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Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Intradermal injections are somewhat difficult to correctly administer because the skin layers are so thin that it is easy to accidentally punch through to the deeper subcutaneous layer.
Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.
According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.
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