Glossary

Author: Glossary

  • Sympathetic trunk

    Either of two long chains of paravertebral sympathetic ganglia, connected by sympathetic nerve fibers, and extending along the vertebral column from the skull to the coccyx.  

  • Pulmonary trunk

    The great vessel that arises from the right ventricle of the heart and gives rise to the right and left pulmonary arteries to the lungs.  

  • Lumbosacral trunk

    Part of the fourth and all of the fifth lumbar spinal nerves. These nerves accompany part of the first, second, and third sacral nerves to form the sciatic nerve.  

  • Troy weight

    A system of weighing gold, silver, precious metals, and jewels in which 5760 gr equal 1 lb; 1 gr equals 0.0648 g.  

  • Trousseau’s spots

    Streaking of the skin with the fingernail, seen in meningitis and other cerebral diseases.  

  • Synaptic trough

    The depression in a muscle fiber adjacent to the axon terminal of a motor neuron in a myoneural junction.  

  • Focal trough

    A three-dimensional area within which structures are accurately reproduced on a panoramic radiograph. Positioning the patient within the focal trough is critical to producing a panoramic radiograph that clearly reproduces oral structures.  

  • Arm trough

    A concave positioning device attached to a wheelchair armrest that positions the arm and prevents lateral leaning, thus encouraging postural alignment.  

  • Trotter’s syndrome

    A unilateral neuralgia in the mandible, tongue, and ear. The causes are mandibular nerve lesions, deafness on the same side due to eustachian tube lesions, and damage to the levator palatini muscle resulting in kinesthesia of the soft palate.  

  • Tropomyosin

    An inhibitory protein in muscle fibers; it blocks myosin from forming cross-bridges with actin until shifted by troponin-calcium ion interaction.