Search results for "Homing"
showing 10 items of 61 documents
Delayed healing of chronic leg ulcers can result from impaired trafficking of bone marrow-derived precursors of keratinocytes to the skin
2006
In this paper, it is hypothesized that in chronic wounds the process of homing of bone marrow-derived precursors of keratinocytes is disturbed, and that the interaction between cutaneous T-cell attracting chemokine (CTACK/CCL27) and soluble P-selectin glycoprotein ligand-1 (PSGL-1) can be the cause of this impairment. Several studies have revealed that bone marrow-derived cells (BMDC) trans-differentiate into various cellular lineages, and probably they participate also in healing of wounded skin. Recent studies have demonstrated that BMDC can engraft into the epidermis, and probably they do not engraft into epidermis as keratinocyte stem cells, but rather as transient amplifying cells. So,…
Reproductive costs and litter size in the bank vole.
1995
The potential reproductive costs for free-ranging bank vole (Clethrionomys glareolus) offspring and mothers were assessed by manipulating litter size and by determining the effects of nursing varied numbers of offspring. Litter enlargement did not increase the number of weanlings per mother. The mass of juveniles was significantly lower in the enlarged litters and higher in the reduced litters, compared to the control group. However, the survival of juveniles from weaning aged three months did not depend on their mass at weaning. Data from a previous study (Mappes et al. 1995) indicated that a higher mass at weaning may increase juveniles' abilities to maturate and breed during their summer…
Spatial segregation of home ranges between neighbouring colonies in a diurnal raptor
2018
AbstractEnhancement of information transfer has been proposed as a key driver of the evolution of coloniality. Transfer of information on location of food resources implies that individuals from the same colony share foraging areas and that each colony can be associated to a specific foraging area. In colonial breeding vertebrates, colony-specific foraging areas are often spatially segregated, mitigating intercolony intraspecific competition. By means of simultaneous GPS tracking of lesser kestrels (Falco naumanni) from neighbouring colonies, we showed a clear segregation of space use between individuals from different colonies. Foraging birds from different neighbouring colonies had home r…
On the socio-sexual behaviour of the extinct ursid Indarctos arctoides: an approach based on its baculum size and morphology
2013
The fossil bacula, or os penis, constitutes a rare subject of study due to its scarcity in the fossil record. In the present paper we describe five bacula attributed to the bear Indarctos arctoides Depéret, 1895 from the Batallones-3 site (Madrid Basin, Spain). Both the length and morphology of this fossil bacula enabled us to make interpretative approaches to a series of ecological and ethological characters of this bear. Thus, we suggest that I. arctoides could have had prolonged periods of intromission and/or maintenance of intromission during the post-ejaculatory intervals, a multi-male mating system and large home range sizes and/or lower population density. Its size might also have he…
Prenatal exposure to the CB1 receptor agonist WIN 55,212-2 causes learning disruption associated with impaired cortical NMDA receptor function and em…
2005
The aim of this study was to investigate whether prenatal exposure to the cannabinoid CB1 receptor agonist WIN 55,212-2 (WIN) at a daily dose devoid of overt signs of toxicity and/or gross malformations (0.5 mg/kg, gestation days 5-20), influences cortical glutamatergic neurotransmission, learning and emotional reactivity in rat offspring. Basal and K+-evoked extracellular glutamate levels were significantly lower in cortical cell cultures obtained from pups exposed to WIN during gestation with respect to those measured in cultures obtained from neonates born from vehicle-treated dams. The addition of NMDA to cortical cell cultures from neonates born from vehicle-treated dams concentration-…
Unusual B cell morphology in inflammatory bowel disease.
2012
B lymphocytes express various different types of surface immunoglobulins that are largely unrelated to other hematological lines, although some reports have described a relationship between malignant B cells and other cells such as macrophages. Multiple genes of hematopoietic lineage, including transcription factors, are co-expressed in hematopoietic stem cells and progenitors, a phenomenon referred to as "lineage priming". Changes in the expression levels and timing of transcription factors can induce the lineage conversion of committed cells, which indicates that the regulation of transcription factors might be particularly critical for maintaining hierarchical hematopoietic development. …
Emergence and dispersal relative to natal nest in the digger wasp Stizus continuus (Hymenoptera: Crabronidae).
2009
The position of the emerging point has rarely been investigated as a factor possibly affecting the future nest settlement behaviour in Hymenoptera, in particular within nest aggregations. We studied the emergence and dispersion patterns of the digger wasp Stizus continuus. Individuals emerged daily in clumped patterns, possibly revealing a certain synchrony of emergence from the same nests, and protandry appeared both at seasonal and daily level. Differences between the number of females that nested relatively close or far from their emergence holes (EH) were either significant or not, depending on the year, and observed dispersal distances from the natal nests did not differ from those obt…
Territoriality in the Sheet-Web Spider Linyphia triangularis (Clerck) (Araneae, Linyphiidae
2010
Zusammenfassung 1 Das adulte L. triangularis-♂ bleibt bis zu 2 Tagen im Netz eines ♀, betrachtliche Zeit verbringt es von Netz zu Netz wandernd. Wahrend der Zeit des gemeinsamen Netzaufenthaltes ist das ♂, ob das ♀ nun kopulationsbereit ist oder nicht, stets der dominante Teil des Paares. 2 Wenn mehrere ♂♂ im ♀-Netz zusammentreffen, zeigen sie Droh- und Kampfverhalten, in dem die vergroserten Chelizeren und Klauen benutzt werden. Mehrere Stufen des Kampfverhaltens werden beschrieben und als Aggressionsanzeiger betrachtet. 3 Netzreduktion durch das ♂ wird als Methode zur Verhinderung von Storungen wahrend der Kopulation betrachtet. Selektionsmechanismen, die die Evolution solchen Verhaltens …
Multihoming in the Market for Payment Media: Evidence from Young Finnish Consumers
2004
Tassa tutkimuksessa tarkastellaan sita, miksi jotkut kuluttajista kayttavat vain yhta maksuvalinetta ja toiset kuluttajat monia maksuvalineita maksaessaan paivittaisia ostoksiaan. Kayttamalla aineistoa nuorista suomalaisista kuluttajista loydamme, etta yksi tarkeimmista maksuvalineiden kayttoon vaikuttavista tekijoista on kuluttajien yleinen tietoisuus maksamiseen liittyvista kysymyksista. Instrumenttimuuttujaestimoinnit osoittavat, etta paremmin tietoiset kuluttajat kayttavat 1.2-1.3 kertaa useampaa maksuvalinetta kuin vahemman tietoiset kuluttajat. Koska monia uusia maksuvalineita kaytetaan usein aluksi olemassa olevien maksuvalineiden rinnalla, tuloksemme tukevat nakemysta, etta kuluttaj…
The “mode” of lymphocyte extravasation through HEV of Peyer's patches and its role in normal homing and inflammation
2007
The mode of lymphocyte transendothelial migration in the postcapillary high endothelial venules (HEVs) of Peyer's patches during normal homing and acute inflammation in the guinea pig was studied. It is common opinion that the lymphocyte transendothelial passage from the blood stream into the extravasal lymphoid tissue calls for a multistep process of endothelial and lymphocyte molecules favoring tethering, rolling, activation, arrest and its firm adhesion to the endothelial luminal surface. Ultrastructural serial pictures and the three-dimensional reconstruction of HEVs with lymphocytes during different moments of their transmigration through the endothelial wall enabled us to demonstrate …