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2.
Allergol Immunopathol (Madr) ; 43(3): 286-91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25097023

RESUMEN

INTRODUCTION: Anaphylaxis is the most severe of all allergic reactions and can even prove fatal. There is limited evidence of a difference in prescribing patterns for self-injectable epinephrine (SIE) between general paediatricians and paediatricians with greater knowledge of allergology. OBJECTIVES: Assess knowledge about prescribing SIE of a sample of primary care/hospital paediatricians and paediatricians with specialised knowledge of allergology through a questionnaire asking them about clinical cases of anaphylaxis in their daily paediatric practice. MATERIALS AND METHODS: Participants were primary care and hospital paediatricians practicing in different regions of the province of Barcelona and paediatricians with specialised knowledge in the field of allergology from Spain. RESULTS: A total of 183 paediatricians responded. Of that 59.6% were paediatricians with specialised knowledge of allergology. General paediatricians in most cases correctly prescribed SIE device (more than 70% answered correctly in five of the eight clinical cases). In the case of drug anaphylaxis, which is an avoidable allergen for which SIE is not indicated, 67.5% of general paediatricians would prescribe it. In the case of exercise-induced anaphylaxis there were also differences in the prescription of epinephrine by general paediatricians, with only 40% prescribing it. CONCLUSIONS: In this study the percentage of SIE prescriptions would be higher than expected by general paediatricians, with no differences in the cases proposed between them and the paediatricians with better knowledge of allergology. Despite these results, it is important to insist on conducting education programmes and disseminating them to facilitate physicians' recognition and treatment of anaphylactic reactions.


Asunto(s)
Alergia e Inmunología , Anafilaxia/epidemiología , Competencia Clínica/estadística & datos numéricos , Hipersensibilidad/epidemiología , Pautas de la Práctica en Medicina/estadística & datos numéricos , Anafilaxia/etiología , Anafilaxia/prevención & control , Epinefrina/administración & dosificación , Hospitales Especializados , Humanos , Hipersensibilidad/complicaciones , Hipersensibilidad/tratamiento farmacológico , Difusión de la Información , Pediatría , Médicos/estadística & datos numéricos , Atención Primaria de Salud , Autoadministración , España
4.
Science ; 262(5138): 1414-6, 1993 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-17736821

RESUMEN

Sagittarius (Sgr) A(*) is a unique radio source located at the center of our galaxy. The radiation from Sgr A(*) may be generated in matter accreting onto a massive black hole. In observations at long wavelengths, the apparent angular size of Sgr A(*) decreases in the manner expected for emission from a point source scattered by electron density fluctuations along the line of sight. Measurements at a wavelength of 7 millimeters with the nearly completed Very Long Baseline Array indicate a size of 0.7 milliarc seconds, which is consistent with an extrapolation from results at longer wavelengths. The true size of Sgr A(*) must be less than 0.4 milliarc seconds, or 3.3 astronomical units. The inferred black hole mass is less than 1.5 x 10(6) solar masses according to a recent model for the emission.

5.
Science ; 157(3789): 676-7, 1967 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-17792848

RESUMEN

An upper limit of 0.02 second of arc has been determined for a hydroxyl radical (OH) emission region associated with the radio source W3, with the use of a Michelson interferometer consisting of two radio telescopes 845 kilometers apart. Timing was provided at the stations by independent atomic frequency standards. The 1665-megahertz radiation was translated to video frequency and recorded digitally on magnetic tapes which were later processed by computer, yielding fringe phase and amplitude as a function of frequency over the received bandwidth.

