Posts

Showing posts from August, 2008

Biofeedback

Biofeedback, a technique by which patients monitor their own bodily functions in an attempt to alter those functions. Primarily used in treating painful or stress-related conditions, biofeedback helps a patient control physiological processes that are normally considered involuntary. In biofeedback training, electronic or mechanical instruments attached to the patient measure physical functioning, such as the degree of muscle tension. The machines then transform this information into amplified signals that the patient can hear or see—for example, a beep or a flashing light—thus enabling the patient to know when internal responses are abnormal. This feedback information (see Automation ) can then guide the patient in trying to gain control over the internal condition. Biofeedback learning has been likened to that involved in mastering an athletic skill. Although this kind of learning may occur in biofeedback, its benefits often are largely the result of relaxation induced by the procedu

Fatigue

Fatigue (physiology), exhaustion of mind or body resulting from labor or exertion. Certain diseases, such as diabetes , cancer , and heart ailments, can also cause fatigue. Fatigue is characterized by the inability to perform physical tasks at one's usual pace or strength, and by a slowing of the thinking processes that may involve failure of memory. The term f atigue is also used to denote a decreased susceptibility of a sensory receptor, such as the eye, to sensation. A red surface seems to become gray when it is stared at continuously, and the retina is said to be fatigued by long exposure to the color red. The same is true of hearing. A prolonged noise that is heard continuously becomes less intense due to fatigue of the processes of the inner ear. Continued mental exertion, as in a protracted working over of a problem, causes the condition known as mental fatigue.

Alzheimer’s Disease

Alzheimer’s Disease, progressive brain disorder that causes a gradual and irreversible decline in memory , language skills, perception of time and space, and, eventually, the ability to care for oneself. First described by German psychiatrist Alois Alzheimer in 1906, Alzheimer’s disease was initially thought to be a rare condition affecting only young people, and was referred to as presenile dementia. Although Alzheimer’s disease is not a normal part of the aging process, the risk of developing the disease increases as people grow older. About 10 percent of the United States population over the age of 65 is affected by Alzheimer’s disease, and nearly 50 percent of those over age 85 may have the disease. Alzheimer’s disease takes a devastating toll, not only on the patients, but also on those who love and care for them. Some patients experience immense fear and frustration as they struggle with once commonplace tasks and slowly lose their independence. Family, friends, and especially th

Senile Dementia

Senile Dementia, form of general intellectual impairment observed in elderly people. Approximately 10 percent of all people more than 65 years of age have clinically important intellectual impairment. Although about 20 percent of these cases may be due to treatable causes such as toxic drug reactions, most cases are what is known as Alzheimer's disease . Senile dementia begins with failing attention and memory, loss of mathematical ability, irritability and loss of sense of humor, and poor orientation in space and time. Alzheimer's disease is relentlessly progressive and leads to death in 5 to 15 years. Examinations of the brains of persons who have died of Alzheimer's disease show characteristic twisted fibers, called neurofibrillary tangles, in certain areas of the brain, and cores of abnormal protein, called neuritic plaques, interspersed among nerve cells. No cure is known for Alzheimer's disease. A form of this disease strikes younger persons, in whom it is known a

Brain Diseases and Disorders

Brain disorders have a wide range of causes, including head injury, stroke, bacterial diseases, complex chemical imbalances, and changes associated with aging. Head Injury Head injury can initiate a cascade of damaging events. After a blow to the head, a person may be stunned or may become unconscious for a moment. This injury, called a concussion , usually leaves no permanent damage. If the blow is more severe and hemorrhage (excessive bleeding) and swelling occur, however, severe headache , dizziness, paralysis, a convulsion, or temporary blindness may result, depending on the area of the brain affected. Damage to the cerebrum can also result in profound personality changes. Damage to Broca's area in the frontal lobe causes difficulty in speaking and writing, a problem known as Broca's aphasia . Injury to Wernicke's area in the left temporal lobe results in an inability to comprehend spoken language, called Wernicke's aphasia. An injury or disturbance to a part of t

