Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 91
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Phys Rev Lett ; 116(2): 022701, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26824536

RESUMEN

Neutron-rich {96,98}Sr isotopes have been investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross sections. These results allow, for the first time, the drawing of definite conclusions about the shape coexistence of highly deformed prolate and spherical configurations. In particular, a very small mixing between the coexisting states is observed, contrary to other mass regions where strong mixing is present. Experimental results have been compared to beyond-mean-field calculations using the Gogny D1S interaction in a five-dimensional collective Hamiltonian formalism, which reproduce the shape change at N=60.

3.
Phys Rev Lett ; 106(5): 052503, 2011 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-21405388

RESUMEN

In-source resonant ionization laser spectroscopy of the even-A polonium isotopes (192-210,216,218)Po has been performed using the 6p(3)7s (5)S(2) to 6p(3)7p (5)P(2) (λ=843.38 nm) transition in the polonium atom (Po-I) at the CERN ISOLDE facility. The comparison of the measured isotope shifts in (200-210)Po with a previous data set allows us to test for the first time recent large-scale atomic calculations that are essential to extract the changes in the mean-square charge radius of the atomic nucleus. When going to lighter masses, a surprisingly large and early departure from sphericity is observed, which is only partly reproduced by beyond mean field calculations.

4.
Phys Rev Lett ; 105(25): 252502, 2010 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-21231583

RESUMEN

A very exotic process of ß-delayed fission of 180Tl is studied in detail by using resonant laser ionization with subsequent mass separation at ISOLDE (CERN). In contrast to common expectations, the fission-fragment mass distribution of the post-ß-decay daughter nucleus 180Hg (N/Z=1.25) is asymmetric. This asymmetry is more surprising since a mass-symmetric split of this extremely neutron-deficient nucleus would lead to two 90Zr fragments, with magic N=50 and semimagic Z=40. This is a new type of asymmetric fission, not caused by large shell effects related to fragment magic proton and neutron numbers, as observed in the actinide region. The newly measured branching ratio for ß-delayed fission of 180Tl is 3.6(7) × 10(-3)%, approximately 2 orders of magnitude larger than in an earlier study.

5.
Phys Rev Lett ; 105(25): 252501, 2010 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-21231582

RESUMEN

The "island of inversion" nucleus 32 Mg has been studied by a (t, p) two neutron transfer reaction in inverse kinematics at REX-ISOLDE. The shape coexistent excited 0+ state in 32 Mg has been identified by the characteristic angular distribution of the protons of the Δ L=0 transfer. The excitation energy of 1058 keV is much lower than predicted by any theoretical model. The low γ-ray intensity observed for the decay of this 0+ state indicates a lifetime of more than 10 ns. Deduced spectroscopic amplitudes are compared with occupation numbers from shell-model calculations.

6.
Curr Med Res Opin ; 3(3): 151-6, 1975.
Artículo en Inglés | MEDLINE | ID: mdl-1149483

RESUMEN

'Pregnon', a new oral contraceptive containing 1 mg. lynestrenol and 0.05 mg. ethinyl oestradiol, was administered cyclically to 639 women of fertile age over a total of 9,159 cycles. There were no pregnancies. In most cases the withdrawal bleeding resembled normal menstruation. The incidence of metrorrhagia was relatively low and when it did occur it was usually confined to the early treatment cycles and was of very limited duration. The objective and subjective tolerance was excellent.


PIP: Pregnon is a new low-dosage ovulation-inhibiting agent containing 1 mg of lynestrenol and .05 mg of ethinyl estradiol in each tablet. It is also marketed under the name of Pregnon 28 or Ovostat 28 in which each package contains 22 active plus 6 placebo tablets. Data were collected from Belgian clinics and evaluated by the Medical Unit of Organon in Belgium and the Netherlands. During this study, 639 women of fertile age were monitored through 9159 cycles. The maximum period of treatment was 36 cycles. Clinical and gynecological examinations were made before treatment and then every 2 or 3 months. Treatment was begun by taking the 1st tablet on the 1st day of menstruation. After taking 22 tablets there was a 6-day tablet-free interval during which withdrawal bleeding usually occurred. The intensity of the withdrawal bleeding was normal in 57.3%, slight in 41.7%, and heavy in 1%. Spotting was noted in 3.1% of the cycles and breakthrough bleeding occurred in 2.9%. Usually they occurred in the first 3 cycles. Amenorrhea was observed in 2.9% of the cycles. Body weights were relatively unchanged. Blood pressures remained the same. Side effects were headache, nausea, vomiting, breast tenderness, heavy legs, leucorrhea, nervousness, depression, and decreased libido. Only 46 patients discontinued treatment because of these drug effects yielding an acceptability level of about 93%. Since no pregnancies occurred during this study, the Pearl index was 0.


