Probe agents

Nordmark A, Lundgren S, Cnattingius S et al. (1999) Dietary caffeine as a probe agent for assessment of cytochrome P4501A2 activity in random urine samples. Br J Clin Pharmacol 47 397-402... 

Nieves, J.W., J.A. Grisso, and J.L. Kelsey. 1992. A case-control study of hip fracture Evaluation of selected dietary variables and teenage physical activity. Osteoporosis Int. 2(3) 122-127. Noordzij, M., C. Uiterwaal, L.R. Arends, et al. 2005. Blood pressure response to chronic intake of coffee and caffeine A meta-anal-ysis of randomized controlled trials. J. Hyperten. 23(5) 921-928. Nordmark, A., S. Lundgren, S. Cnattingius, and A. Rane. 1999. Dietary caffeine as a probe agent for assessment of cytochrome P4501A2 activity in random urine samples. Br. J. Clin. Pharmacol. 47(4) 397-402. 

What metals are used as probe agents in biological systems ... 

P. Anilkumar and M. Jayakannan, Fluorescent tagged probing agent and structure-directing amphiphilic molecular design for polyaniline nanomaterials via seU-assemhly process, J. Phys. Chem. C, 111, 3591-3600 (2007). 

Iron(II) ediylenediaminetetraacetic acid [15651 -72-6] Fe(EDTA) or A/,Ar-l,2-ethaiiediylbis[A[-(carboxymethyl)glyciQato]ferrate(2—), is a colorless, air-sensitive anion. It is a good reducing agent, having E° = —0.1171, and has been used as a probe of outer sphere electron-transfer mechanisms. It can be prepared by addition of an equivalent amount of the disodium salt, Na2H2EDTA, to a solution of iron(II) in hydrochloric acid. Diammonium [56174-59-5] and disodium [14729-89-6] salts of Fe(EDTA) 2— are known. 

An experimental problem is to obtain adequate dispersion of the particles before sedimentation analysis. For powders that are difficult to disperse the addition of dispersing agents is necessary, together with mtrasonic probing. It is essential to examine a saiTmle of the dispersion under a microscope to ensure that the sample is fully dispersed. 

The parent indolo[2,3-fl]carbazole (1) has also been the subject of a study probing its reactivity toward oxidizing agents. One of the substrates involved, namely 85 (prepared from 1 and 2,5-dimethoxytetrahydrofuran in the presence of acid), was subjected to treatment with m-chloroperbenzoic acid, to give the dione 86 as the major product and a sensitive compound assigned the hydroxy structure 87. A cleaner reaction took place when 85 underwent oxidation with tert-butyl hydroperoxide assisted by VO(acac)2, to produce 86 exclusively in 86% yield. Likewise, A,N -dimethylindolo[2,3-fl]carbazole furnished the dione 88 on treatment with this combination of reagents (96J(X 413). 

Vulkanisatjons-mittel, n. vulcanizing agent, -probe, /. vulcanizing test or sample, -ver-zdgerung, /. retardation vulcanization. 

Most disease-specific molecular and cellular processes involve low concentrations and have low capacities. Therefore, molecular imaging requires highly sensitive imaging modalities to detect and quantify the imaging probes as it is done with short-lived radioisotopes. Optical imaging and ultrasound are next in sensitivity. MRI would require too high contrast agent concentrations... 

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