6.
Science ; 178(4059): 396-8, 1972 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-17815361

RESUMEN

Very-long-baseline interferometry experiments, involving observations of extragalactic radio sources, were performed in 1969 to determine the vector separations between antenna sites in Massachusetts and West Virginia. The 845.130-kilometer baseline was estimated from two separate experiments. The results agreed with each other to within 2 meters in all three components and with a special geodetic survey to within 2 meters in length; the differences in baseline direction as determined by the survey and by interferometry corresponded to discrepancies of about 5 meters. The experiments also yielded positions for nine extragalactic radio sources, most to within 1 arc second, and allowed the hydrogen maser clocks at the two sites to be synchronized a posteriori with an uncertainty of only a few nanoseconds.

9.
Theriogenology ; 70(1): 91-6, 2008 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-18433854

RESUMEN

Nitric oxide (NO) is a highly reactive free radical that plays a key role in intra- and intercellular signaling. Production of radical oxygen species and an apoptotic-like phenomenon have recently been implicated in cryodamage during sperm cryopreservation. The objective of the present study was to evaluate the effect of sodium nitroprusside (SNP), an NO donor, on boar sperm viability. Semen samples were pooled from four boars that were routinely used for artificial insemination. Flow cytometry was used to compare semen incubated with SNP to control semen. Specifically, NO production was measured using the NO indicator dye diaminofluorescein diacetate, and caspase activity was determined using the permeable pan-caspase inhibitor Z-VAD linked to FITC. SNP induced a significant increase in the percentage of sperm cells showing caspase activity, from 9.3% in control samples to 76.2% in SNP-incubated samples (P<0.01). This study suggests that NO is a major free radical involved in boar sperm damage.


Asunto(s)
Caspasas/metabolismo , Depuradores de Radicales Libres/farmacología , Óxido Nítrico/farmacología , Espermatozoides/efectos de los fármacos , Espermatozoides/enzimología , Porcinos/fisiología , Animales , Apoptosis/efectos de los fármacos , Masculino , Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/farmacología , Nitroprusiato/farmacología , Triterpenos Pentacíclicos , Triterpenos/farmacología , Ácido Betulínico
10.
Med Phys ; 45(10): e793-e810, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30226286

RESUMEN

The term Big Data has come to encompass a number of concepts and uses within medicine. This paper lays out the relevance and application of large collections of data in the radiation oncology community. We describe the potential importance and uses in clinical practice. The important concepts are then described and how they have been or could be implemented are discussed. Impediments to progress in the collection and use of sufficient quantities of data are also described. Finally, recommendations for how the community can move forward to achieve the potential of big data in radiation oncology are provided.


Asunto(s)
Bases de Datos Factuales , Informática Médica/métodos , Neoplasias/terapia , Oncología por Radiación/estadística & datos numéricos , Minería de Datos , Humanos , Almacenamiento y Recuperación de la Información , Motivación , Estadificación de Neoplasias , Neoplasias/diagnóstico , Neoplasias/patología
11.
Theriogenology ; 68(2): 196-203, 2007 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-17555808

RESUMEN

Although sperm head shape and relative dimensions are considered reliable indicators of sperm quality, their quantification is most often operator-driven, e.g., subjective. Artificial insemination semen doses from 35 mature stud boars of known fertility and belonging to three breeds and two hybrid breeds (Duroc, Large White, Landrace, respectively, Yorker and Risco) were used in this study. Sperm samples were extended to 100x10(6) cells per mL and 10microL of the sperm suspension used to made smears which, stained, were examined using phase contrast microscopy interfaced with an automated sperm morphology analyzer (ASMA, ISAS). Each sperm head was measured for four primary parameters [area (A) microm(2), perimeter (P) mum, length (L) microm, width (W) microm], and four derived parameters of head shape [(L/W), (4piA/P(2)), ((L-W)/(L+W)), (piLW/4A)]. Definition of head size was statistically performed. The threshold for each class was established on the basis of the area values, considering the 25th percentile as small and the 75th percentile as large spermatozoa. In a second step, sperm head shape was determined as normal, elliptic, abnormal (rugose) contour, long or irregular and percentiles set as above to define spermatozoa with normal values for each shape parameter. Significant differences were found among breeds in the size of morphologically normal spermatozoa, which were significantly larger and more elliptic (P<0.001) in the Duroc breed. Sperm chromatin integrity was studied using the SCSA-assay, with significant differences observed in the degree of fragmentation intensity (DFI) although this value was consistently low in all animals studied. The hereby-validated ASMA was able to determine significant differences in sperm shape and dimensions among breeds, which were not accompanied by deviations in chromatin structure neither within nor between fertile AI-boars.


