36 résultats pour "disorders"
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Personality Disorders.
People with histrionic personality disorder constantly strive to be the center of attention. They may act overly flirtatious or dress in ways that draw attention. They may also talk in a dramatic or theatrical style and display exaggerated emotional reactions. F Narcissistic Personality Disorder People with narcissistic personality disorder have a grandiose sense of self-importance. They seek excessive admiration from others and fantasize about unlimited success or power. They believe they...
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Anxiety.
A Genetics and Neurobiology Studies suggest that anxiety disorders run in families. That is, children and close relatives of people with disorders are more likely than most to develop anxietydisorders. Some people may inherit genes that make them particularly vulnerable to anxiety. These genes do not necessarily cause people to be anxious, but the genesmay increase the risk of anxiety disorders when certain psychological and social factors are also present. Anxiety also appears to be related to...
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Mental Illness.
note that under this definition, political dissidents could be considered mentally ill for refusing to accept the dictates of their government. VI PREVALENCE Mental illness affects people of all ages, races, cultures, and socioeconomic classes. The prevalence of mental illness refers to how many people experience a mentalillness during a specified time period. A United States and Worldwide In the United States, researchers estimate that about 24 percent of people 18 or older, or about 44 mill...
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Psychology.
Clinical psychology is dedicated to the study, diagnosis, and treatment of mental illnesses and other emotional or behavioral disorders. More psychologists work in this field than in any other branch of psychology. In hospitals, community clinics, schools, and in private practice, they use interviews and tests to diagnose depression,anxiety disorders, schizophrenia, and other mental illnesses. People with these psychological disorders often suffer terribly. They experience disturbing symptoms t...
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Alcoholism.
Although a consensus is growing among health professionals that alcohol dependence is a disease, society’s attitudes toward individuals with drinking problems remainambivalent and confused. Until the mid-20th century, the typical picture of the alcoholic was of someone without steady employment, unable to sustain familyrelationships and most likely in desperate financial straits. But this stereotype was largely dispelled when highly respected people publicly admitted their alcoholdependence and...
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Stress (psychology).
blood flow is diverted from the internal organs and skin to the brain and muscles. Breathing speeds up, the pupils dilate, and perspiration increases. This reaction issometimes called the fight-or-flight response because it energizes the body to either confront or flee from a threat. Another part of the stress response involves the hypothalamus and the pituitary gland, parts of the brain that are important in regulating hormones and many otherbodily functions. In times of stress, the hypothal...
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Human Disease.
disease can be transmitted through food infected with mutated proteins. B Spread of Infectious Disease Some pathogens are spread from one person to another by direct contact. They leave the first person through body openings, mucous membranes, and skin wounds,and they enter the second person through similar channels. For example, the viruses that cause respiratory diseases such as influenza and the common cold are spreadin moisture droplets when an infected person coughs or sneezes. A hand that...
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Autism.
may also repeat body movements, such as spinning, rocking, or flapping hands. When upset or excited, they may also harm themselves by skin-biting or head-banging. They may also show significant aggression toward other people or inanimateobjects, or may have episodes of extreme anger or frustration. D Associated Symptoms Some children with autism show other symptoms that do not contribute to the diagnosis of autism itself. Sensory sensitivity is quite common, especially to some textures, sounds,...
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Endocrine System.
thermostat. When the heat in a house falls, the thermostat responds by switching the furnace on, and when the temperature is too warm, the thermostat switches thefurnace off. Usually, the change that a hormone produces also serves to regulate that hormone's secretion. For example, parathyroid hormone causes the body toincrease the level of calcium in the blood. As calcium levels rise, the secretion of parathyroid hormone then decreases. This feedback mechanism allows for tight controlover hormon...
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Sleep - biology.
