TUESDAY, Jan. 19 (HealthDay News) -- Birds don't become sick when exposed to the H1N1 influenza strains that caused the 1918 and 2009 global flu pandemics, a finding that suggests birds played no role in the spread of the pandemic-causing viruses, according to a new study.

TUESDAY, Jan. 19 (HealthDay News) -- Transplanted neurons grown from embryonic stem cells were able to form proper brain connections in newborn mice, U.S. scientists report.

TUESDAY, Jan. 19 (HealthDay News) -- New research offers insight into how a carcinogen in tobacco known as NNK contributes to the formation of lung cancer tumors.

TUESDAY, Jan. 19 (HealthDay News) -- The cholesterol drugs known as statins hold promise as a treatment for sickle cell disease, a common genetic disorder, new research has found.

TUESDAY, Jan. 19 (HealthDay News) -- Many health risks of excess weight are well-known, such as heart disease, high blood pressure and diabetes, to name a few. But an obese patient is also a challenge for an anesthesiologist to care for during surgery.

TUESDAY, Jan. 19 (HealthDay News) -- Scientists think they have uncovered at least one of the reasons why omega-3 fatty acids are good for your heart.

TUESDAY, Jan. 19 (HealthDay News) -- The majority of European males are descended from farmers who migrated from the Near East 10,000 years ago, say English researchers who examined the diversity of the Y chromosome, which is passed from father to son.

TUESDAY, Jan. 19 (HealthDay News) -- A mutation in a gene called ZFP191 causes central nervous system myelination problems in mice that are similar to what occurs in humans with multiple sclerosis, new research has found.

TUESDAY, Jan. 19 (HealthDay News) -- Researchers report that they've developed a new way to find compounds that could become treatments for degenerative nerve disorders such as Alzheimer's, Huntington's and Parkinson's diseases.

TUESDAY, Jan. 19 (HealthDay News) -- Monkey see, monkey do simple math?

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:

TUESDAY, Jan. 19 (HealthDay News) -- DNA testing for the human papillomavirus should replace the Pap smear as the main way to screen women for cervical cancer, according to Italian researchers.

TUESDAY, Jan. 19 (HealthDay News) -- Not only does cigarette smoke cause lung cancer, it worsens the disease by increasing lung inflammation, U.S. researchers have found.

TUESDAY, Jan. 19 (HealthDay News) -- The more complex a person's diet plan, the sooner the person will abandon it, a new study finds.

TUESDAY, Jan. 19 (HealthDay News) -- Adding fish oil to intravenous solutions proved beneficial for intensive care patients with the potentially lethal blood infection known as sepsis, a new study finds.

TUESDAY, Jan. 19 (HealthDay News) -- A study of obsessive-compulsive Dobermans might someday help explain similar repetitive behaviors in humans.

TUESDAY, Jan. 19 (HealthDay News) -- Overdoses from prescription painkillers are increasing in the United States, a new study shows.

(HealthDay News) -- Mononucleosis, often dubbed "mono," is a viral infection that can cause fatigue, weakness, sore throat and fever.

(HealthDay News) -- A stress fracture occurs from overuse, when muscles become too weak to absorb the continued stress of physical activity, causing a small crack in a bone.