Plasma monitoring

Preskorn, S.H., Weller, E., Hughes, C., and Weller, R. (1986) Plasma monitoring of tricyclic antidepressants defining the therapeutic range for imipramine in depressed children. Clin Neuropharma-col 9 265-267. 

None of these augmentation strategies is ideal, since they either require plasma monitoring (lithium, tryptophan, tri-iodothyronine), expose the patient to potential toxicity (lithium, tryptophan) or have only a moderate evidence base for efficacy (triiodothyronine, pindolol). 

Many biochemistry laboratories no longer undertake routine measurement of the plasma concentration for most anticonvulsant drugs because plasma concentrations are insufficiently stable to serve as a useful guide to change of dose. The exception is phenytoin, where a small increase in dose may lead to a disproportionate rise in the plasma drug concentration (see zero-order pharmacokinetics, p. 99) and plasma monitoring is essential. With other drugs the dose is increased to the maximum tolerated level and, if seizures continue, it is replaced by another. 

Progress in plasma monitoring with advanced methods of atomic, molecular, and optical physics, as exemplified above, has contributed greatly to plasmaprocessing technology, especially in improving the reproducibility of a treatment procedure. 

Yet another problem may be encountered in the treatment of patients in whom severe renal damage has developed prior to correct diagnosis, and applies too in both uric acid and 2,8-DHA stone formers. Here the allopurinol dose must be reduced because oxipuri-nol, the active metabolite in vivo, is reabsorbed by the kidney and retained in excess in renal failure. The effective circulating levels are thus higher and the dose must be reduced accordingly, and oxipurinol levels in plasma monitored if possible,with the dose adjusted to keep circulating levels below 100 /xmol/litre (14). Oxipurinol will not only potentiate the action of immunosuppressive drugs such as azathioprine but can itself produce severe bone marrow depression (14). 

C-reactive protein Plasma Monitoring response to anti-inflammatory therapy... 

Figure 10 Metabolism of leu-enkephalin in plasma monitored by copper complexation and CEEC (A) plasma blank, (B) t = 30 min, (C) i = 60 min, (D) r = 90 min. Peak identification (1) tyrosine, (2) leu-enkephalin, (3) des-tyr leu-enkephalin. (Modified with permission from Ref. 60.)...

The Philae lander carries ten scientific instruments panoramic, stereoscopic and descent camera a-p-x-ray spectrometer evolved gas analyser for elemental, molecular and isotopic composition infrared microscope comet acoustic surface and sounding experiment permittivity probe dust impact monitor multi-purpose sensor for surface and sub-surface science magnetometer plasma monitor comet nucleus sounding experiment drill and sample distribution system. 

Plasma monitors have pixel compartments that contain xenon and neon gas. Each pixel consists of three subpixels one containing a red phosphor, one with a green phosphor, and one with a blue phosphor. Two perpendicular sets of electrodes define a matrix around the subpixels ... 

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