| MLF | medial longitudinal fascicle |
|---|---|
| OPLL | of the Posterior longitudinal ligament |
| PLL | posterior longitudinal ligament |
| riMLF | rostral intersititial nucleus of the medial longitudinal fasciculus |
| longitudinal pontine bundles | The massive bundles of corticofugal fibres passing longitudinally through the ventral part of pons; they are composed of corticopontine, corticobulbar, and corticospinal fibres. Synonym: fasciculi longitudinales pontis, longitudinal pontine bundles. (05 Mar 2000) |
|---|---|
| longitudinal pontine fasciculi | The massive bundles of corticofugal fibres passing longitudinally through the ventral part of pons; they are composed of corticopontine, corticobulbar, and corticospinal fibres. Synonym: fasciculi longitudinales pontis, longitudinal pontine bundles. (05 Mar 2000) |
| longitudinal relaxation | In nuclear magnetic resonance, the return of the magnetic dipoles of the hydrogen nuclei (magnetization vector) to equilibrium parallel to the magnetic field, after they have been flipped 90 |
| longitudinal section | A section that is cut along the long axis of a structure. The opposite is a cross-section. (12 Dec 1998) |
| longitudinal sinus | See: inferior sagittal sinus, superior sagittal sinus. Longitudinal vertebral venous sinus, large, plexiform veins forming portions of the anterior internal vertebral venous plexus lying on the posterior surfaces of the vertebral bodies on either side of the posterior longitudinal ligament. Synonym: sinus vertebrales longitudinales. Luschka's sinus, venous sinus in the petrosquamous suture. (05 Mar 2000) |
| longitudinal studies | Studies in which variables relating to an individual or group of individuals are assessed over a period of time. (12 Dec 1998) |
| longitudinal study | <epidemiology> A study taking place over time. If individuals are followed, this is a longitudinal cohort study. If individuals are not followed, but classes (usually age classes) are restudied, this is a longitudinal cross-sectional study. The converse of a horizontal study. (05 Dec 1998) |
| longitudinal sulcus of heart | See: anterior interventricular groove, posterior interventricular groove. (05 Mar 2000) |
| longitudinal wave | <physics> Waves where the variation of the field is partially or totally in the direction of propagation (parallel to wavennumber, k [a vector]). Examples include sound waves and Langmuir waves. Contrasted with transverse waves, where the variation is perpendicular to the direction of propagation, such as light waves. (13 Nov 1997) |