نتایج جستجو برای: feather

تعداد نتایج: 3717  

Journal: :The Journal of veterinary medical science 2009
Yu YAMAMOTO Kikuyasu NAKAMURA Manabu YAMADA Toshihiro ITO

We examined whooper swans naturally infected with avian influenza virus (H5N1) to evaluate the possible zoonotic risk of swan feathers. Viruses were isolated from feather calami. Immunohistochemical testing revealed that virus antigens were present in the feather epidermis and feather follicle wall epidermis of some feathers. RT-PCR and genetic sequencing using paraffin sections of swan feather...

2015
Cathleen Chiu Cheng Ming Chuong

Through cyclic regeneration, feather stem cells are molded into different shapes under different physiological states. With its distinct morphology, context-dependent growth, and experimental manipulability, the feather provides a rich model to study growth control, regeneration, and morphogenesis in vivo. Recent examples include novel insights revealed by transient perturbation with chemothera...

Journal: :General and comparative endocrinology 2015
Rebecca J Strong M Glória Pereira Richard F Shore Peter A Henrys Tom G Pottinger

This study investigated the feasibility of measuring corticosterone in feathers from cryo-archived raptor specimens, in order to provide a retrospective assessment of the activity of the stress axis in relation to contaminant burden. Feather samples were taken from sparrowhawk Accipiter nisus, kestrel Falco tinnunculus, buzzard Buteo buteo, barn owl Tyto alba, and tawny owl Strix aluco and the ...

2014
Sophie Bourgeon Eliza H. K. Leat Ellen Magnusdóttir Robert W. Furness Hallvard Strøm Aevar Petersen Geir W. Gabrielsen Sveinn Are Hanssen Jan Ove Bustnes

Environmental conditions encountered by migratory seabirds in their wintering areas can shape their fitness. However, the underlying physiological mechanisms remain largely unknown as birds are relatively inaccessible during winter. To assess physiological condition during this period, we measured corticosterone concentrations in winter-grown primary feathers of female great skuas (Stercorarius...

Journal: :The Journal of Cell Biology 1985
C M Chuong G M Edelman

The potential relationship of cell adhesion to embryonic induction during feather formation was examined by immunohistochemical analysis of the spatiotemporal distribution of three cell-adhesion molecules (CAMs), neural CAM (N-CAM), liver CAM (L-CAM), and neuron-glia CAM (Ng-CAM), and of substrate molecules (laminin and fibronectin) in embryonic chicken skin. The N-CAM found at sites of embryon...

2011
SL Yang RS Gao PL Niu ZY Zou RH Yu

A complex three-dimensional (3D) feather-like AlN nanostructure was synthesized by a direct reaction of high-purity Al granules with nitrogen using an arc discharge method. By adjusting the discharge time, a coral-like nanostructure, which evolved from the feather-like nanostructure, has also been observed. The novel 3D feather-like AlN nanostructure has a hierarchical dendritic structure, whic...

2011
Menandro N. Acda

This study investigated the use of waste chicken feather (barbs and rachis) as reinforcement in cement-bonded composites. A series of composite boards consisting of various proportions of waste feather, cement, sand, and chemical admixtures were prepared. Mix workability decreased significantly as the proportion by weight of feathers or ground feathers increased from 5% to 20%. Boards containin...

Journal: :Development 2004
Markus Mandler Annette Neubüser

Morphogenesis of hairs and feathers is initiated by an as yet unknown dermal signal that induces placode formation in the overlying ectoderm. To determine whether FGF signals are required for this process we over-expressed soluble versions of FGFR1 or FGFR2 in the skin of chicken embryos. This produced a complete failure of feather formation prior to any morphological or molecular signs of plac...

Journal: :Developmental biology 2004
Iain W McKinnell Mark Turmaine Ketan Patel

Feathers are formed following a series of reciprocal signals between the epithelium and the mesenchyme. Initially, the formation of a dense dermis leads to the induction of a placode in the overlying ectoderm. The ectoderm subsequently signals back to the dermis to promote cell division. Sonic Hedgehog (Shh) is a secreted protein expressed in the ectoderm that has previously been implicated in ...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2006
Zhicao Yue Ting-Xin Jiang Randall Bruce Widelitz Cheng-Ming Chuong

The evolution of bilaterally symmetric feathers is a fundamental process leading toward flight. One major unsolved mystery is how the feathers of a single bird can form radially symmetric downy feathers and bilaterally symmetric flight feathers. In developing downy feather follicles, barb ridges are organized parallel to the long axis of the feather follicle. In developing flight-feather follic...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید