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1.
J Plast Reconstr Aesthet Surg ; 74(2): 364-369, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32888861

RESUMEN

INTRODUCTION: With the emergence of blunt-tipped microcannulas, there is a hypothesis that these could cause less damage and reduce pain as compared to conventional sharp needles in eyelid surgery. The purpose is to determine whether an 18G blunt-tipped cannula can be better than a 26G needle. METHODS: This prospective, observer-blinded, randomized clinical trial was conducted from June 2017 to December 2018. Sixty-eight patients were randomized to receive local anesthesia injections for upper blepharoplasty. Infiltration was performed by using a 26-gauge sharp needle on one side and on the other side, infiltration was performed by using an 18-gauge stainless-steel blunt-tipped microcannula. A numeric rating scale (NRS) from 0 to 10 was used to blindly assess pain in patients receiving anesthesia injections with both needle types. Photographs of the eyelids of each patient were taken in five different periods and used by three blinded observers to identify bruise or ecchymoses. RESULTS: A total of 136 eyelid operations were performed. There was no statistically significant difference when both groups were compared; however, the average score of pain was higher in patients taking the infiltration through the needle (2.85 versus 2.50). Regarding the evaluation of bruising and ecchymoses, the results showed that, in the five periods evaluated, there was no statistical difference in bruising and ecchymosis in the eyelids when taking the infiltration through a sharp needle when compared with that of the eyelids taking infiltration through a (blunt-tipped) microcannula. CONCLUSION: The evaluation of the blunt-tipped microcannula showed a lower pain score mean than that obtained for the sharp needle (2.5 versus 2.85) (p > 0.05). There was no statistically significant difference in the bruising and ecchymosis courses.


Asunto(s)
Anestesia Local/instrumentación , Blefaroplastia , Cánula/efectos adversos , Contusiones/prevención & control , Equimosis/prevención & control , Agujas/efectos adversos , Dolor Asociado a Procedimientos Médicos/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Anestesia Local/métodos , Contusiones/diagnóstico , Contusiones/epidemiología , Contusiones/etiología , Método Doble Ciego , Equimosis/diagnóstico , Equimosis/epidemiología , Equimosis/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Asociado a Procedimientos Médicos/diagnóstico , Dolor Asociado a Procedimientos Médicos/epidemiología , Dolor Asociado a Procedimientos Médicos/etiología , Estudios Prospectivos
3.
Science ; 345(6192): 64-8, 2014 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-24994647

RESUMEN

Supermassive black holes in the nuclei of active galaxies expel large amounts of matter through powerful winds of ionized gas. The archetypal active galaxy NGC 5548 has been studied for decades, and high-resolution x-ray and ultraviolet (UV) observations have previously shown a persistent ionized outflow. An observing campaign in 2013 with six space observatories shows the nucleus to be obscured by a long-lasting, clumpy stream of ionized gas not seen before. It blocks 90% of the soft x-ray emission and causes simultaneous deep, broad UV absorption troughs. The outflow velocities of this gas are up to five times faster than those in the persistent outflow, and, at a distance of only a few light days from the nucleus, it may likely originate from the accretion disk.

4.
Appl Radiat Isot ; 81: 179-83, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23597417

RESUMEN

Pacific Northwest National Laboratory (PNNL) is developing a capability to measure the absolute activity concentration of gaseous radionuclides using length-compensated proportional-counting. This capability will enable the validation of low-level calibration standards for use in PNNL's new shallow underground laboratory. Two sets of unequal length proportional counters have been fabricated; one set has been fabricated using ultra-low background (ULB) electroformed copper and a second set fabricated from Oxygen-Free High-Conductivity Copper (OFHC).


Asunto(s)
Gases/química , Radioisótopos/análisis , Conteo por Cintilación/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Dosis de Radiación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
J Med Primatol ; 40(3): 171-80, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21323674

RESUMEN

BACKGROUND: Cardiovascular disease is the primary cause of morbidity and mortality among captive chimpanzees. But there are no clinical definitions of normotension or hypertension in chimpanzees. METHODS: We analyzed 1 year of blood pressure (BP) data from a population of 261 healthy captive adult chimpanzees using a consistent set of criteria to ascertain health. RESULTS: Systolic BP varied by body weight. Diastolic BP varied by age. Median normotension was 126/63 mmHg, with an upper limit of 147/84 mmHg. We defined categories of pre-hypertension (148/85-153/88 mmHg) and hypertension (≥154/89 mmHg). The prevalence of elevated BP was 15%. The relative risk of mortality was 2.60, compared to normotensive animals. CONCLUSIONS: We used contemporary methods from human laboratory medicine to define reliable reference intervals for chimpanzee BP. Results allow accurate diagnosis of hypertension and pre-hypertension, and demonstrate an effect of elevated BP on mortality.


