Nuclear differential abundances

Figure 13.8 Examples of differential abundances of nuclear proteins in mitoxantrone-resistant and susceptible cells measured by densitometry and MS (Fu, 2004). a Nucleophosmin, determined to be unchanged and used to correct for the ratio of cells in the mixture.

Terrestrial isotope ratios are mainly unaffected by these processes and therefore provide valid information about standard abundances of individual nuclear species except in special cases where they have been modified by fractionation (e.g. D/H), differential escape from the atmosphere or radioactive decay, e.g. 40Ar is enhanced in the atmosphere relative to 36Ar by 40K decay and there is extra 136Xe thought to result from fission of 244Pu. 

Normal testes expressed only small amounts of /nyc-encoded p62 (S4). Seminomas showed increased nuclear and cytoplasmic staining. Undifferentiated teratomas showed little activity, whereas c-wyc-encoded p62 was abundant in the nuclei of differentiated epithelial structures, yolk sacs, and embryoid bodies. 

Two very different factors are important in determining the abundance patterns shown in Table 1. The overall abundance in the Universe and in the Solar System depends on how elements were made by nuclear reactions. The very different distribution in the Earth and its constituent parts is a consequence of subsequent chemical differentiation of elements during the formation of the planets. 

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