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Beneficial
is defined by the self, the same entity the exerts the influence and the same
entity whose behavior is the object of influence. This circular,
self-reference is the basis of the emergence of consciousness - or
certainly a new level of complexity of biological creatures.
Richard Hofsteadter brilliantly describes this view of experience and reality
in his book: Godel Escher and Bach. It is a hard read, but can be
great fun. Back to home page
- Up and Down Regulation
Down-regulation - when excessive numbers of transmitter
molecules are available to the receptor over a period of time, a decrease in
the receptor sites can be counted. This is called down-regulation. It accounts
for tolerance e.g., when heroine consistently occupies opiod binding sites.
The desensitized post-synaptic neuron will not respond to average amounts of
heroine, but increased amounts are required to obtain and opiod effect. This
in turn induces greater levels of tolerance.
Up-regulation - the reverse occurs when decreased number of
transmitter molecules are available at post-synaptic receptors. This
leads to up-regulation with increased number of sensitized receptors. Such a
condition would occur during a receptor blockade. e.g., the anti-psychotic
medication thorazine bocks the dopamine receptor inducing up-regulation. As a
result, additional dopamine receptors appear on the post-synaptic membrane. At
this point the post-synaptic neuron is hypersensitive, and if the blockade is
ended, even average amounts of dopamine can cause the movement disorder:
Tardive Dyskinesia. This
condition may be treated by administration of dopamine agonists or by
reestablishing the dopamine blockade.
Back to biology.
- Iatrogenic Conditions refer to
pathological conditions caused by the treatment of
a physician or treatment provider.
For
example: On the 16th day in November in 1906,
Robert Strong Pearson inoculated 24 men - inmates at of the Bilibid prison in
Manilla - with an experimental
cholera
vaccine that had become contaminated with plague organisms. All recipients of
the vaccine fell ill and 13 died. None would have become
ill had they not encountered Dr. Pearson. Back to
the Imp
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