V FUNCTIONS OF SLEEP Although no one knows for sure why we sleep, there are a number of theories. Sleep may have evolved to protect animals from their predators by reducing theiractivity during the times when they are most vulnerable. Research has shown that REM and NREM sleep may serve specific biological functions. Sleep deprivation studies reveal that humans and other animals respond to sleeploss in the same way. When study subjects are deprived of REM sleep, they tend to spend longer period...
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Eye.
I
INTRODUCTION
Eye, light-sensitive organ of vision in animals. The eyes of
Several structures, not parts of the eyeball, contribute to the protection of the eye. The most important of these are the eyelids, two folds of skin and tissue, upper andlower, that can be closed by means of muscles to form a protective covering over the eyeball against excessive light and mechanical injury. The eyelashes, a fringe ofshort hairs growing on the edge of either eyelid, act as a screen to keep dust particles and insects out of the eyes when the eyelids are partly closed. Inside the...
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Heredity - biology.
allele from the mother and a mutated allele from the father. In both of these cases, the child will be a carrier. The child develops the disease only if he or she receives amutated allele from each parent. When both parents are carriers, there is a 25 percent chance that a child will be disease-free, a 25 percent chance that it will have thedisease, and a 50 percent chance that it will be a carrier. Examples of genetic diseases that follow the dominant-recessive pattern include sickle-cell anemi...
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Attention-Deficit Hyperactivity Disorder.
Although the drugs are prescribed most often to treat ADHD among children, increasingly adults are taking the drugs for ADHD. From 2002 to 2005 the number ofprescriptions written for adults reportedly increased by 90 percent. In the United States about 2.5 million children and about 1.5 million adults take ADHD drugs. Amember of the FDA advisory panel noted that adults are more likely to have a higher risk of heart problems. Most of the 25 sudden deaths, however, were amongchildren. The prelimin...
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Suicide.
C Sociological Theories Most social scientists believe that a society’s structure and values can influence suicide rates. French sociologist Émile Durkheim argued that suicide rates are related tosocial integration —that is, the degree to which an individual feels part of a larger group. Durkheim found suicide was more likely when a person lacked social bonds or had relationships disrupted through a sudden change in status, such as unemployment. As one example of the significance of social bond...
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Parkinson Disease.
III SYMPTOMS Parkinson disease most notably affects motor control (muscle activity). The disease progresses differently for each individual—symptoms develop swiftly in some peopleand slowly in others. Some Parkinson patients may develop problems that affect their intellect or ability to reason, or they may suffer from depression or anxiety. A Motor Control Problems Doctors look for the presence of four principal symptoms in patients they suspect may have Parkinson disease. Tremor (the involun...
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Child Abuse.
C Social Isolation and Low Community Involvement Parents and caretakers who abuse children tend to be socially isolated. Few violent parents belong to any community organizations, and most have little contact withfriends or relatives. This lack of social involvement deprives abusive parents of support systems that would help them deal better with social or family stress. Moreover,the lack of community contacts makes these parents less likely to change their behavior to conform with community va...
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Diabetes Mellitus.
Once diabetes is diagnosed, treatment consists of controlling the amount of glucose in the blood and preventing complications. Depending on the type of diabetes, thiscan be accomplished through regular physical exercise, a carefully controlled diet, and medication. Individuals with Type 1 diabetes must receive insulin, often two to four times a day, to provide the body with the hormone it does not produce. Insulin cannot be takenorally, because it is destroyed in the digestive system. Consequent...
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Psychotherapy.
Other managed-care companies pay therapists a set fee to meet with a client for up to a specified maximum number of sessions depending on the nature of theproblem, free of interference from case reviewers. For example, a managed-care firm may pay a therapist $200 to hold up to eight sessions with a person. If the clientuses all eight sessions, the therapist normally loses money. But if treatment stops after two or three sessions, the therapist makes a profit. This relatively new system iscontrov...
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Mental Retardation.
