ischemic phase

Examples of ischemic phase in the following topics:

• Ovarian Cycle

  • However, some sources define these phases as menstruation, proliferative phase, and secretory phase.
  • The follicular phase (or proliferative phase) is the phase of the menstrual cycle in humans and great apes during which follicles in the ovary mature, ending with ovulation.
  • The luteal phase (or secretory phase) is the latter part of the menstrual or estrous cycle.
  • The main hormone associated with this stage is progesterone, which is significantly higher during the luteal phase than in other phases of the cycle.
  • Some sources define the end of the luteal phase as a distinct ischemic phase.

• Blood Flow in the Brain

  • In brain tissue, a biochemical cascade known as the ischemic cascade is triggered when the tissue becomes ischemic, potentially resulting in damage to and death of brain cells.

• Interpreting Phase Diagrams

  • The lines that separate these single phase regions are known as phase boundaries.
  • By focusing attention on distinct single phase regions, phase diagrams help us to understand the range over which a particular pure sample of matter exists as a particular phase.
  • When evaluating the phase diagram, it is worth noting that the solid-liquid phase boundary in the phase diagram of most substances has a positive slope.
  • With a knowledge of the major components of phase diagrams and the features of phase plots, a phase diagram can be used to understand how altering thermodynamic parameters influences the states/phases of matter a sample of a substance is in.
  • A typical phase diagram illustrating the major components of a phase diagram as well as the critical point.

• Major Features of a Phase Diagram

  • A phase diagram is a graph which shows under what conditions of temperature and pressure distinct phases of matter occur.
  • The simplest phase diagrams are of pure substances.
  • The major features of a phase diagram are phase boundaries and the triple point.
  • Phase boundaries, or lines of equilibrium, are boundaries that indicate the conditions under which two phases of matter can coexist at equilibrium.
  • In this phase diagram, which is typical of most substances, the solid lines represent the phase boundaries.

• Myocardial Ischemia and Infarction

  • Symptoms of stable ischemic heart disease include angina, which is characteristic chest pain on exertion, and decreased exercise tolerance.
  • The disease process underlying most ischemic heart disease is atherosclerosis of the coronary arteries, which decreases blood flow to the heart muscle.
  • Treatment of ischemic heart disease is dependent on the underlying disease process.
  • This test examines blood flow to the heart during exertion, and can be used as a diagnostic tool in ischemic heart disease, coronary artery disease, and heart failure.
  • In coronary artery disease, these atherosclerotic plaques build up in the coronary arteries and rupture may lead to ischemic heart disease and myocardial infarction.

• Solid to Gas Phase Transition

  • Sublimation is the phase transition from the solid to the gaseous phase, without passing through an intermediate liquid phase.
  • Sublimation is the process of transformation directly from the solid phase to the gaseous phase, without passing through an intermediate liquid phase.
  • It is an endothermic phase transition that occurs at temperatures and pressures below a substance's triple point (the temperature and pressure at which all three phases coexist) in its phase diagram.
  • But at temperatures below that of the triple point, a decrease in pressure will result in a phase transition directly from the solid to the gaseous.
  • At temperatures and pressures below those of the triple point, a phase change between the solid and gas phases can take place.

• Cerebrovascular Accident

  • Risk factors for stroke include old age, hypertension (high blood pressure), previous stroke or transient ischemic attack (TIA), diabetes, high cholesterol, cigarette smoking, and atrial fibrillation.
  • An ischemic stroke is occasionally treated in a hospital with thrombolysis (also known as a "clot buster"), and some hemorrhagic strokes benefit from neurosurgery.
  • Infarcts are more likely to undergo hemorrhagic transformation (leaking of blood into the damaged area) than other types of ischemic stroke.
  • Despite not causing identifiable symptoms, a silent stroke still causes damage to the brain and places the patient at increased risk for both transient ischemic attack and major stroke in the future.

• Transient Ischemic Attacks

  • A transient ischemic attack is similar to a stroke; though without permanent damage, it can serve as an important risk factor for stroke.
  • A transient ischemic attack (abbreviated as TIA, often referred to as mini stroke) is a transient episode of neurologic dysfunction caused by ischemia—either focal brain, spinal cord, or retinal—without acute infarction (tissue death).

• Phase-Contrast Microscopy

  • In phase-contrast microscopy, parallel beams of light are passed through objects of different densities.
  • A phase ring in condenser allows a cylinder of light to pass through it while still in phase.
  • Unaltered light hits the phase ring in the lens and is excluded.
  • Phase-contrast images have a characteristic grey background with light and dark features found across the sample.
  • One disadvantage of phase-contrast microscopy is halo formation called halo-light ring.

• The Evaporating Atmosphere

  • Within each phase, the properties are uniform but between the two phases properties differ.
  • Water in a closed jar with an air space over it forms a two phase system.
  • Even at equilibrium, molecules are constantly in motion and, once in a while, a molecule in the liquid phase gains enough kinetic energy to break away from the liquid phase and enter the gas phase.
  • The water vapor in it changes phases.
  • It is in a phase equilibrium.