Asunto(s)
Presión Sanguínea , Hipertensión/diagnóstico , Hipertensión/epidemiología , Pan troglodytes/sangre , Factores de Edad , Animales , Peso Corporal , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Femenino , Estado de Salud , Masculino , New Mexico/epidemiología , Prehipertensión/diagnóstico , Prehipertensión/epidemiología , Prevalencia , Valores de Referencia , Factores de Riesgo
6.
Int J Artif Organs ; 32(10): 701-10, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19943231

RESUMEN

OBJECTIVES: The persistent shortage of donor organs for lung transplantation illustrates the need for new strategies in organ replacement therapy. Pulmonary tissue engineering aims at developing viable hybrid tissue for patients with chronic respiratory failure. METHODS: Dual-chamber polymer constructs that mimic the characteristics of the pulmonary air-blood interface were fabricated by microfabrication techniques using the biocompatible polymer polydimethylsiloxane. One compartment ("vascular chamber") was designed as a capillary network to mimic the pulmonary microvasculature. The other compartment ("parenchymal chamber") was designed to permit gas exchange. Immortalized mouse lung epithelium cells (MLE-12) were cultured on the surface of polystyrene microcarrier beads. These beads were subsequently injected into the parenchymal chamber of the dual-chamber microsystems. The vascular compartment was perfused with cell culture medium in a bioreactor and the construct was maintained in culture for 1 week. RESULTS: The microcarriers evenly distributed MLE-12 cells on the parenchymal compartment surface. Confluent cell layers were confirmed by fluorescent and electron microscopy. Adequate proliferation of MLE-12 cells within the construct was monitored via the DNA content. Viability of the cells was maintained over 1 week. Finally, cellular specificity and functional capacity in situ were demonstrated by immunostaining for proSP-B and proSP-C (alveolar epithelium), and by using MLE-12 cells transfected to overexpress green fluorescent protein. CONCLUSION: We conclude that functional hybrid microsystems mimicking the basic building plan of alveolar tissue can be engineered in vitro.


Asunto(s)
Órganos Bioartificiales , Barrera Alveolocapilar/fisiología , Dimetilpolisiloxanos/química , Células Epiteliales/fisiología , Alveolos Pulmonares/irrigación sanguínea , Ingeniería de Tejidos/instrumentación , Andamios del Tejido , Animales , Reactores Biológicos , Barrera Alveolocapilar/ultraestructura , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Replicación del ADN , Diseño de Equipo , Técnica del Anticuerpo Fluorescente , Proteínas Fluorescentes Verdes/genética , Péptidos y Proteínas de Señalización Intercelular , Ratones , Sistemas Microelectromecánicos , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Microvasos/fisiología , Péptidos/metabolismo , Poliestirenos/química , Precursores de Proteínas/metabolismo , Proteolípidos/metabolismo , Proteína C Asociada a Surfactante Pulmonar , Factores de Tiempo , Técnicas de Cultivo de Tejidos/instrumentación , Transfección
7.
J Cardiovasc Surg (Torino) ; 48(3): 349-57, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17505440

RESUMEN

AIM: Heart valve replacement surgeries account for 20% of all cardiac procedures. In-hospital mortality rates are approximately 6% for aortic valve replacements and 10% for mitral valve replacements. The objectives of the study are to provide nationally representative estimates of complications following aortic and mitral valve replacements and to quantify the impact of different types of complications on in-hospital outcomes. METHODS: The Nationwide Inpatient Sample was analyzed for years 2000-2003. The effect of complications on in-hospital mortality, length of stay (LOS), and hospital charges were examined using bivariate and multivariable logistic and linear regression analyses. The confounding effects of age, sex, primary diagnosis, type of valve replacement, type of admission, comorbid conditions, and hospital characteristics were adjusted. RESULTS: A total of 43,909 patients underwent aortic valve replacement as the primary procedure during the study period and 16,516 patients underwent mitral valve replacement. Complications occurred in 35.2% of those undergoing aortic valve replacements and in 36.4% of those undergoing mitral valve replacements. Almost half of these are cardiac complications and a quarter involve hemorrhage/hematoma/seroma. Complications were significantly associated with in-hospital mortality, LOS, and hospital charges even after adjusting for patient and hospital characteristics. CONCLUSION: Complications are prevalent and exert a considerable influence on outcomes following aortic and mitral valve replacements. Quality initiatives should focus on minimizing complications and improving processes of care that would enable complications to be better resolved if they occur.


