How could she do it? How could Linda Bloodworth-Thomason crank out caustic one-liners day after day while her mother was dying?

How could she, in longhand on yellow legal pads, write script after script for the comedic "Designing Women" while holding the hand of her mother, Claudia?People who did not know Bloodworth-Thomason well would comment: "You must not care. You must not be very close to your mother." Nothing, she said, could be further from the truth.

"I was closer to my mother than anyone in the world," she said. "I still cry every day over her. But my parents instilled this thing in me: When you have an opportunity, you have to do your very best."

The year was 1986. Claudia Bloodworth had had open heart surgery in 1983 and contracted AIDS from a blood transfusion. Bloodworth-Thomason, who grew up in Poplar Bluff, Mo., had been working as a free-lance writer in Los Angeles since 1975.

"Designing Women" - which was to premiere that September - was Bloodworth-Thomason's baby. She had conceived the idea, chosen the actresses and sold the series to CBS. Even though her mother died later that year, Bloodworth-Thomason would write 35 consecutive episodes (covering the first season and part of the second) - by herself.

"The writing balanced the tragedy for me," Bloodworth-Thomason, 42, said. "Somehow I was honoring (my mother) by doing that. If I couldn't have worked at home and had her there with me, I couldn't have done it."

Her new television series, "Evening Shade," starring Bert Reynolds and Hal Holbrook, debuted this fall on CBS.

Owned and produced by Linda and husband Harry Thomason's Mozark Productions with MTM Enterprises and CBS Entertainment, the series portrays a family in a small town in Arkansas: a high school football coach, his wife and children.

Evening Shade is, in fact, the name of a small town in northern Arkansas, north of Batesville and near the Strawberry River.

"I had thought of using Poplar Bluff," Bloodworth-Thomason said, "but that's a little hard to say, I think - not quite poetic enough. Hillary Clinton, the first lady of Arkansas, suggested Evening Shade. As soon as she said it, I knew that was it."

Bloodworth-Thomason called the new series a "heart debt" to her parents. Her father, Ralph Bloodworth, a lawyer, died in 1982.

"The essence of their relationship will be the basis for `Evening Shade,' " she said. "It's a high-voltage sexual relationship on a half-hour show. I think there isn't enough good sex on TV. There's plenty of violent sex, rape and infidelity, but I wanted to show a happy, healthy relationship.

"My mother and father were very romantic. He wouldn't hesitate to take her in his arms, bend her over and kiss her in front of us. They fought in front of us, too, and I think that was good. It was very Southern."

Reynold's character in "Evening Shade" also will draw from the experiences of Harry Thomason, 49, who was a high school football coach in Hampton, Ark., before becoming an independent film maker.

The daughter in the series, a Huck Finn-type, is based on a young Bloodworth-Thomason.

"My parents had a cabin on the Current River" near Doniphan, Mo., said Bloodworth-Thomason. "By the time I was 9 I had my own boat, my own canoe with a motor. I did anything I wanted to on that river alone. I knew every slough.

"That, more than anything else, shaped me."

Bloodworth-Thomason was a cheerleader and was voted "most popular" in her senior class of 365 students at Poplar Bluff High. She earned a degree in English at Mizzou and afterward planned to study law.

"I was all set to go" to law school, Bloodworth-Thomason said, "but I had some friends who were moving to L.A. You know how you make those crazy decisions when you're young . . . I really had nothing in mind. I just decided to go."

Her first West Coast job was selling advertising for the Wall Street Journal. Next she became a reporter for a legal newspaper.

Next she took a job as a high school English teacher. She worked at a school surrounded by housing projects in Watts because she "wanted to make a difference."

Like a swift river current, each job carried Bloodworth-Thomason toward her present vocation. A friend she met while teaching, actress Mary Kay Place, who at the time was a secretary, suggested that she and Bloodworth-Thomason team up to write a television script.

The two wrote a "spec" script for Mary Tyler Moore. The script was read by Larry Gelbart, the creator of "M.A.S.H." He asked to see more.

Bloodworth-Thomason's first "M.A.S.H.' episode was nominated for an Emmy. Later, Good Housekeeping magazine named her comedy writer of the year.

With Gelbart as her mentor she continued to write for "M.A.S.H." on a free-lance basis. She and Place were the only women writers for the series.

For the next seven years Bloodworth-Thomason wrote for "M.A.S.H." and "Mary Tyler Moore." She also generated several pilots.

Finally, in 1982, she sold CBS on "Filthy Rich," a prime-time soap opera about people with lots of money and no scruples. It lasted only one season. "It went from No. 1 to No. 78 in two weeks," Bloodworth-Thomason said. "It was a jarring lesson."

That disappointment, however, was eased by her relationship with Harry Thomason, whom she'd met in 1980 at the Columbia studios. She'd noticed his Arkansas accent and introduced herself.

"I know it sounds corny, but we really did fall madly in love," Bloodworth-Thomason said. "I'd had some other long-term relationships, but whenever the subject of marriage came up I'd always say, `Let's wait until next summer.' But with Harry, I would have married him the week after we met."

They were married in July 1983, a year after her father and her sister-in-law both died of cancer.

Bloodworth-Thomason had a commitment to CBS to create a series for a particular actor. Instead she told the network she wanted to take actresses Delta Burke, Dixie Carter, Jean Smart and Annie Potts, all good friends of hers, and "make them talk."

CBS agreed and "Designing Women" was launched. The four outspoken women run an interior design business in Atlanta. They amuse, and sometimes shock, viewers with their sharp-tongued but good-natured conversation, often addressing serious and controversial topics within the comedy frame-work.

"Linda is exactly what is portrayed on that show," said Diane Mitchell, a clinical therapist in Dexter, Mo., who has been best friends with Bloodworth-Thomason since the two met in the fourth grade.

"I can see her in all four characters. She's sassy, but then she's very loving and tender, too."

The show, in essence, is a forum for the opinions of the former Swamp-east Missouri river rat.

"I try to stir things up," Bloodworth-Thomason said. "The show is preachy by design. The women are Southern, and being Southern is being preachy."

Although the critics and a loyal audience loved "Designing Women," the show was canceled in the spring of 1987. Deluged by more than 50,000 letters, the result of a campaign organized by Thomason and the Viewers for Quality Television, CBS reconsidered and the series was saved from the death sentence.

Since then it has climbed in the ratings and become one of CBS' top shows.

Bloodworth-Thomason still is the only "staff writer" for "Designing Women," although she has relinquished some of the script duties to Pam Norris, a free-lance writer from Atlanta who went to Harvard and wrote for "Saturday Night Live."

Bloodworth-Thomason wrote the first "six or seven" scripts for "Evening Shade" by herself.

If and when television burnout comes, Harry and Linda would like to write and produce films and plays. Another goal is to establish a home and studio in Little Rock, Ark., where the couple wants to live for part of each year.

Extraordinarily loyal to the people she loves, Bloodworth-Thomason has not forgotten her hometown or her family.

As a tribute to her mother she has begun the Claudia Company, a foundation that provides college scholarships for rural Ozark women. She has started a reading incentive program at Poplar Bluff High and will sponsor a course in self-defense for girls and women at the school.

Bloodworth-Thomason also is planning a documentary on blood-banking and blood-transferred AIDS. A lawsuit that her family filed against the American Red Cross in the death of her mother was settled this year. Now she wants to assist families of other blood-transferred AIDS patients in their litigation.

"I want to change the way blood-banking is done," Bloodworth-Thomason said. "I want the Red Cross to be held culpable for the thousands of victims and to be responsible in their screening. It's going to be a project in my life for a long time."