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Blood-brain barrier
Blood-brain barrier The protective membrane that separates circulating blood from brain cells.
RELATED TERMS--------------------------------------
Membrane
A flexible layer surrounding a cell, organelle (such as the nucleus), or other bodily structure. The movement of molecules across a membrane is strictly regulated in both directions.
Blood
The life-maintaining fluid which is made up of plasma, red blood cells (erythrocytes), white blood cells (leukocytes), and platelets; blood circulates through the body's heart, arteries, veins, and capillaries; it carries away waste matter and carbon dioxide, and brings nourishment, electrolytes, hormones, vitamins, antibodies, heat, and oxygen to the tissues.
Brain
"That part of the central nervous system that is located within the cranium (skull). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called ""hemispheres."" "
SIMILAR TERMS--------------------------------------
Blood
The life-maintaining fluid which is made up of plasma, red blood cells (erythrocytes), white blood cells (leukocytes), and platelets; blood circulates through the body's heart, arteries, veins, and capillaries; it carries away waste matter and carbon dioxide, and brings nourishment, electrolytes, hormones, vitamins, antibodies, heat, and oxygen to the tissues.
Blood agar
A mixture of blood and nutrient agar, used for the cultivation of many medically important microorganisms.
Blood bank
A place where blood is collected from donors, typed, separated into components, stored, and prepared for transfusion to recipients. A blood bank may be a separate free-standing facility or part of a larger laboratory in a hospital.
Blood blister
A blister full of blood due to a pinch, bruise or repeated friction.
Blood brain barrier
A protective barrier formed by the blood vessels and glia of the brain. It prevents some substances in the blood from entering brain tissue.
Blood cleaner
"A process designed to eliminate most pathogens -- viruses, bacteria and fungi -- from donated blood. The process is termed ""pathogen inactivation."" It depends upon the fact that three components of blood that are given in transfusions -- red blood cells to carry oxygen, platelets to help blood clot and plasma for clotting and other purposes -- do not contain DNA or RNA, the basic genetic materials of life, whereas viruses, bacteria and fungi do. Therefore inactivating DNA or RNA can selectively kill these pathogens while leaving the blood itself unharmed. "
Blood clot
A gelled mass of blood tissue.
Blood Clot (thrombus)
A clot forms when clotting factors in the blood cause it to coagulate or become a solid, jelly-like mass. When a blood clot forms inside a blood vessel (a thrombus), it can dislodge and travel through the blood stream, causing a heart attack or stroke.
Blood clots, estrogen-associated
Blood clots are occasional but serious side effects of estrogen therapy. They are dose-related, that is, they occur more frequently with higher doses of estrogen.
Blood count
The calculated number of white or red blood cells (WBCs or RBCs) in a cubic millimeter of blood.
Blood culture
A test designed to detect if microorganisms such as bacteria and fungi are present in blood. A sample of blood obtained using sterile technique is placed in a culture media and incubated in a controlled environment for 1 to 7 days. If microorganisms grow, they can be identified as to type and tested against different antibiotics for proper treatment of the infection. Because microorganisms may only be intermittently present in blood, a series of 3 blood cultures is usually done before the result is considered negative.
Blood draw
Removal of blood, usually by venipuncture (phlebotomy, venous blood sampling). Blood draw is a popular term that is coming into common usage both as an adjective and noun. Stanford University Medical Center has a number of blood draw sites. This morning I had a blood draw.
Blood dyscrasia
Blood disease.
Blood Glucose
The primary source of energy for the brain. Elevated blood glucose levels cause diabetes and accelerate aging.
Blood glucose
The main sugar that the body makes from the food in the diet. Glucose is carried through the bloodstream to provide energy to all cells in the body. Cells cannot use glucose without the help of insulin.
