# I am the Watcher. I am your guide through this vast new twtiverse.
#
# Usage:
# https://watcher.sour.is/api/plain/users View list of users and latest twt date.
# https://watcher.sour.is/api/plain/twt View all twts.
# https://watcher.sour.is/api/plain/mentions?uri=:uri View all mentions for uri.
# https://watcher.sour.is/api/plain/conv/:hash View all twts for a conversation subject.
#
# Options:
# uri Filter to show a specific users twts.
# offset Start index for quey.
# limit Count of items to return (going back in time).
#
# twt range = 1 1
# self = https://watcher.sour.is/conv/muxoyfa
每天都涂防晒，会不会防晒过度，影响身体维生素 D 合成，导致骨质疏松呢？**
谢谢彭工 @配方师Markgo ，这题我会，在书本上啃到过。
开明综义，确实会有影响。
维生素D是各种维生素中的另类，它是在皮肤里合成的。说具体点，是在表皮的棘层和基底层。
原料是7-脱氢胆固醇，在紫外线的作用下6号电子发生顺旋电环化反应，形成前维生素D3。
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