The behavior of cerebral blood flow and oxygenation during prolonged brain activation was studied using magnetic resonance imaging (MRI) sensitized to flow and oxygenation changes, as well as positron emission tomography sensitized to flow. Neuronal habituation effects and hemodynamic changes were evaluated across tasks and cortical regions. Nine types of activation stimuli or tasks, including ...

Background: Ischaemic reperfusion injury (IRI) after tourniquet release during total knee arthroplasty (TKR) is related to postoperative cerebral complications. Remote ischaemic preconditioning (RIPC) is known to minimise IRI in previous studies. Thus, we evaluated the effect of RIPC on regional cerebral oxygenation after tourniquet release during TKR. Methods: Patients undergoing TKR were rand...

BACKGROUND AND OBJECTIVE Ozone therapy is being used to treat ischemic disorders. However, the underlying mechanisms for the success are unknown and the therapy has not been accepted fully within conventional medicine. This study sought to assess the effect of ozone therapy on resting muscle oxygenation. PATIENTS AND DESIGN Twenty-three (23) patients and 3 volunteers were recruited for this p...

Functional magnetic resonance imaging is widely used to map patterns of brain activation based on blood oxygenation level dependent (BOLD) signal changes associated with changes in neural activity. However, because oxygenation changes depend on the relative changes in cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO(2)), a quantitative interpretation of BOLD signals, and al...

BACKGROUND Hypoxia and hypoxemia are among the most common complications of endotracheal suctioning. These complications are often mitigated by the administration of oxygen 100% prior to endotracheal suction. Although several studies have supported the application of this method, none have yet specified the exact duration of pre-oxygenation required to be performed before endotracheal suction. ...

Oxygenation and thermochemical post-growth treatments of top seeded melt-growth (TSMG) YBCO bulk superconductors can significantly influence critical current density. It is shown that, depending on oxygenation conditions and the size of 211 particles, different reductions of intrinsic critical current density values can be obtained due to the reduction in the sample cross-section caused by the ...

Abstract There are current debates around the extent of global ocean oxygenation, particularly from late Neoproterozoic to early Paleozoic, based on analyses various geochemical indices. We present a temporal trend in excess barium (Baexcess) contents marine organic-rich mudrocks (ORMs) provide an independent constraint redox evolution. The absence remarkable Baexcess enrichments Precambrian (&...