<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Clemens, T L</style></author><author><style face="normal" font="default" size="100%">Adams, J S</style></author><author><style face="normal" font="default" size="100%">Henderson, S L</style></author><author><style face="normal" font="default" size="100%">Holick, M F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Increased skin pigment reduces the capacity of skin to synthesise vitamin D3.</style></title><secondary-title><style face="normal" font="default" size="100%">Lancet</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Lancet</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">African Continental Ancestry Group</style></keyword><keyword><style  face="normal" font="default" size="100%">Cholecalciferol</style></keyword><keyword><style  face="normal" font="default" size="100%">European Continental Ancestry Group</style></keyword><keyword><style  face="normal" font="default" size="100%">Humans</style></keyword><keyword><style  face="normal" font="default" size="100%">Melanins</style></keyword><keyword><style  face="normal" font="default" size="100%">Radiation Dosage</style></keyword><keyword><style  face="normal" font="default" size="100%">Rickets</style></keyword><keyword><style  face="normal" font="default" size="100%">Skin</style></keyword><keyword><style  face="normal" font="default" size="100%">Skin Pigmentation</style></keyword><keyword><style  face="normal" font="default" size="100%">Ultraviolet Rays</style></keyword><keyword><style  face="normal" font="default" size="100%">Ultraviolet Therapy</style></keyword><keyword><style  face="normal" font="default" size="100%">vitamin D</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1982</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1982 Jan 9</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">1</style></volume><pages><style face="normal" font="default" size="100%">74-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;To determine the effect of increased skin pigment on the cutaneous production of vitamin D3, circulating vitamin D concentrations were determined in two lightly pigmented Caucasian and three heavily pigmented Negro volunteers after exposure to a single standard dose of ultraviolet radiation (UVR). Exposure of Caucasian subjects to 1 minimal erythemal dose of UVR greatly increased serum vitamin-D concentrations by up to 60-fold 24-48 h after exposure, whereas this dose did not significantly change serum vitamin-D concentrations in Negro subjects. Re-exposure of one Negro subject to a dose of UVR six times larger than the standard dose increased circulating vitamin D to concentrations similar to those recorded in Caucasian subjects after exposure to the lower dose. These results indicate that increased skin pigment can greatly reduce the UVR-mediated synthesis of vitamin D.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">8263</style></issue><custom1><style face="normal" font="default" size="100%">&lt;p&gt;http://www.ncbi.nlm.nih.gov/pubmed/6119494?dopt=Abstract&lt;/p&gt;
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