Asunto(s)
Cromatina/ultraestructura , Espermatozoides/citología , Porcinos , Animales , Fragmentación del ADN , Procesamiento de Imagen Asistido por Computador , Masculino , Programas Informáticos , Espermatozoides/clasificación
12.
Reprod Domest Anim ; 41 Suppl 2: 21-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16984466

RESUMEN

Pure dog breeding is experiencing growing interest. Assisted reproductive technologies are each time demanded more by the small animal practitioner. In this paper different semen technologies are briefly reviewed under the perspective of the authors. In addition, new trends in the evaluation of canine ejaculates, developed in the laboratory of the authors are discussed. The existence of sperm subpopulations defined based both on kinematics and morphometric characteristics of the spermatozoa is now widely accepted by the scientific community. In the laboratory of the authors new, simpler and more straightforward statistical tools have been used to disclose the sperm subpopulation structure in the canine ejaculate. The study of the sperm subpopulation structure and its changes after cryopreservation has allowed us to gain an insight into the differences in freezeability among dogs, and also predict to a great extent the outcome of a cryopreservation procedure of a given semen sample. New techniques to evaluate early membrane changes have also been recently developed in our laboratory.


Asunto(s)
Cruzamiento/métodos , Perros/fisiología , Preservación de Semen/veterinaria , Manejo de Especímenes/veterinaria , Espermatozoides/ultraestructura , Animales , Criopreservación/veterinaria , Femenino , Inseminación Artificial/veterinaria , Masculino , Preservación de Semen/métodos , Manejo de Especímenes/métodos , Motilidad Espermática/fisiología , Espermatozoides/citología , Espermatozoides/fisiología
13.
Med Phys ; 43(8): 4789, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27487896

RESUMEN

PURPOSE: To develop a comprehensive peripheral dose (PD) dataset for the two unflattened beams of nominal energy 6 and 10 MV for use in clinical care. METHODS: Measurements were made in a 40 × 120 × 20 cm(3) (width × length × depth) stack of solid water using an ionization chamber at varying depths (dmax, 5, and 10 cm), field sizes (3 × 3 to 30 × 30 cm(2)), and distances from the field edge (5-40 cm). The effects of the multileaf collimator (MLC) and collimator rotation were also evaluated for a 10 × 10 cm(2) field. Using the same phantom geometry, the accuracy of the analytic anisotropic algorithm (AAA) and Acuros dose calculation algorithm was assessed and compared to the measured values. RESULTS: The PDs for both the 6 flattening filter free (FFF) and 10 FFF photon beams were found to decrease with increasing distance from the radiation field edge and the decreasing field size. The measured PD was observed to be higher for the 6 FFF than for the 10 FFF for all field sizes and depths. The impact of collimator rotation was not found to be clinically significant when used in conjunction with MLCs. AAA and Acuros algorithms both underestimated the PD with average errors of -13.6% and -7.8%, respectively, for all field sizes and depths at distances of 5 and 10 cm from the field edge, but the average error was found to increase to nearly -69% at greater distances. CONCLUSIONS: Given the known inaccuracies of peripheral dose calculations, this comprehensive dataset can be used to estimate the out-of-field dose to regions of interest such as organs at risk, electronic implantable devices, and a fetus. While the impact of collimator rotation was not found to significantly decrease PD when used in conjunction with MLCs, results are expected to be machine model and beam energy dependent. It is not recommended to use a treatment planning system to estimate PD due to the underestimation of the out-of-field dose and the inability to calculate dose at extended distances due to the limits of the dose calculation matrix.


