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An atrioventricular septal defect (AVSD) is a heart defect in which there are holes between the chambers of the right and left sides of the heart, and the valves that control the flow of blood between these chambers may not be formed correctly
The arm and leg muscles are affected later. Myasthenia gravis (MG) is an autoimmune disease — a disease that occurs when the immune system attacks the body's own tissues. In MG, that attack interrupts the connection between nerve and muscle — the neuromuscular junction.
Natural painkiller found in human spit. Compound in saliva could be more powerful than morphine. A new painkilling substance has been discovered that is up to six times more potent than morphine when tested in rats — and it's produced naturally by the human body.
Dacryocystorhinostomy (DCR) is a procedure performed for the treatment of tearing (epiphora) due to blockage of the nasolacrimal duct. Tears originate in the lacrimal gland, located at the upper outer margin of the eye. As tears cross the eye with each blink, they are directed into small openings in the eyelids called puncta. From this point, tears travel through a pathway known as the canalicular system into the lacrimal sac. The lacrimal sac is located between the eye and the nose, and funnels tears into the nasal cavity through the nasolacrimal duct (Figure 1). As this is quite a long path for tears to travel, there can be many causes of excessive tearing. Blockage of the nasolacrimal duct is one common cause, and can be treated by creating a direct opening from the lacrimal sac into the nasal cavity in a procedure known as DCR. The evaluation and management of tearing may involve both an ophthalmologist and an otolaryngologist.
The pituitary gland is often portrayed as the "master gland" of the body. Such praise is justified in the sense that the anterior and posterior pituitary secrete a battery of hormones that collectively influence all cells and affect virtually all physiologic processes. The pituitary gland may be king, but the power behind the throne is clearly the hypothalamus. As alluded to in the last section, some of the neurons within the hypothalamus - neurosecretory neurons - secrete hormones that strictly control secretion of hormones from the anterior pituitary. The hypothalamic hormones are referred to as releasing hormones and inhibiting hormones, reflecting their influence on anterior pituitary hormones.
Adrenoleukodystrophy, or ALD, is a deadly genetic disease that affects 1 in 18 000 people. It most severely affects boys and men. This brain disorder destroys myelin, the protective sheath that surrounds the brain's neurons -- the nerve cells that allow us to think and to control our muscles.
Diabetic retinopathy involves changes to retinal blood vessels that can cause them to bleed or leak fluid, distorting vision. Diabetic retinopathy is the most common cause of vision loss among people with diabetes and a leading cause of blindness among working-age adults.
Narcolepsy is a chronic sleep disorder characterized by overwhelming daytime drowsiness and sudden attacks of sleep. People with narcolepsy often find it difficult to stay awake for long periods of time, regardless of the circumstances. Narcolepsy can cause serious disruptions in your daily routine. Sometimes, narcolepsy can be accompanied by a sudden loss of muscle tone (cataplexy) that leads to weakness and loss of muscle control. Cataplexy is often triggered by a strong emotion, most commonly laughter. Narcolepsy is a chronic condition for which there's no cure. However, medications and lifestyle changes can help you manage the symptoms. Support from others — family, friends, employer, teachers — can help you cope with narcolepsy.
Red blood cells, most white blood cells, and platelets are produced in the bone marrow, the soft fatty tissue inside bone cavities. Two types of white blood cells, T and B cells (lymphocytes), are also produced in the lymph nodes and spleen, and T cells are produced and mature in the thymus gland.
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column. The brain and spinal cord together make up the central nervous system (CNS).
Trichinosis (trik-ih-NO-sis), sometimes called trichinellosis (trik-ih-nuh-LOW-sis), is a type of roundworm infection. Roundworm parasites use a host body to live and reproduce. Occurring primarily among meat-eating animals (carnivores) — especially bears, foxes and walruses — the infection is acquired by eating roundworm larvae in raw or undercooked meat. When humans eat undercooked meat containing trichinella larvae, the larvae mature into adult worms in the intestine over several weeks. The adult worms then produce larvae that travel through various tissues, including muscle. Trichinosis is most widespread in rural areas throughout the world. Trichinosis can be treated with medication, though it's not always necessary. It's also easy to prevent.