stroke

Examples of stroke in the following topics:

• Other Neurological Disorders

  • Epilepsy and stroke are discussed below.
  • Approximately 75 percent of strokes occur in people older than 65.
  • Risk factors for stroke include high blood pressure, diabetes, high cholesterol, and a family history of stroke.
  • Smoking doubles the risk of stroke.
  • Treatment following a stroke can include blood pressure medication (to prevent future strokes) and (sometimes intense) physical therapy.

• ATP and Muscle Contraction

  • As myosin expends the energy, it moves through the "power stroke," pulling the actin filament toward the M-line.
  • At the end of the power stroke, the myosin is in a low-energy position.
  • After the power stroke, ADP is released, but the cross-bridge formed is still in place.

• Blood Pressure

  • The body regulates blood pressure by changes in response to the cardiac output and stroke volume.
  • It is calculated by multiplying the number of heart contractions that occur per minute (heart rate) times the stroke volume (the volume of blood pumped into the aorta per contraction of the left ventricle).
  • However, cardiac output can also be increased by increasing stroke volume, such as if the heart were to contract with greater strength.
  • Stroke volume can also be increased by speeding blood circulation through the body so that more blood enters the heart between contractions.

• Female Hormones

  • Supplementation of estrogen in the form of hormone replacement therapy (HRT) can prevent bone loss, but the therapy can have negative side effects, such as an increased risk of stroke or heart attack, blood clots, breast cancer, ovarian cancer, endometrial cancer, gall bladder disease, and, possibly, dementia.