sd card not recognise after last software update

Until recently my Mac Book Pro doesn't recognise my photo SD card, or any SD card reader I plu via a USB card. My photos are therefore stuck in my camera. I managed to download them via my Ipad then transfer them into Dropbox but then I am losing all my RAW files, and only have the jpeg... Was that an issue due after the latest OS X Yosemite update? Maybe it would be an idea to fix this instead of building gadgets such as the Apple Watch! Very upset and hours of work wasted!