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1.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065184

RESUMEN

An x-ray imaging scheme using spherically bent crystals was implemented on the Z-machine to image x rays emitted by the hot, dense plasma generated by a Magnetized Liner Inertial Fusion (MagLIF) target. This diagnostic relies on a spherically bent crystal to capture x-ray emission over a narrow spectral range (<15 eV), which is established by a limiting aperture placed on the Rowland circle. The spherical crystal optic provides the necessary high-throughput and large field-of-view required to produce a bright image over the entire, one-cm length of the emitting column of a plasma. The average spatial resolution was measured and determined to be 18 µm for the highest resolution configuration. With this resolution, the radial size of the stagnation column can be accurately determined and radial structures, such as bifurcations in the column, are clearly resolved. The success of the spherical-crystal imager has motivated the implementation of a new, two-crystal configuration for identifying sources of spectral line emission using a differential imaging technique.

2.
Rev Sci Instrum ; 94(5)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37184347

RESUMEN

We report on progress implementing and testing cryogenically cooled platforms for Magnetized Liner Inertial Fusion (MagLIF) experiments. Two cryogenically cooled experimental platforms were developed: an integrated platform fielded on the Z pulsed power generator that combines magnetization, laser preheat, and pulsed-power-driven fuel compression and a laser-only platform in a separate chamber that enables measurements of the laser preheat energy using shadowgraphy measurements. The laser-only experiments suggest that ∼89% ± 10% of the incident energy is coupled to the fuel in cooled targets across the energy range tested, significantly higher than previous warm experiments that achieved at most 67% coupling and in line with simulation predictions. The laser preheat configuration was applied to a cryogenically cooled integrated experiment that used a novel cryostat configuration that cooled the MagLIF liner from both ends. The integrated experiment, z3576, coupled 2.32 ± 0.25 kJ preheat energy to the fuel, the highest to-date, demonstrated excellent temperature control and nominal current delivery, and produced one of the highest pressure stagnations as determined by a Bayesian analysis of the data.

3.
Phys Rev Lett ; 125(15): 155002, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-33095639

RESUMEN

We present experimental results from the first systematic study of performance scaling with drive parameters for a magnetoinertial fusion concept. In magnetized liner inertial fusion experiments, the burn-averaged ion temperature doubles to 3.1 keV and the primary deuterium-deuterium neutron yield increases by more than an order of magnitude to 1.1×10^{13} (2 kJ deuterium-tritium equivalent) through a simultaneous increase in the applied magnetic field (from 10.4 to 15.9 T), laser preheat energy (from 0.46 to 1.2 kJ), and current coupling (from 16 to 20 MA). Individual parametric scans of the initial magnetic field and laser preheat energy show the expected trends, demonstrating the importance of magnetic insulation and the impact of the Nernst effect for this concept. A drive-current scan shows that present experiments operate close to the point where implosion stability is a limiting factor in performance, demonstrating the need to raise fuel pressure as drive current is increased. Simulations that capture these experimental trends indicate that another order of magnitude increase in yield on the Z facility is possible with additional increases of input parameters.

4.
Rev Sci Instrum ; 91(6): 063507, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32611066

RESUMEN

Magnetized Liner Inertial Fusion (MagLIF) at Sandia National Laboratories involves a laser preheating stage where a few-ns laser pulse passes through a few-micron-thick plastic window to preheat gaseous fusion fuel contained within the MagLIF target. Interactions with this window reduce heating efficiency and mix window and target materials into the fuel. A recently proposed idea called "Laser Gate" involves removing the window well before the preheating laser is applied. In this article, we present experimental proof-of-principle results for a pulsed-power implementation of Laser Gate, where a thin current-carrying wire weakens the perimeter of the window, allowing the fuel pressure to push the window open and away from the preheating laser path. For this effort, transparent targets were fabricated and a test facility capable of studying this version of Laser Gate was developed. A 12-frame bright-field laser schlieren/shadowgraphy imaging system captured the window opening dynamics on microsecond timescales. The images reveal that the window remains largely intact as it opens and detaches from the target. A column of escaping pressurized gas appears to prevent the detached window from inadvertently moving into the preheating laser path.

