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OBJECTIVE: To evaluate the effectiveness of intraoperative angiography and fluorescence navigation with indocyanine green in reducing the risks of intra- and postoperative complications, as well as resection quality in patients with gastric cancer. MATERIAL AND METHODS: The main group consisted of patients who underwent intraoperative angiography and fluorescence navigation with indocyanine green (n=43). The control group included patients without these procedures (n=154). Both groups did not differ in gender (p=0.937) and age (p=0.437). The lower third of the stomach was the most common tumor location in the main group (62.7% of cases), the middle and lower thirds of the stomach - in the control group (37% and 38.9% of patients, respectively). There was no between-group difference in «cT¼ grading (p>0.05). However, there were more «cN+¼ patients in the main group (14 (32.6%) versus 28 (18.4%) ones of «N0¼ category, p=0.042). Therefore, 41.9% and 13.6% of patients underwent neoadjuvant chemotherapy in both groups, respectively (<0.001). RESULTS: Intraoperative angiography and fluorescence navigation with indocyanine green does not increase mortality (p=0.631), incidence of major (CD 3-5) (p=0.436) and minor (CD 1-2) postoperative complications (p=0.177), surgery time (p=0.288), mean intraoperative blood loss (p=0.144) and length of hospital-stay (p=0.631). Fluorescence navigation with indocyanine green does not affect the number of detected «positive¼ resection margins (R1) (p=0.883) but significantly increases the number of excised lymph nodes (p<0.001). CONCLUSION: Intraoperative angiography and fluorescence navigation with indocyanine green are safe for intraoperative visualization of tumor and lymph nodes, as well as assessment of arterial blood supply. This technique is effective in traditional and minimally invasive surgeries for gastric cancer. Fluorescence navigation with indocyanine green significantly increases the number of excised lymph nodes.
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Laparoscopía , Neoplasias Gástricas , Humanos , Verde de Indocianina , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Fluorescencia , Gastrectomía/efectos adversos , Gastrectomía/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/cirugía , Laparoscopía/métodosRESUMEN
INTRODUCTION: Rabbit hemorrhagic disease is an acute highly contagious infection associated with two genotypes of pathogenic Lagovirus. Antibodies to major capsid protein (Vp60) are protective. The aim of the work â is an evaluation of antigenic and immunogenic activity of virus-like particles (VLPs) based on recombinant major capsid proteins of both genotypes of rabbit hemorrhagic disease virus (RHDV) (recVP60-GI1 and recVP60-GI2). MATERIALS AND METHODS: Baculovirus-expressed VLPs were evaluated using electron microscopy and administered to clinically healthy 1.53 month old rabbits in a dose of 50 g. Rabbits were challenged with 103 LD50 of virulent strains Voronezhsky-87 and Tula 21 days post immunization. Serum samples were tested for the presence of RHDV-specific antibodies. RESULTS: VLPs with hemagglutination activity forming VLP 3040 nm in size were obtained in Hi-5 cell culture. Specific antibody titers in rabbits measured by ELISA were 1 : 200 to 1 : 800 on 21th day post immunization with VLPs. Immunogenic activity of recVP60-GI1 VLPs was 90 and 40%, while it was 30 and 100% for recVP60-GI2 VLPs after the challenge with RHDV genotypes 1 and 2 respectively. The immunogenicity of two VLPs in mixture reached 100%. DISCUSSION: VLPs possess hemagglutinating, antigenic and immunogenic activity, suggesting their use as components in substances designed for RHDV specific prophylaxis in rabbits. Results of the control challenge experiment demonstrated the need to include the antigens from both RHDV genotypes in the vaccine. CONCLUSION: Recombinant proteins recVP60-GI1 and recVP60-GI2 form VLPs that possess hemagglutinating an antigenic activity, and provide 90100% level of protection for animals challenged with RHDV GI1 and GI2 virulent strains.
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Caliciviridae , Virus de la Enfermedad Hemorrágica del Conejo , Lagovirus , Animales , Conejos , Virus de la Enfermedad Hemorrágica del Conejo/genética , Proteínas de la Cápside/genética , Proteínas Recombinantes/genéticaRESUMEN
This review presents the current state of the problem of development and application of the specific prevention of African swine fever (ASF) with a brief description of its etiology and pathogenesis. The unique nature of the ASF virus (ASFV) determines some limitations and the complexity of solving the problem of vaccine development. Such situation stimulated the development of highly specific diagnostic methods for rapid and accurate detection of the ASFV. In this regard, results of studies, including our own, concerning the comparative analysis of the genome of vaccine and virulent strains of the ASFV, as well as immunodiagnostic approaches to determine causes of high virulence and low protective activity of the ASFV, are briefly presented. Special attention is given to the issue related to the development of safe and effective vaccines against ASF. In this context disadvantages and possible advantages of live attenuated (LAV) and recombinant (RV) vaccines are considered in details. Results of recent studies on the assessment of the immunogenicity of genetically modified vaccines (GMV) which developed in various laboratories around the world are presented. The obtained data indicate that ASF vaccination is currently the most promising measure to stop the spread of this disease in our country and in the world, however, previous experience with ASF vaccination has revealed some problems in its development and application. The significant contribution of foreign researchers to the study of the basics of virulence of this pathogen and the study of its genes functions are noted. The possible further expansion of ASF in Europe and Asia in bordering Russia territories, as well as the established fact of the persistence of ASFV in wild boar population indicate a constant threat of its re-introduction into our country. In conclusion, the importance of developing a safe effective vaccine against ASF and the assessing of the possible risks of creating the artificial sources of the infection in nature as a result of its use is emphasized.
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Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Vacunas Virales , Fiebre Porcina Africana/epidemiología , Fiebre Porcina Africana/prevención & control , Animales , Federación de Rusia/epidemiología , Porcinos , VirulenciaRESUMEN
Beyond fifth generation (5G) communication systems aim towards data rates in the tera bits per second range, with improved and flexible coverage options, introducing many new technological challenges in the fields of network architecture, signal pro- cessing, and radio frequency front-ends. One option is to move towards cell-free, or distributed massive Multiple-Input Multiple-Output (MIMO) network architectures and highly integrated front-end solutions. This paper presents an outlook on be- yond 5G distributed massive MIMO communication systems, the signal processing, characterisation and simulation challenges, and an overview of the state of the art in millimetre wave antennas and electronics.
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INTRODUCTION: Rotavirus infection is the leading cause of acute gastroenteritis among infants. The development of new vaccines against rotavirus A is urgent because the virus has many genotypes, some of which have regional prevalence. Virus-like particles (VLP) is a promising way to create effective and safe vaccine preparations.The purpose of the study is to develop the technology for the production of VLP, containing VP2, VP4, VP6 and VP7 of viral genotypes prevalent on the territory of the Russian Federation, and to give its molecular genetic and virological characteristics. MATERIAL AND METHODS: The virulent strain Wa G1P[8] of human RV A adapted to MARC-145 cell culture has been used. It was cultured and purified according to the method described by the authors earlier. Standard molecular genetic and cytological methods were used: gene synthesis; cloning into transfer plasmids; recombinant baculoviruses production in Bac-to-Bac expression system; VLP production in the insect cells; centrifugation in sucrose solution; enzyme-linked immunosorbent assay (ELISA); electron microscopy (EM); polyacrylamide gel electrophoresis (SDS-PAGE) and western blot analysis. RESULTS: VP4 and VP7 of the six most represented in Russia genotypes: G1, G2, G4, G9, P4, P8, as well as VP2 and VP6 were selected for VLP production. Recombinant baculoviruses were obtained with codon frequencies optimized for insect cells. Cabbage loopper (Trichoplusia ni) cell culture was coinfected with different combinations of baculoviruses, and VLP consisting of 2-4 proteins were produced. VLP were purified by centrifugation. The size and morphology of the particles matched the rotavirus A virion (by EM). The presence of rotavirus A proteins in VLP was confirmed by the ELISA, SDS-PAGE and western blot analysis. CONCLUSION: The technology for the synthesis of three-layer VLP consisting of VP2, VP4, VP6 and VP7 has been developed and optimized. The resulting VLP composition represents 6 serotypes of VP4 and VP7, which are most represented on the territory of Russia, and can be used for vaccine development.
