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1.
Hum Reprod ; 39(2): 346-354, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38142239

RESUMO

STUDY QUESTION: Do severe endometriosis-related painful symptoms impact ART live birth rates? SUMMARY ANSWER: Severe pain symptoms are not associated with reduced ART live birth rates in endometriosis patients. WHAT IS KNOWN ALREADY: ART is currently recognized as one of the main therapeutic options to manage endometriosis-related infertility. Presently, no data exist in the literature regarding the association between the core symptom of the disease, e.g. pain and ART reproductive outcomes. STUDY DESIGN, SIZE, DURATION: Observational cohort study of 354 endometriosis patients, who underwent ART at a tertiary care university hospital, between October 2014 and October 2021. Diagnosis of endometriosis was based on published imaging criteria using transvaginal sonography and magnetic resonance imaging, and histologically confirmed in women who had a previous history of endometriosis surgery (n = 127, 35.9%). PARTICIPANTS/MATERIALS, SETTING, METHODS: The intensity of painful symptoms related to dysmenorrhea (DM), dyspareunia (DP), noncyclic chronic pelvic pain, gastrointestinal (GI) pain, or lower urinary tract pain was evaluated using a 10-point visual analog scale (VAS), before ART. Severe pain was defined as having a VAS of 7 or higher for at least one symptom. The main outcome measure was the cumulative live birth rate (CLBR) per patient. We analyzed the impact of endometriosis-related painful symptoms on ART live births using univariable and multivariate analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Three hundred and fifty-four endometriosis patients underwent 711 ART cycles. The mean age of the population was 33.8 ± 3.7 years, and the mean duration of infertility was 3.6 ± 2.1 years. The distribution of the endometriosis phenotypes was 3.1% superficial endometriosis, 8.2% ovarian endometrioma, and 88.7% deep infiltrating endometriosis. The mean VAS scores for DM, DP, and GI pain symptoms were 6.6 ± 2.7, 3.4 ± 3.1, and 3.1 ± 3.6, respectively. Two hundred and forty-two patients (68.4%) had severe pain symptoms. The CLBR per patient was 63.8% (226/354). Neither the mean VAS scores for the various painful symptoms nor the proportion of patients displaying severe pain differed significantly between patients who had a live birth and those who had not, based on univariate and multivariate analyses (P = 0.229). The only significant factors associated with negative ART live births were age >35 years (P < 0.001) and anti-Müllerian hormone levels <1.2 ng/ml (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: The diagnosis of endometriosis was based on imaging rather than surgery. This limitation is, however, inherent to the design of most studies on endometriosis patients reverting to ART first. WIDER IMPLICATIONS OF THE FINDINGS: Rather than considering a single argument such as pain, the decision-making process for choosing between ART and surgery in infertile endometriosis patients should be based on a multitude of aspects, including the patient's choice, the associated infertility factors, the endometriosis phenotypes, and the efficiency of medical therapies in regard to pain symptoms, through an individualized approach guided by a multidisciplinary team of experts. STUDY FUNDING/COMPETING INTEREST(S): No funding; no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Endometriose , Infertilidade , Gravidez , Humanos , Feminino , Adulto , Endometriose/complicações , Endometriose/cirurgia , Técnicas de Reprodução Assistida , Infertilidade/complicações , Nascido Vivo/epidemiologia , Dor Pélvica/complicações , Dismenorreia/etiologia , Estudos Retrospectivos
2.
Appl Radiat Isot ; 158: 109068, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32174369

RESUMO

Spectral unmixing was investigated for fast spectroscopic identification in γ-emitter mixtures at low-statistics in the case of measurements performed to prevent illegal nuclear material trafficking or for in situ environmental analysis following a radiological or nuclear accident. For that purpose, a multiplicative update algorithm based on full-spectrum analysis was tested in the case of a 3″x3″ NaI(Tl) detector. Automatic decision-making was addressed using Monte Carlo calculations of decision thresholds and detection limits. The first results obtained with a portable instrument equipped with a 3″x3″ NaI(Tl) detector designed for the control of food samples by non-expert users following a radiological or nuclear accident, are also presented.

3.
Appl Radiat Isot ; 155: 108921, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31629294

RESUMO

An internal consistency test of the calculation of coincidence-summing correction factors FC for volume sources is presented. The test is based on exact equations relating the values of FC calculated for three ideal measurement configurations. The test is applied to a number of 33 sets of FC values sent by 21 teams. Most sets passed the test, but not the results obtained using the quasi-point source approximation; in the latter case the test qualitatively indicated the magnitude of the bias of FC.

