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1.
Nat Commun ; 8(1): 89, 2017 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-28743903

RESUMEN

Despite the international agreement to reduce global warming to below 2 °C, the Intended Nationally Determined Contributions submitted for the COP21 would lead to a global temperature rise of about 3 °C. The relative consequences of such a one-degree additional warming have not yet been investigated for regional air quality. Here we found that a + 3 °C global pollutant emission trajectory with respect to pre-industrial climate (reached along the 2040-2069 period under a RCP8.5 scenario) would significantly increase European ozone levels relative to a 2 °C one (reached along the 2028-2057 period under a RCP4.5 scenario). This increase is particularly high over industrial regions, large urban areas, and over Southern Europe and would annihilate the benefits of emission reduction policies. The regional ozone increase mainly stems from the advection of ozone at Europe's boundaries, themselves due to high global methane concentrations associated with the RCP8.5 emission scenario. These results make regional emission regulation, combined with emissions-reduction policies for global methane, of crucial importance.Current national pledges to reduce greenhouse gas emissions track to a temperature rise of about 3 °C. Here the authors use future projections to show that 3 °C warming under a business as usual scenario would result in large increases in ozone concentrations, off-setting any benefits from mitigation policies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/legislación & jurisprudencia , Contaminación del Aire/prevención & control , Calentamiento Global , Emisiones de Vehículos/análisis , Emisiones de Vehículos/legislación & jurisprudencia , Contaminantes Atmosféricos/metabolismo , Europa (Continente) , Calentamiento Global/legislación & jurisprudencia , Calentamiento Global/prevención & control , Calentamiento Global/estadística & datos numéricos , Ozono/análisis , Ozono/metabolismo , Temperatura , Emisiones de Vehículos/prevención & control
3.
J Synchrotron Radiat ; 18(Pt 2): 245-50, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21335912

RESUMEN

Synchrotron radiation time structure is becoming a common tool for studying dynamic properties of materials. The main limitation is often the wide time domain the user would like to access with pump-probe experiments. In order to perform photoelectron spectroscopy experiments over time scales from milliseconds to picoseconds it is mandatory to measure the time at which each measured photoelectron was created. For this reason the usual CCD camera-based two-dimensional detection of electron energy analyzers has been replaced by a new delay-line detector adapted to the time structure of the SOLEIL synchrotron radiation source. The new two-dimensional delay-line detector has a time resolution of 5 ns and was installed on a Scienta SES 2002 electron energy analyzer. The first application has been to characterize the time of flight of the photoemitted electrons as a function of their kinetic energy and the selected pass energy. By repeating the experiment as a function of the available pass energy and of the kinetic energy, a complete characterization of the analyzer behaviour in the time domain has been obtained. Even for kinetic energies as low as 10 eV at 2 eV pass energy, the time spread of the detected electrons is lower than 140 ns. These results and the time structure of the SOLEIL filling modes assure the possibility of performing pump-probe photoelectron spectroscopy experiments with the time resolution given by the SOLEIL pulse width, the best performance of the beamline and of the experimental station.

4.
Ann Fr Anesth Reanim ; 26(11): 973-9, 2007 Nov.
Artículo en Francés | MEDLINE | ID: mdl-17936565

RESUMEN

Delayed neurological deficit occurs among 30% of patients after aneurysmal subarachnoid haemorrhage, mainly related to cerebral vasospasm. The early detection of cerebral ischemia remains problematic. Conventional cerebral monitoring (as intracranial pressure and cerebral perfusion pressure) appears to be insufficient, because cerebral ischemia may occur without elevated intracranial pressure. Global cerebral monitoring as venous jugular oxygen saturation are useful for regional monitoring. Local monitoring as oxygen tissue partial pressure (PtiO2) and microdialysis are sensible for brain ischemia detection, but may also ignore episodes occurring in non-monitored brain area. For the detection of most episodes of brain ischemia, several monitoring system should be use performing a multimodal intracerebral monitoring. Brain microdialysis and oxygen tissue partial pressure are promising monitoring system.


Asunto(s)
Isquemia Encefálica/diagnóstico , Circulación Cerebrovascular/fisiología , Vasoespasmo Intracraneal/fisiopatología , Isquemia Encefálica/fisiopatología , Humanos , Presión Intracraneal , Venas Yugulares/fisiopatología , Monitoreo Fisiológico , Oxígeno/sangre , Presión Parcial , Tomografía Computarizada de Emisión de Fotón Único
5.
Clin Pharmacol Ther ; 81(3): 401-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17339870

RESUMEN

Intravenous (i.v.) paracetamol is used as 1-g infusions with a maximal daily dose of 4 g/day. However, a higher initial analgesic dose could be of interest in the immediate postoperative period when the pain is maximal. The purpose of the present study was to determine in healthy subjects the safety and the pharmacokinetics of i.v. paracetamol, starting with a 2-g dose, followed by 1-g doses every 6 h, leading to a total of 5 g the first 24 h. This was an open-label, single-sequence study. The paracetamol pharmacokinetic profile was assessed in 26 subjects after both the 2-g starting dose and the 1-g doses. Safety, especially hepatotoxicity, was evaluated up to 72 h after the initial 2-g dose. Following the first 15-min i.v. administration of paracetamol 2 g, plasma concentrations ranged from 67.9+/-21.8 mug/ml (peak plasma concentration (C(max)) at the end of infusion) to 6.2+/-2.3 mug/ml (trough plasma concentration (C(min)) measured just before the next infusion) without any C(max) in the toxic range for any subject. After the repeated 1-g infusions, the plasma concentrations were approximately 35% lower than that measured after 2 g, showing the absence of accumulation. No clinical adverse events related to the drug administration nor clinically relevant changes in laboratory parameters, including biochemical signs of hepatotoxicity, were reported. After i.v. administration of paracetamol 2-g starting dose and 5 g during the first 24 h, the pharmacokinetics of paracetamol remain unchanged, with concentrations far below the toxic threshold. Overall, these results demonstrate that the i.v. administration of a 2-g starting dose of paracetamol, followed by three i.v. administrations of 1 g during the first 24 h is safe in healthy subjects.


Asunto(s)
Acetaminofén/efectos adversos , Acetaminofén/farmacocinética , Analgésicos no Narcóticos/efectos adversos , Analgésicos no Narcóticos/farmacocinética , Acetaminofén/administración & dosificación , Adulto , Analgésicos no Narcóticos/administración & dosificación , Área Bajo la Curva , Recuento de Células Sanguíneas , Presión Sanguínea/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Electrocardiografía/efectos de los fármacos , Femenino , Semivida , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Infusiones Intravenosas , Pruebas de Función Hepática , Masculino , Espectrofotometría Ultravioleta
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 58(11): 2313-21, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12353681

RESUMEN

In order to study absorption line profiles using the stabilized diode laser spectrometer of Laboratoire de Physique Moléculaire et Applications (LPMA), a reliable determination of the emission line shape of different diodes laser is needed. In the near infrared region (1.39 and 1.66 microm) we used Distributed Feed Back diode lasers which operate around room temperature and in the middle infrared (5 and 8 microm) we used lead salt diode lasers cooled in a helium closed cycle cryostat or in a liquid nitrogen dewar. Some results obtained in H2O line profile studies in the 1.39 and 5 microm regions are presented as examples demonstrating how absorption line profile measurements can lead to erroneous values of the spectroscopic parameters when the contribution of the diode laser emission line width is neglected.


Asunto(s)
Espectrofotometría/instrumentación , Espectrofotometría/métodos , Agua/química
8.
Am J Ind Med ; 26(3): 349-58, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7977408

RESUMEN

The profiles of occupational asbestos exposure were investigated in a series of 66 hospital patients in whom pleural plaques constituted the only asbestos-induced abnormality. The relationship between a radiological semiquantitative score of pleural plaques and indices of asbestos exposure was also examined. On the basis of a standardized occupational questionnaire, four classes of asbestos exposure were distinguished in our study population: no evidence of exposure, low-level exposure, sporadic exposure at higher levels, and a remaining group of individuals with substantial exposure. Asbestos body count in bronchoalveolar lavage fluid (BALF) was used as an objective indicator of cumulative lung retention of asbestos. Our results support the data indicating that pleural plaques may occur in subjects with low-level or sporadic asbestos exposure. Although it is admitted that pleural plaques are strongly associated with past asbestos exposure, our data suggest that the stage of pleural plaques was not correlated to the level, frequency, duration of exposure nor to the amount of asbestos bodies in the BALF in subjects free of any lung parenchymal abnormalities on high resolution computerized tomography.


