Richard Knox

Federal officials say a large study of premature infants was ethically flawed because doctors didn't inform the babies' parents about increased risks of blindness, brain damage and death.

The study involved more than 1,300 severely premature infants at nearly two dozen medical institutions between 2004 and 2009. The infants were randomly assigned to receive two different levels of oxygen to see which was better at preventing blindness without increasing the risk of neurologic damage or death.

Sixteen cases of a new flu around Shanghai have touched off a major effort to determine what kind of threat this new bug might be.

The victims range in age from 4 to 87 years old. Six have died. It is a tragedy for them and their families, but is it a global crisis?

To understand why so few cases are generating so much concern, the first thing to know is that no flu virus like this one — called H7N9 — has ever been known to infect humans before.

Most people (including a lot of doctors) think of a stroke as something that happens to old people. But the rate is increasing among those in their 50s, 40s and even younger.

In one recent 10-year period, the rate of strokes in Americans younger than 55 went up 84 percent among whites and 54 percent among blacks. One in 5 strokes now occurs in adults 20 to 55 years old — up from 1 in 8 in the mid-1990s.

The largest gene-probing study ever done has fished out dozens of new genetic markers that flag a person's susceptibility to breast, ovarian and prostate cancer.

The 74 newly discovered genetic variants double the previously known number for these malignancies, all of which are driven by sex hormones.

Underscoring the sheer magnitude of the findings, they're contained in 15 scientific papers published simultaneously by five different journals. The Nature group of journals has collected them all here.

Mammography outcomes from nearly a million U.S. women suggest which ones under 50 would stand the greatest chance of benefiting from regular screening: those with very dense breasts.

That's been a bone of contention ever since a federal task force declared nearly four years ago that women younger than 50 shouldn't routinely get the test.

Nothing sends more kids to the hospital than asthma.

So when doctors at Children's Hospital in Boston noticed they kept seeing an unusually high number of asthmatic kids from certain low-income neighborhoods, they wondered if they could do something about the environment these kids were living in.

Just last week AIDS researchers were excited about a Mississippi toddler whose blood has remained free of HIV many months after she stopped getting antiviral drugs – what doctors call a "functional cure."

Every day something like 550 hospitalized Americans suffer cardiac arrest. That's bad news. Only about one in five will live to leave the hospital.

But for the lucky 44,000 a year who are resuscitated and survive, the outlook is much better than expected, authors of a new study say.

Picture this: Your spouse or child has collapsed and isn't breathing. You call 911, and the paramedics rush in and take charge. But you are banished to another room while the medical people try to bring your loved one back to life.

It's about the most stressful scene imaginable. And it's what usually happens.

It's not the first study that finds the lowly aspirin may protect against the deadliest kind of skin cancer, but it is one of the largest.

And it adds to a mounting pile of studies suggesting that cheap, common aspirin lowers the risk of many cancers — of the colon, breast, esophagus, stomach, prostate, bladder and ovary.