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Without valves; denoting certain veins (for example, portal) that are not provided with valves as most veins are.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Tabata, "Analysis of valveless piezoelectric micropump using electrical equivalent circuit model," in Proceedings of 4th International Conference on Solid-State Sensors, Actuators and Microsystems, TRANSDUCERS and EUROSENSORS '07, pp.
FMI OEM pumps integrate FMI's unique patented CeramPump valveless pumping principle with precision stepper control.
For example, when we play well-known John Philip Sousa marches, we incorporate valveless regimental trumpets to play the familiar obbligatos in marches such as Semper Fidelis and The Thunderer.
While he has a couple of valveless curiosities of his own hanging around the shop, like a 4-foot Tibetan temple horn, Hansen generally works in the modern age of brass instrumentation dating forward from the 1840s.
The venous hypertension in the valveless cervicofacial system results in the above findings.
The symphony also is performed on period instruments offering the listener the distinct timbres of gut strings, valveless brass, and wooden flutes.
The prior local pooling within valveless, thin-walled epidural veins ruptured following the fluctuations of the pressures.
Colin Furze, who has put together a valveless pulse jet, a propulsion device sometimes used by hobbyists to power model aircraft and other remote-controlled vehicles, is now building a gigantic pair of human buttocks to house his machine, the Verge reported.
Pumps provide a valveless rotating/reciprocation piston design that eliminates the need for check valves, which can clog, leak or fail over time.
For routine uses, the most appropriate sampler seems to be a valveless glass tube that can be sealed with septum caps.
FMI's OEM duplex metering pumps consist of 2 FMI valveless pump heads direct coupled to a single variable stepper motor drive.
By degrees the impact of the electronics was to throw up sounds more or less familiar from Kerbaj's acoustic practice -- valveless aspirations, the squawks of irritable pterodactyls flying overhead -- with new noises.