Asunto(s)
Anticonceptivos Sintéticos Orales , Anticonceptivos Orales , Etinilestradiol , Linestrenol , Adolescente , Adulto , Amenorrea/inducido químicamente , Combinación de Medicamentos , Evaluación de Medicamentos , Tolerancia a Medicamentos , Etinilestradiol/efectos adversos , Femenino , Humanos , Linestrenol/efectos adversos , Menorragia/inducido químicamente , Embarazo
7.
Phys Med Biol ; 48(3): 371-85, 2003 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-12608613

RESUMEN

A new component module (CM), called MLCE, has been implemented in the BEAM program. The CM takes into account the particular 'tongue-and-groove' design of the Elekta multi-leaf collimator (MLC) and the air gap between the leaves. The model was validated by two series of measurements and simulations. The first benchmarking series focuses on the interleaf leakage and the intraleaf transmission. The measurement showed a total transmission through the MLC of 1.42% of the open field dose. Two Monte Carlo (MC) simulations were made, the first with the new CM MLCE (inclusive of air gap) and the second with the CM MLCQ (exclusive of air gap), which is available in the BEAM distribution. When the air gap between the leaves was determined by varying the parameters of the leaf geometry within tolerance limits on the technical drawing, the total measured transmission of 1.42% was well reproduced by the CM MLCE. In contrast, MC simulations with MLCQ showed that the transmission through the MLC calculated without the interleaf leakage is only 44% of the total transmitted radiation. The relevance of the detailed MLC modelling was demonstrated also by studying the 'adjacent' tongue-and-groove effect, where two adjacent (not opposing) leaves are complementary, opened or closed. The two complementary leaf settings were simulated both with the CM MLCE and MLCQ. A comparison with measurements was made. In regions covered by two or more leaves, the dose increased by 14% for two leaves and by 40% for more than two leaves when the interleaf leakage was included in the transmission. The tongue-and-groove effect was perfectly reproduced by the MLCE module.


Asunto(s)
Algoritmos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/instrumentación , Radioterapia Conformacional/métodos , Diseño de Equipo , Análisis de Falla de Equipo/métodos , Método de Montecarlo , Control de Calidad , Radiometría , Dosificación Radioterapéutica , Dispersión de Radiación , Validación de Programas de Computación
8.
Contraception ; 22(5): 537-48, 1980 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7009054

RESUMEN

PIP: Fysioquens, a new contraceptive based on the normophasic scheme (0.050 mg [EE] ethinyl estradiol for the first 7 days followed by 0.050 mg EE and 1 mg lynestrenol for 15 days) was administered to 120 patients for a total of 2281 cycles. No pregnancies and/or dropouts were recorded. Cycle control was very good and the incidence of irregular bleedings was low (1.6%). Endometrial biopsies taken on cycle day 9-11 (tablet day 5-7) from 50 Fysioquens patients treated for more than 2 years were compared blindly to 50 biopsies taken on cycle 9-14 from 50 controls (without hormonal therapy). Some anomalies were observed in both groups with similar incidence (Fysioquens 10/50; Control 7/50). A 2nd biopsy taken 6 months later on cycle day 24-26 (tablet day 20-22) in the 100 Fysioquens patients with some endometrial anomalies on tablet day 5-7 revealed that this abnormal picture had spontaneously disappeared without interruption of treatment. The stereomorphometric comparison between the 10 abnormal Fysioquens biopsies taken in the 1st part of the cycle and 6 normal biopsies showed a significant increase in glandular diameter and in % volume of glandular lumen. The stereomorphometric study of the 10 biopsies taken 6 treatment cycles later on cycle day 24-26 (tablet day 20-22) in comparison with 7 normal control biopsies revealed a very significant decrease in glandular diameter, glandular lumen, and glandular volume, resulting in a very significant increase in stroma. It is consequently concluded that the abnormal biopsies observed in the beginning of the cycle in some treated patients is due only to a transitory estrogenic effect and that the early administration of progestagen in the normophasic dosage scheme not only counteracts this effect but could play a protective role against hyperplasia.^ieng