Asunto(s)
Válvula Aórtica/cirugía , Cardiopatías/etiología , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Válvula Mitral/cirugía , Anciano , Femenino , Cardiopatías/economía , Cardiopatías/mortalidad , Enfermedades de las Válvulas Cardíacas/economía , Enfermedades de las Válvulas Cardíacas/mortalidad , Implantación de Prótesis de Válvulas Cardíacas/economía , Implantación de Prótesis de Válvulas Cardíacas/estadística & datos numéricos , Costos de Hospital , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Prevalencia , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Estados Unidos/epidemiología
10.
Appl Radiat Isot ; 63(5-6): 645-53, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16005238

RESUMEN

Research investigating the application of pressure-cycled bubble chambers to fast neutron detection is described. Experiments with a Halon-filled chamber showed clear sensitivity to an AmBe neutron source and insensitivity to a (137)Cs gamma source. Bubble formation was documented using high-speed photography, and a ceramic piezo-electric transducer element registered the acoustic signature of bubble formation. In a second set of experiments, the bubble nucleation response of a Freon-134a chamber to an AmBe neutron source was documented with high-speed photography.

11.
J Chem Phys ; 120(17): 8241-52, 2004 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15267744

RESUMEN

We present a generalized crossover (GC) model for the excess adsorption of pure fluids at a flat solid-liquid interface, which reproduces scaling behavior of the excess adsorption in the critical region and is reduced to the classical, van der Waals-type analytical model far away from the bulk critical point. In developing this model, we used the density-functional theory (DFT) approach for the order parameter profile calculations with a generalized corresponding states model for the local free-energy density. The GC DFT model well represents the available experimental adsorption data for Kr/graphite, C2H4/graphite, C3H8/graphite, CO2/silica, and SF6/graphite systems in the entire density range 0 < rho < or = 3rhoc and temperatures up to 1.7Tc. In the critical region 0.5 rhoc < r < or = 1.5rhoc and T < or = 1.15Tc, the GC DFT model is consistent with the predictions of the asymptotic renormalization-group crossover model for the critical adsorption in a semi-infinite system developed earlier. For the excess adsorption on the critical isochore, both theories predict a scaling-law behavior Gamma proportional tau(-nu+beta), but fail to reproduce a "critical depletion" of the excess adsorption along the critical isochore of the SF6/graphite system near Tc. We show that an anomalous decrease of adsorption observed in this system at tau = T/Tc - 1 < 10(-2) can be explained by finite-size effect and develop a simplified crossover droplet (SCD) model for the excess adsorption in a slit pore. With the effective size of the pore of L = 50 nm, the SCD model reproduces all available experimental data for SF6/graphite, including the critical isochore data where tau-->0, within experimental accuracy. At L >> xib (where xib is a bulk correlation length) the SCD model is transformed into the GC DFT model for semi-infinite systems. Application of the SCD model to the excess adsorption of carbon dioxide on the silica gel is also discussed.

12.
J Chem Phys ; 120(18): 8676-82, 2004 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-15267797

RESUMEN

The thermal conductivity of molten sodium chloride and potassium chloride has been computed through equilibrium molecular dynamics Green-Kubo simulations in the microcanonical ensemble (N,V,E). In order to access the temperature dependence of the thermal conductivity coefficient of these materials, the simulations were performed at five different state points. The form of the microscopic energy flux for ionic systems whose Coulombic interactions are calculated through the Ewald method is discussed in detail and an efficient formula is used by analogy with the methods used to evaluate the stress tensor in Coulombic systems. The results show that the Born-Mayer-Huggins-Tosi-Fumi potential predicts a weak negative temperature dependence for the thermal conductivity of NaCl and KCl. The simulation results are in agreement with part of the experimental data available in the literature with simulation values generally overpredicting the thermal conductivity by 10%-20%.

13.
Phys Rev Lett ; 92(1): 012005, 2004 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-14753985

RESUMEN

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions including those for three sea quark flavors were extracted from these data together with reanalyzed previous data for identified pions from a hydrogen target. These distributions are consistent with zero for all three sea flavors. A recently predicted flavor asymmetry in the polarization of the light quark sea appears to be disfavored by the data.