For example, measles, chicken pox, and whooping cough may lead to encephalitis and meningitis, which can damage the brain. Physical trauma to the brain can also cause mental retardation. Brain damage may result from accidental blows to the head, near drowning, severe child abuse, andchildhood exposure to such toxins as lead and mercury. Experts believe that poverty and a lack of stimulation during infancy and early childhood can be factors inmental retardation. Children raised in poor environmen...
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Nervous System.
of paralysis and other neurologic complications. Some diseases exhibit peculiar geographic and age distribution. In temperate zones, multiple sclerosis is a commondegenerative disease of the nervous system, but it is rare in the Tropics. The nervous system is subject to infection by a great variety of bacteria, parasites, and viruses. For example, meningitis, or infection of the meninges investing thebrain and spinal cord, can be caused by many different agents. On the other hand, one specific v...
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Sigmund Freud.
reminiscences from the past and about her daydreams. Remarkably, as her narrative revisited memories from the past, which were associated with the onset of aparticular symptom, each symptom disappeared when accompanied by an emotional outburst. Breuer made use of this discovery to eliminate her symptoms one at atime. He called the treatment the cathartic technique (from the Greek katharsis meaning “purgation”). The treatment was time consuming and required considerable effort to reach dimly re...
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La Psychiatrie est elle une science?
distinguish science from non-science. Philosophers of science now generally agree that the search for a demarcation criterion has failed. However, in other disciplines the search for a means of distinguishing science from pseudoscience continues. I review the current debate in psychology and psychiatry. Then, returning to philosophical work, I discuss and support accounts according to which 'science' is best considered a family resemblance term. This suggests that whether psychiatric research is...
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Digestive System.
The stomach, located in the upper abdomen just below the diaphragm, is a saclike structure with strong, muscular walls. The stomach can expand significantly to storeall the food from a meal for both mechanical and chemical processing. The stomach contracts about three times per minute, churning the food and mixing it with gastricjuice. This fluid, secreted by thousands of gastric glands in the lining of the stomach, consists of water, hydrochloric acid, an enzyme called pepsin, and mucin (the...
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Depression (psychology).
IV CAUSES Some depressions seem to come out of the blue, even when things are going well. Others seem to have an obvious cause: a marital conflict, financial difficulty, or somepersonal failure. Yet many people with these problems do not become deeply depressed. Most psychologists believe depression results from an interaction betweenstressful life events and a person’s biological and psychological vulnerabilities. A Biological Factors Depression runs in families. By studying twins, researche...
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Immune System.
The humoral immune response involves a complex series of events after antigens enter the body. First, macrophages take up some of the antigen and attach it to classII MHC molecules, which then present the antigen to T helper cells. The T helper cells bind the presented antigen, which stimulates the T helper cells to divide andsecrete stimulatory molecules called interleukins. The interleukins in turn activate any B lymphocytes that have also bound the antigen. The activated B cells then divide...
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Police.
body. In larger agencies, executive officers may be selected through a civil service or merit system, after moving through the ranks from patrol officer to sergeant,lieutenant, captain, and (in still larger agencies) deputy or assistant chief. At the county level, the head of the agency usually holds the title sheriff. The sheriff is almost always elected and has the power to appoint deputies. Sheriffs'departments often provide law enforcement services for unincorporated areas of counties and ar...
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Circulatory System.
C Additional Functions In addition to oxygen, the circulatory system also transports nutrients derived from digested food to the body. These nutrients enter the bloodstream by passingthrough the walls of the intestine. The nutrients are absorbed through a network of capillaries and veins that drain the intestines, called the hepatic portal circulation.The hepatic portal circulation carries the nutrients to the liver for further metabolic processing. The liver stores a variety of substances, suc...
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Vitamin.
Vitamin B 1, or thiamine, promotes the metabolism of carbohydrates, enabling these nutrients to release their energy. Thiamine also plays a role in the functioning of the nervous system, muscles, and heart. The body does not store thiamine and people who are malnourished may develop thiamine deficiency. Mild thiamine deficiency cancause fatigue, muscle weakness, and loss of appetite. Severe thiamine deficiency causes beriberi, a disease characterized by muscle weakness, swelling of the heart,and...