Asunto(s)
Anticonceptivos Secuenciales Orales/administración & dosificación , Anticonceptivos Orales/administración & dosificación , Etinilestradiol/administración & dosificación , Linestrenol/administración & dosificación , Adulto , Ensayos Clínicos como Asunto , Anticonceptivos Secuenciales Orales/efectos adversos , Hiperplasia Endometrial/inducido químicamente , Etinilestradiol/efectos adversos , Femenino , Humanos , Linestrenol/efectos adversos
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(2 Pt 2): 026606, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14995579

RESUMEN

The Mie scattering intensity of a magnetic sphere has been derived by extending the classical Mie scattering approach to a media where the dielectric constant is no more a real number but a tensor with a gyrotropic form. Using a perturbation method the propagation equations of the electromagnetic field are derived. For an incident plane wave the magnetization effect could be detectable. The Mie scattering intensity is analyzed for special incident wave configurations, in particular, for the case where the magnetic field of the incident plane wave is polarized along the magnetization direction. This magnetization effect is most important for the finger pattern of the backscattering intensity. Magnetic Mie scattering is still significant for a magnetic sphere of radius larger than 10 nm.

10.
Nucl Med Commun ; 19(2): 149-54, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9548199

RESUMEN

We performed a retrospective study to determine the age- and sex-related normal values of absolute 99Tcm-DMSA uptake at 24 h in children with normal kidneys. Of the 576 scintigrams performed between 1993 and 1996, 136 (272 kidneys) were classified as 'normal' by two independent observers on the basis of the presence of a smooth cortical outline, the absence of cortical loss, relative uptake in the range 45-55% and normal echographic parenchymal findings. The 136 scintigrams were divided into eight groups based on the children's age: Group I, < 1 month (2 boys); Group II, 1-3 months (6 boys, 8 girls); Group III, 4-7 months (7 boys, 6 girls); Group IV, 8-12 months (8 boys, 8 girls); Group V, 13-24 months (14 boys, 4 girls); Group VI, 25-36 months (6 boys, 13 girls); Group VII, 37-120 months (13 boys, 19 girls); Group VIII, 121-180 months (8 boys, 10 girls). In contrast to the results of Morris et al. using absolute 99Tcm-DMSA uptake at 4-6 h, we found that combined left and right kidney uptake increased until age 8 months (Group I, 22.0 +/- 6.7%; Group II, 45.9 +/- 5.0%; Group III, 50.8 +/- 5.0%; Group IV, 56.9 +/- 8.5%; P = 0.019), after which it reached a plateau (Group V, 55.4 +/- 7.3%; Group VI, 60.1 +/- 7.8%; Group VII, 62.0 +/- 5.0%; Group VIII, 62.4 +/- 6.3%). Uptake at 24 h tended to be lower in the girls than in the boys, but this difference was not significant.


Asunto(s)
Riñón/diagnóstico por imagen , Riñón/fisiología , Radiofármacos/farmacocinética , Ácido Dimercaptosuccínico de Tecnecio Tc 99m/farmacocinética , Adolescente , Factores de Edad , Envejecimiento , Transporte Biológico , Niño , Preescolar , Femenino , Humanos , Lactante , Riñón/anatomía & histología , Masculino , Cintigrafía , Valores de Referencia , Estudios Retrospectivos , Caracteres Sexuales , Distribución Tisular
11.
Arch Mal Coeur Vaiss ; 92(1): 57-60, 1999 Jan.
Artículo en Francés | MEDLINE | ID: mdl-10065283

RESUMEN

Chronic occlusion of the left main coronary artery is rare with less than 100 reported cases. the treatment is essentially surgical but medical management has been proposed. This case report illustrates the prognostic benefit of surgical management in view of the risk of secondary occlusion of the proximal right coronary artery.


Asunto(s)
Enfermedad Coronaria/diagnóstico , Revascularización Miocárdica , Enfermedad Crónica , Enfermedad Coronaria/cirugía , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
12.
Arch Mal Coeur Vaiss ; 87(1): 111-4, 1994 Jan.
Artículo en Francés | MEDLINE | ID: mdl-7811145

RESUMEN

Ischaemia has been the suggested mechanism of simultaneous left bundle branch block and chest pain on effort with normal coronary angiography. This hypothesis is very controversial and was not the mechanism in the two new cases of this syndrome. The two patients in whom effort pain and left bundle branch block were observed had been treated for paroxysmal supraventricular tachycardia with flecaine. Withdrawal of the anti-arrhtymic resulted in the disappearance of this syndrome. In these cases, the ischaemic mechanism could be excluded without ambiguity. The flecaine was the only cause of rate-related LBBB by slowing conduction in the left bundle branch with no effects on coronary reserve. It would seem that LBBB alone was the cause of chest pain. The absence of coronary artery disease was confirmed in the first patient and the diagnosis was highly improbable in the second.


