Blood vessel formation when new vessels emerge from the proliferation of pre-existing blood vessels [goid 1525] [pmid 11427521] [evidence IDA]; The differentiation of endothelial cells from progenitor cells during blood vessel development, and the de novo formation of blood vessels and tubes [goid 1570] [pmid 15015550] [evidence TAS]; A change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a stimulus indicating lowered oxygen tension. Hypoxia, defined as a decline in O2 levels below normoxic levels of 20.8 - 20.95%, results in metabolic adaptation at both the cellular and organismal level [goid 1666] [pmid 16490744] [evidence IDA]; Any process that activates or increases the rate or extent of endothelial cell proliferation [goid 1938] [pmid 9202027] [evidence IDA]; Any process that activates or increases the rate or extent of endothelial cell proliferation [goid 1938] [evidence ISS]; Any process that activates or increases the frequency, rate, or extent of leukocyte migration [goid 2687] [pmid 1312256] [evidence TAS]; The biological process whose specific outcome is the progression of a multicellular organism over time from an initial condition (e.g. a zygote or a young adult) to a later condition (e.g. a multicellular animal or an aged adult) [goid 7275] [evidence IEA]; The process whose specific outcome is the progression of nervous tissue over time, from its formation to its mature state [goid 7399] [pmid 15351965] [evidence TAS]; Any process that modulates the surface configuration of a cell [goid 8360] [pmid 10527820] [evidence IDA]; Any process that modulates the surface configuration of a cell [goid 8360] [pmid 7929439] [evidence IDA]; Any process that activates or increases the frequency, rate or extent of vascular endothelial growth factor receptor signaling pathway activity [goid 30949] [pmid 7929439] [evidence IDA]; Any process that activates or increases the frequency, rate or extent of vascular endothelial growth factor receptor signaling pathway activity [goid 30949] [pmid 1312256] [evidence IDA]; Any process that stops, prevents or reduces the frequency, rate or extent of cell death by apoptosis [goid 43066] [pmid 10066377] [evidence IMP]; Any process that stops, prevents or reduces the frequency, rate or extent of cell death by apoptosis [goid 43066] [pmid 11461089] [evidence IMP]; Any process that activates or increases the frequency, rate or extent of the migration of the endothelial cells of blood vessels [goid 43536] [pmid 9202027] [evidence IDA]; The series of molecular signals generated as a consequence of a platelet-derived growth factor receptor binding to one of its physiological ligands [goid 48008] [pmid 17470632] [evidence IDA]; Any process that initiates the directed movement of a motile cell or organism towards a higher concentration in a concentration gradient of a specific chemical [goid 50930] [pmid 12744932] [evidence NAS]