4.
Appl Radiat Isot ; 134: 13-17, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29113709

RESUMO

Two main non-destructive techniques can be used to measure standard 222Rn gas ampoules: well-type ionization chambers and gamma-ray spectrometry, the former being used in the Système International de Référence (SIR) for international comparison purposes. The reliability of these techniques requires that the variability of the flame-sealed gas glass ampoules used have a negligible influence on the detector response. This variability is studied in this work by considering three parameters: the volume of the ampoule, the position of the sealing point and the thickness of the glass. Results showed that variability of the gas ampoules induced measurement bias larger than the uncertainty of the standard sources.

5.
Appl Radiat Isot ; 109: 231-235, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26651176

RESUMO

The present paper addresses the calibration of well-type ionization chambers (ICs) used at LNE-LNHB as standard transfer instruments to calibrate hospitals in the case of SIR-Spheres(®)(90)Y resin microspheres (Sirtex, Australia). Developed for interventional oncology, this radiopharmaceutical is directly injected in the liver for cancer treatment via a selective internal radiation therapy. The present work was carried out in the framework of the European project "Metrology for molecular radiotherapy" (MetroMRT). As commonly performed in radionuclide metrology for radiopharmaceuticals, the objective is to ensure the metrological traceability of SIR-Spheres(®) to hospitals. Preceding studies were focused on primary measurements of SIR-Spheres(®) based on the TDCR (Triple to Double Coincidence Ratio) method, applied after the dissolution of the (90)Y-labeled resin microspheres. As (90)Y is a high-energy ß(-)-emitter, the IC response strongly depends on the transport of electrons in the radioactive solution and surroundings (vial, chamber liners and materials). The variability of the IC-response due to the geometry dependence is investigated by means of measurements and Monte Carlo simulations in the case of a Vinten IC. The aim of the present study was also to propose a reliable uncertainty for ICs calibrations for the standard transfer of SIR-Spheres(®) to hospitals.

6.
Appl Radiat Isot ; 97: 170-176, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25579458

RESUMO

The project "Metrology for molecular radiotherapy" is a collaborative European project initiated to bring together expertize in ionizing radiation metrology and nuclear medicine research. This project deals with the development of personalized dosimetry to individual patients who are undergoing molecular radiotherapy (also known as targeted radionuclide therapy). The general aim is to provide a metrological traceability to primary standards for individual dosimetry in the case of molecular radiotherapy. In particular, one objective is the standardization of (90)Y-labeled resin microspheres SIR-Spheres (Sirtex, Sydney, Australia) used for the treatment of liver cancer by radioembolization. The present paper describes the primary measurements carried out using the Triple to Double Coincidence Ratio (TDCR) method applied after the complete dissolution of the SIR-Spheres in the Sirtex vial. A method for the dissolution was developed to optimize the homogeneity of the solution to enable the primary measurements based on Cherenkov and liquid scintillation counting. A comprehensive description of the protocol implemented for the microsphere dissolution is reported. First calibration factors obtained with the reference ionization chambers at LNE-LNHB are also given.

7.
Appl Radiat Isot ; 95: 13-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25464171

RESUMO

In the framework of the organization of proficiency testing, filters with deposits of 137Cs and 90Sr+90Y radioactive aerosols have been submitted to laboratories for radionuclide measurement. Procedures for the special preparation and characterization of filters have been developed. The different steps of filter preparation, determination of the deposited radionuclide activity and characterization of the homogeneity of these deposits are presented. This method of filter preparation can also be used in the production of secondary standards, whose properties are more adapted to the needs of laboratories measuring radioactivity in filters than are the solid sources that they typically use.

8.
Appl Radiat Isot ; 87: 456-60, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24331857

RESUMO

Measurement of radionuclides from environmental samples includes a wide variety of matrix compositions and densities. To improve the traceability of environmental monitoring, LNE-LNHB intends to produce mixed γ-ray reference materials with a known mass activity and a composition as representative as possible of real environmental samples. This paper describes the preparation and characterization of a low density treated grass matrix spiked with mixed γ-emitters. This material was used in a proficiency test exercise whose results are presented.


Assuntos
Poaceae/química , Monitoramento de Radiação/métodos , Poluentes Radioativos/análise , Poluentes Radioativos/normas , Padrões de Referência
9.
Appl Radiat Isot ; 87: 101-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24369893

RESUMO

This study focuses on two radioisotopes of silver, (108m)Ag and (110m)Ag, characterized by a complex decay scheme. Each isotope has two disintegration modes, the isomeric transition leading to the daughter isotope ((108)Ag and (110)Ag, respectively) with a short half-life. The radioactive solution was obtained by neutron activation on silver powder enriched in (109)Ag. Gamma-spectrometry was carried out using a calibrated high purity germanium detector. The main relative photon emission intensities for both radionuclides were obtained and compared with previously published values.

10.
Appl Radiat Isot ; 70(9): 2112-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22445105

RESUMO

The second part of an intercomparison of the coincidence summing correction methods is presented. This exercise concerned three volume sources, filled with liquid radioactive solution. The same experimental spectra, decay scheme and photon emission intensities were used by all the participants. The results were expressed as coincidence summing corrective factors for several energies of (152)Eu and (134)Cs, and different source-to-detector distances. They are presented and discussed.


Assuntos
Algoritmos , Artefatos , Radioisótopos/análise , Radioisótopos/normas , Radiometria/métodos , Radiometria/normas , Espectrometria gama/métodos , Meia-Vida , Internacionalidade , Doses de Radiação , Radioisótopos/química , Padrões de Referência , Valores de Referência
11.
Appl Radiat Isot ; 70(9): 1843-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22445712

RESUMO

Radioactivity found in wild food products has assumed greater importance when assessing the total exposure of the population. For this reason, IRMM has been developing a reference material for the activity concentration of three radionuclides in bilberry samples. In order to characterise this new material, a CCRI(II) supplementary comparison was organised. The difficulties encountered in this comparison are discussed, in particular the efficiency calibration for volume sources of gamma-ray emitters, and comparison reference values for (137)Cs and (40)K are calculated.


Assuntos
Análise de Alimentos/normas , Contaminação Radioativa de Alimentos/análise , Frutas/química , Radioisótopos/análise , Radioisótopos/química , Radiometria/normas , Vaccinium myrtillus/química , Internacionalidade , Doses de Radiação , Padrões de Referência , Valores de Referência
12.
J Environ Radioact ; 101(9): 780-3, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20537447

RESUMO

In this work, the activities of radionuclides in a marine sediment sample have been determined. The gamma spectrometer comprises an N type coaxial HPGe detector with active shielding to reduce cosmic background. The mass activities of radionuclides have been derived and found to be around a few Bq kg(-1) to several hundreds Bq kg(-1) with relative uncertainties in this paper quoted corresponding to the combined standard uncertainties (k=1).


Assuntos
Sedimentos Geológicos/química , Monitoramento de Radiação , Radioisótopos/análise , Espectrometria gama/métodos , Poluentes Radioativos da Água/análise , Radioisótopos/química , Água do Mar/química , Poluentes Radioativos da Água/química
13.
Appl Radiat Isot ; 68(7-8): 1571-7; discussion 1577, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20116267

RESUMO

To study the decay scheme of (126)Sn, two samples of a purified solution were measured by gamma-ray spectrometry and the relative photon emission intensities were determined. The (126)Sb(m) isomeric branching ratio was derived to be 18.6 (6) %. The maximum beta energy of the (126)Sn decay was checked by liquid scintillation. The Kbeta/Kalpha intensity ratio of Sb was determined being 0.226 (11). These new experimental results were used to re-examine the whole decay scheme of (126)Sn and its daughters.

14.
Appl Radiat Isot ; 68(7-8): 1407-12; discussion 1412, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20117939

RESUMO

A comparison of the coincidence summing correction methods is presented. Since there are several ways for computing these corrections, each method has advantages and drawbacks that could be compared. This part of the comparison was restricted to point sources. The same experimental spectra, decay scheme and photon emission intensities were used by all the participants. The results were expressed as coincidence summing correction factors for several energies of (152)Eu and (134)Cs, and three source-to-detector distances. They are presented and discussed.

15.
Appl Radiat Isot ; 66(6-7): 715-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18394911

RESUMO

Measurements of (241)Am L X-ray emission probabilities were conducted using both HPGe and Si(Li) detectors. The efficiency calibrations of these detectors were performed by means of a tunable, monochromatic photon beam and the determination of the thickness of absorbing materials inside the detector. These efficiency calibrations were obtained without any reference to radionuclide decay data, and with 0.8% relative standard uncertainty. The complex L X-ray region was processed using Voigt functions and by taking account of the detector response function established with the monochromatic beam. Twenty-two components of the L X-ray group were identified and quantified. The present results are compared with previously published data.

16.
Health Phys ; 70(1): 36-40, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7499149

RESUMO

The Moyer model, based on a semi-empirical method validated in the 7.4 to 350 GeV energy range, is generally used to calculate lateral shielding for high energy proton accelerators. Measurements made for the Saclay Synchrocyclotron, Saturne, have enabled the parameters corresponding to a 2.7 GeV model to be studied for different target thicknesses and angles of observation. These studies show how new data have been used to modify the equations of the model.


Assuntos
Aceleradores de Partículas , Prótons , Doses de Radiação , Proteção Radiológica
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