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841.
PAWEŁ JAŁOSZYŃSKI 《Systematic Entomology》2012,37(2):346-359
A new extinct species of the ant‐like stone beetle supertribe Mastigitae, Euroleptochromus sabathi gen. & sp.n. is described from Eocene Baltic amber. A phylogenetic analysis of Clidicini, with representatives of Leptomastacini and Mastigini as out‐group taxa, provided strong support for a sister‐group relationship between the Neotropical Leptochromus and the new genus. The monophyly of Clidicini is questioned because of an alternative placement of Nearctic Papusus as a sister taxon to Leptomastacini + [Clidicus + (Palaeoleptochromus + (Euroleptochromus + Leptochromus))]. A dispersal‐vicariance analysis provided three alternative scenarios for the evolution of Mastigitae; with Laurasia as the ancestral area of the supertribe, major branching events occurring within either Eurasia or Laurentia and two trans‐Beringia dispersals in Late Cretaceous and Eocene. Euroleptochromus, Palaeoleptochromus and Leptochromus share highly derived structures on postgenae and maxillary palps, probably as part of a specialised feeding or prey capture mechanism. The formation of these modifications in Clidicini is demonstrated to involve a process (traced back to the Campanian, 79 Ma) of elongation and narrowing of maxillary palps and forming a cuticular setal projection from a broadened insertion site of sensory setae. 相似文献
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Joanna Pastwińska Aurelia Walczak-Drzewiecka Magdalena Łukasiak Marcin Ratajewski 《Cell Adhesion & Migration》2020,14(1):106-117
ABSTRACTA decrease in oxygen concentration is a hallmark of inflammatory reactions resulting from infection or homeostasis disorders. Mast cells interact with extracellular matrix and other cells by adhesion receptors. We investigated the effect of hypoxia on integrin-mediated mast cell adhesion to fibronectin. We found that it was mediated by the α5/β1 receptor and that hypoxia significantly upregulated this process. Hypoxia-mediated increases in mast cell adhesion occurred without increased surface expression of integrins, suggesting regulation by inside-out integrin signaling. Hypoxia also mediated an increase in phosphorylation of Akt, and PI3’kinase inhibitors abolished hypoxia-mediated mast cell adhesion. Hypoxia upregulates the function of integrin receptors by PI3’ kinase-dependent signaling. This process might be important for the location of mast cells at inflammatory sites 相似文献
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Novel mutation in the BMPR1B gene (R486L) in a polish family and further delineation of the phenotypic features of BMPR1B‐Related brachydactyly 下载免费PDF全文
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Andrzej Klusiewicz Kinga Rbi Mariusz Ozimek Adam Czaplicki 《Biology of sport / Institute of Sport》2021,38(4):713
The objectives of this study were (1) to characterize the changes in oxygenation derived from muscle near-infrared spectroscopy (NIRS) during aerobic constant-load exercise with intensities close to Maximal Lactate Steady-State (MLSS) and (2) to establish reference values in the world-class rowers, for such workload often included in rowing training programs. Eight senior world-class rowers performed an incremental progressive submaximal exercise test and a 30-minute test on a rowing ergometer. The power corresponding to intensive aerobic training (84±1% of the anaerobic threshold) was adopted as an exercise load in the 30-minute test. The NIRS device was fixed on the vastus lateralis muscle which was active during rowing to record muscle O2 saturation (SmO2) and total hemoglobin concentration (THb) at rest and during exercise. Statistically significant increments in blood lactate (LA) and heart rate (HR) were observed, with 1.18±0.61 mmol/l and 10±5 beats/min, respectively, in 30th minute compared to 10th minute in 30-minute test. SmO2 decreased significantly by 2.9±1.4%, whereas THb did not change. The examinations may suggested the low diagnostic value of THb in constant-load exercise. In each subject, SmO2 was gradually reduced during the intense aerobic exercise. During workload close to MLSS, the SmO2 of the vastus lateralis ranged from 14.0±3.13 to 11.1±2.81% in 10 and 30 minutes respectively, with a reduction in muscle oxygenation (ΔSmO2) exceeding 50%. The non-invasive nature of the NIRS measurement and the continuous monitoring of SmO2 values are useful in the practice of monitoring training in terms of aerobic training loads. 相似文献
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