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571.
R. PANADERO G. VARAS G. PAJARES F. MARKINA C. LÓPEZ P. DÍAZ A. PÉREZ‐CREO A. PRIETO P. DÍEZ‐BAÑOS P. MORRONDO 《Medical and veterinary entomology》2017,31(1):94-96
Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4–5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed. 相似文献
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Richard F. Ambrose 《Marine and Freshwater Behaviour and Physiology》2013,45(2):137-144
Many octopus species consume their prey in a shelter, where discarded prey items accumulate to form a midden. The shelters of Octopus bimaculatus rarely have middens. Some discarded prey items are present at 20% of the shelters of O. bimaculatus, but these do not accumulate to form middens. A field experiment using artificial middens demonstrated that currents and/or surge moved some bivalve shells, and hermit crabs rapidly removed snail shells from the middens. Snails are very important in the diet of O. bimaculatus but not most other octopus species; middens do not form around O. bimaculatus shelters because hermit crabs remove the discarded snail shells. 相似文献
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Sheng-He Huang Yu-Hua Chen Guoying Kong Steven H. Chen John Besemer Mark Borodovsky Ambrose Jong 《Functional & integrative genomics》2001,1(5):312-322
The IbeA (ibe10) gene is an invasion determinant contributing to E. coli K1 invasion of the blood-brain barrier. This gene has been cloned and characterized from the chromosome of an invasive cerebrospinal
fluid isolate of E. coli K1, strain RS218 (018:K1: H7). In the present study, a genetic island of meningitic E. coli containing ibeA (GimA) has been identified. A 20.3-kb genomic DNA island unique to E. coli K1 strains has been cloned and sequenced from an RS218 E. coli K1 genomic DNA library. Fourteen new genes have been identified in addition to the ibeA. The DNA sequence analysis indicated that the ibeA gene cluster was localized to the 98 min region and consisted of four operons, ptnIPKC, cglDTEC, gcxKRCI and ibeRAT. The G+C content (46.2%) of unique regions of the island is substantially different from that (50.8%) of the rest of the E. coli chromosome. By computer-assisted analysis of the sequences with DNA and protein databases (GenBank and PROSITE databases),
the functions of the gene products could be anticipated, and were assigned to the functional categories of proteins relating
to carbon source metabolism and substrate transportation. Glucose was shown to enhance E. coli penetration of human brain microvascular endothelial cells and exogenous cAMP was able to block the stimulating effect of
glucose, suggesting that catabolic regulation may play a role in control of E. coli K1 invasion gene expression. Our data suggest that this genetic island may contribute to E. coli invasion of the blood-brain barrier through a carbon-source-regulated process.
Electronic Publication 相似文献
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Leaf spongy mesophyll cells form an interconnected network of branched cells and intercellular spaces to maximize the surface area available for light capture and photosynthetic gas exchange. To investigate the morphogenetic events leading to cell separation and branching in Arabidopsis thaliana, we used mesophyll-specific promoters to facilitate imaging of mesophyll cell shape and microtubule (MT) organization over multiple spatiotemporal scales without interference from the overlying epidermal cells. We show that cells enlarge by selective expansion of cell wall regions in contact with intercellular spaces. Cell–cell contacts remain relatively fixed in size, forming the termini of interconnecting branches. Surprisingly, classic schizogeny (de-adhesion of neighboring cells) is relatively infrequent, being related to the local topology of cell junctions during early expansion. Intercellular spaces cue the position of stable MT bundles, which in turn promote efficient dilation of intercellular spaces and cell branching. Our data provide insights into mesophyll morphogenesis and MT organization and lay the groundwork for future investigations.Live imaging reveals a positive feedback loop between cell expansion and microtubule organization that facilitates efficient cell branching and intercellular space dilation in spongy mesophyll cells. 相似文献
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