SEVERE tracheal stenosis can not only cause criti-cal medical problems such as severe shortness of breath,hypoxia,and even orthopnea,but also impose overwhelmin
APLASTIC anemia (AA) is a bone marrow failure disease caused by abnormal activation of T lymphocytes,resulting in the apoptosis of he-matopoietic cells and bone
ORAL contraceptives are widely used to prevent pregnancy.A number of studies have dem-onstrated the increased risk of venous throm-boembolism in women taking or