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Polycythemia vera (pol-e-sigh-THEE-me-uh VEER-uh) is a slow-growing type of blood cancer in which your bone marrow makes too many red blood cells. Polycythemia vera may also result in production of too many of the other types of blood cells — white blood cells and platelets. These excess cells thicken your blood and cause complications, such as such as a risk of blood clots or bleeding. Polycythemia vera isn't common. It usually develops slowly, and you may have it for years without noticing signs or symptoms. Often, polycythemia vera is found during a blood test done for some other reason. Without treatment, polycythemia vera can be life-threatening. However, with proper medical care, many people experience few problems related to this disease. Over time, there's a risk of progressing to more-serious blood cancers, such as myelofibrosis or acute leukemia.
Ankylosing spondylitis is an inflammatory disease that, over time, can cause some of the vertebrae in your spine to fuse. This fusing makes the spine less flexible and can result in a hunched-forward posture. If ribs are affected, it can be difficult to breathe deeply. Ankylosing spondylitis affects men more often than women. Signs and symptoms typically begin in early adulthood. Inflammation also can occur in other parts of your body — most commonly, your eyes. There is no cure for ankylosing spondylitis, but treatments can lessen your symptoms and possibly slow progression of the disease.
This video: Polycystic ovary syndrome (PCOS) is a common endocrine system disorder among women of reproductive age. Women with PCOS may have enlarged ovaries that contain small collections of fluid — called follicles — located in each ovary as seen during an ultrasound exam. Infrequent or prolonged menstrual periods, excess hair growth, acne, and obesity can all occur in women with polycystic ovary syndrome. In adolescents, infrequent or absent menstruation may raise suspicion for the condition. The exact cause of polycystic ovary syndrome is unknown. Early diagnosis and treatment along with weight loss may reduce the risk of long-term complications, such as type 2 diabetes and heart disease.
During normal sleep, you cycle through REM and four stages of non-REM (NREM) sleep numerous times a night. Stage 1 of NREM sleep is the lightest, while stage 4 is the deepest. When you're repeatedly interrupted and can't cycle normally through these types and stages of sleep, you may feel tired, fatigued, and have trouble concentrating and paying attention while you're awake. Sleepiness puts you at greater risk for car wrecks and other accidents.
Asthma was originally described as an inflammatory disease that predominantly involves the central airways. Pathological and physiological evidence reported during the past few years suggests that the inflammatory process extends beyond the central airways to the peripheral airways and the lung parenchyma. The small airways are capable of producing T-helper-2 cytokines, as well as chemokines, and they have recently been recognized as a predominant site of airflow obstruction in asthmatic persons. The inflammation at this distal site has been described as more severe than large airway inflammation. These findings are of great clinical significance, and highlight the need to consider the peripheral airways as a target in any therapeutic strategy for treatment of asthma.