American Management Systems Inc., an Arlington computer services and management consulting firm, yesterday reported that first-quarter profits rose to $536,000 36 cents a share) from $378,000 (30 cents) in the same period last year.

Per-share earnings were up 20 percent, compared with the 42 percent increase in overall net income, reflecting additional shares issued in the company's initial public stock offering last April. Revenues were up 34 percent to $14 million, AMS said.

Cheapeake Corp. of Virginia, a forest products company, reported first-quarter profits of $5.8 million (94 cents a share) compared with $3.8 million (63 cents). Sales rose to $58 million from $48 million. President Larence Camp said there has been a "softening of demand" for its paper products.

CACI Iinc., an Arlington professional research and analysis company, reported earnings in the nine months ended March 31 of $1.3 million ($1.28 a share) compared with $841,000 (82 cents) a year earlier. Revenues increased 78 percent to $24 million.

Alcolac Inc., A Baltimore manufacturer of specialty chemicals, said earnings for the nine months ended March 31 rose to $1.18 million (85 cents a share) from $995,000 (71 cents) as sales rose to $28 million from $24.5 million.

Noxell Corp., a Baltimore cosmetics firm, said earnings rose 8 percent in the first quarter to $5.3 million ($1.08 a share) from $4.9 million (97 cents) as sales increased 10.6 percent to $58 million.