uso terapêutico , Eletrocardiografia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Idade Gestacional , Hemodinâmica/efeitos dos fármacos , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Recém-Nascido , Substitutos do Plasma/administração & dosagem , Período Pós-Operatório , Gravidez , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/fisiopatologia
12.
Anesteziol Reanimatol ; (6): 8-13, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18326250

RESUMO

By taking into account the fact that the autonomic nervous and cardiovascular systems (ANS and CVS) are the major links of development of the general adaptation syndrome in pregnancy, which are affected by all the processes involved in the development of the syndrome, the author analyzed the state of these systems in healthy non-pregnant and pregnant women (HNPW and HPW) and in pregnant women with gestosis. HNPW were found to have already a prerequisite for impairing pregnancy adaptive processes as ANS and CVS dysfunction. In HPW, these impairments were more pronounced. In the pregnant women, impaired adaptive processes manifested themselves as excess sympathicotonia in 72% and parasympathicotonia in 23% of cases despite the treatment performed, which was accompanied by hypokinetic hemodynamics in 53 and 50%, respectively. In hyper- and eukinetic hemodynamics, there were no physiologically required decreases in total peripheral vascular resistance while in hypokinetic hemodynamics, there was its pathological increase. Such disorders enhance the significance of abdominal compartment syndrome, aortocaval compression, ischemia-reperfusion, hydrodynamic and membranogenic (capillary leakage) factors of impaired water metabolism, which contributes to adaptation derangement. Based on the findings, the authors have created a developmental modulation algorithm for the general adaptation syndrome by completed pregnancy and surgical delivery.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Síndrome de Adaptação Geral/etiologia , Hemodinâmica/fisiologia , Água/metabolismo , Adolescente , Adulto , Animais , Feminino , Síndrome de Adaptação Geral/metabolismo , Humanos , Gravidez
13.
Anesteziol Reanimatol ; (6): 41-5, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18326257

RESUMO

The paper analyzes the results of using in the anesthetic maintenance of pregnant females with gestosis the algorithm of preventing possible impairments in the development of the general adaptation syndrome in response to pregnancy and surgical labor. Calcium antagonists (eliminating dysfunction of secondary calcium messenger), ketonal, and tranexamic acid (which inhibiting a number of pain and inflammation mediators), and hydroxyethyl starch-130/04 solution (regenerating the endothelium) were administered to prevent the clinical manifestations of the intraabdominal compartment syndrome, ischemia-pefusion, and the second wave of the systemic inflammatory response syndrome in response to surgery. The differential use of the above agents at all stages of anesthetic maintenance in pregnant women with gestosis promoted the postoperative preservation of the most efficient eukinetic hemodynamics and physiological sympathicotonia and the elimination of water metabolic disturbances more early than in the control puerperas. A more physiological postoperative course in the study group puerperas called for much less pharmacotherapy, which created more favorable conditions for postoperative maternal-neonatal contact (feeding, etc.).


Assuntos
Anestesia Obstétrica/métodos , Cesárea , Síndrome de Adaptação Geral , Hemodinâmica , Pré-Eclâmpsia , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/efeitos adversos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Feminino , Síndrome de Adaptação Geral/etiologia , Síndrome de Adaptação Geral/prevenção & controle , Hemodinâmica/efeitos dos fármacos , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/efeitos adversos , Derivados de Hidroxietil Amido/uso terapêutico , Cetoprofeno/administração & dosagem , Cetoprofeno/efeitos adversos , Cetoprofeno/uso terapêutico , Período Pós-Operatório , Pré-Eclâmpsia/fisiopatologia , Gravidez , Ácido Tranexâmico/administração & dosagem , Ácido Tranexâmico/efeitos adversos , Ácido Tranexâmico/uso terapêutico
14.
Anesteziol Reanimatol ; (6): 57-9, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18326262

RESUMO

The paper describes a case from the practice of the maternity hospital, City Hospital Sixty-Seven. The pregnant woman at gestational weeks 36-37 was found to have a brain tumor complicated by obstructive hydrocephalus and dislocation syndrome. Ventriculoperitoneal bypass and abdominal delivery were simultaneously performed under endotracheal anesthesia using propofol, nitrous oxide, and small-dose ketamine (25 mg), and after fetal extraction, fentanyl. At minutes 1 and 5, the Apgar score of the neonate was 8 and 8, respectively. The patient was discharged from the hospital in satisfactory condition on day 7 postoperatively and it was recommended that her surgical treatment at a neurosurgical clinic be decided.


Assuntos
Neoplasias Cerebelares/cirurgia , Cesárea , Serviços Médicos de Emergência , Complicações Neoplásicas na Gravidez/cirurgia , Derivação Ventriculoperitoneal , Adulto , Neoplasias Cerebelares/diagnóstico , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico , Resultado da Gravidez , Resultado do Tratamento
15.
Anesteziol Reanimatol ; (6): 4-8, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18330018

RESUMO

Based on their own findings and the data available in the literature on pregnancy including that complicated by gestosis, the authors consider these conditions in the context of Selye's general adaptation syndrome. They identify its basic links (the autonomic nervous and cardiovascular systems) the function of which is affected by all the physiological and pathophysiological processes involved in its development. There is a high likelihood of baseline impaired adaption processes in these links, which may lead to an inability to accommodate (dysadaptation) by the moment of delivery. The paper gives the current interpretation of functional disorders, called Zangemeister'a triad in 1913, from the present-day points of view of the evaluation of pregnancy as the systemic inflammatory response syndrome and, probably, adaptation disease. Based on the results of analyzing the data available in the literature, the authors indicate physiologically the basic trends in the modulation of impaired development processes of the general adaptation syndrome towards the completion of pregnancy and surgical delivery.