Memory

Memory (psychology), processes by which people and other organisms encode, store, and retrieve information. Encoding refers to the initial perception and registration of information. Storage is the retention of encoded information over time. Retrieval refers to the processes involved in using stored information. Whenever people successfully recall a prior experience, they must have encoded, stored, and retrieved information about the experience. Conversely, memory failure—for example, forgetting an important fact—reflects a breakdown in one of these stages of memory. TYPES OF MEMORY Although the English language uses a single word for memory, there are actually many different kinds. Most theoretical models of memory distinguish three main systems or types: sensory memory, short-term or working memory, and long-term memory. Within each of these categories are further divisions. Sensory Memory -> Sensory memory refers to the initial, momentary recording of information in our sensory s

Amnesia

Amnesia, loss or impairment of memory. Amnesia is usually associated with some form of brain damage, but it may also be caused by severe psychological trauma. Amnesia with a physical cause is called organic amnesia, whereas amnesia of psychological origin is called functional amnesia. Amnesia varies in its degree of severity. For example, a mild concussion may cause a person to forget recent events, but the memory loss may last only for several hours. On the other hand, severe head injuries may lead to permanent memory loss and an inability to learn new information. Amnesic individuals may retain normal cognitive abilities in other areas, such as language. Anterograde amnesia is impairment in the ability to lay down new memories. It typically results from damage to the areas of the brain involved in long-term memory, including the hippocampus, the temporal lobes, and the frontal lobes. Such damage may result from brain infection ( encephalitis ), alcoholism, stroke , anoxia (severe ox

Concussion of the Brain

Concussion of the Brain, injury to the brain from a fall or a blow to the head, usually with loss of consciousness, the reason for which is not entirely understood. Increased pressure on the brain stem probably accounts for the slowing or temporary suspension of respiration and the reduced pulse rate that accompany a concussion; additional symptoms include pallor, sweating, and a drop in blood pressure . Dizziness, nausea, and a dull, restless feeling often follow a return to consciousness. Aftereffects such as headaches, dizziness, and nervousness may continue for several days, weeks, or even years after the initial injury. A concussion may temporarily or permanently damage nerve tissue , producing amnesia , irritability, and fatigue ; memory is often impaired. Recovery from a concussion is generally complete and prompt after less severe injuries.

Headache

Headache, pain in any part of the head. Although the condition is widespread, less than 1 percent of all headaches indicate serious physical problems. This small percentage includes headaches caused by, or occurring after, concussion or injury to the head (see Concussion of the Brain ), meningitis , encephalitis , stroke , or brain tumors. Headache may also accompany misalignment of the jaw or teeth. Short-lived headaches may occur after eating very cold foods or foods high in nitrites or monosodium glutamate. Caffeine withdrawal also may provoke headaches. The majority of headaches belong to one of three main groups: migraine , a recurrent, severe headache, usually with throbbing on one side, accompanied by nausea and sometimes impaired vision; cluster, similar to migraine, but of short duration, occurring daily in series over weeks or months and predominantly in the area of one eye; and tension, a headache without consistent location thought to result from contractions of the face, s

Migraine

Migraine, severe headache that occurs periodically and is sometimes confined to only one side of the head. A migraine is characterized by intense, throbbing, often blinding pain, and one or more of the following symptoms: sensitivity to light, nausea, vomiting, chills, facial swelling, tenderness of the scalp, sweating, frequent urination, irritability, visual hallucinations, and malaise. The headache may be preceded by a warning sensation, known as an aura, that may include flashes or patterns before the eyes, illusory tastes or odors, dizziness, tingling, or numbness. At the onset of a migraine headache, blood vessels within the head constrict, causing a decrease in blood flow to the surface of the brain. Swelling of blood vessels in the head and scalp then sets off a chain of reactions that result in the headache. Among the biochemical changes associated with migraines are a reduced level of the neurotransmitter serotonin as well as an insufficient supply of enkephalins, the brain

Epilepsy

Epilepsy, also called seizure disorder, chronic brain disorder that briefly interrupts the normal electrical activity of the brain to cause seizures, characterized by a variety of symptoms including uncontrolled movements of the body, disorientation or confusion, sudden fear, or loss of consciousness. Epilepsy may result from a head injury, stroke, brain tumor, lead poisoning, genetic conditions, or severe infections like meningitis or encephalitis . DIAGNOSIS In persons suffering from epilepsy, the brain waves, electrical activity in the part of the brain called the cerebral cortex, have a characteristically abnormal rhythm produced by excessive electrical discharges in the nerve cells. Because these wave patterns differ markedly according to their specific source, a recording of the brain waves, known as an electroencephalogram (EEG) is important in the diagnosis and study of the disorder (see electroencephalography ). Diagnosis also requires a thorough medical history describing s

Cerebral Palsy

Cerebral Palsy, a range of neuromuscular disorders caused by injury to an infant's brain sustained during late pregnancy, birth, or any time during the first two years of life. People with cerebral palsy have a wide range of difficulties, from a clumsy walk to an inability to speak or swallow, caused by faulty messages sent from the brain to the muscles. In the mid-1800s, William Little, an English physician, first described cerebral palsy in connection with birth injuries. CAUSES Advances in diagnostic technology have led to a much better understanding of the causes of cerebral palsy. Over half of the cases are now thought to be due to prenatal causes such as an infection that spreads from the mother to the fetus, maternal stroke that prevents proper blood supply to the fetus, exposure to environmental toxins, or problems in brain development. The remaining cases are due to adverse events such as traumatic birth delivery, premature birth and its complications, meningitis (infecti

Disorders of the Nervous System

Consideration of disorders of the nervous system is the province of neurology; psychiatry deals with behavioral disturbances of a functional nature. The division between these two medical specialties cannot be sharply defined, because neurological disorders often manifest both organic and mental symptoms. For a discussion of functional mental illness, Mental Illness . Diseases of the nervous system include genetic malformations, poisonings, metabolic defects, vascular disorders, inflammations , degeneration, and tumors, and they involve either nerve cells or their supporting elements. Vascular disorders, such as cerebral hemorrhage or other forms of stroke , are among the most common causes of paralysis and other neurologic complications. Some diseases exhibit peculiar geographic and age distribution. In temperate zones, multiple sclerosis is a common degenerative disease of the nervous system, but it is rare in the Tropics. The nervous system is subject to infection by a great variet

Treatment of Kidney Diseases and Disorders

Treatment of severe kidney disease may include kidney dialysis , a procedure in which blood is circulated through a machine that removes wastes and excess fluid from the bloodstream. Some patients use dialysis for a short time, while their kidneys recover from injury or disease. Others must use dialysis for their entire lives or until they undergo a kidney transplant. Kidney transplants are the most common of all transplant operations and have excellent success rates (see Medical Transplantation ).

Kidney Dialysis

Kidney Dialysis, also known as hemodialysis, medical treatment used to remove waste materials from the blood of patients lacking renal function (see Kidney ). Blood from an artery is pumped through a dialyzer, or artificial kidney, where it flows past a semipermeable membrane . Dialysis fluid passing on the other side of the membrane removes unwanted elements in the blood by diffusion . The blood is then returned to the body through a vein . See also Treatment of Kidney Diseases and Disorders

