After I downloaded the update to Lightroom 5...my photos when importing into lightroom have some that have lines through them and a few that said all data was not retrieved. I thought it was a bad card but I have imported the pictures elsewhere on my computer and they are fine.
Seeing corrupted photos upon import into LR is invariably a sign of hardware problems. It could be the card, the card reader, computer memory, or even (less likely) your disk. Beware that when you view raw files in other applications, they are often showing you the embedded JPEG preview, which is less susceptible to hardware problems.