Kidney ultrasound. Also called: renal ultrasound. A kidney ultrasound is used to determine the size, shape and location of the kidneys without cutting the skin. A kidney ultrasound makes it possible to see the kidneys from outside the body by using ultrasonic waves.
An early recognized function of astrocytes is the control of K + levels in the brain. Neuronal activity leads to an increase in K + concentration from a resting level of about 3 mM to a maximum of 10 - 12 mM under physiological conditions and to even higher values under pathological conditions.strocytes may also limit the number of synapses since astrocyte membranes can ensheath the neuronal processes and thus compete with synapses. Astroglial cells can also be involved in the elimination of synapses in the CNS, the process which underlies the final tuning and plasticity of the neuronal inputs.
Astrocytomas are a type of cancer of the brain. They originate in a particular kind of glial cells, star-shaped brain cells in the cerebrum called astrocytes. This type of tumor does not usually spread outside the brain and spinal cord and it does not usually affect other organs.