Radioisotopes techniques

Weygand, F. Studies on Osazones with p-Bromophenylhydrazine labelled with 82Br. Radioisotope Techniques, Vol. I. Her Majesty s Stationary Office, London 1953-... 

In brook trout (Salvelinus fontinalis), feces was the most important egestion route, and spawning was not an important source of chemical elimination of 2,3,7,8-TCDD (Nichols etal. 1998). However, Tietge etal. (1998) disagree and, using radioisotope techniques, show 39% maternal transfer of 2,3,7,8-TCDD to eggs in brook trout, and suggest the need for additional research in this area. 

Overman, R.T. Clark, H.M. (1960). Radioisotope Techniques. McGraw Hill, London. 

Although it is not really a different method, it should be noted that to obtain correlation with service conditions where wear rate is low, very tiny quantities of material lost have to be measured. These small losses may be difficult to measure by the usual weighing or dimensional methods and radioisotope techniques have been used, as for example in the method of Patel and Deviney79. Conceivably, a method for measuring very low levels of wear on a tyre by the change in reflectance of an applied paint80 could be used in laboratory tests. 

C-labelled active plant protection substances for 13 years (17, 18). The results indicate that intensive cooperation between plant protection chemists, phytopathologists, phytophysiologists and specialists in the radioisotope techniques is necessary to fully exploit the application possibilities and to interpret the results. The special experimental facilities at the JUlich Nuclear Research Center which include practically oriented field tests supplemented by detailed studies under defined climatic conditions enable practical and relevant results to be obtained (17-19). The aim of this contribution is to provide new insights and information on the system effectiveness and residue behavior of azole fungicides. 

The spectroscopic techniques described in this section include IR, Raman, and UV-visible spectroscopy, nuclear magnetic resonance (NMR) and electron spin resonance (ESR) spectroscopy, and extended X-ray absorption fine structure (EXAFS) spectroscopy. Techniques based on particle scattering, transitions in the nucleus, and radioisotope techniques that produce radiation that is a measure of the chemical environment are described in Sections IV.B and C. Some of these techniques, such as IR and UV-visible spectroscopy, have been applied to studies of catalysts for more than 30 years, whereas others, such as EXAFS, are relatively new to catalytic studies. 

The spatial and temporal importance of DIP availability in trophic food webs of coastal and estuarine systems has been hinderd by methodology. Simply measuring DIP concentrations alone provides only limited information on how P affects primary production. To borrow once again from the coastal/open ocean literature, new P radioisotope techniques have proven to be a more effective means of understanding P dynamics (Lai and Lee, 1988 Waser et al., 1996 Benitez-Nelson and Buessler, 1999). The two P radioisotopes... 

Any radioisotope decays by one or, at most, only a few nuclear transformation mechanisms. The characteristics of the emitted particles are sufficiently different from one another that the procedures for detection of the different particles must also be different. Therefore, a fundamental knowledge of radioisotope techniques in biochemistry begins with a study of the particles produced during different mechanisms of nuclear transformation. Because the great majority of biochemical applica-... 

A number of other nuclear transformation mechanisms are found in nature, a Particle decay, positron emission, and electron capture events are examples of such nuclear transformations. Techniques have been developed for measuring such decay events. However, the radioisotopic atoms that yield such decay products are used relatively infrequently in biochemistry and biology. If your research requires analysis of such atoms, you should consult a practical textbook in modern physics or radioisotopic techniques. 

Methods for studying zinc bioavailability in humans include metabolic balance studies, radioisotopic techniques, stable isotope techniques, circulating zinc response, and perfusion techniques. These methods of bioavailability, along with other zinc-related studies, also are covered in detail. 

Quantification. Double Radioisotope Technique. In biological samples—W. Riess, Analytica chim. Acta, 1977,88, 109-115. 

R. T. Overman, H. M. Clark, Radioisotope Techniques, McGraw-Hill, New York, 1960 L. C. L. Yuan, C. S. Wu (Eds.), Methods of Experimental Physics, Vol. 5A Nuclear Physics, Academic Press, New York, 1961... 

S. A. Berson and R. S. Yalow, in "Radioisotope Techniques in the Study of Protein Metabolism, p. 29. International Atomic Energy Agency Technical Reports Series No. 45, Vienna, 1965. 

Zambia, Thailand and USA (Florida) were analyzed by using the X-ray fluorescence method for elemental composition. These rock phosphates have also been evaluated for their agronomic effectiveness by means of radioisotope techniques (Zapata and Axmann, 1991). The samples were prepared as pellets and analyzed using the emission transmission method for trace elements (Markowicz and Haselberger, 1992). All samples were excited using an Mo tube with an Mo secondary target. For quality control of concentration data analysis of standard reference material CRM 032 (phosphate rock) produced by CEC, Brussels, has been used. Satisfactory agreement between certified and measured values was obtained. 

Whole body selenium is about 15 mg, as estimated by direct tissue analysis and radioisotope techniques, with the tissue concentration of selenium being highest in the kidney and the liver followed by the other organs. Radioisotope-labeled selenium accumulates initially in the liver, kidneys, and lungs. Selenium present in some selenocysteine proteins appears to be a functional reserve. When dietary selenium is limited, synthesis of glutathione peroxidase (GSHP)x-l is... 

Radioisotope techniques have allowed precise measurement of dietary iron absorption. Initial studies utilized test meals of individual food which had been intrinsically labeled with radios active iron prior to harvesting (1,2). Utilization of these single food meals allowed a rank order to be established among the tested foods. Subjects could serve as their own controls when an identical reference dose was given to each subject. 

R.L. Leibel and J. Hirsch, A radioisotopic technique for analysis of free fatty acid reesterification in human adipose tissue, Am.J. Physiol., 1985, 248, 140-147. 

Measurement of the GFR is ideally performed using the exogenous administration of inulin, iothalamate, or radioisotope techniques such as "Tc-DTPA. 

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