THURSDAY, Sept. 9 (HealthDay News) -- Most teenagers think they're invincible, and that goes double for talented teenage athletes. They're young, immortal, at the top of their game, the envy of their friends.

FRIDAY, Sept. 10 (HealthDay News) -- They're the ultimate creepy crawler. Creatures that truly give people the willies. And they're apt to make you feel unclean, or maybe even a bad parent (neither of which, experts say, is valid).

FRIDAY. Sept. 10 (HealthDay News) -- For Lisa Byrns, a school nurse, dealing with head lice brings out the investigator in her.

(HealthDay News) -- Pancreatitis occurs when the pancreas, a gland near the stomach that helps you digest food, becomes inflamed.

(HealthDay News) -- If you have high blood pressure, it's important to get it under control before you become pregnant. High blood pressure during pregnancy can be dangerous for both mom and baby.

FRIDAY, Sept. 10 (HealthDay News) -- Reducing the unnecessary transfer of patients between hospitals (secondary over-triage) may be a way to decrease U.S. health-care system costs, a new study suggests.

FRIDAY, Sept. 10 (HealthDay News) -- Significant distrust of the health-care system is a major reason why black Americans donate blood at lower rates than whites, says a new study.

FRIDAY, Sept. 10 (HealthDay News) -- Taking multivitamins does not reduce colorectal cancer patients' risk of dying or, among survivors, the likelihood that the cancer will return, a new study shows.

FRIDAY, Sept. 10 (HealthDay News) -- Young women are more likely to use birth control if their partners are in favor of it, new study findings suggest.

FRIDAY, Sept. 10 (HealthDay News) --Some dieters may be more likely than others to regain any excess pounds they've lost, depending on their particular hormonal makeup, new Spanish research cautions.

FRIDAY, Sept. 10 (HealthDay News) -- Testing simple physical abilities may help predict a person's risk of death, suggests a new study.

FRIDAY, Sept. 10 (HealthDay News) -- Patients who experience sudden cardiac arrest outside of a hospital setting fare just as well when treated with chest compressions before being treated with an electrical defibrillator as they do when getting immediate defibrillation, new research indicates.

FRIDAY, Sept. 10 (HealthDay News) -- Many young people consider getting drunk an important part of being accepted as part of a social group, a factor that needs to be considered when creating anti-drinking campaigns, a British researcher says.

FRIDAY, Sept. 10 (HealthDay News) -- The U.S. Food and Drug Administration may soon approve genetically modified salmon for humans to eat, a prospect that is raising concern among some consumer advocates who consider the fish a threat to both health and the environment.

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:

FRIDAY, Sept. 10 (HealthDay News) -- For patients aged 70 and older who have a blocked neck artery, inserting a stent to reopen the artery is riskier than surgically widening the artery, a new study finds.

FRIDAY, Sept. 10 (HealthDay News) -- A treatment for poisoning from pesticides and similar chemicals has been approved by the U.S. Food and Drug Administration for use in children, nearly 50 years after it was first approved for adults.