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1.
Nature ; 563(7733): E31, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30377312

RESUMEN

Change history: In this Letter, author M. Akhlaghi should be associated with affiliation (2) rather than (3). This error has been corrected online.

2.
Nature ; 562(7726): 229-232, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30275476

RESUMEN

Galaxies are surrounded by large reservoirs of gas, mostly hydrogen, that are fed by inflows from the intergalactic medium and by outflows from galactic winds. Absorption-line measurements along the lines of sight to bright and rare background quasars indicate that this circumgalactic medium extends far beyond the starlight seen in galaxies, but very little is known about its spatial distribution. The Lyman-α transition of atomic hydrogen at a wavelength of 121.6 nanometres is an important tracer of warm (about 104 kelvin) gas in and around galaxies, especially at cosmological redshifts greater than about 1.6 at which the spectral line becomes observable from the ground. Tracing cosmic hydrogen through its Lyman-α emission has been a long-standing goal of observational astrophysics1-3, but the extremely low surface brightness of the spatially extended emission is a formidable obstacle. A new window into circumgalactic environments was recently opened by the discovery of ubiquitous extended Lyman-α emission from hydrogen around high-redshift galaxies4,5. Such measurements were previously limited to especially favourable systems6-8 or to the use of massive statistical averaging9,10 because of the faintness of this emission. Here we report observations of low-surface-brightness Lyman-α emission surrounding faint galaxies at redshifts between 3 and 6. We find that the projected sky coverage approaches 100 per cent. The corresponding rate of incidence (the mean number of Lyman-α emitters penetrated by any arbitrary line of sight) is well above unity and similar to the incidence rate of high-column-density absorbers frequently detected in the spectra of distant quasars11-14. This similarity suggests that most circumgalactic atomic hydrogen at these redshifts has now been detected in emission.

3.
Thromb Haemost ; 85(1): 88-92, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11204594

RESUMEN

Vitamin K-dependent proteins play a critical role in hemostasis. We have analysed the genetic and environmental correlations between measures of several vitamin K-dependent proteins in 21 Spanish extended families, including 397 individuals. Plasma functional levels of factors II, VII, IX, X, protein C and functional protein S were assayed in an automated coagulometer. Antigenic levels of total and free protein S were measured using an ELISA method. A maximum likelihood-based covariance decomposition analysis was used to assess the heritability of each trait and the genetic and environmental correlations between all possible pairs. All of the plasma levels had a significant genetic component (heritability) ranging from 22% to 52% of the phenotypic variance. Among the 28 possible pairs of genetic correlations, 18 were significant at a level of p < 0.05 and six exhibited a p-value between 0.05 and 0.10. Positive environmental correlation was observed for 25 of the pairs (p < 0.05). We conclude that genetic effects account for a large proportion of the observed phenotypic variation in vitamin K-dependent proteins. Some of the genes appear to pleiotropically influence all of these traits, since most pairs of phenotypes exhibit significant genetic correlation. However, since these phenotypes show a high degree of environmental correlation, it is also likely that the same environmental factors influence them co-jointly.


Asunto(s)
Factores de Coagulación Sanguínea/metabolismo , Regulación de la Expresión Génica/genética , Hemostasis/genética , Vitamina K/farmacología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Factores de Coagulación Sanguínea/efectos de los fármacos , Factores de Coagulación Sanguínea/genética , Niño , Preescolar , Anticonceptivos Orales/sangre , Anticonceptivos Orales/farmacología , Factor X/genética , Factor X/metabolismo , Salud de la Familia , Femenino , Hemostasis/efectos de los fármacos , Hispánicos o Latinos/genética , Humanos , Lactante , Masculino , Persona de Mediana Edad , Fenotipo , Proteína S/genética , Proteína S/metabolismo , Factores Sexuales , Fumar/efectos adversos , Fumar/sangre
4.
Blood Coagul Fibrinolysis ; 6(7): 680-2, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8562841

RESUMEN

Acquired haemophilia is a rare disorder that it is associated with several diseases. Patients may present with spontaneous haematomas in different places which can sometimes be fatal. We present a 69-year-old woman with breast carcinoma who developed a factor VIII inhibitor. The initial haemorrhagic event was a spontaneous deep muscular haematoma in the right leg mimicking a deep venous thrombosis. She was successfully treated with prednisone.


Asunto(s)
Autoanticuerpos/sangre , Factor VIII/antagonistas & inhibidores , Hematoma/inmunología , Enfermedades Musculares/inmunología , Anciano , Neoplasias de la Mama/complicaciones , Diagnóstico Diferencial , Femenino , Hematoma/diagnóstico , Hematoma/tratamiento farmacológico , Humanos , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/tratamiento farmacológico , Prednisona/uso terapéutico , Tromboflebitis
5.
Phytopathology ; 90(11): 1246-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18944427

RESUMEN

ABSTRACT Fitness costs in Botrytis cinerea associated with dicarboximide resistance were studied. Spearman rank correlation coefficients were calculated between resistance to iprodione and survival ability both outside and inside the greenhouse, measured on isolates randomly chosen from a collection done in a survey of commercial greenhouses in Southeastern Spain in 1992. Survival was measured at 47, 83, and 110 days as percentage of surviving mycelia in a sample of artificially inoculated tomato stem pieces and as percentage of viable sclerotia from a sample of sclerotia produced on potato dextrose agar. Resistance to iprodione was measured by the fungicide concentration that reduces fungal growth by 50% (EC(50) values). Significant (P < 0.05) negative correlation coefficients between survival of sclerotia and resistance to iprodione were found for some samplings dates, which indicates that sclerotia of resistant isolates survive less well than sclerotia from sensitive isolates. For mycelia, no relationship between survival and resistance was found.

