The networks are still several weeks away...

The networks are still several weeks away from announcing their prime-time program lineups for fall, but NBC has already given pickups to seven of its series: “The Cosby Show,” “Family Ties,” “Cheers,” “Night Court,” “Highway to Heaven,” “St. Elsewhere” and “The Golden Girls.” The early renewal allows producers to get that much ahead in developing stories and scripts for next season.

Kate Mulgrew, who made the jump from daytime’s “Ryan’s Hope” to such prime-time dramas as “Manions of America” and “A Time for Miracles,” will be seen on the ABC soap opera again this week. She originally played the character Mary Ryan back in the mid-1970s, but in her guest appearance this week she’ll portray Maura, who helps Mary’s daughter.

CBS will devote two hours April 20 to coverage of a performance by pianist Vladimir Horowitz in his native Russia, which he has not seen since leaving in 1925. The concert at the Bolshoi Zaal in the Moscow Conservatory will be seen on a tape-delayed basis on the “Sunday Morning” news program, with anchor Charles Kuralt in Moscow.

You may not have known it, but this is Teri Garr Week. Who says so? NBC’s “Late Night With David Letterman,” that’s who. This week, the comedy show will feature reruns of four shows on which she’s appeared. The actress, who has starred in such films as “Tootsie,” “Young Frankenstein,” “Mr. Mom” and “The Black Stallion,” has been on the late-night program 12 times.

Timothy Bottoms, David Ogden Stiers, Arthur Hill, Barbara Parkins, Tom Bosley and Jon Cypher will appear in the next “Perry Mason” movie, called “The Case of the Notorious Nun.” Due to be telecast this spring, the NBC program will star Raymond Burr, Barbara Hale and William Katt.

Nicolas Surovy is reprising his role as police detective Evan Stark, whom he first played in a TV movie called “Stark,” in a new film for CBS, “Mirrored Image.” Also in the cast are Kirstie Alley, Michelle Phillips, Ben Murphy, Pat Corley, David Ackroyd and Belinda Montgomery.

Garrison Keillor and his acclaimed public radio program, “A Prairie Home Companion,” are coming to the Disney Channel. The pay service says it is preparing a 90-minute special for the Fourth of July weekend called “Lake Wobegon Comes to the Disney Channel.” It will be taped before a live audience at the World Theater in St. Paul, Minn., where Keillor does his radio broadcasts.