| modulation | Alteration in the effectiveness of voltage gated or ligand gated ion channels by changing the characteristics of current flow through the channels. The mechanism is thought to involve second messenger systems. (18 Nov 1997) |
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| modulation transfer function | <microscopy> A mathematical function that expresses the ability of an optical or electronic device to transfer signals faithfully as a function of the spatial or temporal frequency of the signal. The modulation transfer function is the ratio of percentage modulation of a sinusoidal signal leaving to that entering the device over the range of frequencies of interest. The modulation transfer function is usually presented as a graph of modulation transfer function versus log (frequency). For a square wave signal, the function is known as the CTF. Acronym: MTF (26 Mar 1998) |
| antigenic modulation | Loss of detectable antigen from the surface of a cell after incubation with antibodies. This is one method in which some tumours escape detection by the immune system. Antigenic modulation of target antigens also reduces the therapeutic effectiveness of treatment by monoclonal antibodies. (12 Dec 1998) |
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