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991.
Dino Numerato Giovanni Fattore Fabrizio Tediosi Rinaldo Zanini Mikko Peltola Helen Banks Péter Mihalicza Liisa Lehtonen Sofia Sveréus Richard Heijink S?ren Toksvig Klitkou Eilidh Fletcher Amber van der Heijden Fredrik Lundberg Eelco Over Unto H?kkinen Timo T. Sepp?l? 《PloS one》2015,10(6)
The objective of this paper was to compare health outcomes and hospital care use of very low birth weight (VLBW), and very preterm (VLGA) infants in seven European countries. Analysis was performed on linkable patient-level registry data from seven European countries between 2006 and 2008 (Finland, Hungary, Italy (the Province of Rome), the Netherlands, Norway, Scotland, and Sweden). Mortality and length of stay (LoS) were adjusted for differences in gestational age (GA), sex, intrauterine growth, Apgar score at five minutes, parity and multiple births. The analysis included 16,087 infants. Both the 30-day and one-year adjusted mortality rates were lowest in the Nordic countries (Finland, Sweden and Norway) and Scotland and highest in Hungary and the Netherlands. For survivors, the adjusted average LoS during the first year of life ranged from 56 days in the Netherlands and Scotland to 81 days in Hungary. There were large differences between European countries in mortality rates and LoS in VLBW and VLGA infants. Substantial data linkage problems were observed in most countries due to inadequate identification procedures at birth, which limit data validity and should be addressed by policy makers across Europe. 相似文献
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Metabolic rates are one of many measures that are used to explain species' response to environmental change. Static respirometry is used to calculate the standard metabolic rate (SMR) of fish, and when combined with exhaustive chase protocols it can be used to measure maximum metabolic rate (MMR) and aerobic scope (AS) as well. While these methods have been tested in comparison to swim tunnels and chambers with circular currents, they have not been tested in comparison with a no-chase control. We used a repeated-measures design to compare estimates of SMR, MMR and AS in European perch Perca fluviatilis following three protocols: (a) a no-chase control; (b) a 3-min exhaustive chase; and (c) a 3-min exhaustive chase followed by 1-min air exposure. We found that, contrary to expectations, exhaustive chase protocols underestimate MMR and AS at 18°C, compared to the no-chase control. This suggests that metabolic rates of other species with similar locomotorty modes or lifestyles could be similarly underestimated using chase protocols. These underestimates have implications for studies examining metabolic performance and responses to climate change scenarios. To prevent underestimates, future experiments measuring metabolic rates should include a pilot with a no-chase control or, when appropriate, an adjusted methodology in which trials end with the exhaustive chase instead of beginning with it. 相似文献
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Thoren FB Aurelius J Martner A 《Nature medicine》2011,17(5):537; author reply 537-537; author reply 538
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Fagerberg L Strömberg S El-Obeid A Gry M Nilsson K Uhlen M Ponten F Asplund A 《Journal of proteome research》2011,10(9):4066-4075
Human cancer cell lines grown in vitro are frequently used to decipher basic cell biological phenomena and to also specifically study different forms of cancer. Here we present the first large-scale study of protein expression patterns in cell lines using an antibody-based proteomics approach. We analyzed the expression pattern of 5436 proteins in 45 different cell lines using hierarchical clustering, principal component analysis, and two-group comparisons for the identification of differentially expressed proteins. Our results show that immunohistochemically determined protein profiles can categorize cell lines into groups that overall reflect the tumor tissue of origin and that hematological cell lines appear to retain their protein profiles to a higher degree than cell lines established from solid tumors. The two-group comparisons reveal well-characterized proteins as well as previously unstudied proteins that could be of potential interest for further investigations. Moreover, multiple myeloma cells and cells of myeloid origin were found to share a protein profile, relative to the protein profile of lymphoid leukemia and lymphoma cells, possibly reflecting their common dependency of bone marrow microenvironment. This work also provides an extensive list of antibodies, for which high-resolution images as well as validation data are available on the Human Protein Atlas ( www.proteinatlas.org ), that are of potential use in cell line studies. 相似文献
999.
Stereo "3D" depth perception requires the visual system to extract binocular disparities between the two eyes' images. Several current models of this process, based on the known physiology of primary visual cortex (V1), do this by computing a piecewise-frontoparallel local cross-correlation between the left and right eye's images. The size of the "window" within which detectors examine the local cross-correlation corresponds to the receptive field size of V1 neurons. This basic model has successfully captured many aspects of human depth perception. In particular, it accounts for the low human stereoresolution for sinusoidal depth corrugations, suggesting that the limit on stereoresolution may be set in primary visual cortex. An important feature of the model, reflecting a key property of V1 neurons, is that the initial disparity encoding is performed by detectors tuned to locally uniform patches of disparity. Such detectors respond better to square-wave depth corrugations, since these are locally flat, than to sinusoidal corrugations which are slanted almost everywhere. Consequently, for any given window size, current models predict better performance for square-wave disparity corrugations than for sine-wave corrugations at high amplitudes. We have recently shown that this prediction is not borne out: humans perform no better with square-wave than with sine-wave corrugations, even at high amplitudes. The failure of this prediction raised the question of whether stereoresolution may actually be set at later stages of cortical processing, perhaps involving neurons tuned to disparity slant or curvature. Here we extend the local cross-correlation model to include existing physiological and psychophysical evidence indicating that larger disparities are detected by neurons with larger receptive fields (a size/disparity correlation). We show that this simple modification succeeds in reconciling the model with human results, confirming that stereoresolution for disparity gratings may indeed be limited by the size of receptive fields in primary visual cortex. 相似文献
1000.
Sletta H Klinkenberg G Winnberg A Kvitvang HF Nilsen MB Krokan HE Otterlei M Bruheim P 《Journal of microbiological methods》2011,87(3):363-367
A high resolution high throughput screening method has been developed for stress response phenotyping of the global Saccharomyces cerevisiae knock out mutant collection. Stress causing agent is added at three concentrations to individual mutant cultures growing in early exponentially phase in 384-well microplates, and the dynamic effect of stress agent exposure is measured by following subsequent growth profiles of individual mutants with a resolution of three optical density measurements per hour. Software was written for calculation of sensitivity coefficients and efficient visual inspection of the growth and inhibition curves. Three DNA damage response causing agents were chosen to explore the feasibility of the new screening method: methyl methanesulphonate, 5-fluorouracil and cisplatin. They were tested in three biological replicas on a 1400 mutant large sub-library of the homozygote diploid S. cerevisiae gene knock out collection. The sub-library consisted of only mutants with a human ortholog to the inactivated gene. Almost 400 mutants were found more sensitive to one or more of the agents. Forty-nine mutants were sensitive to all three agents. One of the mutants, ERK5, sensitive to all three agents was chosen for follow-up human cell experiments to verify that such yeast screens can be used as hypothesis generator for human cell studies. Similar to yeast, HeLa cells became more sensitive against all three DNA damaging agents when co-treated with the ERK5 inhibitor BIX21088, thus supporting the result from the yeast phenotype screen. 相似文献