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941.
Marianne Maquart Sébastien Boyer Vincent Michel Rakotoharinome Julie Ravaomanana Michael Luciano Tantely Jean-Michel Heraud Eric Cardinale 《PloS one》2016,11(1)
West Nile virus is an arthropod-borne zoonosis transmitted by a large number of mosquito species, and birds play a key role as reservoir of the virus. Its distribution is largely widespread over Africa, Asia, the Americas and Europe. Since 1978, it has frequently been reported in Madagascar. Studies described a high seroprevalence level of the virus in humans in different areas of the island and a human fatal case of WNV infection was reported in 2011. Despite these reports, the epidemiology of WNV in Madagascar, in particular, viral circulation remains unclear. To explore the transmission of WNV in two rural human populations of Madagascar, we investigated local mosquitoes and poultry for evidence of current infections, and determined seroprevalence of candidate sentinel species among the local poultry. These 2 areas are close to lakes where domestic birds, migratory wild birds and humans coexist. Serological analysis revealed WNV antibodies in domestic birds (duck, chicken, goose, turkey and guinea fowl) sampled in both districts (Antsalova 29.4% and Mitsinjo 16.7%). West Nile virus nucleic acid was detected in one chicken and in 8 pools of mosquitoes including 2 mosquito species (Aedeomyia madagascarica and Anopheles pauliani) that have not been previously described as candidate vectors for WNV. Molecular analysis of WNV isolates showed that all viruses detected were part of the lineage 2 that is mainly distributed in Africa, and were most closely matched by the previous Malagasy strains isolated in 1988. Our study showed that WNV circulates in Madagascar amongst domestic birds and mosquitoes, and highlights the utility of poultry as a surveillance tool to detect WNV transmission in a peri-domestic setting. 相似文献
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Background
A retrospective study of rabbits treated against cheyletiellosis was performed to evaluate the efficacy and safety of selamectin or ivermectin in clinical practice. 相似文献943.
944.
Marianne Führers 《Cell and tissue research》1939,30(1):52-66
Zusammenfassung Während eine Epithelsprosse größer wird, bleibt das angrenzende Mesenchym im Wachstum zurück. Dieses breitet sich mit seiner Substanz in geringerem Umfange als das angrenzende Mesenchym aus (Abb. 2 und 3). Dadurch entsteht zwischen diesen beiden Mesenchymbezirken eine Volumdifferenz. Diese Differenz gleicht die wachsende Epithelsprosse aus.Was dabei speziell den sog. Haarstrich beim Menschen betrifft, ist folgendes feststellbar: Der Haarstrich zeigt die Wachstumsbewegung der Haut an. Diese wächst metamer, ohne daß dabei die einzelnen Metamere scharf gegeneinander abgegrenzt werden (Abb. 9 und 10). Da jedes Metamer (ähnlich etwa den Muskelsegmenten bei Fischen) tütenförmig angelegt wird (vgl. Abb. 11 und 12), so wächst die ganze Haut relativ zu ihrer Unterlage schräg (und zwar schräg nach außen kaudal, Abb. 13). Es scheint, daß alle Metamere der Haut nahezu gleichmäßig wachsen (Abb. 12), daß aber die kranialen früher mit ihrem Wachstum beginnen und auch früher enden. (Das Kopfhaar entsteht bekanntlich unter allen Haaren zuerst, es allein wird besonders lang und es fällt unter Umständen frühzeitig für immer aus.)Das Wesentliche ist: Der Haarstrich (Abb. 13) ergibt sich daraus, daß der Organismus vom Primitivknoten aus exzentrisch in kranialer Richtung wächst (Abb. 11 bzw. 12).Die vorliegende Abhandlung wurde auf Anregung von Dozent E. Blechschmidt ausgeführt. Die Untersuchung ist die Fortsetzung zu der konstruktiven Entwicklung des kranio-kaudalen Haarstrichs, I. Mitteilung. Blechschmidt: 44. Verslg Verh. Anat. Ges. Mailand 1936. 相似文献
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In swimming sharks, vertebrae are subjected, in part, to compressive loads as axial muscles contract. We currently have no information about which vertebral elements, centra, arch cartilages, or both, actually bear compressive loads in cartilaginous vertebrae. To address this issue, the goal of this experiment was to determine the load‐bearing ability of arch and centrum cartilages in compression, to determine the material properties of shark vertebrae, and to document fracture patterns in the centra with and without the arches. Intact vertebrae and vertebrae with the arch cartilages experimentally removed (centra alone) were subjected to compressive loading to failure at a single strain rate. The maximum compressive forces sustained by the vertebrae and the centra are statistically indistinguishable. Thus we conclude that under these testing conditions the arch does not bear appreciable loads. Independent evidence for this conclusion comes from the fact that vertebrae fail in compression at the centra, and not at the arches. Overall, the results of these mechanical tests suggest that the neural arches are not the primary load‐bearing structure during axial compression. J. Morphol. 2010. © 2009 Wiley‐Liss, Inc. 相似文献
948.
Judith Semon Dubas Marianne Heijkoop Marcel A. G. van Aken 《Human nature (Hawthorne, N.Y.)》2009,20(1):80-92
The role of olfaction in kin recognition and parental investment is documented in many mammalian/vertebrate species. Research
on humans, however, has only focused on whether parents are able to recognize their children by smell, not whether humans
use these cues for investment decisions. Here we show that fathers exhibit more affection and attachment and fewer ignoring
behaviors toward children whose smell they can identify than toward those whose smell they cannot recognize. Thus, olfaction
might serve as a means for males to determine their genetic relatedness to purported offspring. We also demonstrate that mothers’
olfactory recognition and hedonistic ratings are linked with the use of physical punishment. Mothers report using more punishment
with children whose odor they cannot recognize and less with children whose odor they rated as more pleasant. These results
provide the first preliminary evidence in humans that olfactory cues may guide parents in the allocation of care. 相似文献
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