Human metabolism

Crespi, C.L. (1995) Xenobiotic-metabolizing human cells as tools for pharmacological and toxicological research, in Advances in Drug Research (eds U.A. Meyer and B. Testa), Academic Press, New York, pp. 179-235. 

Xenobiotic-metabolizing Human Cells as Tools for Pharmacological and Toxicological Research... 

XENOBIOTIC-METABOLIZING HUMAN CELLS AS RESEARCH TOOLS 181... 

Xenobiotic metabolism by brain monooxygenases and other cerebral enzymes, 13, 95 Xenobiotic-metabolizing human cells as tools for pharmacological research, 26,179... 

The retinal receptors have a very active metabolism. Human rod cells (Fig. 23-40) may live and function for a hundred years.190 A self-renewal process leads to a casting off of the older membranous discs from the end of the rod194 and replacement by new discs at the end nearest to the nucleus. The rod outer segment is surrounded by a plasma membrane. Within the membrane but apparently not attached to it are -500 stacked discs of -2 pm diameter and with a repeat distance between centers of -32 nm. Each disc is enclosed by a pair of membranes each - 7 nm thick with a very narrow space between them. From electron micrographs it appears that this space within the discs is sealed off at the edges. Somewhat larger spaces separate adjacent discs. 

McGinnity DF, Griffin SJ, Moody GC, et al. Rapid characterization of the major dmg-metabolizing human hepatic cytochrome P-450 enzymes expressed in Escherichia coli. Dmg Metab Dispos 1999 27 1017-1023. 

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