Asunto(s)
Amianto/análisis , Líquido del Lavado Bronquioalveolar/química , Exposición Profesional , Pleura/diagnóstico por imagen , Adulto , Anciano , Asbestosis/diagnóstico , Humanos , Persona de Mediana Edad , Radiografía , Encuestas y Cuestionarios
9.
Occup Environ Med ; 51(4): 244-9, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8199666

RESUMEN

Exposure to asbestos was evaluated in 131 patients with pleural malignant mesothelioma in the Paris area between 1986 and 1992 using data from a detailed specific questionnaire and light microscopy analysis of the retention of asbestos bodies in bronchoalveolar lavage fluid or lung tissue. Probable or definite exposure to significant levels of asbestos dust was identified in only 48 (36.6%) subjects, and significant asbestos body counts (above 1 asbestos body/ml in bronchoalveolar lavage fluid or 1000 asbestos bodies/g of dry lung tissue) were found in only 45 (34.3%) subjects. Overall 50 subjects had experienced exposure to only low levels of asbestos or no exposure at all and showed no significant retention of asbestos bodies in the biological sample analysed. Previous studies have shown that light microscopy may be useful in the identification of subjects with previous exposure to asbestos. In this study, apart from cases with obvious exposure to asbestos, a large group of subjects seemed to have a history of exposure or lung retention of asbestos bodies suggestive of very low levels of cumulative exposure, similar to those described in the general population.


Asunto(s)
Amianto/efectos adversos , Mesotelioma/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Neoplasias Pleurales/etiología , Adulto , Anciano , Anciano de 80 o más Años , Amianto/análisis , Líquido del Lavado Bronquioalveolar/química , Estudios de Casos y Controles , Polvo/efectos adversos , Femenino , Humanos , Industrias , Pulmón/química , Masculino , Persona de Mediana Edad , Paris , Factores de Tiempo
10.
J Otolaryngol ; 23(1): 67-8, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8170025

RESUMEN

Ectopic teeth are seldom found in the nose, although a few reports can be retrieved in the literature. Such a case is hereby presented and briefly discussed. This benign condition is certainly a curiosity.


Asunto(s)
Coristoma/patología , Enfermedades Nasales/patología , Diente Supernumerario , Adolescente , Humanos , Masculino
13.
IARC Sci Publ ; (90): 291-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2744828

RESUMEN

The widespread use of man-made mineral fibres (MMMF) as insulation products in buildings can be a potential source of indoor pollution, but few data are available. Pollution levels were determined at 79 indoor and 18 outdoor locations. The standardized method (membrane filter method) was adapted to the environmental settings: 10 m3 of air was sampled over a period of 5 days; the specimen was prepared by an indirect method (low-temperature ashing); counting was carried out at a magnification of 250; MMMF were identified by their optical properties under the polarizing optical microscope. Indoor pollution levels were found to be in the range 0-6230 respirable fibres per m3, with a median value of 3. Outdoor airborne pollution levels were lower than 15 respirable fibres per m3, with a median value of 1. More data are needed in order to make a more precise assessment of the risk associated with environmental MMMF pollution; a standardized method of obtaining such data is also necessary.


Asunto(s)
Contaminantes Atmosféricos/análisis , Materiales de Construcción , Arquitectura y Construcción de Instituciones de Salud , Sustancias Peligrosas/análisis , Minerales/análisis , Amianto/análisis
14.
IARC Sci Publ ; (90): 406-10, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2545614

