(Close): US shares recovered some of Friday's sharp losses but biotech shares dragged down the Nasdaq's gains.
The Dow Jones closed at 16,510.19, up 0.77%, while the S&P 500 closed up almost 0.5% at 1,967.22.
The Nasdaq closed up 0.04% at 4,828.95, dented by losses in biotech firms.
Biotech shares fell sharply after Democratic presidential candidate Hillary Clinton pledged to take action against firms hiking prices for specialty drugs.
Shares in Immunogen ended the day down 15.9%, while Advaxis ended down 14.86%.
Oil prices were up after data showed a slowdown in drilling in the US.
West Texas Intermediate crude closed up 1.44% after a report showed that US firms have cut the number of oil rigs in operation for the third week in a row.
"The fall in rig counts (is) supporting an otherwise bearish market," said Tamas Varga, an oil analyst at London brokerage PVM Oil Associates.
Shares in GoPro tumbled 8.19% after a gloomy report on the outlook for the video camera maker appeared in the business magazine Barron's on Sunday.
The report said GoPro shares could fall sharply as new products have been underwhelming and competition in its market is growing.
On Friday US shares fell sharply after US Federal Reserve chair Janet Yellen said there were worries about "a risk of a more abrupt slowdown than most analysts expect".
The central bank next meets to decide interest rate policy on 27-28 October, but many economists now think it will delay raising the cost of borrowing until next year.
