U.S. researchers looking at how stress affects the gut stumbled upon a potent chemical that caused mice to regrow hair by blocking a stress-related hormone, said a study on Wednesday.

While the process has not yet been tested in humans, it grew more hair in mice than minoxidil, the ingredient in Rogaine, a popular treatment for baldness, said the study in the online journal PLoS One.

Almost 10,000 infants and toddlers are hurt in crib and playpen accidents each year, according to the first nationwide analysis of emergency room treatment for these injuries.

Most injuries were from falls in toddlers between ages 1 and 2 — generally old enough to attempt climbing out of a crib or playpen.

Up to 10 percent of rice grown in China is contaminated with harmful heavy metals stemming from pollution linked to the nation's rapid industrialization, a report said.

This week's edition of the New Century magazine cited studies showing that large amounts of Chinese rice have been tainted with heavy metals like cadmium for years but that little has been done to highlight the dangers.

Eat more fiber and you just may live longer.

That's the message from the largest study of its kind to find a link between high-fiber diets and lower risks of death not only from heart disease, but from infectious and respiratory illnesses as well.

Labor pain is nothing to laugh at. Yet.

The use of nitrous oxide, or laughing gas, during childbirth fell out of favor in the United States decades ago, and just two hospitals — one in San Francisco and one in Seattle — still offer it. But interest in returning the dentist office staple to the delivery room is growing: respected hospitals including Dartmouth-Hitchcock Medical Center plan to start offering it, the federal government is reviewing it, and after a long hiatus, the equipment needed to administer it is expected to hit the market soon.

At least 20 people have died of swine flu in China this year, the health ministry said Friday, but officials said there was no reason to panic even as the flu season reaches its peak.

The fatalities from A(H1N1) influenza have been recorded in at least nine locations since mid-January, the ministry said.

Studies on animals suggest that a new hybrid drug, made in part from the chemical in the yellow spice turmeric, could help regenerate brain cells after a stroke, US researchers said Wednesday.

The molecular compound is made with curcumin, a natural yellow pigment that originates from a perennial herb called Curcuma longa and is popular in South Asian and Middle Eastern foods, particularly curries.

Babies lucky enough not to get HIV from their infected mothers still face up to a four times greater risk of dying in the first year because of a greater susceptibility to infectious disease, said a study Tuesday.

Researchers examined around 100 mothers and their babies in South Africa, and compared antibody levels among children who were born infected with HIV to children who escaped HIV, a group described as HIV-exposed infants.

For the first time in the history of heart disease research, a certain type of treatment has proven more effective in women than in men, according to a U.S. study published Monday.

The research found that women saw a 70 percent reduction in heart failure compared to men who saw a 35 percent drop when using cardiac resynchronization therapy with defibrillator (CRT-D), indicating it works twice as well in women.

Scientists in Britain have successfully tested a vaccine which could work against all known flu strains, the Guardian newspaper reported Monday.

The new vaccine, developed by scientists at Oxford University, differs from traditional treatments by targeting proteins inside the flu virus rather than proteins on the flu's external coat.