5.
Actas Urol Esp (Engl Ed) ; 43(4): 176-181, 2019 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30824338

RESUMEN

OBJECTIVE: To analyse the evolution and adequacy of referrals from Primary Care to Urology, after the implementation of referral protocols on the most frequent urological diseases and the establishment of a continuing education program. MATERIAL AND METHODS: A Primary Care-Urology work group was created in 2011. Initially, performance and clinical practice protocols in prostatic pathology (BPH and PSA) were established. These were supported by training sessions for primary care physicians. After analysing the effect of the mentioned joint work, 3more (scrotal pathology, urinary tract infections and urinary incontinence) were included. We analysed and compared the referrals and their adequacy before and after the establishment of the protocols. RESULTS: The most common referral causes were symptoms of the lower urinary tract due to BPH, which initially represented 22.8% of the total, and decreased to 16.9%. After the introduction of the new algorithms, we observed a decrease in referrals for scrotal pathology (13-14% to 7.8%), an increase in urinary incontinence referrals (3% al 10.3%) and those related to urinary tract infections remained stable. The adequacy to the protocols improved progressively: LUTS from 46% to 65.3%; PSA from 55% to 84.4% and urinary incontinence from 66.2% to 73.1%. Adequacy in scrotal pathology decreased (de 67.1% a 63.3%), while in UTI it stayed much the same (around 76%). CONCLUSIONS: The joint work between Urology and Primary Care achieves an improvement in referrals adequacy regarding the most frequent urological pathologies.


Asunto(s)
Educación Médica Continua/organización & administración , Atención Primaria de Salud/estadística & datos numéricos , Desarrollo de Programa , Derivación y Consulta/estadística & datos numéricos , Urología/estadística & datos numéricos , Algoritmos , Continuidad de la Atención al Paciente/organización & administración , Correo Electrónico/organización & administración , Correo Electrónico/estadística & datos numéricos , Correo Electrónico/tendencias , Femenino , Medicina General/organización & administración , Medicina General/estadística & datos numéricos , Humanos , Síntomas del Sistema Urinario Inferior/diagnóstico , Síntomas del Sistema Urinario Inferior/epidemiología , Síntomas del Sistema Urinario Inferior/terapia , Masculino , Derivación y Consulta/normas , Derivación y Consulta/tendencias , Estudios Retrospectivos , España , Incontinencia Urinaria/diagnóstico , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/terapia , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/epidemiología , Infecciones Urinarias/terapia
6.
Phys Rev Lett ; 116(6): 065001, 2016 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-26918996

RESUMEN

Enhanced implosion stability has been experimentally demonstrated for magnetically accelerated liners that are coated with 70 µm of dielectric. The dielectric tamps liner-mass redistribution from electrothermal instabilities and also buffers coupling of the drive magnetic field to the magneto-Rayleigh-Taylor instability. A dielectric-coated and axially premagnetized beryllium liner was radiographed at a convergence ratio [CR=Rin,0/Rin(z,t)] of 20, which is the highest CR ever directly observed for a strengthless magnetically driven liner. The inner-wall radius Rin(z,t) displayed unprecedented uniformity, varying from 95 to 130 µm over the 4.0 mm axial height captured by the radiograph.

7.
Int J Immunogenet ; 42(3): 182-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25876437

RESUMEN

Elevated IgE levels in the atopic triad of asthma, allergic rhinitis and atopic dermatitis is a multifactorial condition whose genetic component involves interaction of several gene loci. One hundred and two matched pairs of allergic and nonallergic individuals were phenotyped for total serum IgE level using enzyme-linked immunosorbent assay (ELISA). Atopic status was defined by serum IgE concentration ≥100 IU mL(-1) . SNPs genotyped include the IL4 -590C>T (rs2243250), FCER1B E237G (rs569108), CD14 -159C>T (rs2569190), IL4RA Q551R (rs1801275) and ADRB2 R16G (rs1042713). Gene-gene interaction was analysed using multifactor-dimensionality reduction (MDR). Significant association between atopic allergy and the IL4 -590C>T polymorphism was confirmed in three genetic models. Interaction among the 5 gene variants was validated by MDR. The five-locus model was chosen as the best to describe the interaction of the SNPs within the context of atopy. The strongest interaction was between IL4 -590C>T and IL4RA Q551R and between FCER1B E237G and ADRB2 R16G. The IL4 variant also interacts synergistically with the FCER1B and ADRB2 coding variants. CD14 -159C>T, in general, interacts antagonistically with the rest of the SNPs. In conclusion, a five-locus interaction exists among IL4 -590C>T, FCER1B E237G, CD14 -159C>T, IL4RA Q551R and ADRB2 R16G in Filipino cases of atopic allergy.


