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Glotsos D Tohka J Ravazoula P Cavouras D Nikiforidis G 《International journal of neural systems》2005,15(1-2):1-11
A computer-aided diagnosis system was developed for assisting brain astrocytomas malignancy grading. Microscopy images from 140 astrocytic biopsies were digitized and cell nuclei were automatically segmented using a Probabilistic Neural Network pixel-based clustering algorithm. A decision tree classification scheme was constructed to discriminate low, intermediate and high-grade tumours by analyzing nuclear features extracted from segmented nuclei with a Support Vector Machine classifier. Nuclei were segmented with an average accuracy of 86.5%. Low, intermediate, and high-grade tumours were identified with 95%, 88.3%, and 91% accuracies respectively. The proposed algorithm could be used as a second opinion tool for the histopathologists. 相似文献
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Ioakim-Liossi A Mikou P Botsoli-Stergiou E Petrakakou E Athanassiadou P Kordosis T Panagiotakopoulos G Karakitsos P 《Acta cytologica》2004,48(2):269-272
BACKGROUND: Primary effusion lymphoma (PEL) is a rare type of lymphoma that presents as an effusion, seldom with evidence of a solid neoplasm elsewhere; thus, cytology is the basic diagnostic method. It usually occurs in HIV-positive males with a history of Kaposi's sarcoma (KS), and DNA sequences of human herpesvirus 8 (HHV-8) are detected by molecular analysis. The distinct morphologic, immunophenotypic, molecular and clinical characteristics render this neoplasm a new pathologic entity. CASE: A 57-year-old, HIV-positive man presented to the hospital with ascites and absence of neoplasm on radiologic investigation. Cytologic evaluation of the ascitic fluid revealed the presence of highly atypical, pleomorphic lymphoid cells. Immunocytochemistry of the lymphoma cells was positive for CD45 (leukocyte common antigen), CD30 and epithelial membrane antigen antigens and negative for panB, panT and cytokeratin antigens. DNA sequences of HHV-8 were identified by polymerase chain reaction (PCR), and DNA ploidy analysis showed aneuploidy. The patient died 5 months after the diagnosis. CONCLUSION: Conventional and ThinPrep (Cytyc Corp., Boxborough, Massachusetts, U.S.A.) cytology, in combination with immunocytochemistry and PCR for HHV-8 DNA sequences, can lead to an accurate diagnosis of PEL. DNA ploidy analysis confirms the aggressive nature of this neoplasm. 相似文献
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Novel GES/IBC extended-spectrum beta-lactamase variants with carbapenemase activity in clinical enterobacteria 总被引:5,自引:0,他引:5
Vourli S Giakkoupi P Miriagou V Tzelepi E Vatopoulos AC Tzouvelekis LS 《FEMS microbiology letters》2004,240(2):209-213
Two clinical isolates, an Escherichia coli and a Klebsiella pneumoniae, with decreased susceptibility to carbapenems were studied. This phenotype was associated with production of novel GES/IBC variant beta-lactamases, designated GES-3 (from E. coli) and GES-4 (from K. pneumoniae), exhibiting carbapenemase activity. Both enzymes possessed Ser at Ambler's position 170 instead of Gly found in the beta-lactamases GES-1 and IBC-1 that lack carbapenemase activity. Additionally, position 104 in GES-4 was occupied by a Lys as in IBC-1. bla(GES-3) and bla(GES-4) occurred as gene cassettes in the variable regions of class 1 integrons carried by plasmids. The structure of the GES-4-encoding integron was similar to that of previously described IBC-1 integrons. The GES-3-encoding integron was, most likely, truncated at the 3' conserved segment. 相似文献
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Flower preferences and pollen transport networks for cavity‐nesting solitary bees: Implications for the design of agri‐environment schemes
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Catherine E. A. Gresty Elizabeth Clare Dion S. Devey Robyn S. Cowan Laszlo Csiba Panagiota Malakasi Owen T. Lewis Katherine J. Willis 《Ecology and evolution》2018,8(15):7574-7587
Floral foraging resources are valuable for pollinator conservation on farmland, and their provision is encouraged by agri‐environment schemes in many countries. Across Europe, wildflower seed mixtures are widely sown on farmland to encourage pollinators, but the extent to which key pollinator groups such as solitary bees exploit and benefit from these resources is unclear. We used high‐throughput sequencing of 164 pollen samples extracted from the brood cells of six common cavity‐nesting solitary bee species (Osmia bicornis, Osmia caerulescens, Megachile versicolor, Megachile ligniseca, Megachile centuncularis and Hylaeus confusus) which are widely distributed across the UK and Europe. We documented their pollen use across 19 farms in southern England, UK, revealing their forage plants and examining the structure of their pollen transport networks. Of the 32 plant species included currently in sown wildflower mixes, 15 were recorded as present within close foraging range of the bees on the study farms, but only Ranunculus acris L. was identified within the pollen samples. Rosa canina L. was the most commonly found of the 23 plant species identified in the pollen samples, suggesting that, in addition to providing a nesting resource for Megachile leafcutter bees, it may be an important forage plant for these species. Higher levels of connectance and nestedness were characteristic of pollen transport networks on farms with abundant floral resources, which may increase resilience to species loss. Our data suggest that plant species promoted currently by agri‐environment schemes are not optimal for solitary bee foraging. If a diverse community of pollinators is to be supported on UK and European farmland, additional species such as R. canina should be encouraged to meet the foraging requirements of solitary bees. 相似文献
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Eugenia M. Rapoport Sergey V. Khaidukov Andrey M. Gaponov Galina V. Pazynina Svetlana V. Tsygankova Ivan M. Ryzhov Ivan M. Belyanchikov Panagiota Milona Nicolai V. Bovin Kenneth C. McCullough 《Glycoconjugate journal》2018,35(2):191-203
Dendritic cells (DCs) play crucial roles in innate and adaptive immune response, for which reason targeting antigen to these cells is an important strategy for improvement of vaccine development. To this end, we explored recognition of DCs lectins by glycans. For selection of the glycan “vector”, a library of 229 fluorescent glycoprobes was employed to assess interaction with the CD14low/-CD16+CD83+ blood mononuclear cell population containing the DCs known for their importance in antigen presentation to T-lymphocytes. It was found that: 1) the glycan-binding profiles of this CD14low/-CD16+CD83+ subpopulation were similar but not identical to DCs of monocyte origin (moDCs); 2) the highest percentage of probe-positive cells in this CD14 low/-CD16+CD83+ subpopulation was observed for GalNAcα1-2Galβ (Adi), (Neu5Acα)3 and three mannose-reach glycans; 3) subpopulation of CD14low/-CD16+ cells preferentially bound 4’-O-Su-LacdiNAc. Considering the published data on specificity of DCs binding, the glycans showing particular selectivity for the CD14 low/-CD16+CD83+ cells are likely interacting with macrophage galactose binding lectin (MGL), siglec-7 and dectin-2. In contrast, DC-SIGN is not apparently involved, even in case of mannose-rich glycans. Taking into consideration potential in vivo competition between glycan “vectors” and glycans within glycocalyx, attempting to target vaccine to DCs glycan-binding receptors should focus on Adi and (Neu5Acα)3 as the most promising vectors. 相似文献
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