RESUMEN

In north-east Corsica, asbestos outcrops are a source of environmental pollution, as assessed by airborne concentrations of chrysotile and tremolite that are significantly higher in the north-east than the north-west. For this reason we compared the frequencies of patients with asbestos pleural plaques in these 2 regions by checking the X-rays of 1721 patients born in north Corsica who had not undergone any occupational exposure to asbestos. The percentage of plaques was respectively 3.7% in the north-east, and 1.1% in the north-west (p less than 0.05). The relative risk of 3.3 demonstrates a strong relationship between environmental asbestos and the pleural plaques found in north-east Corsica.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Asbestos Anfíboles , Amianto/efectos adversos , Enfermedades Pleurales/diagnóstico por imagen , Ácido Silícico/efectos adversos , Dióxido de Silicio/efectos adversos , Anciano , Contaminantes Atmosféricos/análisis , Amianto/análisis , Asbestos Serpentinas , Femenino , Francia , Humanos , Masculino , Enfermedades Pleurales/etiología , Radiografía , Ácido Silícico/análisis
16.
Phys Rev D Part Fields ; 35(12): 3944-3954, 1987 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9957657
17.
Rev Mal Respir ; 4(1): 23-7, 1987.
Artículo en Francés | MEDLINE | ID: mdl-3589103

RESUMEN

As opposed to North-West Corsica, North-East Corsica is rich in asbestos outcrops and a source of environmental pollution as can be seen in the airborne concentration of chrysotile and above all tremolite. We have composed the frequency of asbestos pleural plaques occurring in subjects in the two regions starting with a retrospective analysis of the radiological records of 1,721 patients born in Northern Corsica and having no occupational exposure to asbestos. The frequency is 3.8% in the North-East and 1.1% in the North-West (p less than 5%). The relative East-West risk, which is 3.3%, shows the existence of a link between pleural plaques and environmental exposure to asbestos in North-East Corsica.


Asunto(s)
Asbestosis/diagnóstico por imagen , Enfermedades Pleurales/diagnóstico por imagen , Anciano , Contaminantes Atmosféricos/efectos adversos , Asbestosis/epidemiología , Asbestosis/etiología , Exposición a Riesgos Ambientales , Femenino , Francia , Humanos , Masculino , Enfermedades Pleurales/etiología , Radiografía , Estudios Retrospectivos
18.
Arch Virol ; 92(3-4): 261-71, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3028333

RESUMEN

We studied the minimal infective dose of the gastroenteritis virus, rotavirus. Increasingly lower doses [10(4), 10(3), 10(1), 1, 10(-2) plaque forming units (PFU)] of the OSU strain of porcine rotavirus were administered to highly susceptible (colostrum deprived, cesarean derived) newborn miniature swine piglets. In vitro studies showed that virus infectivity was inactivated in piglet gastric juice, both by low pH and by pH- and concentration-dependent factor(s). These factors remain unidentified, but to prevent intragastric viral inactivation, sodium bicarbonate was administered prior to oral virus inoculation of piglets with virulent (non-tissue culture passaged) virus. The lowest dose of virus to induce clinical illness or to demonstrate viral replication by recovery of significantly more infectious virus than was administered, or both, was 1 PFU. These results should help establish standards for virus contamination of water and recommendations for evaluating disinfection procedures for rotaviruses.


Asunto(s)
Infecciones por Rotavirus/microbiología , Rotavirus/patogenicidad , Animales , Jugo Gástrico/fisiología , Concentración de Iones de Hidrógeno , Rotavirus/fisiología , Infecciones por Rotavirus/transmisión , Porcinos , Porcinos Enanos , Replicación Viral
20.
J Comput Tomogr ; 8(2): 125-8, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6713924

RESUMEN

An atypical pattern of pericardial cyst was observed on a routine chest radiograph of a healthy 25-year-old woman. It appeared as an important elevation of the right diaphragm. The cystic nature of the mass was easily disclosed by ultrasonography and computed tomography, but its location--thoracic, diaphragmatic, or subphrenic--remained questionable. Finally, a percutaneous puncture yielded 1300 mL of clear liquid. Despite this huge volume, the cyst had been asymptomatic and did not recur after complete aspiration. Retrospectively, owing to previous files, we could recognize the evolution of a pericardial cyst from the age of 13 years. At that time, it was much smaller and was evaluated by a series of aggressive investigations, although it had a more typical pattern and was confined to the right cardiophrenic angle.


Asunto(s)
Quiste Mediastínico/diagnóstico por imagen , Adulto , Drenaje , Femenino , Estudios de Seguimiento , Humanos , Quiste Mediastínico/diagnóstico , Quiste Mediastínico/terapia , Punciones , Factores de Tiempo , Tomografía Computarizada por Rayos X , Ultrasonografía
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