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Reoviridae , Infecciones por Rotavirus , Rotavirus , Humanos , Rotavirus/genética , Desarrollo de Vacunas , ViriónRESUMEN
The review presents the state-of-the-art on the problem of diagnosis of prion diseases (PD) in humans and animals with a brief description of their etiology and pathogenesis. We pointed out that understanding the nature of the etio logical agent of PD determined their zoonotic potential and led to the development of highly specific immunological diagnostic methods aimed at identifying the infectious isoform of prion protein (PrPd) as the only marker of the disease. In this regard, we briefly summarize the results of studies, including our own, concerning the conversion of normal prion protein molecules (PrPc) to PrPd, the production of monoclonal antibodies and their application as immunodiagnostic reagents for the post-mortem detection of PrPd in various formats of immunoassay. We also emphasize the issues related to the development of methods for ante mortem diagnostics of PD. In this regard, a method for amplifying amino acid sequences using quacking-induced conversion of PrPc to PrPd in real time (RTQuIC) described in details. The results of recent studies on the assessment of the sensitivity, specificity and reproducibility of this method, carried out in various laboratories around the world, are presented. The data obtained indicate that RT-QuIC is currently the most promising laboratory assay for detecting PrPd in biological material at the preclinical stage of the disease. The significant contribution of US scientists to the introduction of this method into clinical practice on the model of diagnosis of chronic wasting disease of wild Cervidae (CWD) is noted. The possible further spread of CWD in the population of moose and deer in the territories bordering with Russia, as well as the established fact of alimentary transmission of CWD to macaques, indicate the threat of the appearance of PD in our country. In conclusion, the importance of developing new hypersensitive and/or selective components of known methods for PrPd identification from the point of view of assessing the risks of creating artificial infectious prion proteins in vivo or in vitro, primarily new pathogenic isoforms ("strains") and synthetic prions, was outlined.
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Autopsia , Enfermedades por Prión/diagnóstico , Proteínas Priónicas/genética , Enfermedad Debilitante Crónica/genética , Secuencia de Aminoácidos/genética , Animales , Ciervos/genética , Humanos , Enfermedades por Prión/genética , Enfermedades por Prión/patología , Proteínas Priónicas/aislamiento & purificación , Federación de Rusia , Enfermedad Debilitante Crónica/patologíaRESUMEN
BACKGROUND: Rоtaviruses are amоng the leading causes of severe diarrhea in children all over the Wоrld. Vaccination is considered to be the mоst effective way to cоntrоl the disease. Currently available vaccines for prevention of rоtavirus infection are based on live attenuated rotavirus strains human оr animal origin. OBJECTIVES: The aim of this investigation was to study the biological and genetic properties of an actual epidemic human rotavirus A (RVA) strain Wa G1P[8] genotype. METHODS: RVA Wa reproduction in a monolayer continuous cell lines, purification and concentration of RVA antigen, PAAG electrophoresis and Western-Blot, electrophoresis of viral genomic RNA segments, sequencing. RESULTS: Human RVA G1P[8] Wa strain biological and molecular genetic properties were assessed in the process of the adaptation to MARC145 continuous cell line. Cell cultured RVA antigen was purified, concentrated and then characterized by the method of PAAG electrophoresis and immunoblot. To verify RVA Wa genome identity, electrophoresis of viral genomic RNA segments was performed. The lack of accumulation of changes in the RVA Wa genome during adaptation to various cell cultures and during serial passages was demonstrated by sequencing fragments of the viral genome. CONCLUSIONS: RVA Wa strain is stable, it possesses high biological activity: it has been successfully adapted to the MARC145 cell line and RVA Wa virus titer after the adaptation reached 7,5-7,7 lg TCID50/ml. The identity of the cultivated RVA to the original strain Wa G1P[8] was confirmed.
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Antígenos Virales , Genoma Viral , Filogenia , ARN Viral , Infecciones por Rotavirus , Rotavirus , Animales , Antígenos Virales/biosíntesis , Antígenos Virales/genética , Línea Celular , Chlorocebus aethiops , Genotipo , Humanos , ARN Viral/biosíntesis , ARN Viral/genética , Rotavirus/genética , Rotavirus/crecimiento & desarrollo , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/genética , Infecciones por Rotavirus/metabolismo , PorcinosRESUMEN
INTRODUCTION: Rotovirus infection (RVI) caused by the dsRNA-containing virus from genus Rotavirus, Reoviridae family, belonging to group A (RVA), is the cause of severe diarrhea in human and other mammalian species. Vaccination is the most effective way to reduce the incidence of RVI. At present, the effectiveness of using gnotobiotic piglets as a universal model for reproducing human rotavirus infection and assessing the quality of RVI vaccine preparations has been experimentally proven. OBJECTIVES: Evaluation of immunogenic activity of the cloned RVA Wa strain in the new-born Vietnamese potbellied piglets trial. MATERIAL AND METHODS: Development of viral preparations of the cloned human Wa strain PBA, development of human RVA rVP6, ELISA, polymerase chain reaction with reverse transcription, immunization and experimental infection of newborn piglets. RESULTS: The article presents the results of the experiment on double immunization of newborn piglets with native virus preparations with the infection activity 5.5 lg TCID50/ml, 3 cm3 per dose, HRV with adjuvant 500 µg per dose and mock preparation (control group) followed with experimental inoculation of all animals with virulent virus strain Wa G1P[8] human RVA with infectious activity of 5.5 lg TCID50/ml in 5 cm3 dose. Development of clinical signs of disease and animal death were observed only in control group. RT-PCR system to detect RVA RNA in rectal swabs, samples of small intestine and peripheral lymph nodes was developed. ELISA based on obtained human RVA rVP6 was developed and results on RVA-specific IgG-antibodies in serum samples of experimental piglets are presented. CONCLUSION: In the course of the research, a high immunogenic activity of the native and purified virus of the cloned Wa RVA strain Wa was established and the possibility of its use as the main component of the RVI vaccine was confirmed. The possibility of using conventional newborn pigs instead of gnotobiotic piglets as an experimental model was demonstrated.
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Antígenos Virales/genética , Proteínas de la Cápside/genética , Infecciones por Reoviridae/genética , Reoviridae/genética , Rotavirus/genética , Animales , Animales Recién Nacidos/inmunología , Animales Recién Nacidos/virología , Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Reoviridae/inmunología , Infecciones por Reoviridae/inmunología , Infecciones por Reoviridae/prevención & control , Infecciones por Reoviridae/virología , Rotavirus/inmunología , Porcinos , Vacunas Virales/inmunologíaRESUMEN
A quantum particle transport induced in a spatially periodic potential by a propagating plane wave has a number of important implications in a range of topical physical systems. Examples include acoustically driven semiconductor superlattices and cold atoms in an optical crystal. Here we apply a kinetic description of the directed transport in a superlattice beyond standard linear approximation, and utilize exact path-integral solutions of the semiclassical transport equation. We show that the particle drift and average velocities have nonmonotonic dependence on the wave amplitude with several prominent extrema. Such nontrivial kinetic behavior is related to global bifurcations developing with an increase of the wave amplitude. They cause dramatic transformations of the system phase space and lead to changes of the transport regime. We describe different types of phase trajectories contributing to the directed transport and analyze their spectral content.
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The modern clinical practice is characterized by intensive introduction of innovative technologies for improving treatment and diagnostic procedures, minimizing their impact on the patient, complications rate and economic reasons. One of the priorities in this area is both diagnostic and therapeutic endoscopy. The degree of practical use of innovative endoscopic technologies depends on not only the quality of care, but also their economic reasons. Endoscopic treatment has become the method of choice for gastrointestional bleeding, extraction of foreign bodies, obstructive jaundice, polyps of the gastrointestinal tract, achalasia, esophageal strictures, etc. So, the current state of scientific and technical advances have made minimally invasive surgical intervention one of the main direction of development of surgery. The further improvement will be considered integration of minimally invasive and information technologies. The widespread introduction of minimally invasive surgical techniques in clinical practice indicates their undoubted efficiency and availability, especially in the multidisciplinary hospitals that provide various types of specialized high-technological medical care. This allows to embody the principle of multidisciplinary and personalized approach in the treatment of patients. The main result of such practices is to reduce the duration of inpatient treatment, a significant reduction in the degree of invasive impact and risk of surgical interventions, diagnostic interventions and operations in a 'one-day hospital', with a total increase of efficiency of surgical treatment, and with high quality of life of patients.
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Endoscopía , Procedimientos Quirúrgicos Mínimamente Invasivos , Constricción Patológica/cirugía , Acalasia del Esófago/cirugía , Cuerpos Extraños/cirugía , Hospitales , Humanos , Calidad de VidaRESUMEN
Rotavirus was first isolated in 1973 in Australia from children with diarrhea. Hundreds of thousands of children die annually in developing countries from this virus with the mortality peaks in the most impoverished among them. According to wHo, rotavirus infection claims about 440 thousands children lives each year, being third in the mortality rate after pneumonia and malaria. Rotavirus is widely spread throughout the world and by the age of five years almost every child encountered this pathogen at least once. Rotavirus has a high genetic and antigenic diversity. The most important for humans is the group A rotavirus, and the most common by far genotypes are G1P [8], G2P [4], G3P [8], G4P [8], G9P [8], and to a lesser extent G12P [8]. There are three gene constellations described in rotavirus designated Wa, Ds-1, and Au-1. It is believed that they originated from rotaviruses of pigs, cattle, dogs, and cats, respectively. Cases of rotavirus interspecies transmission from animal to humans were reported. The first vaccines against rotavirus infection were based on naturally attenuated virus of the animal origin. Their efficiency, especially in developing countries, was inadequate, but today China and India use vaccines based on animal rotaviruses. Using the method of gene reassortation with the cattle rotavirus WC3 as a backbone, pentavalent vaccine against most common human rotavirus serotypes was developed and now successfully used as RotaTeq. The ability of rotavirus to protect against heterologous isolates was taken into account in the development of other vaccine, Rotarix, created on the basis of rotavirus genotype G1P1A [8]. The efficacy of these vaccines in developing countries is significantly reduced (51%), the cost of a dose is high, and so the search for more effective, safe, and inexpensive vaccines against rotavirus continues around the world.
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The main pharmacokinetic parameters (AUC0-∞, Tmax, Cmax, Cl/F, t1/2 el, MRT, Cmax/AUC0-I, Vd/F) of afobazole base in a new pharmaceutical composition and afobazole dihydrochloride substance after single peroral administration have been determined in rats. The availability of afobazole base pharmaceutical composition relative to that of the substance amounted to 153.2%.
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Bencimidazoles/farmacología , Bencimidazoles/farmacocinética , Morfolinas/farmacología , Morfolinas/farmacocinética , Administración Oral , Animales , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Masculino , RatasRESUMEN
THE AIM: to analyze the effectiveness and possible complications of endoscopic biliary drainage (BD) using self-expanding metal stent (SEMS) in patients with malignant jaundice (MJ). METHODS: From January 2010 to January 2014 in endoscopy department of Pirogov National medical and surgical Center were operated 64 patients with MJ, 38 of them with SEMS. The average patient's age was 65.4 ± 14.5 years. The mean duration of jaundice was 13 ± 5.4 days before drainage. The remaining 6 patients (15.8%) were operated with preliminary PTBD. In all 38 patients were diagnosed unresectable tumors. RESULTS: successful endoscopic BD were achieved in all 38 patients. 35 patients were drained with transpapillary SEMS and 3 patients with EUS-guided choledochoduodenoanastomoses (EUS-CDA). Early postoperative complications were observed in 3 (7.8%) patients with no lethality. CONCLUSION: endoscopic BD with SEMS is an effective method of internal drainage for inoperable pancreatobiliary tumors, providing adequate BD for the entire duration of life expectancy. In case of failed transpapillary drainage EUS-guided biliodigestive anastomoses were performed. The complication rate of endoscopic BD in patients with malignant pancreatobiliary tumors in our study was 7.8% and comparable with complication level due to ERCP/EST for benign pathology.
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Aleaciones , Endoscopía Gastrointestinal/métodos , Ictericia Obstructiva/cirugía , Neoplasias Hepáticas/cirugía , Stents , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Ictericia Obstructiva/diagnóstico por imagen , Ictericia Obstructiva/etiología , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiografía , Estudios RetrospectivosRESUMEN
We investigate the effects of a linear resonator on the high-frequency dynamics of electrons in devices exhibiting negative differential conductance. We show that the resonator strongly affects both the dc and ac transport characteristics of the device, inducing quasiperiodic and high-frequency chaotic current oscillations. The theoretical findings are confirmed by experimental measurements of a GaAs/AlAs miniband semiconductor superlattice coupled to a linear microstrip resonator. Our results are applicable to other active solid state devices and provide a generic approach for developing modern chaos-based high-frequency technologies including broadband chaotic wireless communication and superfast random-number generation.
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The article describes the clinical case and analyzes the literature concerning endoprosthesis replacement in the case of traumatic thoracic aortic injury in polytrauma. Current strategy of diagnostics and treatment of patient in critical condition with rupture of isthmic aortic part is based on the principle of multistage surgical treatment (damage control orthopedic). The external fixation of multiple pelvis and extremities fractures and on-time implantation of stent-graft in thoracic aortic part were performed at first hours after the admission. A condition of the patient was stabilized. The delayed reconstructive operations on pelvis and extremities bones allowed obtaining the satisfactory functional result. The principles of staged surgical treatment and the use of on-time high-technology methods allowed saving life for the patient even in critical situation in I level traumatologic centre.
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Aorta Torácica , Traumatismo Múltiple , Complicaciones Posoperatorias/terapia , Sepsis , Injerto Vascular , Heridas no Penetrantes , Adulto , Aorta Torácica/lesiones , Aorta Torácica/fisiopatología , Aorta Torácica/cirugía , Prótesis Vascular , Humanos , Masculino , Traumatismo Múltiple/complicaciones , Traumatismo Múltiple/fisiopatología , Reoperación , Rotura/diagnóstico , Rotura/etiología , Rotura/fisiopatología , Rotura/cirugía , Sepsis/etiología , Sepsis/terapia , Stents , Tomografía Computarizada por Rayos X , Índices de Gravedad del Trauma , Resultado del Tratamiento , Injerto Vascular/efectos adversos , Injerto Vascular/métodosRESUMEN
Pharmacokinetic parameters of himantane and its metabolites in the blood plasma of rabbits were compared after single administration of himantane solution in a dose of 25 mg intravenously and 100 mg orally. It was established that the original substance is characterized by low absolute bioavailability (7.95%). Himantane is subjected to first-pass effect and is extensively metabolized in the liver to metabolites with m/z 266 and 250.
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Adamantano/análogos & derivados , Adamantano/administración & dosificación , Adamantano/sangre , Adamantano/metabolismo , Adamantano/farmacocinética , Administración Oral , Animales , Disponibilidad Biológica , Estudios Cruzados , Inyecciones Intravenosas , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , ConejosRESUMEN
We study theoretically the dynamical rectification of a terahertz AC electric field, i.e. the DC current and voltage response to the incident radiation, in strongly coupled semiconductor superlattices. We address the problem of stability against electric field domains: a spontaneous DC voltage is known to appear exactly for parameters for which a spatially homogeneous electron distribution is unstable. We show that by applying a weak direct current bias the rectifier can be switched from a state with zero DC voltage to one with a finite voltage in full absence of domains. The switching occurs near the conditions of dynamical symmetry breaking of an unbiased semiconductor superlattice. Therefore our scheme allows for the generation of DC voltages that would otherwise be unreachable due to domain instabilities. Furthermore, for realistic, highly doped wide miniband superlattices at room temperature, the generated DC field can be nearly quantized, that is, be approximately proportional to an integer multiple of hω/ea where a is the superlattice period and ω is the AC field frequency.
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Simulación por Computador , Conductividad Eléctrica , Semiconductores , Radiación Terahertz , ElectronesRESUMEN
The pharmacokinetics ofhemantane after administration in different ways has been studied in rats. It is established that hemantane introduced both orally (p.o.) and intravenously (i.v.) is very intensively metabolized, with the main metabolites characterized by m/z = 250 and 266 and detected for 6 hours after the administration in both ways. Hemantane shows high rate of permeability into its target organ--brain--whereas the permeation of its metabolites is extremely low. The absolute bioavailability ofhemantane upon p.o. administration was 14.1%. The substance is subject to the "first-pass effect". The unchanged substance was determined in daily urine and feces in very small fractions of the administered dose: 0.23% in urine and 0.08% in feces after i.v. administration and 0.02% in feces after p.o. administration. Thus, it may be concluded that the substance is completely absorbed in rats from the gastro-intestinal tract into systemic blood circulation.