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341.
An infant-oriented parental repertoire contributes to an infant''s development and well-being. The role of oxytocin (OT) in promoting affiliative bonds and parenting has been established in numerous animal and human studies. Recently, acute administration of OT to a parent was found to enhance the carer''s, but at the same time also the infant''s, physiological and behavioural readiness for dyadic social engagement. Yet, the exact cues that are involved in this affiliative transmission process remain unclear. The existing literature suggests that motion and vocalization are key social signals for the offspring that facilitates social participation, and that distance and motion perception are modulated by OT in humans. Here, we employed a computational method on video vignettes of human parent–infant interaction including 32 fathers that were administered OT or a placebo in a crossover experimental design. Results indicate that OT modulates parental proximity to the infant, as well as the father''s head speed and head acceleration but not the father''s vocalization during dyadic interaction. Similarly, the infant''s OT reactivity is positively correlated with father''s head acceleration. The current findings are the first to report a relationship between the OT system and parental motion characteristics, further suggesting that the cross-generation transmission of parenting in humans might be underlaid by nuanced, infant-oriented, gestures relating to the carer''s proximity, speed and acceleration within the dyadic context.  相似文献   
342.
Virgin fruit fly females were stressed by placement into a confined space without food for 2.5 hours. Some flies were subjected to terahertz radiation (0.1–2.2 THz) for the last 30 min. Then females were copulated with males. Offspring F1 from oocytes which were mature or immature at exposure (oviposition in 1–2 or 9–10 days after irradiation) was studied. Stress induces a rejection of the offspring maturation dynamics to imago from external control (offspring of flies which was maintained in standard conditions). In offsping from mature oocytes of irradiated flies the dynamics of male maturation to imago was different from internal control (offspring of stressed unirradiated flies). The number of imago males decreased. The dynamics of female maturation to imago coincides with laboratory control. In offsping from immature oocytes of irradiated flies the dynamics of female and male maturation and the number of flies were not significantly different from the internal control. It was concluded that only mature oocytes are sensitive to THz radiation influence.  相似文献   
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The kidney is one of the key organs in clearing foreign compounds. The effects of drugs on the developing kidney are relatively unknown. We studied the direct effect of furosemide, hydrochlorothiazide, ibuprofen, and indomethacin on kidney development in an ex vivo embryonic kidney model. At embryonic day 13, metanephroi were dissected from mice and cultured in control media or media supplemented with various clinically relevant concentrations of drugs. The ureteric tree was visualized by whole‐mount staining and branching was evaluated by counting. Additionally, gene expression levels of Wt1, Sox9, Bmp7, Fgf8, and Gdnf were investigated. No distinct differences were noted on either ureteric tip development or gene expression analysis for each drug after 24 hr of exposure. Even though short‐term exposure to clinically relevant concentrations seems not to disturb renal development, future research is needed to study prolonged or repeated exposures.  相似文献   
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Localization of antisera to neurofilament antigens derived from rat peripheral nerve was carried out in tissues of rat and human peripheral and central nervous systems by indirect immunofluorescence. Unfixed and chloroform-methanol-fixed frozen sections of tissues were incubated in purified IgG of the experimental rabbit antisera and subsequently exposed to goat anti-rabbit IgG conjugated with fluorescein isothiocyanate. Control studies were conducted on identical tissue preparations incubated in the same concentrations of nonspecific rabbit IgG or in experimental rabbit IgG absorbed with extracts of rat peripheral nerve containing neurofilament antigen. Extensive immunofluorescence was observed in rat and human peripheral and central nervous systems. The distribution and configuration of immunofluorescence corresponded to neurofilament-rich structural components of these tissues. Prominent immunofluorescence was also noted in neuronal cell bodies of spinal sensory ganglia, especially in perikarya of the large neuronal type. Immunofluorescence of the central nervous system was located predominantly in myelinated axons of the white matter in cerebrum, cerebellum, brain stem, and spinal cord. Less intense immunofluorescence was also seen in neuronal perikarya and in short thin linear processes of grey matter.  相似文献   
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Abstract:  The taxonomy, biostratigraphical and palaeogeographical distribution of the Lower Ordovician graptolite genus Bryograptus is evaluated. Bryograptus is recognized as a distinct triradiate anisograptid with a multiramous, pendent rhabdosome. The species of the genus Bryograptus can be interpreted as shallow water faunal elements with a strongly limited biogeographical distribution to the Atlantic Faunal Realm. Bryograptus is restricted to a narrow interval in the Upper Tremadocian, the Bryograptus Biozone of Scandinavia and South America (Argentina), making it a taxon with a high potential for precise biostratigraphical correlations. The proximal end development can be used to differentiate the genus Bryograptus from other pendent multiramous graptoloid genera with a homoplastic rhabdosome development. Characteristics of the proximal end development and structure easily differentiate these genera in relief specimens, but not in flattened material.  相似文献   
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Glutamate dehydrogenase extracted from wheat leaves ( Triticum aestivum L. cv. Capitole) taken at two different physiological stages was analysed by electrophoretic and immune-chemical techniques. Two NAD-dependent antigens were identified which bear the balk of the glutamate dehydrogenase activity in the two extracts. The first enzyme was found in much larger amounts in young than in senescent leaves and the reverse situation was observed for the second antigen. The possible relationships between this antigenic polymorphism and the heterogeneity detected by isoelectric focusing from the two extracts were investigated. A charge heterogeneity (isoelectric points about 5.7 and 4.8) was found for the first antigen in both extracts. The second antigen appeared homogeneous (isoelectric point about 5.7) at least in senescent leaves. The last result indicates that two quite different antigens appear in the same isoelectric focusing zone.  相似文献   
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