Asunto(s)
Angina de Pecho/inducido químicamente , Bloqueo de Rama/inducido químicamente , Flecainida/efectos adversos , Anciano , Fibrilación Atrial/tratamiento farmacológico , Bloqueo de Rama/complicaciones , Angiografía Coronaria , Ejercicio Físico , Femenino , Flecainida/uso terapéutico , Humanos , Angina Microvascular/diagnóstico , Angina Microvascular/etiología , Persona de Mediana Edad
13.
Arch Mal Coeur Vaiss ; 87(2): 235-9, 1994 Feb.
Artículo en Francés | MEDLINE | ID: mdl-7802531

RESUMEN

The authors report four cases of cardiac amyloidosis, the diagnosis of which was confirmed by endomyocardial biopsy. They underline the value of immuno-histological studies with labelling of the biopsy fragments with anti-transthyretin and anti-light chain immunoglobulin antibodies. This approach provides a more precise typing of amyloidosis and a more accurate evaluation of the prognosis.


Asunto(s)
Amiloidosis/complicaciones , Cardiomiopatías/etiología , Adulto , Anciano , Amiloide/análisis , Amiloidosis/diagnóstico , Biopsia , Cardiomiopatías/diagnóstico , Endocardio/patología , Femenino , Insuficiencia Cardíaca/etiología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Miocardio/patología , Prealbúmina/inmunología , Pronóstico
14.
Arch Mal Coeur Vaiss ; 93(7): 875-8, 2000 Jul.
Artículo en Francés | MEDLINE | ID: mdl-10975041

RESUMEN

The thymic cysts are benign tumours of the thymo-pharyngeal canal, usually located in the cervico-mediastinal region. The authors report the case of a large thymic cyst with an ectopic right paracardiac location compressing the right heart chambers. It was a chance finding on chest X-ray of an asymptomatic 21 year old man. Though suggestive of a pericardial cyst in view of its position, curative surgical ablation allowed confirmation of the diagnosis at anatomo-pathological examination.


Asunto(s)
Quiste Mediastínico/patología , Adulto , Ecocardiografía , Atrios Cardíacos/patología , Ventrículos Cardíacos/patología , Humanos , Masculino , Quiste Mediastínico/diagnóstico por imagen , Quiste Mediastínico/cirugía , Radiografía Torácica
15.
Arch Mal Coeur Vaiss ; 91(4): 415-8, 1998 Apr.
Artículo en Francés | MEDLINE | ID: mdl-9749228

RESUMEN

The authors report the case of a 50 year old man with pseudowanthoma elastica with a history of myocardial infarction and severe aortic regurgitation. Angiography showed multiple coronary artery aneurysms and aneurysmal dilatation of the aortic annulus. The outcome after triple coronary bypass surgery with aortic valve replacement in a valved Bentall conduit was favourable. Pseudoxanthoma elastica is a rare condition in which the prognosis depends on the degree of vascular involvement. In this context, coronary artery aneurysms and aneurysmal dilatation of the aorta are rare complications.


Asunto(s)
Insuficiencia de la Válvula Aórtica/complicaciones , Aneurisma Coronario/complicaciones , Seudoxantoma Elástico/complicaciones , Insuficiencia de la Válvula Aórtica/diagnóstico , Insuficiencia de la Válvula Aórtica/cirugía , Aneurisma Coronario/diagnóstico , Aneurisma Coronario/cirugía , Angiografía Coronaria , Puente de Arteria Coronaria , Prótesis Valvulares Cardíacas , Humanos , Masculino , Persona de Mediana Edad
16.
Arch Mal Coeur Vaiss ; 91(3): 337-41, 1998 Mar.
Artículo en Francés | MEDLINE | ID: mdl-9749239

