Scientists had long tried to duplicate the procedure that led to the first long-term remission 12 years ago, and their surprise success seems to confirm that a cure for H.I.V. infection is possible, if difficult, researchers said. Their findings are set to be published today.

The details: Both remissions came after bone-marrow transplants, which are risky and have harsh side effects that can last for years. But rearming the body with immune cells modified to resist H.I.V. might succeed as a practical treatment, experts said.

New mood of resistance in Congress

Senator Mitch McConnell, the majority leader, acknowledged on Monday that he could not prevent the passage of a resolution overturning President Trump’s national emergency declaration, setting up what would be the first veto of this administration.

With the support of at least four Republican senators, Democrats now have the 51 votes they need to pass the measure. It would apparently be the first time since passage of the National Emergencies Act of 1976 that Congress has voted to overturn an emergency declaration.