Gene Tree Labeling Using Nonnegative Matrix Factorization on Biomedical Literature

Table 2

Sample collection with dictionary terms displayed in bold.

Document	Text
d1	Work-related stress can be considered a factor contributing to anxiety.
d2	Liver cancer is most commonly associated with alcoholism and cirrhosis. It is well-known that alcoholism can cause cirrhosis and increase the risk of kidney failure.
d3	Bone marrow transplants are often needed for patients with leukemia and other types of cancer that damage bone marrow. Exposure to toxic chemicals is a risk factor for leukemia.
d4	Different types of blood cells exist in bone marrow. Bone marrow procedures can detect tuberculosis.
d5	Abnormal stress or pressure can cause an anxiety attack. Continued stress can elevate blood pressure.
d6	Alcoholism can cause high blood pressure (hypertension) and increase the risk of birth defects and kidney failure.
d7	The presence of speech defects in children is a sign of autism. As of yet, there is no consensus on what causes autism.
d8	Alcoholism, often triggered at an early age by factors such as environment and genetic predisposition, can lead to cirrhosis. Cirrhosis is the scarring of the liver.
d9	Autism affects approximately 0.5% of children in the US. The link between alcoholism and birth defects is well-known; researchers are currently studying the link between alcoholism and autism.