RESUMEN

Heart rate variability is a sign of sympathetic activity. The authors compared two study populations of young males aged 19 to 30 years: population T comprised 15 healthy volunteers who had two negative tilt tests, one under basal conditions and the other after a bolus of isoproterenol; population S comprised 12 patients without cardiac or other disease, who were followed up for malaise and in whom the basal tilt test was positive, confirming the vagal origin of syncope. Temporal and spectral (total power, low frequency 0.04-0.15 Hz, hight frequency 0.16-0.40 Hz) data was obtained concerning heart rate variability from 24 hour Holter monitoring. The main difference between the two study populations was in the temporal data over 24 hours especially with respect to the heart rate (T = 73.5 +/- 6.9; S = 65.4 +/- 6.2/min; p = 0.004) and the percentage of successive R-R intervals varying by more than 50 ms (PNN 50) (T = 20.2 +/- 8.3%; S = 30.7 +/- 10.2%; p = 0.024). At night, the lowest SDANN/5 (standard deviation of RR intervals over periods of 5 minutes) were observed in group S (67.2 +/- 16.7 ms vs 87.3 +/- 24.4 ms; p = 0.026). No statistically significant differences between the two groups was observed in the spectral data. The temporal data of heart rate variability on Holter ECG monitoring over 24 hours could therefore have a good predictive value of the vagal origin of syncope in young adults.


Asunto(s)
Frecuencia Cardíaca , Síncope Vasovagal/fisiopatología , Adulto , Electrocardiografía Ambulatoria , Humanos , Masculino , Pruebas de Mesa Inclinada
17.
Acta Anaesthesiol Belg ; 29(1): 91-3, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-707031

RESUMEN

Fatal anesthetic accidents still occur frequently. Origins and causes are being reviewed especially in the light of lawsuits against anesthetists. The importance of utmost continuous supervision and care for both the vital functions: respiration and circulation, is stressed. General recommendations for security during anesthesia are advanced.


Asunto(s)
Anestesia/normas , Anestesia/mortalidad , Competencia Clínica , Humanos , Seguridad
18.
Acta Anaesthesiol Belg ; 27(3): 187-91, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-801583

RESUMEN

Buprenorphine was used as an analgesic medication for patients at the pain clinic. Clinical observations on its long term administration for intractable pain are reported. A good analgesic activity was noted in most of the patients. Nausea and vomiting was the mean reason for cancellation of the therapy.


Asunto(s)
Analgésicos/uso terapéutico , Morfinanos/uso terapéutico , Dolor/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Analgésicos/administración & dosificación , Analgésicos/efectos adversos , Ensayos Clínicos como Asunto , Confusión/inducido químicamente , Depresión/inducido químicamente , Evaluación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Morfinanos/administración & dosificación , Morfinanos/efectos adversos , Náusea/inducido químicamente , Sueño/efectos de los fármacos , Sudoración/efectos de los fármacos , Factores de Tiempo , Vómitos/inducido químicamente
19.
Acta Anaesthesiol Belg ; 29(1): 37-43, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-707027

RESUMEN

The safety of the patient under anesthesia is directly correlated to the quality of the service delivered by the anesthetic department. A good organised work, supposes a staff, which accords to numerical and qualitative requirements. The number of personal required is a function of working conditions. The quality required for the persons who administer anesthesia, depends upon the intrinsic danger of the procedure. As the nature of anesthesia is still linked with the acute control of vital functions of the patient, the qualifications of the person who administer the narcosis should be of the highest level.


Asunto(s)
Servicio de Anestesia en Hospital/organización & administración , Anestesia/normas , Departamentos de Hospitales/organización & administración , Administración de Personal , Admisión y Programación de Personal , Competencia Clínica , Humanos , Seguridad , Recursos Humanos
20.
Acta Anaesthesiol Belg ; 31 Suppl: 203-9, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6109422

RESUMEN

The use of analgesic drugs is only one part of a multidisciplinary approach which offers also other possible palliative procedures for pain therapy. Pain complaints are placed against the background of terminal illness. The use of analgesic drugs and their combinations is discussed, with a short reference to their mechanism of action. The way of adminstration may have some impact on the efficacy of the analgesic regimen. Side effects and concomitant medication are reviewed.


Asunto(s)
Analgésicos/uso terapéutico , Neoplasias/complicaciones , Dolor/tratamiento farmacológico , Anfetaminas/uso terapéutico , Analgésicos/administración & dosificación , Analgésicos/efectos adversos , Analgésicos Opioides/uso terapéutico , Antidepresivos Tricíclicos/uso terapéutico , Antieméticos/uso terapéutico , Quimioterapia Combinada , Humanos , Dolor/etiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA