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A hormone is a chemical messenger that enables communication between cells. Hormones are secreted by the glands of the endocrine system and they serve to maintain homeostasis and to regulate numerous other systems and processes, including reproduction and development.
It then spreads down the bundle of his and then purkinje fibres to cause ventricular contraction. So when viewing the heart from the front, the direction of depolarisation is 11 o'clock to 5 o'clock. The general direction of depolarisation is known as the cardiac axis.
You get motion sickness when one part of your balance-sensing system (your inner ear , eyes, and sensory nerves) senses that your body is moving, but the other parts don't. For example, if you are in the cabin of a moving ship, your inner ear may sense the motion of waves, but your eyes don't see any movement.
Results Sinusitis was characterized as acute in 26 patients, subacute in 5 (including 1 pyocele), and chronic in 8 (including 2 fungal infections). No tumors were found. Isolated sinus cysts were excluded from the study. Headache, the main symptom in 32 patients (82%), was localized most commonly on the vertex. Other common complaints were rhinitis, dizziness, eye symptoms, and fever. In 2 patients, the finding was occult. Eight patients (21%) presented with cranial nerve deficits, and 1 patient had an intracranial complication. Sinus irrigation was performed in 16 patients (41%) and sphenoidotomy was performed in 10 (26%). Fifteen patients (38%) were treated with antibiotic drugs alone. Within 3 months, 31 (84%) of 37 patients had recovered from the illness; 5 still experienced headaches despite having normalized radiographic findings; and 1 had permanent unilateral visual loss. Two patients were lost to follow-up.
Trisomy 18, also called Edwards syndrome, is a chromosomal condition associated with abnormalities in many parts of the body. Individuals with trisomy 18 often have slow growth before birth (intrauterine growth retardation) and a low birth weight. Affected individuals may have heart defects and abnormalities of other organs that develop before birth. Other features of trisomy 18 include a small, abnormally shaped head; a small jaw and mouth; and clenched fists with overlapping fingers. Due to the presence of several life-threatening medical problems, many individuals with trisomy 18 die before birth or within their first month. Five to 10 percent of children with this condition live past their first year, and these children often have severe intellectual disability.
Endometriosis (en-doe-me-tree-O-sis) is an often painful disorder in which tissue that normally lines the inside of your uterus — the endometrium — grows outside your uterus. Endometriosis most commonly involves your ovaries, fallopian tubes and the tissue lining your pelvis. Rarely, endometrial tissue may spread beyond pelvic organs.
Diabetes insipidus (die-uh-BEE-teze in-SIP-uh-dus) is an uncommon disorder that causes an imbalance of water in the body. This imbalance leads to intense thirst even after drinking fluids (polydipsia), and excretion of large amounts of urine (polyuria). While the names diabetes insipidus and diabetes mellitus sound similar, they're not related. Diabetes mellitus — which can occur as type 1 or type 2 — is the more common form of diabetes. There's no cure for diabetes insipidus, but treatments are available to relieve your thirst and normalize your urine output.
A hemolytic transfusion reaction is a serious complication that can occur after a transfusion of blood. The red blood cells that were given in the transfusion are destroyed by the patient's immune system. There are other types of allergic transfusion reactions that do not cause hemolysis.
The superior sagittal sinus (also known as the superior longitudinal sinus), within the human head, is an unpaired area along the attached margin of falx cerebri. It allows blood to drain from the lateral aspects of anterior cerebral hemispheres to the confluence of sinuses.
Cerebral palsy refers to brain damage that occurs before a child is five years old. Therefore, adults cannot develop cerebral palsy. However, cerebral palsy does not get better or worse with age, so when a child has the condition, he or she will continue to have the condition into adulthood.
Chorionic villus sampling, often referred to as CVS, is a diagnostic test for identifying chromosome abnormalities and other inherited disorders. This test may be recommended by your health care provider, if you or your partner has family medical histories that reveal potential risks.
The cause of HELLP syndrome is unknown, but there are certain factors that may increase your risk of developing it. Preeclampsia is the greatest risk factor. This condition is marked by high blood pressure and swelling, and it typically occurs during the last trimester of pregnancy.
A patient who has a problem with proprioception can still maintain balance by using vestibular function and vision. In the Romberg test, the standing patient is asked to close his or her eyes. A loss of balance is interpreted as a positive Romberg's test.
Progeria (pro-JEER-e-uh), also known as Hutchinson-Gilford syndrome, is an extremely rare, progressive genetic disorder that causes children to age rapidly, beginning in their first two years of life. Children with progeria generally appear normal at birth. During the first year, signs and symptoms, such as slow growth and hair loss, begin to appear. Heart problems or strokes are the eventual cause of death in most children with progeria. The average life expectancy for a child with progeria is about 13 years, but some with the disease die younger and some live 20 years or longer. There's no cure for progeria, but ongoing research shows some promise for treatment.
Antiarrhythmics are drugs that are used to treat abnormal heart rhythms resulting from irregular electrical activity of the heart. There are many different types of antiarrhythmic drugs. Examples include: Amiodarone (Cordarone) Flecainide (Tambocor) Procainamide (Procanbid) Sotalol (Betapace) In addition, there are other types of heart drugs that can be used to treat arrhythmias, including: Beta-blockers such as metoprolol or Toprol XL, which reduce the heart's workload and heart rate. Calcium channel blockers such as verapamil or Calan, which also reduces the heart rate.