The primitive streak is the organizing center for amniote gastrulation. It defines the future embryonic midline and serves as a conduit of cell migration for germ layer formation. The migration patterns of endodermal and mesodermal precursors through the streak have been studied in great detail. Additional new breakthroughs recently have revealed the cell biological and molecular mechanisms tha...

The origin of the presumptive nephrogenic cells in the epiblast of the chick embryo was traced by radioautographic analysis of the movements of tritiated thymidine-labelled grafts excised from medium-streak to 5-somite stage embryos and transplanted to epiblast, streak, and the endoderm-mesoderm layer of similarly staged recipient embryos. The nephrogenic cells originate near the area pellucida...

The body plan of all higher organisms develops during gastrulation. Gastrulation results from the integration of cell proliferation, differentiation and migration of thousands of cells. In the chick embryo gastrulation starts with the formation of the primitive streak, the site of invagination of mesoderm and endoderm cells, from cells overlaying Koller's Sickle. Streak formation is associated ...

The aim of this study is to report clinical course of choroidal neovascularization secondary to angioid streaks (AS) in two patients who underwent intravitreal bevacizumab therapy. Fundus examination, fluorescein angiography (FA) and optical coherence tomography (OCT) revealed the diagnosis of subfoveal classic choroidal neovascularization (CNV) in the right eye in patient 1 and in the left eye...

Morphogenetic movements occurring during formation of the primitive streak in the chick embryo are of a periodic nature, with a mean frequency of one pulse every 2.6 min. The period of the oscillatory movement is shown to be temperature-dependent. The onset of these pulses of movement can be seen as a slow wave starting at the posterior end of the embryo and making its way towards the anterior ...

In mammals, the primitive streak region and its descendant, the tail bud, are the source of nascent mesoderm and spinal cord throughout axial elongation. A localised population of long-term axial progenitors has been identified in a region of the tail bud, the chordoneural hinge, but the localisation of such progenitors at earlier stages is so far untested. By studying gene expression, we have ...

abstract objective: to investigate the effect of an anti-inflammatory drug (piroxicam) on the development of fatty streak in rabbits. methods: male rabbits were fed with four types of regimen: a) normal rabbit chow, b) 1% cholesterol diet c) cholesterol diet plus piroxicam, d) normal rabbit chow plus piroxicam. after 12 weeks, the animals were sacrificed and the aorta, as well as the right and ...

A 40-year old female came with complaints of headache for 5 days. Her general examination and vitals were within normal limits. On complete ophthalmic we found there are irregular streaks radiating from disc in the fundus both eyes suggesting angioid streaks. We did a dermatological evaluation view increased stretchability skin papules over neck & thigh diagnosed as pseudoxanthoma elasticum...

Initial tests of a dual-sweep streak system planned for use on the Advanced Photon Source (APS) have been performed using assets of the Argonne Wakefield Accelerator (AWA) facility. The short light pulses from the photoelectric injector drive laser in both the visible (-96 nm, AtI .5 ps (FWHM)), and the ultraviolet (k 248 nm, At-5 ps (FWHM)) were used. Both a W-visible S20 photocathode streak t...