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1.
Radiat Prot Dosimetry ; 177(1-2): 57-62, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29140505

RESUMEN

During years 2010-12 an automated, on-line and wireless outdoor measurement station of atmospheric radon, gamma dose rate and meteorological parameters was realised at the National Radiation Protection Institute (NRPI) in Prague. At the turn of the year 2013 an expansion of the existing station was completed. Under the project funded by the Czech Technological Agency a new updated station was established, additionally equipped with modules for measurement of atmospheric radon/thoron short-lived decay products, radon in water and soil and radon exhalation rate from soil. After the introduction of the station updated key detection parameters and benefits, its use for atmospheric modelling and monitoring is demonstrated. There are summarised results from the 3-year measurement period in the NRPI outdoor area in Prague and from simultaneous annual measurement performed by another similar station located near uranium mud fields in DIAMO, state enterprise, Stráz pod Ralskem. Observed seasonal and diurnal variations of atmospheric radon concentrations and variability of the equilibrium factor, F, are illustrated and compared.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Monitoreo de Radiación/métodos , Hijas del Radón/análisis , Radón/análisis , Contaminantes Radiactivos del Suelo/análisis , República Checa , Rayos gamma , Tiempo (Meteorología)
2.
Radiat Prot Dosimetry ; 160(1-3): 57-61, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24743758

RESUMEN

In autumn 2010, an outdoor measuring station for measurement of atmospheric radon, gamma equivalent dose rate in the range of 100 nSv h(-1)-1 Sv h(-1) and proper meteorological parameters such as thermal air gradient, relative air humidity, wind speed and direction and solar radiation intensity was built in the area of the National Radiation Protection Institute vvi. The station was designed to be independent of an electrical network and enables on-line wireless transfer of all data. After introduction of the station, illustrations of its measurement properties and the results of measured diurnal and seasonal variability of atmospheric radon, based on annual continuous measurement using a high-volume scintillation cell at a height of 2.5 m above the ground, are presented.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos/análisis , Radón/análisis , Estaciones del Año , Movimientos del Aire , República Checa , Humanos , Medición de Riesgo , Temperatura , Factores de Tiempo , Viento
3.
Radiat Prot Dosimetry ; 153(3): 334-41, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22740647

RESUMEN

In this paper, repeated measurements of radon progeny concentration in dwellings in the Czech Republic are described. Two distinct data sets are available: one based on present measurements in 170 selected dwellings in the Central Bohemian Pluton with a primary measurement carried out in the 1990s and the other based on 1920 annual measurements in 960 single-family houses in the Czech Republic in 1992 and repeatedly in 1993. The analysis of variance model with random effects is applied to data to evaluate the variability of measurements. The calculated variability attributable to repeated measurements is compared with results from other countries. In epidemiological studies, ignoring the variability of measurements may lead to biased estimates of risk of lung cancer.


Asunto(s)
Contaminación del Aire Interior/análisis , Contaminación Radiactiva del Aire/análisis , Vivienda , Neoplasias Pulmonares/etiología , Hijas del Radón , Radón/análisis , Calibración , República Checa , Humanos , Neoplasias Pulmonares/epidemiología , Modelos Estadísticos , Control de Calidad , Monitoreo de Radiación , Reproducibilidad de los Resultados , Estaciones del Año , Factores de Tiempo
4.
Reprod Domest Anim ; 44(3): 480-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18992089

RESUMEN

Joining immature gamete cryopreservation and germinal vesicle transplantation (GVT) technique could greatly improve assisted reproductive technologies in animal breeding and human medicine. The present work was aimed to assess the most suitable cryopreservation protocol between slow freezing and vitrification for immature denuded bovine oocytes, able to preserve both nuclear and cytoplasmic competence after thawing. In addition, the outcome of germinal vesicle transfer procedure and gamete reconstruction was tested on the most effective cryopreservation system. Oocytes, isolated from slaughterhouse ovaries, were stored after cumulus cells removal either by slow freezing or by vitrification in open pulled straws. After thawing, oocytes were matured for 24 h in co-culture with an equal number of just isolated intact cumulus enclosed oocytes, and fixed in order to evaluate the stage of meiotic progression and cytoskeleton organization. Our results showed that after warming, vitrified oocytes reached metaphase II (MII) in a percentage significantly higher than oocytes cryopreserved by slow freezing (76.2% and 36.5% respectively, p < 0.05). Moreover, vitrification process preserved the organization of cytoskeleton elements in a higher proportion of oocytes than slow freezing procedure. Therefore vitrification has been identified as the elective method for denuded immature oocytes banking and it has been applied in the second part of the study. Our results showed that 38.3% of oocytes reconstructed from vitrified gametes reached the MII of meiotic division, with efficiency not different from oocytes reconstructed with fresh gametes. We conclude that vitrification represents a suitable method of GV stage denuded oocyte banking since both nuclear and cytoplasmic components derived from cryopreserved immature oocytes can be utilized for GVT.