7.
Ann Hematol ; 77(1-2): 47-50, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9760152

RESUMEN

A case of type IV Ehlers-Danlos syndrome with a partial platelet delta-storage pool disease is reported. The diagnosis of Ehlers-Danlos was clinical. The platelet-dense granule deficiency was determined by ultrastructural platelet morphology. Dense bodies were decreased in number, and most showed loss or fragmentation of electron-dense material. Aggregation studies revealed a retarded response to ristocetin and arachidonic acid, which was corrected with desmopressin acetate-DDAVP.


Asunto(s)
Trastornos de las Plaquetas Sanguíneas/complicaciones , Síndrome de Ehlers-Danlos/complicaciones , Niño , Femenino , Humanos
8.
Sangre (Barc) ; 35(5): 375-9, 1990 Oct.
Artículo en Español | MEDLINE | ID: mdl-2291147

RESUMEN

The detection of TATC may inform about the presence of thrombin generation and, and hence of a pre-thrombotic status. An ELISA test (Enzygnst TAT) has been developed here in order to evaluate the predictive role played by TATC, and it was applied on 182 patients who distributed in 14 with cirrhosis of the liver, 11 with sepsis, 17 with chronic arterial insufficiency, 55 with neoplasms, 9 with thrombosis, 15 in postoperative period, 15 with pneumonia, 16 with disseminated intravascular coagulation (DIC), 14 with multiple injuries and 16 with pancreatitis. TATC levels were significantly increased in all groups with regard to the control group. Patients with thrombosis, sepsis, multiple injuries, DIC and in the postoperative period showed especially high TATC figures. No correlation between TATC and fibrinogen, platelet count, activated partial thromboplastin time or prothrombin complex assay was found in the post-operative patient-group. It was concluded that TATC are a good indicator of hypercoagulability.


Asunto(s)
Antitrombina III/análisis , Trastornos de la Coagulación Sanguínea/diagnóstico , Trombina/análisis , Adulto , Anciano , Antitrombina III/inmunología , Pruebas de Coagulación Sanguínea , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tromboembolia/prevención & control
9.
Neuroepidemiology ; 14(4): 155-64, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7643949

RESUMEN

We investigated the prevalence of dementing disorders in the city of Pamplona, Spain, using a door-to-door two-phase approach. We first administered the Cambridge Examination of Mental Disorders of the Elderly (CAMDEX) to all survivors, as of March 1, 1991, of a probability sample of the total population identified in 1989 (n = 1,127). Using specified diagnostic criteria, the study neurologists extensively investigated those subjects who screened positive on CAMDEX. We found 194 subjects affected by dementia, 119 had Alzheimer's disease; 51 vascular or mixed dementia, and 16 secondary dementia. The prevalence of both dementia and Alzheimer's disease increased steeply with advancing age and was consistently higher in women. The prevalence of combined vascular and mixed dementia increased less rapidly with age, and was generally higher in men. Alzheimer's disease was the most common type of dementia. Our prevalence figures for dementia and Alzheimer's disease are similar to those previously reported in Europe.


Asunto(s)
Enfermedad de Alzheimer/epidemiología , Demencia Vascular/epidemiología , Demencia/epidemiología , Factores de Edad , Anciano , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Prevalencia , Factores Sexuales , España/epidemiología
10.
Neurologia ; 13(3): 111-9, 1998 Mar.
Artículo en Español | MEDLINE | ID: mdl-9608217

RESUMEN

The Mini-Mental-State Examination (MMSE) is widely used as a screening tool for dementia in epidemiological studies. Its applicability in population-based studies is nevertheless limited by its low specificity. The effect of age and educational level have been usually ignored when cut-off scores have been selected. The aim of this study was to evaluate the effect of age and educational level on the MMSE scores in a representative sample of subjects older than 70 and provide adjusted normalised data according to these two variables, after excluding subjects with dementia or cognitive decline. Population-based, cross-sectional and longitudinal study of a representative cohort of 1367 subjects older than 70. All subjects with suspected dementia or cognitive decline received a neurological evaluation where clinical and etiological diagnosis were established. Normal MMSE scores, as defined by the 10th percentile, varied significantly across age and educational level groups. Exclusion of demented or cognitively declined patients from the reference population reduced the variability and "range of normality", but this remained excessively high in the older and less educated groups. The use of different cut-off points for each age and educational level groups may improve the specificity and applicability of the MMSE in population-based epidemiological studies. However, the wide amplitude of the range of normality suggests that different approaches, other than this vibariate analysis, may prove more adequate in the selection of cut-off scores for the MMSE.


Asunto(s)
Demencia/diagnóstico , Demencia/epidemiología , Pruebas Neuropsicológicas , Distribución por Edad , Anciano , Anciano de 80 o más Años , Escolaridad , Femenino , Humanos , Masculino , España/epidemiología
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