Asunto(s)
Epistasis Genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Variación Genética , Hipersensibilidad/genética , Alelos , Estudios de Casos y Controles , Frecuencia de los Genes , Genotipo , Humanos , Hipersensibilidad/diagnóstico , Hipersensibilidad/inmunología , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/genética , Hipersensibilidad Inmediata/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Modelos Genéticos , Oportunidad Relativa , Fenotipo , Reproducibilidad de los Resultados
8.
Phys Rev Lett ; 113(15): 155003, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25375714

RESUMEN

This Letter presents results from the first fully integrated experiments testing the magnetized liner inertial fusion concept [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)], in which a cylinder of deuterium gas with a preimposed 10 Taxial magnetic field is heated by Z beamlet, a 2.5 kJ, 1 TW laser, and magnetically imploded by a 19 MA, 100 ns rise time current on the Z facility. Despite a predicted peak implosion velocity of only 70 km = s, the fuel reaches a stagnation temperature of approximately 3 keV, with T(e) ≈ T(i), and produces up to 2 x 10(12) thermonuclear deuterium-deuterium neutrons. X-ray emission indicates a hot fuel region with full width at half maximum ranging from 60 to 120 µm over a 6 mm height and lasting approximately 2 ns. Greater than 10(10) secondary deuterium-tritium neutrons were observed, indicating significant fuel magnetization given that the estimated radial areal density of the plasma is only 2 mg = cm(2).

9.
Phys Rev Lett ; 113(15): 155004, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25375715

RESUMEN

Magnetizing the fuel in inertial confinement fusion relaxes ignition requirements by reducing thermal conductivity and changing the physics of burn product confinement. Diagnosing the level of fuel magnetization during burn is critical to understanding target performance in magneto-inertial fusion (MIF) implosions. In pure deuterium fusion plasma, 1.01 MeV tritons are emitted during deuterium-deuterium fusion and can undergo secondary deuterium-tritium reactions before exiting the fuel. Increasing the fuel magnetization elongates the path lengths through the fuel of some of the tritons, enhancing their probability of reaction. Based on this feature, a method to diagnose fuel magnetization using the ratio of overall deuterium-tritium to deuterium-deuterium neutron yields is developed. Analysis of anisotropies in the secondary neutron energy spectra further constrain the measurement. Secondary reactions also are shown to provide an upper bound for the volumetric fuel-pusher mix in MIF. The analysis is applied to recent MIF experiments [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z Pulsed Power Facility, indicating that significant magnetic confinement of charged burn products was achieved and suggesting a relatively low-mix environment. Both of these are essential features of future ignition-scale MIF designs.

10.
Rev Sci Instrum ; 85(11): 11E609, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430355

RESUMEN

Sandia's Z Machine uses its high current to magnetically implode targets relevant to inertial confinement fusion. Since target performance is highly dependent on the applied drive field, measuring magnetic field at the target is essential for accurate simulations. Recently, the magnetic field at the target was measured through splitting of the sodium 3s-3p doublet at 5890 and 5896 Å. Spectroscopic dopants were applied to the exterior of the target, and spectral lines were observed in absorption. Magnetic fields in excess of 200 T were measured, corresponding to drive currents of approximately 5 MA early in the pulse.

11.
Phys Rev Lett ; 111(23): 235005, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24476283

RESUMEN

Novel experimental data are reported that reveal helical instability formation on imploding z-pinch liners that are premagnetized with an axial field. Such instabilities differ dramatically from the mostly azimuthally symmetric instabilities that form on unmagnetized liners. The helical structure persists at nearly constant pitch as the liner implodes. This is surprising since, at the liner surface, the azimuthal drive field presumably dwarfs the axial field for all but the earliest stages of the experiment. These fundamentally 3D results provide a unique and challenging test for 3D-magnetohydrodynamics simulations.

12.
Rev Sci Instrum ; 83(10): 10D714, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23126888

RESUMEN

The pinned optically aligned diagnostic dock (PODD) is a multi-configuration diagnostic platform designed to measure x-ray emission on the Z facility. The PODD houses two plasma emission acquisition (PEA) systems, which are aligned with a set of precision machined pins. The PEA systems are modular, allowing a single diagnostic housing to support several different diagnostics. The PEA configurations fielded to date include both time-resolved and time-integrated, 1D spatially resolving, elliptical crystal spectrometers, and time-integrated, 1D spatially resolving, convex crystal spectrometers. Additional proposed configurations include time-resolved, monochromatic mirrored pinhole imagers and arrays of filtered x-ray diodes, diamond photo-conducting diode detectors, and bolometers. The versatility of the PODD system will allow the diagnostic configuration of the Z facility to be changed without significantly adding to the turn-around time of the machine. Additionally, the PODD has been designed to allow instrument setup to be completed entirely off-line, leaving only a refined alignment process to be performed just prior to a shot, which is a significant improvement over the instrument the PODD replaces. Example data collected with the PODD are presented.

13.
Rev Sci Instrum ; 79(9): 093512, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19044418

RESUMEN

Soft metal gaskets (indium and silver) were used to reduce contact resistance between the wire and the electrode in an aluminum wire Z pinch by more than an order of magnitude over the best weighted contact case. Clamping a gasket over a Z-pinch wire compresses the wire to the electrode with a greater normal force than possible with wire weights. Average contact resistance was reduced from the range of 100-3000 Omega (depending on wire weight mass) to 1-10 Omega with soft metal gaskets. Single wire experiments (13 microm Al 5056) on a 16 kA, 100 kV Marx bank showed an increase in light emission (97%) and emission volume (100%) of the plasma for the reduced contact resistance cases. The measured increases in plasma volume and light emission indicate greater energy deposition in the ablated wire. Additionally, dual-wire experiments showed plasma edge effects were significantly decreased in the soft metal gasket contact case. The average height of the edge effects was reduced by 51% and the width of the edge effects was increased by 40%, thus the gasket contact case provided greater axial uniformity in the plasma expansion profile of an individual wire.

14.
Pharmazie ; 62(11): 847-52, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18065101

RESUMEN

The apparent electrophoretic mobilities of indomethacin in beta-cyclodextrin at a range of concentrations were measured directly by capillary electrophoresis. Three different linear plots and a non linear plot are proposed for the apparent binding constant calculations, based on the fact that the molar ratio of the inclusion complex was 1:1. K values obtained at 298 K were 421 M(-1) (double reciprocal fit), 488 M(-1) (x-reciprocal fit), 428 M(-1) (y-reciprocal fit) and 490 M(-1) (non linear fit). The corresponding K values at 313 K were 380 M(-1) (double reciprocal fit), 355 M(-1) (x-reciprocal fit), 366 M(-1) (y-reciprocal fit) and 339 M(-1) (non linear fit). Using the proposed methods, the binding constant of the indomethacin-beta-cyclodextrin inclusion complex can be obtained easily. The methods have been applied to obtain the values of the constant K under different experimental conditions. Under optimized conditions the K constant is temperature dependent and non-arrhenian behaviour was observed.


Asunto(s)
Indometacina/química , beta-Ciclodextrinas/química , Tampones (Química) , Química Farmacéutica , Dimetilsulfóxido , Electroforesis Capilar , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Dinámicas no Lineales , Solventes , Espectrometría de Fluorescencia , Temperatura , Termodinámica
15.
Pharmazie ; 62(4): 262-5, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17484280

RESUMEN

A high-performance capillary electrophoretic (CE) method has been developed for obtaining electropherograms of various extracts and the commercial formulation (fingerprints) of Hedera helix L used in Argentina as a cough's treatment. Also, a capillary zone electrophoresis (CZE) method was developed for the search, identification and determination of some possible adulterants. These likely adulterants are common synthetic drugs used in respiratory diseases (antitussive, decongestant and bronchodilator agents). Under optimum conditions, the analytes (ephedrine, codeine, diphenhydramine and constituents of H. helix formulations) were separated within less than 10 min in 20 mM sodium tetraborate buffer (pH 9.0). The present procedure was validated with respect to selectivity, linearity range, limits of detection (LOD) and quantification (LOQ), precision (repeatability and intermediate precision), solution stability and accuracy; the results obtained were satisfactory. Good linearity was obtained over two orders of magnitude and detection limits (S/N = 3) were better than 1.2 microg ml(-1) for all analytes. The CE methodology was successfully applied to the search and subsequent determination of ephedrine, codeine and diphenhydramine in H. helix extracts and its phytopharmaceutical products.


Asunto(s)
Hedera/química , Tampones (Química) , Química Farmacéutica , Codeína/análisis , Difenhidramina/análisis , Contaminación de Medicamentos , Electroforesis Capilar , Efedrina/análisis , Concentración de Iones de Hidrógeno , Extractos Vegetales/química , Reproducibilidad de los Resultados
16.
Pharmazie ; 61(12): 981-4, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17283652

RESUMEN

This study describes the development and validation of a method for quantification of the antiulcer experimental drug xanthatin in tablets by capillary electrophoresis (CE). Solid oral dosage forms based on xanthatin were designed and assayed on rats. A CE methodology was developed; the parameters evaluated were: background electrolyte composition, concentration and pH, applied voltage and sample preparation. The method was validated in terms of range of linearity, limits of detection (LOD) and quantification (LOQ), accuracy, precision and selectivity and then applied to the pharmaceutical dosage forms. Xanthatin determination was carried out in less than 3 min with a 20 mM sodium tetraborate buffer, pH 9.20. Drug concentration per tablet found was 2.97 +/- 0.2 mg. Calibration plots were linear over at least three orders of magnitude of analyte concentrations, LOD and LOQ were 7.6 and 26 microg mL(-1) respectively. For accuracy evaluation a recovery test was performed, the values being better than 98.6%. With respect to precision, the results obtained were better than 1.02 RSD% (repeatability) and 1.54% (intermediate precision). After the manufacturing process the resulting tablets were biologically active. The methodology developed is useful, simple and rapid for xanthatin determination in tablets.


Asunto(s)
Antiulcerosos , Furanos/análisis , Xanthium/química , Fenómenos Químicos , Química Física , Electroforesis Capilar , Etanol , Furanos/aislamiento & purificación , Furanos/farmacología , Indicadores y Reactivos , Control de Calidad , Reproducibilidad de los Resultados , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/prevención & control , Comprimidos
18.
Farm Hosp ; 28(6 Suppl 1): 19-26, 2004.
Artículo en Español | MEDLINE | ID: mdl-15649112

RESUMEN

OBJECTIVE: To establish the impact of a pharmaceutical care program on the improvement of adherence to antiretroviral therapy, and on patient immunologic and virologic outcome. MATERIALS AND METHODS: A multicenter, observational, prospective study in a HIV-infected patient cohort under treatment with antiretrovirals selected by random sampling in 19 Spanish hospitals. The study lasted 12 months, in which the program was applied through a baseline preprocedural visit and 4 quarterly visits. Adherence estimation was based on pill counting. An adherence > or = 90, or > or = 95% was considered adequate (in two time points). RESULTS: 541 patients were included, most of them were males (68.8%) between 20 and 78 years of age. Major risk groups included injecting drug users (43.4%) and heterosexuals (29.4%). Sixty percent had already received treatment for more than 3 years. Mean baseline viral load and CD4 count values were 32,866 copies/ml and 485 cells/mm3, respectively. Throughout the study a slight increase in the percentage of adherent patients was seen; however, statistical significance was not reached (64.3 and 79.2% of patients showed an adherence > 95 and > 90%, respectively, during the fourth quarter, versus 59.8 and 75.5% at baseline). A statistically significant decrease in viral load and increase in CD4 cells was seen following program application. The percentage of patients with a viral load < 200 copies/ml was 72.2, 76.7, and 75.0% at the 2nd, 3rd, and 4th quarters, respectively, versus 64.2% at baseline. CD4 cell counts increased by 50 cells/mm3 on average from the start to the end of follow-up. CONCLUSIONS: Patients included in the program had a good immunologic and virologic outcome, and a trend towards an increased percentage of patients with good adherence was also seen. These results confirm the need to implement follow-up programs for patients receiving antiretrovirals in order to ensure maximum therapeutic benefits.


Asunto(s)
Antirretrovirales/uso terapéutico , Cooperación del Paciente/estadística & datos numéricos , Servicio de Farmacia en Hospital , Evaluación de Programas y Proyectos de Salud , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
19.
Rev Neurol ; 33(4): 328-33, 2001.
Artículo en Español | MEDLINE | ID: mdl-11588725

RESUMEN

INTRODUCTION: Jejunal and ileal diverticula are acquired lesions that are often associated with intestinal motility disturbances like those occurring in myopathies and neuropathies with visceral affection. Mitochondrial neurogastrointestinal encephalomyopathy is characterized by gastrointestinal dysmotility, cachexia, ptosis with external ophthalmoparesis, neuropathy, leukoencephalopathy and laboratory evidence of mitochondrial alteration. CLINICAL CASE: A female patient that since 9 months age presented digestive symptoms: diarrhea, nauseous, vomits, slow digestions and abdominal pain. She had myopia. At the age of 20, in a seven months period, she precised urgent abdominal surgical intervention in three occasions for acute diffuse peritonitis related to jejunal and ileal diverticula. She presented cachexia, mild palpebral ptosis, external ophthalmoparesis, hypertrophic major auricular nerves, scoliosis, pes cavus, distal weakness and hypoesthesia in extremities, bilateral neurosensorial hypoacusia and lactic acidosis. The electroneurographic study was compatible with severe chronic demyelinating sensitive motor polyneuropathy. In the cerebral MR leukoencephalopathy was detected. In muscular tissue it was seen alteration in all fibers type I with numerous lipid vacuoles and an increase of mitochondrial number in the form of thick grains and subsarcolemmal mitochondrial bags. There was no ragged red fibers nor ultrastructural mitochondrial alterations. There was chain respiratory complex III deficiency. CONCLUSIONS: In patients with intestinal dysmotility manifestations and jejunal and ileal diverticula neuropathies and myopathies with visceral affection must be suspected, among them MNGIE syndrome.


Asunto(s)
Encéfalo/patología , Demencia Vascular/diagnóstico , Diverticulitis del Colon/complicaciones , Motilidad Gastrointestinal/fisiología , Encefalomiopatías Mitocondriales/complicaciones , Encefalomiopatías Mitocondriales/fisiopatología , Peritonitis/etiología , Enfermedad Aguda , Adulto , Demencia Vascular/complicaciones , Diverticulitis del Colon/cirugía , Femenino , Humanos , Íleon/cirugía , Yeyuno/cirugía , Imagen por Resonancia Magnética , Peritonitis/diagnóstico , Peritonitis/cirugía
20.
J Chromatogr B Biomed Sci Appl ; 751(2): 371-6, 2001 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-11236094

RESUMEN

Nevirapine is an antiretroviral agent belonging to the class of non-nucleoside reverse transcriptase inhibitors. We describe a fast, simple isocratic reversed-phase high-performance liquid chromatography method with a 30-mm long column for assaying nevirapine in human serum. After deproteinization of 200 microl serum samples with 50% trichloroacetic acid, the supernatant was injected into a reversed-phase C18 column, using 10 mM phosphate buffer (pH 5)-acetonitrile (82:18, v/v) as the mobile phase. Peak detection was performed at 240 nm. Nevirapine retention time was 2 min. The method was validated over 0.1-10 microg/ml and the assay was linear over this concentration range (r2>0.998). Within- and between-day precisions were less than 5.4%. The lower limit of quantification was 0.1 microg/ml. Nevirapine in human serum samples was stable for 2 days at 20-25 degrees C, 15 days at 4 degrees C and 3 months at -20 degrees C.


Asunto(s)
Fármacos Anti-VIH/sangre , Cromatografía Líquida de Alta Presión/métodos , Nevirapina/sangre , Inhibidores de la Transcriptasa Inversa/sangre , Calibración , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta
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