Assuntos
Adaptação Fisiológica , Síndrome de Adaptação Geral , Sistema Nervoso Autônomo/fisiologia , Catecolaminas/metabolismo , Feminino , Síndrome de Adaptação Geral/etiologia , Síndrome de Adaptação Geral/imunologia , Síndrome de Adaptação Geral/metabolismo , Glucocorticoides/metabolismo , Hemodinâmica/fisiologia , Humanos , Pré-Eclâmpsia/etiologia , Pré-Eclâmpsia/imunologia , Pré-Eclâmpsia/metabolismo , Gravidez
16.
Anesteziol Reanimatol ; (6): 20-4, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18330020

RESUMO

Differential preoperative preparation of pregnant women with gestosis, which is aimed at eliminating dysfunction of the universal secondary calcium messenger and preventing further disorders caused by calcium antagonists, is accompanied by positive changes in the basic links of development of the general adaptation syndrome--the autonomic nervous and cardiovascular systems. A physiologically required reduction in total peripheral vascular resistance (TPVE) is achieved in pregnant women with hyper- and eukinetic hemodynamics. In pregnant women with hypokinetic type, who receive hydroxyethyl starch-130/04 solution in the infusion therapy protocol, there is elimination of its pathological increase and there is a tendency for its physiological reduction. Obviating the discrepancy between cardiac index and TPVE causes a change of the hyper- and hypokinetic hemodynamic types to the eukinetic one, which is attended by development of physiological sympathicotonia and by almost complete normalization of water metabolic parameters in pregnant women with gestosis.


Assuntos
Bloqueadores dos Canais de Cálcio/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Pré-Eclâmpsia/tratamento farmacológico , Cuidados Pré-Operatórios/métodos , Adolescente , Adulto , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiopatologia , Bloqueadores dos Canais de Cálcio/administração & dosagem , Feminino , Humanos , Pré-Eclâmpsia/fisiopatologia , Gravidez , Resultado do Tratamento
17.
J Colloid Interface Sci ; 286(2): 632-8, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15897082

RESUMO

Determination of the surface roughness by AFM is crucial to the study of particle fouling in nanofiltration. It is, however, very difficult to compare the different roughness values reported in the literature because of a lack in uniformity in the methods applied to determine surface roughness. AFM is used in both noncontact mode and tapping mode; moreover, the size of the scan area is highly variable. This study compares, for six different nanofiltration membranes (UTC-20, N30F, Desal 51HL, Desal 5DL, NTR7450, NF-PES-10), noncontact mode AFM with tapping mode AFM for several sizes of the scan area. Although the absolute roughness values are different for noncontact AFM and tapping mode AFM, no difference is found between the two modes of AFM in ranking the nanofiltration membranes with respect to their surface roughness. NTR 7450 and NF-PES-10 are the smoothest membranes, while the roughest surface can be found with Desal 51HL and Desal 5DL. UTC-20 and N30F are characterized by an intermediate roughness value. An increase in roughness with increasing scan area is observed for both AFM modes. Larger differences between the roughnesses of the membranes are obtained with tapping mode AFM because of the tapping of the tip on the surface. Phase imaging is an extension of tapping mode AFM, measuring the phase shift between the cantilever oscillation and the oscillation of the piezo driver. This phase shift reflects the interaction between the cantilever and the membrane surface. A comparison with contact angle measurements proves that a small phase shift corresponds to a large contact angle, representing a hydrophobic membrane surface.

20.
Res Microbiol ; 152(5): 503-14, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11446519

RESUMO

We have studied the mechanisms of the horizontal dissemination of a broad-spectrum mercury resistance determinant among Bacillus and related species. This mer determinant was first described in Bacillus cereus RC607 from Boston Harbor, USA, and was then found in various Bacillus and related species in Japan, Russia and England. We have shown that the mer determinant can either be located at the chromosome, or on a plasmid in the Bacillus species, and is carried by class II mercury resistance transposons: Tn5084 from B. cereus RC607 and B. cereus VKM684 (ATCC10702) and Tn5085 from Exiguobacterium sp. TC38-2b. Tn5085 is identical in nucleotide sequence to TnMERI1, the only other known mer transposon from Bacillus species, but it does not contain an intron like TnMERI1. Tn5085 is functionally active in Escherichia coli. Tn5083, which we have isolated from B. megaterium MK64-1, contains an RC607-like mer determinant, that has lost some mercury resistance genes and possesses a merA gene which is a novel sequence variant that has not been previously described. Tn5083 and Tn5084 are recombinants, and are comprised of fragments from several transposons including Tn5085, and a relative of a putative transposon from B. firmus (which contains similar genes to the cadmium resistance operon of Staphylococcus aureus), as well as others. The sequence data showed evidence for recombination both between transposition genes and between mer determinants.


Assuntos
Bacillus/efeitos dos fármacos , Bacillus/genética , Elementos de DNA Transponíveis , Mercúrio/farmacologia , Fatores R , Bacillus/enzimologia , Sequência de Bases , Cromossomos Bacterianos , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Dados de Sequência Molecular , Óperon , Oxirredutases/genética , Mapeamento por Restrição , Especificidade da Espécie , Microbiologia da Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...