Digene shares were among the best performing local stocks last week after the Food and Drug Administration approved the company's test for cervical cancer as a primary screening tool.

Digene's test had previously been used only as a follow-up examination. Shares in the Gaithersburg biotechnology company closed Friday at $20 a share, up $4.48, or 29 percent.

The Washington Post-Bloomberg regional stock index closed Friday at 163.27, up 3.16 points for the week. The NVTC Potomac Tech 60, which tracks the shares of 60 local technology firms, closed at 529.56, down less than a point from the previous week.

Among falling stocks, three software companies led the way after each one said its sales during the first three months of the year were hurt by economic uncertainty, especially as it related to war in Iraq. Visual Networks of Rockville and Maximus of Reston lowered forecasts for sales and earnings for the first three months of the year. WebMethods of Fairfax said slower sales would effect its quarterly revenue, but not net earnings.

Shares in Visual Networks closed the week at $1.26, down 24 cents, or 16 percent. Maximus shares closed Friday at $18.25, down 14 percent, or $3.01. WebMethods ended the week at $8.81, down 34 cents, or 4 percent.

Shares in Nextel Communications , a Reston wireless telecommunications company, also were lower last week. On Monday the company filed with the Securities and Exchange Commission to sell as much as $5 billion in securities in the form of debt, preferred stocks, common shares or other financial instruments. The stock closed on Friday at $12.29, down $1.31 or 10 percent.

AES , a global energy company, closed the week up 30 percent. The Arlington company's stock rose sharply Friday after AES announced plans to borrow up to $1 billion to pay back other debt. The debt buyback would remove some uncertainty about the company's future cash position, analysts said. Shares in AES rose 30 percent for the week, closing Friday at $4.70, up $1.08

GTSI of Chantilly, a government contractor, announced a new information technology services contract worth up to $100 million and a $5 million repurchase of the company's shares. The stock closed Friday up 25 percent or $1.66, to $8.39.