Asunto(s)
Fotones/uso terapéutico , Dosis de Radiación , Planificación de la Radioterapia Asistida por Computador/métodos , Algoritmos , Humanos , Dosificación Radioterapéutica
16.
Am J Med ; 62(5): 687-92, 1977 May.
Artículo en Inglés | MEDLINE | ID: mdl-300989

RESUMEN

Thirty-seven patients in cardiogenic shock due to acute myocardial infarction were treated with intraaortic balloon counterpulsation and/or surgery. Eighteen of these patients were treated with counterpulsation alone; eight survived and five were in functional class I or II at the time of follow-up; two were in functional class III, and one was in functional class IV. Nineteen patients were treated surgically, eight survived and seven were in functional class I or II at the time of follow-up; one was in functional class III. Good functional recovery with counterpulsation alone is most common with inferior infarction. With surgery, functional recovery depends not only on the extent of the infarction and the coronary anatomy, but also on the ability to perform surgery within 12 hours of infarction or to support the patient with mechanical means for 10 to 14 days after the infarction and then perform surgery.


Asunto(s)
Circulación Asistida , Contrapulsador Intraaórtico , Infarto del Miocardio/complicaciones , Choque Cardiogénico/terapia , Adulto , Anciano , Puente de Arteria Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/cirugía , Choque Cardiogénico/etiología , Choque Cardiogénico/cirugía
17.
Am J Cardiol ; 48(4): 690-7, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7282550

RESUMEN

Although the existence of a specific pacemaker hierarchy outside of the sinus node but within the atrium has been documented, little evidence regarding mechanisms controlling activity of these sites has been gathered. This investigation utilized an autologous perfusion of the sinus nodal artery, by way of the femoral artery, in order to suppress the sinus node cholinergically while unmasking latent atrial sites. Electrograms were recorded from the region of the sinus node and several atrial sites. Perfusion with small doses of acetylcholine and physostigmine unmasked pacemakers outside of the sinus and atrioventricular nodes, but within the atrium. Either vagal stimulation or topical acetylcholine on the area of the presumed pacemaker returned dominance gradually toward the sinus node. Stimulation of the right stellate ganglion accelerated the latent pacemaker but did not shift activation toward the sinus node. These results are consistent with the existence of subsidiary atrial pacemakers that appear to be highly sensitive to the effects of acetylcholine. This may represent one mechanism, in addition to overdrive suppression, that maintains pacemaker hierarchy within the right atrium.


Asunto(s)
Sistema Nervioso Autónomo/fisiología , Atrios Cardíacos/inervación , Sistema de Conducción Cardíaco/fisiología , Nodo Sinoatrial/fisiología , Acetilcolina/fisiología , Animales , Nodo Atrioventricular/fisiología , Perros , Femenino , Masculino , Ganglio Estrellado/fisiología , Nervio Vago/fisiología
18.
Am J Cardiol ; 37(6): 878-84, 1976 May.
Artículo en Inglés | MEDLINE | ID: mdl-1266754

RESUMEN

Krypton-81m, a radionuclide emitting a 190 kev gamma ray, has a half-life of 13 seconds. It is a radioisotope of an inert water-soluble noble gas and is produced at a constant rate by spontaneous decay of rubidium-81 in an 81Rb-81mKr generator-delivery system. Delivery is through a minibore Teflon catheter that can be threaded through a standard no. 7 or 8F angiographic catheter. The generator is eluted by 5 percent dextrose-in-water, delivered by infusion pump at 1.5 ml/min, and the eluate is infused intraarterially directly into any organ. Delivery and decay reach equilibrium within 2 minutes, producing a heterogeneous distribution that is proportional to the perfusibility of the tissue concerned and the time required to reach it. The ultrashort halflife of the radionuclide rapidly eliminates activity when delivery ceases; thus, experiments can be sequentially repeated at brief intervals. The radiation hazard for easily imaged doses is negligible. Preliminary studies in open chest dogs were visualized by scintillation camera, stored on digital data disk, processed, and displayed in dual channel, dual color mode on a video system. Images of myocardial perfusion defined relative levels of perfusion, collateral circulation between coronary arterial branches, equilibrium time of diffusible perfusion of the myocardium, focal defects in induced occlusion, collateral circulation to occlusion, and reactive hyperemia after release of induced coronary occlusion. The system and technique appear applicable to human subjects.


Asunto(s)
Vasos Coronarios , Criptón , Radioisótopos , Cintigrafía/métodos , Animales , Circulación Colateral , Perros , Monitoreo Fisiológico , Perfusión , Televisión
19.
Am J Cardiol ; 55(8): 1076-83, 1985 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-3984870

RESUMEN

The relation between endocardial activation mapping and endocardial pace-mapping was evaluated in 8 dogs while they were on cardiopulmonary bypass. Pacing or recording was accomplished by using a balloon apparatus (with 32 bipolar electrodes) inserted through a left apical ventriculotomy. Ventricular tachycardia (VT) was produced by occlusion followed by reperfusion of the left anterior descending coronary artery. During each VT, activation mapping was performed and early sites determined. Pace-map correlates (sites at which endocardial pacing produced a similar QRS morphology to that of the VT) were also determined. Isochronous maps were constructed for activation mapping and pace-mapping. There was a total of 29 morphologically distinct VTs. Groups were delineated according to correlations between activation mapping and pace-mapping. In 14 episodes of VT (group 1), pace-mapping confirmed the findings of activation mapping with all early sites being pace-map correlates (total number of early sites (tES) = 19; total number of pace-map correlates (tPMC) = 88; tES same as tPMC = 19). In 9 episodes of VT (group 2), there was a partial correlation between pace-mapping and activation mapping, such that pace-mapping when used with activation mapping appeared to further delineate the region of arrhythmogenesis (tES = 31; tPMC = 59; tES same as tPMC = 14). In 6 episodes of VT (group 3), there was no correlation between pace-mapping and activation mapping (tES = 15; tPMC = 0). With the balloon apparatus, endocardial activation mapping can be performed without the need for sustained monomorphic VT, and endocardial pace-maps may be generated easily.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Arritmias Cardíacas/fisiopatología , Cateterismo Cardíaco/instrumentación , Estimulación Cardíaca Artificial , Endocardio/fisiopatología , Animales , Arritmias Cardíacas/cirugía , Perros , Electrocardiografía , Ventrículos Cardíacos/fisiopatología , Periodo Intraoperatorio , Taquicardia/fisiopatología , Taquicardia/cirugía
20.
J Thorac Cardiovasc Surg ; 81(3): 428-32, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6970307

RESUMEN

Simultaneous vertebral artery and coronary artery bypass are reported in a patient with unstable angina who exhibited signs and symptoms of vertebrobasilar insufficiency while awaiting myocardial revascularization. The indications and various technical options for vertebral artery bypass are reviewed, and the techniques applied in this case are described. Observations on coronary and vertebral vein graft flow, with and without intra-aortic balloon counterpulsation, are presented. Late patency of the aortovertebral vein graft has been documented, and the patient has been free from symptoms of vertebrobasilar and coronary insufficiency for 5 years.


Asunto(s)
Angina de Pecho/cirugía , Puente de Arteria Coronaria/métodos , Arteria Vertebral/cirugía , Insuficiencia Vertebrobasilar/cirugía , Angina de Pecho/complicaciones , Aorta Torácica/cirugía , Arterias Carótidas/diagnóstico por imagen , Humanos , Masculino , Métodos , Persona de Mediana Edad , Radiografía , Arteria Vertebral/diagnóstico por imagen , Insuficiencia Vertebrobasilar/complicaciones
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