14.
Phys Rev Lett ; 90(9): 092002, 2003 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-12689215

RESUMEN

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were scattered off a longitudinally polarized hydrogen target for values of Q2 between 1.2 and 12 GeV2 and values of W2 between 1 and 4 GeV2. The average double-spin asymmetry in the nucleon resonance region is found to agree with that measured in deep-inelastic scattering at the same values of the Bjorken scaling variable x. This finding implies that the description of A1 in terms of quark degrees of freedom is valid also in the nucleon resonance region for values of Q2 above 1.6 GeV2.

15.
Phys Rev Lett ; 90(5): 052501, 2003 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-12633347

RESUMEN

Exclusive coherent and incoherent electroproduction of the rho(0) meson from 1H and 14N targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared four-momentum of the virtual photon (-Q2). The ratio of 14N to 1H cross sections per nucleon, called nuclear transparency, was found to increase (decrease) with increasing l(c) for coherent (incoherent) rho(0) electroproduction. For fixed l(c), a rise of nuclear transparency with Q2 is observed for both coherent and incoherent rho(0) production, which is in agreement with theoretical calculations of color transparency.

18.
Med Hypotheses ; 57(5): 570-2, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11735312

RESUMEN

Ubiquinones (coenzyme Qs (CoQ)) are essential for oxidative phosphorylation in yeasts and humans, although the isomers present in each are different. The human coenzyme Q, CoQ10, is administered orally for the treatment of heart disease and other disorders. Some patients, however, require much higher doses than others to attain a therapeutic CoQ10 blood level. We propose that one possible explanation for this variability is Candida colonization of the GI tract. Many common medical treatments including antibiotics and anti-hyperchlorhydric agents increase the risk of GI tract Candida colonization. Subsequent uptake and utilization of supplemental CoQ10 by the yeast could diminish availability for the human subject. Data from one patient and an in vitro pilot study using two pathogenic strains of C. albicans support this hypothesis. If C. albicans in the GI tract can hinder availability and interfere with therapeutic effects of CoQ10, it could be of clinical significance for large numbers of patients.


Asunto(s)
Candida albicans/fisiología , Sistema Digestivo/microbiología , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo , Coenzimas , Humanos , Absorción Intestinal , Proyectos Piloto
20.
Inorg Chem ; 40(24): 6266-71, 2001 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-11703129

RESUMEN

A series of dinuclear (phosphine)gold(I) complexes of the ambidentate 1,3,4-thiadiazoledithiolate ligand (SSS) were prepared in high yield from the corresponding (phosphine)gold(I) chlorides and K(2)(SSS) in methanol. While mononuclear components (R(3)P)AuCl with R(3) = Ph(3), Ph(2)Py, or Me(3) (1-3) gave open-chain complexes, the dinuclear components ClAu(Ph(2)P-E-PPh(2))AuCl with E = (CH(2))(6), (C(5)H(4))Fe(C(5)H(4)), or 1,4-CH(2)C(6)H(4)CH(2) afforded cyclic complexes (4-6). The products have been characterized by analytical and spectroscopic methods, and the crystal structures of 1-4 have been determined by single-crystal X-ray techniques. Crystals of 1 [(CH(2)Cl(2))(2)] and 2 (CH(2)Cl(2)) contain the molecules aggregated in strings with long and probably very weak intermolecular Au.S contacts. The P-Au-S groups are aligned parallel head-to-tail and shifted in opposite directions to reduce steric conflicts, thus ruling out aurophilic Au...Au bonding. By contrast, in crystals of 3 (CH(2)Cl(2)) with smaller tertiary phosphine ligands, the molecules are aggregated via short [3.0089(3) and 3.1048(5) A] and probably strong aurophilic bonding to give a two-dimensional network with tetranuclear units formed from four (Me(3)P)AuS moieties of four different molecules as the connecting elements. In these tetranuclear units [(Me(3)P)AuS-](4), the P-Au-S axes are rotated against each other ("crossed swords") by 108.5 degrees (P2-Au2...Au2'-P2') or 116.9 degrees (P2-Au2...Au1'-P1'), respectively, to minimize steric conflicts. There is also significant bending of the P-Au-S axes to bring the metal atoms closer together: P1-Au1-S1 = 171.88(8) degrees and P2-Au2-S2 = 165.52(8) degrees. In the crystals of the cyclic complex 4 which contain no solvent molecules, the molecular units are aggregated in strings with short closed-shell interactions between the gold atoms of neighboring molecules [3.1898(3) A]. Because of the metallocyclic structure, the shielding of the gold atoms is reduced to allow aurophilic bonding as the P-Au-S groups are rotated against each other (crossed) by a dihedral angle P-Au...Au-P of 74.6 degrees.

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