Oxygen isotope variation maybe results from crystallization, degasification or hybridization of crust materials.

Ursodeoxycholic acid is a kind of hydrophilic bile acid. It can hinder hydrophobic bile acid from its hepatotoxicity to liver and the damage of cytotoxic t lymphocyte (CTL) to its target cells.

Objective To evaluate the clinical application value of the tauro ursodeoxycholic acid (TUDCA) for preventing the relapse of lithiasis after the gallbladder-protected lithotomy.