(HealthDay News) -- Hemophilia is a disorder in which the blood doesn't properly clot, so stopping bleeding becomes more difficult.

(HealthDay News) -- Bipolar disorder causes major mood swings, ranging from depression to manic (elevated) mood.

THURSDAY, Jan. 27 (HealthDay News) -- Celiac disease and Crohn's disease share several genetic risk factors, a new study finds.

THURSDAY, Jan. 27 (HealthDay News) -- Modern humans first left Africa much earlier than previously believed, new research suggests.

THURSDAY, Jan. 27 (HealthDay News) -- Work-related hearing loss can lead to sleep problems, a new study has found.

THURSDAY, Jan. 27 (HealthDay News) -- Most preschool children develop a taste for salt, sugar and fat at home, and quickly learn which types of brand-name fast foods and sodas meet these preferences, U.S. researchers say.

THURSDAY, Jan. 27 (HealthDay News) -- Only 42 percent of Americans say they sleep well almost every night and can therefore be categorized as "great sleepers," according to a new National Sleep Foundation survey.

THURSDAY, Jan. 27 (HealthDay News) -- Here's some good news for women ever bothered by hot flashes and other menopausal symptoms: Your risk for breast cancer may be reduced as much as 50 percent, researchers from the Fred Hutchinson Cancer Research Center in Seattle report.

THURSDAY, Jan. 27 (HealthDay News) -- Electroshock devices, currently classified by the U.S. Food and Drug Administration as high risk for the treatment of severe depression, could be downgraded to medium risk this year.

THURSDAY, Jan. 27 (HealthDay News) -- David Burley was excited about a new restaurant opening in his small Louisiana town, where vacant storefronts have become the norm as the recession lingers.

THURSDAY, Jan. 27 (HealthDay News) -- Researchers have found that brain cancer cells can turn themselves into blood vessel cells to counter drugs designed to cut off a tumor's blood supply and deprive it of oxygen and nutrients.

THURSDAY, Jan. 27 (HealthDay News) -- About one-fourth of all black men and women carry a genetic mutation that dramatically reduces their risk for coronary artery disease, new research reveals.

Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

(HealthDay News) -- Here are the latest clinical trials, courtesy of ClinicalConnection.com:

THURSDAY, Jan. 27 (HealthDay News) -- Arizona Congresswoman Gabrielle Giffords began intensive rehabilitation therapy in Houston Thursday, another stunning step forward for the lawmaker who was shot in the brain earlier this month.

THURSDAY, Jan. 27 (HealthDay News) -- U.S. health authorities on Thursday issued an "interim guidance" to help doctors and patients using Truvada, the once-a-day combination pill that was shown in November to help prevent the spread of HIV in high-risk individuals.

THURSDAY, Jan. 27 (HealthDay News) -- Even babies seem to know that might makes right, according to new research that suggests infants use size as a measure to predict who will prevail when two individuals have a conflict.