Results 211 to 220 of about 140,558 (264)

Decorrelation-based blood flow velocity estimation: effect of spread of flow velocity, linear flow velocity gradients, and parabolic flow

IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2002
In recent years, a new method to measure transverse blood flow, based on the decorrelation of the radio frequency (RF) signals has been developed. In this paper, we investigated the influence of nonuniform flow on the velocity estimation. The decorrelation characteristics of transverse blood flow using an intravascular ultrasound (IVUS) array catheter ...
A F W Van Der Steen, Frits Mastik, Chris L de Korte   +2 more
exaly   +5 more sources

Effects of blood donation on cerebral blood flow velocity

Transfusion, 1990
Eighteen healthy male blood donors, nine with hematocrit (Hct) of 0.40 to 0.45 (normal Hct) and nine with Hct of 0.49 to 0.52 (upper‐limit Hct), were monitored by continuous‐wave internal carotid Doppler sonography and hematologic tests for 28 days after blood donation, to ascertain whether and to what extent a single standard donation may modify the ...
Silvani C, Zanella A, Rossi F, Cabrini G, Ferrari C, CESANA, Bruno Mario, Sirchia G.   +6 more
openaire   +3 more sources

Estimating Blood Flow Velocity in Liver Vessels

2009
Orthogonal polarization spectroscopy (OPS) is a technique for taking images to finally characterise microcirculation. Current image analysis algorithms have limitations when applied to image sequences obtained from the liver. We developed an automatic analysis tool which enables detection of liver vessels, measurement of vessel diameters, and ...
Müller, Michael, Keimling, René, Lang, Sascha, Pauli, Josef, Dahmen, Uta, Dirsch, Olaf   +5 more
openaire   +1 more source

Blood flow velocities in human intraplacental arteries

Acta Obstetricia et Gynecologica Scandinavica, 1994
Objective. To characterise the physiological findings of blood circulation in intraplacental arteries in normal and complicated pregnancies.Design. A descriptive cross‐sectional study. Umbilical and intraplacental artery resistance index (RI) Doppler recordings during the last trimester of pregnancy.Subjects.
P, Kirkinen, J, Kurmanavichius, A, Huch, R, Huch   +3 more
openaire   +2 more sources

Effect of Adenosine on Cerebral Blood Flow Velocity

Journal of Neuroimaging, 2001
ABSTRACTBackground and Purpose. Evidence suggests that adenosine (ADN) is a potent vasodilator of cerebral vessels. However, the feasibility of manipulating human cerebral vascular resistance with AND has not been assessed by means of TCD. The purpose of this study was to quantitatively estimate the change in middle cerebral artery cerebral blood flow ...
C, Zanferrari, A Y, Razumovsky, P M, Lavados, S, Sen, S M, Oppenheimer   +4 more
openaire   +2 more sources

Blood flow velocity in pulmonary microvessels of bullfrog

Respiration Physiology, 1979
Flow velocity in the pulmonary microvessels of the exposed lung of bullfrogs was measured by means of a laser Doppler microscope of an oblique backward mode, together with a signal-analyzing system having a time sharing circuit triggered by the R-wave of the ECG.
M, Horimoto, T, Koyama, H, Mishina, T, Asakura, M, Murao   +4 more
openaire   +2 more sources

Effect of Pentoxifylline on Microvascular Blood Flow Velocity

Angiology, 1981
Pentoxifylline (PF), known to increase red blood cell (RBC) deformability, has recently attracted much attention because of its possible effect of reducing capillary resistance. There has been practically no reliable demonstration of an increase in capillary blood flow by this drug.
N, Ohshima, M, Sato
openaire   +2 more sources

Retinal blood flow velocity in metabolic syndrome

Graefe's Archive for Clinical and Experimental Ophthalmology, 2013
Metabolic syndrome (MetS) is characterized by obesity, insulin resistance, dyslipidemia, and hypertension. The Retinal Function Imager (RFI) is a new technique for measuring retinal blood-flow velocity. This study aims to compare retinal blood flow velocity between MetS and healthy subjects.Twenty eyes of 20 MetS males and 21 eyes of 21 aged-matched ...
Shay, Gutfreund, Elena, Izkhakov, Russell, Pokroy, Marianna, Yaron, Hanny, Yeshua, Zvia, Burgansky-Eliash, Adiel, Barak, Ardon, Rubinstein   +7 more
openaire   +2 more sources