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Lung.
I
INTRODUCTION
Lung, either of a pair of elastic, spongy organs used
lead to emphysema, which is caused by wholesale destruction of alveoli. Other lung disorders include pneumonia, or inflammation of the lungs, which is usually causedby viruses or bacteria; pneumothorax, or collapse of the lung; pulmonary edema, or fluid in the lung; and pleural effusion, or fluid on the pleura. Pulmonary embolismoccurs when a blood clot or other foreign substance lodges in the lungs and blocks the major pulmonary arteries. Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corp...
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Genetics - biology.
construct identical buildings. Just as each contractor would require a full copy of the blueprint to construct a complete building, each new cell needs a complete copy ofan organism’s genetic information to function properly. Organisms use two types of cell division to ensure that DNA is passed down from cell to cell during reproduction. Simple one-celled organisms and other organisms thatreproduce asexually—that is, without the joining of cells from two different organisms—reproduce by a proces...
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Kidney.
secretion. An additional function of the kidney is the processing of vitamin D; the kidney converts this vitamin to an active form that stimulates bone development. Several hormones are produced in the kidney. One of these, erythropoietin, influences the production of red blood cells in the bone marrow. When the kidney detectsthat the number of red blood cells in the body is declining, it secretes erythropoietin. This hormone travels in the bloodstream to the bone marrow, stimulating theproducti...
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Alternative Medicine.
The field of chiropractic was founded by David Daniel Palmer in the 1890s. He believed that joint subluxation, or a partial dislocation, is a causal factor in disease andthat removal of the subluxation by thrusting on the bony projections of the vertebrae restores health. In addition to manipulating and adjusting bone and tissue, particularly in the spinal column, chiropractors use a variety of manual, mechanical, and electrical treatments.Chiropractors are most widely recognized for providing d...
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Alzheimer's Disease.
compared residents of Ibadan, Nigeria, who eat a mostly low-fat vegetarian diet, with African Americans living in Indianapolis, Indiana, whose diet included a variety ofhigh-fat foods. The Nigerians were less likely to develop Alzheimer’s disease compared to their U.S. counterparts. Some researchers suspect that health problems suchas high blood pressure, atherosclerosis (arteries clogged by fatty deposits), high cholesterol levels, or other cardiovascular problems may play a role in the devel...
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Teeth.
treatments to reduce the risk of tooth decay; clear plastic coatings painted on the teeth, called dental sealants, and applications of the mineral fluoride, which fortifiestooth enamel, are two such treatments. Fluoride is also added to public water supplies in a process called fluoridation, which benefits more than 150 million Americans. Gum disease, or periodontal disease, is a progressive condition that worsens with age. Gum disease occurs when bacteria eat away at gum tissue, causing it to p...
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Diseases of Animals.
infected animal. It may also spread in milk or in garbage that contains contaminated meat. Typical symptoms include blisters that appear on the mouth and feet;animals may become lame when their hooves degenerate. Canine distemper is a highly contagious disease caused by the paramyxovirus, which is transmitted in discharges from the nose and eyes. Symptoms begin with fever,malaise, and nasal and ocular discharges and may progress to convulsions and other nervous system disorders. Parvoviruses aff...
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Ear.
I
INTRODUCTION
Ear, organ of hearing and balance. Only vertebrates, or animals
line or rotates in any direction. Each canal also contains sensory areas with sensory hair cells that project into a cone-shaped cap of gelatin. Two of the semicircularcanals are in a vertical position and are used to detect vertical movement, such as jumping or falling. The third canal is horizontal and detects horizontal movement,such as turning or spinning. The action of the canals depends on the inertia of the fluid inside. When the motion of the body changes, the fluid lags behind, causing...