The following links discuss reports by some strict creationists that relatively fresh or intact blood cells have been found in dinosaur fossils, supposedly disproving conventional geology and supporting a young earth. These claims sprang from work on T.rex bones by paleontologist Mary Schweitzer. Interestingly, Schweitzer (by her own description) is an evangelical Christian, but does not see her work as supporting young earthism or refuting evolution. In fact, she has reportedly been dismayed by strict creationists not accurately reporting her work and conclusions. According to Barry Yeoman who interviewed her for an article in Discover, " Unlike many creationists, she finds the notion of a world evolving over billions of years theologically exhilarating." He quoted Schweitzer as saying "That makes God a lot bigger than thinking of Him as a magician that pulled everything out in one fell swoop." (Discover, Vol. 27, April 2006).
In July 2008 dinosaur researcher Tom Kaye et. al. published a paper providing strong evidence that the supposed soft tissues and vascular structures were actually "biofilms" produced by bacteria, or in the case of supposed blood cells, noncellular structures cammed framboids. When framboids are coated with biofilm, they can even resemble nucleated reb blood cells under a light microscope. Kaye's work appears to undermine creationists claims that "soft tissue" preservation is definite, and that it supports a young earth.
Kaye TG, Gaugler G, Sawlowicz Z (2008), Dinosaurian Soft Tissues Interpreted as Bacterial Biofilms. PLoS ONE 3(7)