Asunto(s)
Bovinos , Criopreservación/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Oocitos/fisiología , Animales , Núcleo Celular/fisiología , Criopreservación/métodos , Células del Cúmulo/fisiología , Citoplasma/fisiología , Citoesqueleto/ultraestructura , Femenino , Calor , Meiosis , Metafase , Oocitos/ultraestructura
5.
Zygote ; 15(4): 307-15, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17967210

RESUMEN

The aim of our study was to examine whether: (1) the exposure of bovine embryos to the BHV-1 virus in vitro can compromise their further development and alter the ultrastructural morphology of cellular organelles; (2) whether the zona pellucida (ZP) can be a barrier protecting embryos against infection; and (3) whether washing with trypsin after viral exposure can prevent virus penetration inside the embryo and subsequent virus-induced damages. The embryos were recovered from superovulated Holstein-Friesian donor cows on day 6 of the estrous cycle. Only compact morulas or early blastocysts were selected for experiments with virus incubation. We used the embryos either with intact ZP (either with or without trypsin washing) or embryos in which the ZP barrier was avoided by using the microinjection of a BHV-1 suspension under the ZP. ZP-intact embryos (n = 153) were exposed to BHV-1 at 10(6.16) TCID(50)/ml for 60 min, then washed in trypsin according to IETS guidelines and postincubated in synthetic oviduct fluid (SOF) medium for 48 h. Some of the embryos (n = 36) were microinjected with 20 pl of BHV-1 suspension under the ZP, the embryos were washed in SOF medium and cultured for 48 h. Embryo development was evaluated by morphological inspection, the presence of viral particles was determined both immunocytochemically, using fluorescent anti-IBR-FITC conjugate and by transmission electron microscopy (TEM) on the basis of the ultrastructure of the cellular organelles. It was found that BHV-1 exposure impairs embryo development to higher preimplantation stages independent of the presence of the ZP or the trypsin treatment step, as most of the embryos were arrested at the morula stage when compared with the control. Immunofluorescence analysis confirmed the presence of BHV-1 particles in about 75% of embryos that were passed through the trypsin treatment and in all the BHV-1-microinjected embryos. Ultrastructural analysis, using TEM, revealed the presence of virus-like particles inside the BHV-1-exposed embryos, where the trypsin washing step was omitted. Conversely, in trypsin-treated BHV-1-exposed embryos, TEM detected only the envelope-free virus-like particles adhered to pores of the ZP. The embryos that were microinjected with BHV-1 suspension showed the presence of BHV-1 particles, as well as ultrastructural alterations in cell organelles. Taken together these findings may suggest that BHV-1 infection compromises preimplantation development of bovine embryos in vitro and therefore the ZP may not be enough on its own to prevent virus-induced damage, unless it is not accompanied with trypsin washing.


Asunto(s)
Blastocisto/virología , Desarrollo Embrionario/fisiología , Herpesvirus Bovino 1/patogenicidad , Animales , Blastocisto/ultraestructura , Bovinos , Femenino , Inmunohistoquímica , Técnicas In Vitro , Microscopía Electrónica de Transmisión , Embarazo , Tripsina , Zona Pelúcida/fisiología , Zona Pelúcida/virología
6.
Cesk Farm ; 41(4-5): 162-5, 1992 Jul.
Artículo en Eslovaco | MEDLINE | ID: mdl-1451195

RESUMEN

The present paper aims at an analysis of the consumption of antibiotics in relation to age, sex and diagnosis in the district of Bratislava-vidiek. The prescription of 17 primary out-patient care physicians was evaluated. The set under study included 17,771 inhabitants divided into 10 age categories. Drug consumption was expressed by the number of packages per 1000 inhabitants and a month. The processed data were statistically evaluated. The results of the paper showed a higher consumption in women. Within the framework of the age categories under study, the consumption of antibiotics does not increase with age. The highest consumption of antibiotics, 70.45%, was found in the diseases of the respiratory system, the consumption in acute diseases being 60.46%. Tetracycline and penicillin antibiotics are the most frequently used preparations in the population under study.


Asunto(s)
Antibacterianos , Adolescente , Adulto , Factores de Edad , Checoslovaquia , Utilización de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales
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