The angioarchitecture of the XXXX in laboratory @entity19 (a light microscopic and scanning electron microscopic study).

@entity19 @entity2 @entity5 @entity39
53 @entity2 implanted subcutaneously into C57BL/6- @entity19 were examined. The animals were killed at various stages of @entity5 ( @entity5 ) and prepared for histology and for scanning electron microscopy (critical-point-dried tissue; vascular corrosion casts). Prior to casting animals were rinsed using different perfusion pressures. Casting was done by manual injection of the resin, whereby different influx-rates were applied resulting in low, medium and high pressure preparations. We discern 3 phases of @entity5 angiogenesis (TA) occurring during 4 stages of @entity5 among which vasodilation establishes the first reaction of the host vascular system to a growing @entity5 implant. During this stage 1 of @entity5 , @entity5 nidation, nearby sinusoidal dilated host capillaries form globular outgrowings (phase 1 of TA). Subsequently radially arranged sprouts, which preferentially arise from venous host vessels, grow into the centre of the implant (phase 2 of TA). Stage 2 of @entity5 , early @entity5 , is characterized by @entity39 tissue and the development of a central avascular cavity. Thus the @entity5 vascular system is organized like a hollow sphere with a central cavity and a peripheral vascular "envelope" with large vessels embracing the @entity5 and centrifugally growing vascular sprouts, which arise from the venous part of the vascular "envelope" and invade the surrounding host tissue (phase 3 of TA). During stage 3 of @entity5 , late @entity5 , many vessels of the basket-like vascular "envelope" obliterate. In stage 4 of @entity5 , prefinal phase, the peripheral vascular density decreases continuously. Thus vascular sprouting and proliferation of viable @entity5 cells is confined to basal regions of the @entity5 .
