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Without valves; denoting certain veins (for example, portal) that are not provided with valves as most veins are.
References in periodicals archive ?
Two plastic surgeons on the panel agreed that the PIP/USA implant, a valveless, pre-filled implant, had advantages, including a shorter surgical time and a potential for less leakage.
The soloist uses the valveless, 'Baroque trumpet' which is seven feet, six inches long and this allows him to give us the full brilliance and sparkling ornamentations originally intended by the composers.
The unique sound of the period instruments, the gut strings, the valveless brass and the wooden flutes was immediately apparent.
Pumps provide a valveless rotating / reciprocation piston design that eliminates the need for check valves, which can clog, rleak or fail over time.
The 1500-1L Benchtop utilizes the Valveless Expansion Technology(VET) also developed by Apeks.
Invited guests also enjoyed a tour of the museum's top ten treasures including the David Brown's Valveless Car and the Skelmanthorpe flag.
The IDS-2000ARH Industrial Dispense Pump has a valveless design with only one moving part, a single rotating and reciprocating piston made of dimensionally stable, chemically resistant ceramics.
It is hypothesized that the valveless vertebral venous plexus allows the tumour emboli to bypass the pulmonary filter and enter the cranial areas.
The vertebral venous plexus is a valveless system which communicates directly with pelvic, sacral, intercostal, azygos, caval and intracranial veins (1).
Solid-state electronics, stepping-motor drives, and valveless ceramic pumps reportedly provide accuracy, reliability, and long life.
4) Nelson et al suggested that the Valsalva maneuver may cause a retrograde flow through a thin valveless low-pressure system that communicates with the venous system of the thorax, abdomen, and pelvis; through this pathway, tumor emboli are transported to the pterygoid plexus and paranasal sinuses.