Uremia

Uremia, presence in the bloodstream of too many chemical wastes such as urea , a nitrogen-rich waste product attributable to extra protein in the diet. As chemical wastes build up in the body they produce a toxic effect, possibly resulting in drowsiness, irritability, nausea, vomiting, breathlessness, headaches, and muscle cramps. In extreme cases, uremia may cause convulsions, coma , or death. The kidneys normally filter chemical wastes from the blood and send them to the urinary system for elimination from the body. Uremia most commonly develops when the kidneys fail to function properly. In some cases, however, uremia occurs when blood flow to the kidneys is reduced due to severe bleeding, serious burns, or heart attack, or when more wastes are formed in the bloodstream as a result of traumatic injuries or large surgical incisions than can be removed by the kidneys. A kidney stone, a tumor in the urinary tract, or a severely enlarged prostate in males may also cause uremia. Victim

Encephalitis

Encephalitis, any infectious disease of the human central nervous system characterized by inflammation of the brain . The typical symptoms are headache , fever , and extreme lethargy, which lead eventually to coma ; double vision, delirium , deafness , and facial palsy often occur in the acute stage of the disease. Aftereffects of encephalitis may include deafness, epilepsy , and dementia. Several types of encephalitis are caused by viral infection of the central nervous system. These types fall into two main groups, primary neurotropic-virus infections (original virus infections in nerve tissues), and secondary infections occurring as complications of a primary virus infection elsewhere in the body. NEUROTROPIC-VIRUS ENCEPHALITIS This group comprises several epidemic diseases that primarily affect wild and domestic animals and birds. The disease is transmitted to humans from these animals by insect vectors. St. Louis encephalitis, first recognized in 1933 during an epidemic in S

Meningitis

Meningitis, inflammation of the meninges, the membranes that surround the brain and spinal cord . Meningitis may be caused by a physical injury, a reaction to certain drugs, or more commonly, infection by certain viruses , bacteria , fungi , or parasites . This article focuses on meningitis caused by viral or bacterial infection. The most common causes of viral meningitis are coxsackie viruses and echoviruses, although herpesviruses, the mumps virus, and many other viruses can also cause the disease. Viral meningitis is rarely fatal, and most patients recover from the disease completely. Most cases of bacterial meningitis are caused by one of three species of bacteria— Haemophilus influenzae , Streptococcus pneumoniae , and Neisseria meningitidis . Many other bacteria, including Escherichia coli and the bacteria that are responsible for tuberculosis and syphilis, can also cause the disease. Bacterial meningitis can be fatal if not treated promptly. Some children who survive the infec

Death and Dying

Death and Dying, the irreversible cessation of life and the imminent approach of death. Death involves a complete change in the status of a living entity—the loss of its essential characteristics. PHYSIOLOGY Death occurs at several levels. Somatic death is the death of the organism as a whole; it usually precedes the death of the individual organs, cells, and parts of cells. Somatic death is marked by cessation of heartbeat, respiration, movement, reflexes, and brain activity. The precise time of somatic death is sometimes difficult to determine, however, because the symptoms of such transient states as coma , faint (see Fainting ), and trance closely resemble the signs of death. After somatic death, several changes occur that are used to determine the time and circumstances of death. Algor mortis, the cooling of the body after death, is primarily influenced by the temperature of the immediate environment. Rigor mortis, the stiffening of the skeletal muscles, begins from five to ten ho

Hemorrhagic Strokes

Hemorrhagic strokes account for the remaining 20 percent of all strokes. They occur when weakened blood vessels within the brain rupture and bleed into the surrounding tissue. The escaped blood can compress or pinch nearby blood vessels, cutting off blood flow and depriving the surrounding tissue of oxygen. Though hemorrhagic strokes occur less frequently than ischemic strokes, they tend to affect larger areas of the brain. Symptoms of a hemorrhagic stroke may be more sudden and more severe, and these strokes carry a greater risk of death than ischemic strokes. Hemorrhagic strokes can result from an aneurysm , which develops when the wall of a blood vessel weakens and thins, ballooning outward. If left untreated, the aneurysm continues to expand and weaken, increasing the likelihood of rupture. Hemorrhagic strokes can also result from an arteriovenous malformation (AVM), a cluster of enlarged, structurally weak blood vessels that forms during fetal development or possibly at birth. The

Ischemic Strokes

Ischemic strokes, which account for about 80 percent of all strokes, are caused by an obstruction in an artery, generally one of the carotid arteries, the major arteries in the neck that carry oxygen-rich blood from the heart to the brain. The path to an ischemic stroke begins when atherosclerosis, in which fatty deposits build up on the inner wall of an artery , develops in one of the carotid arteries (see Arteriosclerosis ). As the fatty deposit grows, it narrows the space through which blood can flow. Atherosclerosis does not actually cause ischemic strokes, but it sets up the conditions that make them likely to occur. The actual obstruction that cuts off blood flow in an ischemic stroke is a blood clot. Often the obstruction develops by a process known as thrombosis , the formation of a clot inside a blood vessel. A clot is likely to form at the site of an atherosclerotic deposit because the deposit causes blood to flow in a turbulent, disorderly fashion. This turbulence can cause

Stroke

Stroke is a brain damage caused by a lack of blood flow to part of the brain. In order to perform its many functions and direct activities throughout the body—from walking to seeing to reasoning—the brain requires a constant supply of energy, provided by the oxygen and nutrients that are delivered by the flowing blood. If blood flow is restricted or cut off at any point between the heart and the brain, portions of the brain relying on blood from the obstructed blood vessel become deprived of oxygen. Brain cells are extremely sensitive to such oxygen deprivation, and if they are deprived of oxygen and nutrients for more than several minutes, they, in effect, starve to death. A stroke results in permanent damage to the brain tissue—and in many cases, permanent disability for the patient. For example, a patient who has had a stroke may develop paralysis on one or both sides of the body; have difficulty with walking, eating, or other daily activities; or lose the ability to speak or unde

Hypertension

Hypertension or High Blood Pressure, medical condition in which constricted arterial blood vessels increase the resistance to blood flow, causing an increase in blood pressure against vessel walls. The heart must work harder to pump blood through the narrowed arteries. If the condition persists, damage to the heart and blood vessels is likely, increasing the risk for stroke , heart attack, and kidney or heart failure. Often called the “silent killer,” hypertension usually causes no symptoms until it reaches a life-threatening stage. Physicians use two measurements to describe blood pressure. Systolic pressure measures blood pressure as the heart contracts to pump out blood. Diastolic pressure measures blood pressure as the heart relaxes to allow blood to flow into the heart. An instrument called a sphygmomanometer measures systolic and diastolic pressure using units of millimeters of mercury (abbreviated mm Hg). Blood pressure is classified in four categories: normal, prehypertensio

Blood Pressure

Blood Pressure, pressure of circulating blood against the walls of the arteries (blood vessels that carry blood from the heart to the rest of the body). Blood pressure is an important indicator of the health of the circulatory system . Any condition that dilates or contracts the arteries or affects their elasticity, or any disease of the heart that interferes with its pumping power, affects blood pressure. In a healthy human being, blood pressure remains within a certain average range. The complex nervous system mechanisms that balance and coordinate the activity of the heart and arterial muscles permit great local variation in the rate of blood flow without disturbing the general blood pressure. Hemoglobin , the iron-protein compound that gives blood its red color, also plays a role in regulating local variation in blood pressure. Hemoglobin carries nitric oxide, a gas that relaxes the blood vessel walls. Hemoglobin controls the expansion and contraction of blood vessels, and thus

First Aid

First Aid, emergency care for a victim of sudden illness or injury until more skillful medical treatment is available. First aid may save a life or improve certain vital signs including pulse, temperature, a patent (unobstructed) airway, and breathing. In minor emergencies, first aid may prevent a victim’s condition from worsening and provide relief from pain. First aid must be administered as quickly as possible. In the case of the critically injured, a few minutes can make the difference between complete recovery and loss of life. First-aid measures depend upon a victim’s needs and the provider’s level of knowledge and skill. Knowing what not to do in an emergency is as important as knowing what to do. Improperly moving a person with a neck injury, for example, can lead to permanent spinal injury and paralysis. Despite the variety of injuries possible, several principles of first aid apply to all emergencies. The first step is to call for professional medical help. Determine that the

Artificial Respiration

Artificial Respiration, forcing of air into and out of the lungs of one person by another person or by mechanical means. It is usually employed during suspension of natural respiration caused by disease, such as poliomyelitis or cardiac failure; by electric shock; by an overdose of depressive drugs such as morphine, barbiturates , or alcohol; or by suffocation resulting from drowning , breathing noxious gases, or blockage of the respiratory tract. If the brain is deprived of oxygen for five minutes, it may be permanently damaged; slightly longer periods without oxygen usually result in death. The exception is drowning in very cold water, in which the body's oxygen demand is greatly reduced; people have been revived after being submerged for one-half hour in cold water. In the mouth-to-mouth method the unconscious person is laid faceup with the head tilted as far back as possible to prevent the tongue from blocking the air passages. The victim's nose is then pinched shut, and

Theophylline

Theophylline, prescription drug used to treat asthma , a chronic disease of the respiratory system. It is also used to treat asthmalike symptoms in patients with emphysema , chronic bronchitis , and pulmonary (lung) disease. Theophylline is sometimes used to treat breathing problems in infants at risk for sudden infant death s yndrome (SIDS). As a bronchodilator, the drug works by relaxing constricted muscles of the lung’s bronchi, the two branches of the trachea (windpipe) that lead to the lungs. It also opens blood vessels in the lungs, improving circulation. Theophylline is available in capsule, tablet, and liquid form. All are taken orally, usually with food to prevent stomach irritation. Dosage in children under the age of 16 is based on body weight. Adult dosages usually start at 200 mg taken twice a day, which may be increased if needed. The maximum adult dose is 900 mg per day. Effectiveness is usually apparent within 48 to 72 hours. Patients with peptic ulcers, seizure disorde

Bronchodilator

Bronchodilator, any of a group of drugs that expand the air passages (bronchial tubes) of the lungs . Bronchodilators are used to treat asthma, bronchitis, emphysema, and other diseases that affect the lungs. They relieve symptoms such as wheezing, shortness of breath, and coughing, and restore the patient’s ability to breathe comfortably. Bronchodilators work in various ways. Some, such as albuterol, affect the sympathetic nervous system, dilating the walls of the bronchial tubes. Others, such as theophylline, interfere with the action of certain enzymes or cells within the lungs, relaxing the constricted muscles of the airway. Many bronchodilators are inhaled through the mouth, especially those that provide immediate relief from an asthma attack. Some are taken orally in tablet or liquid form while others are injected into the skin. Inhaled bronchodilators are often prescribed with a dosage of 1 or 2 inhalations up to 4 times per day. A typical tablet dosage is 2 to 4 mg taken 3 to

Medical Transplantation

Medical Transplantation, transfer of a living tissue or organ to an injured or ill person to restore health or reduce disability. Over the past 45 years, surgeons have made great strides in their ability to implant organs in people who are seriously ill. At least 21 different organs—such as hearts, livers, and kidneys—and tissues—such as corneas and bone marrow—can now be successfully transplanted into patients who can then expect to survive for years or even decades. Improved surgical techniques are partly responsible for the success of organ transplants, but a more important factor is the development of drugs that can suppress the body’s rejection of the implanted organ without also leaving the patient highly susceptible to infections. Kidneys are the most common organs to be transplanted. Kidneys remove waste products from the blood stream. If they fail, often as a result of diabetes mellitus or cancer , a person can die from the buildup of these toxic materials. The waste products

Hemophilia

Hemophilia, hereditary blood disease characterized by the inability of blood to clot, or coagulate, leading to hemorrhage , or excessive bleeding, even from minor injuries. The disease is caused by an insufficiency or absence of certain blood proteins , called factors, that participate in blood clotting. The most common form, hemophilia A, is observed in 80 percent of hemophiliacs and is caused by a lack of factor VIII; in the second most common, hemophilia B (Christmas disease), factor IX is missing. The severity of hemophilia varies greatly. The bleeding may occur as excessive bruising or persistent bleeding after a simple cut. Hemorrhaging into joints and muscles can be disabling. Before the advent of modern therapy, the chance of survival to adulthood was poor. About 80 percent of all cases of hemophilia have an identifiable family history of the disease; in other instances, it may be attributable to a spontaneous mutation of genes . Researchers recently discovered that the spon

Anemia

Anemia (Greek for “bloodlessness”), a blood condition involving an abnormal reduction in the number of red blood cells (erythrocytes) or in their hemoglobin content. These cells are the means by which oxygen is carried to the various parts of the body. People who are anemic develop symptoms caused by the inadequate delivery of oxygen to their body tissues. There are three primary causes of anemia: (1) reduced production of red blood cells, which may result from deficiency in nutrients or hormones, or from disease or other conditions; (2) excessive destruction of red blood cells, often a hereditary problem; and (3) excessive blood loss. The most common type of anemia is iron-deficiency anemia, which occurs when the body's need for iron increases, as during certain periods of childhood and in pregnancy, or when there is insufficient iron in the diet. Pernicious anemia, a chronic ailment that mostly affects people over 40, is a result of vitamin B 12 deficiency, often caused by decre

Leukemia

Leukemia, any of several types of cancers that affect blood cells, including oxygen-carrying red cells; certain infection-fighting white cells, such as granulocytes, macrophages and lymphocytes; and platelets, which aid in blood clotting. Blood cells are made in the bone marrow , the spongy tissue in the center of bones. A leukemia begins when an immature blood cell in the marrow, known as a progenitor cell, becomes cancerous, dividing uncontrollably and overriding the body’s normal restrictions on cell division. Over time, the marrow becomes crowded with cancerous cells, all of them descendants of the first abnormal cell. The malignant cells may also accumulate in a patient’s lymph nodes, spleen , and elsewhere. At the time of diagnosis, up to a trillion leukemic cells may be present in the body. The mass of leukemic cells in the marrow suppresses the production of healthy blood cells, giving rise to the symptoms typical of leukemia. Pale skin, fatigue, and shortness of breath are s

Rheumatology

Rheumatology is a sub-specialty in internal medicine and pediatrics, devoted to the diagnosis and therapy of rheumatic diseases. Rheumatologists mainly deal with clinical problems involving joints, soft tissues and allied conditions of connective tissues. The term rheumatology originates from the Greek word rheuma, meaning "that which flows as a river or stream" and the suffix -ology, meaning "the study of." Rheumatology is a rapidly evolving medical specialty; new scientific discoveries related to this specialty are largely related to better understanding of immunology of these disorders. Pathogenesis of major rheumatological disorders is now described as autoimmune disorders. Immunology explains pathogenesis and the characteristics of rheumatological disorders, and most of the new treatment modalities are based on immunology, better understanding of genetic basis of rheumatological disorders makes rheumatology a specialty rapidly developing as a medical specialty

Oncology

Oncology is the branch of medicine that studies tumors ( cancer ) and seeks to understand their development, diagnosis, treatment, and prevention. A medical professional who practices oncology is an oncologist. The term originates from the Greek onkos (ογκος), meaning bulk, mass, or tumor and the suffix -ology, meaning "study of". The oncologist often coordinates the multidisciplinary care of cancer patients, which may involve physiotherapy, counselling, clinical genetics, to name but a few. On the other hand, the oncologist often has to liaise with pathologists on the exact biological nature of the tumor that is being treated. Oncology is concerned with: The diagnosis of cancer Therapy (e.g., surgery, chemotherapy, radiotherapy and other modalities) Follow-up of cancer patients after successful treatment Palliative care of patients with terminal malignancies Ethical questions surrounding cancer care Screening efforts: of populations, or of the relatives of patients (in type

Nephrology

Nephrology (from Greek: nephros, "kidney"; and λόγος, logos, "speech" lit. "to talk about kidney") is a branch of internal medicine and pediatrics dealing with the study of the function and diseases of the kidney. Nephrology concerns itself with the diagnosis and treatment of kidney diseases, including electrolyte disturbances and hypertension, and the care of those requiring renal replacement therapy, including dialysis and renal transplant patients. Many diseases affecting the kidney are systemic disorders not limited to the organ itself, and may require special treatment. Examples include systemic vasculitides and autoimmune diseases such as lupus. For more information about Nephrology, read the full articles at Wikipedia.org

Endocrinology

Endocrinology is a branch of medicine dealing with disorders of the endocrine system and its specific secretions called hormones . Endocrinology is concerned with the study of the biosynthesis, storage, chemistry, and physiological function of hormones and with the cells of the endocrine glands and tissues that secrete them. For more information about the topic Endocrinology, read the full articles at Wikipedia.org.

Cardiology

Cardiology is the branch of internal medicine dealing with disorders of the heart and blood vessels. The field is commonly divided in the branches of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians specializing in this field of medicine are called cardiologists. Cardiologists should not be confused with cardiac surgeons who are surgeons who perform cardiac surgery - operative procedures on the heart and great vessels. For more information about the topic Cardiology, read the full articles at Wikipedia.org.

Gerontology

Gerontology is the study of the social, psychological and biological aspects of aging. It is distinguished from geriatrics, which is the branch of medicine that studies the disease of the elderly. Gerontology includes these and other endeavors: studying physical, mental, and social changes in people as they age; investigating the aging process itself (biogerontology); investigating the interface of normal aging and age-related disease (geroscience); investigating the effects of our aging population on society, including the fiscal effects of pensions, entitlements, life and health insurance, and retirement planning; applying this knowledge to policies and programs, including a macroscopic (i.e. government planning) and microscopic (i.e. running a nursing home) perspective. The multidisciplinary focus of gerontology means that there are a number of sub-fields, as well as associated fields such as psychology and sociology that also cross over into gerontology. However, that there is an o

Surgery

Surgery, branch of medicine concerned with treatment of diseases, deformities, and injuries through manual procedures called operations. Surgery can be used to repair broken bones, stop uncontrolled bleeding, remove injured or diseased tissue and organs, and reattach severed limbs. Exploratory surgery helps physicians diagnose conditions that cannot be detected by traditional tests. It allows for examination of internal organs for signs of disease. People have practiced surgery since ancient times, but it did not become a respected science until the 19th century. Increasing knowledge of the human body, the discovery of anesthesia (a loss of physical sensation that can be induced with drugs), and the use of germ-free, or sterile, operating procedures combined to make surgery a safe and effective method of medical treatment. In the 20th century advances in technology have helped the field of surgery grow at a rapid pace. Surgery is performed by specially trained medical physicians know

Endoscopy

Endoscopy, examination of internal body cavities using a specialized medical instrument called an endoscope. Physicians use endoscopy to diagnose, monitor, and surgically treat various medical problems. An endoscope is a slender, flexible tube equipped with lenses and a light source. It contains glass fibers that transmit light to illuminate the body part being viewed and fibers that reflect an image of the body part back to the viewer. The endoscope also has a channel through which surgeons can manipulate tiny instruments, such as forceps, surgical scissors, and suction devices. A surgeon introduces the endoscope into the body either through a body opening, such as the mouth or the anus, or through a small incision in the skin. During the endoscopic procedure, the surgeon may perform several tasks. The surgeon may look for visual evidence of the problem, such as ulceration or inflammation; collect a sample of tissue; remove problematic tissue, such as polyps; or photograph the area be