Examples include the coagulation factors VII, IX and X, protein C and its cofactor protein S.

Her television roles include Xena: Warrior Princess, Once a Thief, Cleopatra 2525, Mutant X, and Day Break.

Famous covered songs include X Japan's ex-member, hide's, solo song Pink Spider and Shizuka Kudō's Blue Velvet.

(Note that if we use the nullary intersection convention, then there is no need to include X in the second definition.)

These include X, J or G, C (hard) or K, C (soft) or S, and Q.

Guests include Blondie's Debbie Harry and Chris Stein, plus X Factor's Stacey Solomon.

Yes - but how many times, in reviewing a book myself, have I wanted to ask the author something: why did you include X and ignore Y?

Her television credits include Mutant X, Relic Hunter,Falcon Beach and The Dresden Files.

Models include Zero, Light Action, and X for road cycling, Frog for mountain biking, and Drillium for downhill.

Prominent Men in Black agents included X, Alex Krycek, the Crew Cut Man, and Quiet Willy.