On the site given by Nikita, click on "
"Расширенный поиск" " to access the full-text search mode. There you can type an unit name (in Russian), and eventually a date ,and you will access the list of members of this unit killed.
Another possibility is to use the site
http://allaces.ru/cgi-bin/s2.cgi/sssr/struct/main.dat and to search the unit you're interested in. Most of the referenced units will have a list a unit members attached, and their fate. For most units all crew killed in 1942 will be listed, for some, this covers the whole war.