Search results for "Flow"

nrCBF for Timing of Angiography and Operation in Subarachnoid Hemorrhage

1983

Early operation on cerebral aneurysms is demanded not least because of the threat of spasm of the cerebral vessels. As is generally recognized, this is to be expected in a very high percentage within a few days after the first aneurysm hemorrhage and frequently cannot be diagnosed clinically (4, 5). Many neurosurgeons have rated the risk of operating in the presence of vasospasm so high that, like C.G. DRAKE in 1975 (2), they demanded control angiography with its own risk, especially in existing vasospasm in early angiography and the aneurysm operation itself could not take place rapidly.

Transmission of arterial oxygen partial pressure oscillations to the cerebral microcirculation in a porcine model of acute lung injury caused by cycl…

2013

Cyclic recruitment and derecruitment (R/D) play a key role in the pathomechanism of acute lung injury (ALI) leading to respiration-dependent oscillations of arterial partial pressure of oxygen (Pa(O(2))). These Pa(O(2)) oscillations could also be forwarded to the cerebral microcirculation.In 12 pigs, partial pressure of oxygen was measured in the thoracic aorta (Pa(O(2))) and subcortical cerebral tissue (Pbr(O(2))). Cerebral cortical haemoglobin oxygen saturation (Sbr(O(2))), cerebral blood flow (CBF), and peripheral haemoglobin saturation (Sp(O(2))) were assessed by spectroscopy and laser Doppler flowmetry. Measurements at different fractions of inspired oxygen (F(I(O(2)))) were performed …

Umbilical artery blood flow velocity waveforms during variable decelerations of the fetal heart rate

1991

Blood flow velocities of the umbilical arteries were measured by Doppler ultrasonography during variable decelerations of the fetal heart rate. The flow velocity waveforms, being normal between uterine contractions, showed either an unchanged flow velocity waveform with an exclusive fetal heart rate effect on end-diastolic velocities or a rapid change to absent and reverse diastolic flow during the decelerations, indicating an abrupt increase in placental resistance with a halt in placental perfusion. Computer-aided reconstruction of the fetal heart rate curve revealed the exact temporal relationship between the reduction of umbilical artery perfusion and deceleration of fetal heart rate. W…

Pedobarography: A Review on Methods and Practical Use in Foot Disorders

2021

Pedobarographic examination is a non-invasive method that enables the quantitative and qualitative evaluation of plantar pressure distribution, notably the plantar pressure distribution, referring to the function of the entire musculoskeletal system. This is a scoping review that aims to update knowledge on the practical use of pedobarography in foot disorders. We also attempted to systematize the methodological principles of conducting the pedobarographic examination. We searched Medline/PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews for the articles on the methodology of pedobarography. The search encompassed clinical trials, randomized controlled trials, …

Modification of Angular Kinematics and Spatiotemporal Parameters during Running after Central and Peripheral Fatigue

2021

Fatigue causes kinematics modifications during running, and it could be related to injuries. The aim was to identify and compare the effects of central and peripheral fatigue on angular kinematics and spatiotemporal parameters during running. Angular kinematics and spatiotemporal parameters were evaluated using an infrared motion capture system and were registered during 2 min treadmill running in pre- and post-fatigue states in eighteen male recreational runners. Central fatigue was induced by a 30 min running fatigue protocol on a treadmill, while peripheral fatigue in quadriceps and hamstrings muscles was induced by an isokinetic dynamometer fatigue protocol. Central fatigue increased th…

Cerebral protection against ischemia by locomotor activity in gerbils. Underlying mechanisms.

1995

Background and Purpose A previous communication of this laboratory demonstrated reduced mortality and neuronal damage by spontaneous locomotor activity preceding forebrain ischemia in Mongolian gerbils. The present experiments seek to elucidate potential mechanisms of protection by measurement of cerebral blood flow, cerebral tissue conductance as an indicator of ischemic cell swelling, and the cerebral release of eicosanoids. Methods Gerbils were maintained either in conventional cages (nonrunners) or with free access to running wheels (runners) for 2 weeks preceding 15 minutes of forebrain ischemia. During ischemia and 2.5 hours of reperfusion, cerebral tissue conductance was determined …

Regional cerebral blood flow (rCBF) changes following local brain compression in the cat.

1968

Absorption of protein in the early postoperative period in chronic conscious dogs.

1988

Postoperative alterations in amino acid exchange across the intestinal tract and in the capacity for protein absorption were investigated in a chronic canine model. Changes in postoperative splanchnic amino acid exchange consisted of a temporary decrease of total splanchnic amino acid release, including a significant reduction in alanine production, and an increase in glutamine consumption. Contrary to results under stable metabolic conditions, branched chain amino acids were also taken up by the intestine in the early postoperative period. The changes in postoperative amino acid exchange were not, however, reflected by a corresponding alteration in protein transport capacity. The absorptiv…

Lipoic Acid Improves Nerve Blood Flow, Reduces Oxidative Stress, and Improves Distal Nerve Conduction in Experimental Diabetic Neuropathy

1995

OBJECTIVE To determine whether lipoic acid (LA) will reduce oxidative stress in diabetic peripheral nerves and improve neuropathy. RESEARCH DESIGN AND METHODS We used the model of streptozotocin-induced diabetic neuropathy (SDN) and evaluated the efficacy of LA supplementation in improving nerve blood flow (NBF), electrophysiology, and indexes of oxidative stress in peripheral nerves affected by SDN, at 1 month after onset of diabetes and in age-matched control rats. LA, in doses of 20, 50, and 100 mg/kg, was administered intraperitoneally five times per week after onset of diabetes. RESULTS NBF in SDN was reduced by 50% LA did not affect the NBF of normal nerves but improved that of SDN i…

Influence of the terminal complement-complex on reperfusion injury, no-reflow and arrhythmias: a comparison between C6-competent and C6-deficient rab…

1996

Objective: The complement system has been suggested to play a role in reperfusion injury which may result from an enhanced destruction of myocardial tissue or from an impairment of reflow. We investigated the influence of the C5b-9 complement complex on infarct size, reflow and arrhythmogenesis. Methods: Twenty-eight C6-competent rabbits and 18 rabbits with congenital C6 deficiency were subjected to either 30 min or 2 h of coronary artery occlusion followed by reperfusion. C6 deficiency was confirmed by the complement titration test and immunohistology. The triphenyl tetrazolium chloride method was used to delineate infarct size. Reflow into infarcted areas was evaluated histologically afte…