transmission (trans-mish´un)

1. transfer 2. The conveyance of disease from one person to another. 3. The passage of a nerve impulse across an anatomic cleft, as in autonomic or central nervous system synapses and at neuromuscular junctions, by activation of a specific chemical mediator that stimulates or inhibits the structure across the synapse. See neurohumoral t. 4. In general, passage of energy through a material. [L. transmissio, a sending across]
duplex t. the passage of impulses in both directions through a nerve trunk.
horizontal t. t. of infectious agents from an infected individual to a susceptible contemporary, in contradistinction to vertical t.
iatrogenic t. t. of infectious agents due to medical interference (e.g., t. by contaminated needles).
neurohumoral t. a process by which a presynaptic cell, upon excitation, releases a specific chemical agent (a neurotransmitter) to cross a synapse to stimulate or inhibit the postsynaptic cell.neurotransmission;
transovarial t. (trans´o-va-re-al) passage of parasites or infective agents from the maternal body to eggs within the ovaries; commonly used to describe certain arthropods, to explain the ability of larvae of the next generation to transmit disease pathogens, as with the infection of larval mites or ticks with rickettsiae or viruses.
transstadial t. passage of a microbial parasite, such as a virus or rickettsia, from one developmental stage (stadium) of the host to its subsequent stage or stages, particularly as seen in mites. See also transovarial t.
vertical t. 1. t. of a virus (e.g., RNA tumor virus) by means of the genetic apparatus of a cell in which the viral genome is integrated; 2. for infectious agents in general, t. of an agent from an individual to its offspring. i.e., from one generation to the next. Cf. horizontal t.


Browse Medical References:

[A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M]
[N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Z]