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1.
The phylogeny of the fungus gnat family Mycetophilidae (Diptera) is reconstructed with a focus on the species‐rich and taxonomically difficult subfamilies Gnoristinae and Mycomyinae. The multigene phylogenetic analyses are based on five nuclear (18S, 28S, CAD, MCS, ITS2) and four mitochondrial (12S, 16S, COI, CytB) gene markers. The analyses strongly support the monophyly of Mycetophilidae and the subfamilies Manotinae, Sciophilinae, Leiinae, and Mycomyinae, although Gnoristinae is paraphyletic with respect to Mycetophilinae. All the genera and groups of genera included are supported as monophyletic, except for Acomoptera Vockeroth, Boletina Staeger, Dziedzickia Johannsen, Ectrepesthoneura Enderlein, and Neoempheria Osten Sacken. Ancestral character state reconstructions were applied to two morphological features present in Gnoristinae and Mycomyinae (i.e. presence of setae on wing membrane and wing vein R4) in order to assess their evolution. The wing vein R4 appears as an unstable character, spread throughout different clades. A dated phylogeny of the family Mycetophilidae showed that most of the subfamilies of Mycetophilidae originated and diversified during the Cretaceous. The youngest subfamilies, originated in the Paleogene, appear to be Mycomyinae and Mycetophilinae. 相似文献
2.
Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
Background
With the growing number of public repositories for high-throughput genomic data, it is of great interest to combine the results produced by independent research groups. Such a combination allows the identification of common genomic factors across multiple cancer types and provides new insights into the disease process. In the framework of the proportional hazards model, classical procedures, which consist of ranking genes according to the estimated hazard ratio or the p-value obtained from a test statistic of no association between survival and gene expression level, are not suitable for gene selection across multiple genomic datasets with different sample sizes. We propose a novel index for identifying genes with a common effect across heterogeneous genomic studies designed to remain stable whatever the sample size and which has a straightforward interpretation in terms of the percentage of separability between patients according to their survival times and gene expression measurements. 相似文献3.
4.
Seabirds are affected by changes in the marine ecosystem. The influence of climatic factors on marine food webs can be reflected in long-term seabird population changes. We modelled the survival and recruitment of the Mediterranean storm petrel (Hydrobates pelagicus melitensis) using a 21-year mark-recapture dataset involving almost 5000 birds. We demonstrated a strong influence of prebreeding climatic conditions on recruitment age and of rainfall and breeding period conditions on juvenile survival. The results suggest that the juvenile survival rate of the Mediterranean subspecies may not be negatively affected by the predicted features of climate change, i.e., warmer summers and lower rainfall. Based on considerations of winter conditions in different parts of the Mediterranean, we were able to draw inferences about the wintering areas of the species for the first time. 相似文献
5.
L Chrobák D Radochová K Smetana F Mat?ja M Kout J Polák P Dít? J Pribrosky I Dvorácková 《Folia haematologica (Leipzig, Germany : 1928)》1980,107(4):628-640
These siblings of a Czech family aged 21, 19 and 6 years, respectively, with congenital dyserythropoietic anemia, type II, (HEMPAS) are reported. In two elder siblings ferrokinetic studies revealed a rapid plasma 59Fe clearance, markedly decreased erythrocyte incorporation and shortened 51Cr red-cell survival. Direct anti-globulin test was found positive in one of them. Further investigations revealed low values of blood plasma cholesterol, total lipids, beta-lipoproteins, beta-carotine and vitamin E and A as well as low values of the prothrombin complex. Liver biopsy demonstrated siderosis and disseminated intravascular coagulation in the liver in both patients. The possible reasons for these humoral aberrations are discussed. 相似文献
6.
7.
Nathalie Jeanray Rapha?l Marée Benoist Pruvot Olivier Stern Pierre Geurts Louis Wehenkel Marc Muller 《PloS one》2015,10(1)
Zebrafish is increasingly used to assess biological properties of chemical substances and thus is becoming a specific tool for toxicological and pharmacological studies. The effects of chemical substances on embryo survival and development are generally evaluated manually through microscopic observation by an expert and documented by several typical photographs. Here, we present a methodology to automatically classify brightfield images of wildtype zebrafish embryos according to their defects by using an image analysis approach based on supervised machine learning. We show that, compared to manual classification, automatic classification results in 90 to 100% agreement with consensus voting of biological experts in nine out of eleven considered defects in 3 days old zebrafish larvae. Automation of the analysis and classification of zebrafish embryo pictures reduces the workload and time required for the biological expert and increases the reproducibility and objectivity of this classification. 相似文献
8.
RegB is involved in the control of the phage T4 life cycle. It inactivates the phage early mRNAs when their translation is
no more required. We determined its structure and identified residues involved in substrate binding. For this, all backbone
and 90% of side-chain resonance frequencies were assigned. 相似文献
9.
A. Verrips Gerry C. H. Steenbergen-Spanjers J. A. F. M. Luyten R. A. Wevers John H. J. Wokke Fons J. M. Gabreëls Bert G. Wolthers Lambert P. W. J. van den Heuvel 《Human genetics》1997,100(2):284-286
We report a new mutation in the sterol 27-hydroxylase (CYP 27) gene in a Dutch family with cerebrotendinous xanthomatosis:
a G→A transition in the splice donor site in intron 4. This mutation leads to skipping of exon 4, resulting in a loss of 66
amino acids in the CYP 27 enzyme molecule.
Received: 15 March 1997 / Accepted: 26 March 1997 相似文献
10.