It could have been Gen. George C. Patton addressing the Allied troops after their first big victory in North Africa.

At the lectern yesterday in the Parklawn Building in Rockville stood the general -- U.S. Surgeon General C. Everett Koop -- resplendent in black uniform with gold buttons and bars, exhorting the corps to fight the good fight against the enemies of disease and illness.

Koop takes seriously his role as commander of the 5,388-member Commissioned Corps of uniformed health professionals -- whether pinning a medal on a commissioned officer for helping to set up a brown-bag luncheon series, calling for volunteers to serve in drought-stricken Chad, or aiming his guns at one of his favorite targets: cigarette smokers.

"He's done a tremendous job in increasing the espirit de corps," said Susan Lockhart, one of its officers. "There's been a lot more interest in the last few years in wearing the uniform. Most of that comes directly from the surgeon general, who wears his uniform almost all the time."

But after Koop's 45-minute address, some members of his audience -- both in and out of uniform -- said it sounded more like Gen. George Custer giving a pep talk to his men at Little Bighorn.

The corps' ranks have been depleted through budget cuts and layoffs. The Office of Management and Budget would like to contract out to private health groups for some of the services the corps now provides. And the last eight Public Health Service hospitals were closed by the Reagan administration three years ago, according to spokesman Shirley Barth.

"It's like being all dressed up with no place to go," said one officer who heard Koop's speech and who asked not to be quoted by name.

Still, it's a far cry from the Commissioned Corps' early days, when it was founded in 1798 as a marine hospital service for sick seamen.

In the days when the pioneers were pushing westward, what was then the marine service went with them, fighting yellow fever, cholera and smallpox. During the Civil War, the corps tended to wounded soldiers on both sides of the Mason-Dixon Line.

In 1878, the corps got its own uniform; 11 years later Congress organized the corps along military lines, requiring entrance exams and providing for promotion up the ranks. When World War I broke out, President Woodrow Wilson set the precedent for merging the Commissioned Corps with the military in time of emergency.

Since then, the corps has fallen on harder times. It experienced something of a comeback in the 1960s and early 1970s, however, when idealistic college graduates flocked to its ranks. It became, in a sense, a Peace Corps for health care workers.

"We came in in the '60s when we thought it was just a big public service agency," said Officer Carol Rest-Mincberg. "You could make decent money and still feel you were doing something valuable."

Now Commissioned Corps members are assigned primarily to the Indian Health Service for work on reservations, to quarantine centers, to the Centers for Disease Control in Atlanta, and to emergency relief duty here and overseas.

The uniforms have grown a bit musty from disuse, and some corps members grumble about not receiving the same benefits that their health service counterparts in the civil service receive.

Corps members can qualify for pensions similar to those the military receive, but that assumes that they are not laid off before they accrue the minimum 20 years. (Civil servants can qualify for retirement benefits after five years' service.) Corps officers can be assigned and transferred on a moment's notice.

In the best of times, those differences were considered part of the price of belonging to an elite group. Now many officers facing layoffs or transfers say they wish they had the civil service protections.

Koop yesterday made only one mention of budget cuts and layoffs in his address, which was sort of a "State of the Corps" tour through its programs and initiatives of the past few years. Koop said he had fought hard against the OMB's proposal to contract out the health services that the corps now provides to inmates in federal prisons. "We make important contributions that you can't go out and buy on contracts," he said.

Koop used the forum to repeat his pledge to make America "a smoke-free society by the year 2000." He took credit for creating a new antismoking climate in which nonsmokers are becoming increasingly assertive about their rights in public places. He warned of a new danger, however, citing figures showing that 4 percent of U.S. high school students use smokeless tobacco.

But when asked about the potential dangers of cholesterol, Koop drew a round of laughter. "I eat a very high-cholesterol diet," he said, "and enjoy it thoroughly."