Blood Glucose Meter / Blood Glucose Monitoring
A way of testing how much glucose (sugar) is in the blood. A drop of blood, usually taken from the fingertip, is placed on he end of a specially coated strip, called a testing strip. The strip has a chemical on it that makes it change color according to how much glucose is in the blood. A person can tell if the level of glucose is low, high, or normal in one of two ways. The first is by comparing the color on the end of the strip to a color chart that is printed on the side of the test strip container. The second is by inserting the strip into a small machine, called a meter, which "reads" the strip and shows the level of blood glucose in a digital window display. Some meters have a memory that can store results from multiple tests. good testing is more accurate than urine testing in monitoring blood glucose levels because it shows what the current level of glucose is, rather than what the level was an hour or so previously.
Blood group
An inherited feature on the surface of the red blood cells. A series of related blood types constitute a blood group system such as the Rh or the ABO system.
Blood group, ABO
The major human blood group system. The ABO type of a person depends upon the presence or absence of two genes, A and B. These genes determine the configuration of the red blood cell surface.
Blood in semen
Blood in semen (ejaculate) is also called hematospermia. Blood in semen can be caused by many conditions affecting the tubes that distribute semen from the testicles (seminal vesicles) or the prostate gland. The most common cause of blood in semen is inflammation of the seminal vesicles or prostate gland. Blood in the semen can temporarily be caused by injury to the prostate gland, such as from prostate biopsy.
Blood in the eye
Medically known as a subconjunctival hemorrhage. A very common cause of a painless bloody eye usually first noticed by somebody else or by the person with it when they look in the mirror. The bleeding results from a break in a small blood vessel in the sclera, the white of the eye. This releases a tiny amount (less than a drop) of blood which is trapped underneath the conjunctiva, much like the blood in a bruise is trapped in the skin. It is called a subconjunctival hemorrhage since it occurs beneath the conjunctiva, the transparent membrane covering the sclera.
Blood in the urine
Blood in the urine is termed hematuria. Gross hematuria refers to blood that is so plentiful in the urine that the blood is visible grossly, with just the naked eye.
Blood pH
The acidity or alkalinity of blood. The pH of any fluid is the measure of the hydrogen ion (H-) concentration. A pH of 7 is neutral. The lower the pH, the more acidic the blood. A variety of factors affect blood pH including what is ingested, vomiting, diarrhea, lung function, endocrine function, kidney function, and urinary tract infection. The normal blood pH is tightly regulated between 7.35 and 7.45.
Blood poisoning
Infection within the circulatory system. A potentially life-threatening condition that requires prompt treatment.
Blood pressure
The force or pressure exerted by the heart when pumping blood; also, the pressure of blood in the arteries.
Blood Pressure
The force of the blood on the walls of arteries. Two levels of blood pressure are measured-the higher, or systolic, pressure, which occurs each time the heart pushes blood into the vessels, and the lower, or diastolic, pressure, which occurs when the heart rests. In a blood pressure reading of 120/80, for example, 120 is the systolic pressure and 80 is the diastolic pressure. A reading of 120/80 is said to be the normal range. Blood pressure that is too high can cause health problems such as heart attacks and strokes.
Blood pressure cuff
A device usually placed around the upper of the arm to measure blood pressure.
Blood pressure, high
Also known as hypertension, high blood pressure is, by definition, a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90.
Blood pressure, low
Any blood pressure that is below the normal expected for an individual in a given environment. Low blood pressure is also referred to as hypotension.
Blood sugar
Blood glucose.
Blood sugar, high
An elevated level of the sugar glucose in the blood. Also called hyperglycemia.
Blood sugar, low
The sugar here is glucose. Low blood glucose constitutes hypoglycemia. Hypoglycemia is only significant when it is associated with symptoms. It has many causes including drugs, liver disease, surgical absence of the stomach, pre-diabetes, and rare tumors that release excess insulin.
Blood Thinners (anticoagulants)
Medicine used to prevent clots from forming or getting larger. Heparin is generally given through the vein and Coumadin (warfarin) by mouth.
Blood transfusion
The transfer of blood or blood components from one person (the donor) into the bloodstream of another person (the recipient). This may be done as a lifesaving maneuver to replace blood cells or blood products lost through bleeding. Transfusion of your own blood (autologous) is the safest method but requires advance planning and not all patients are eligible. Directed donor blood allows the patient to receive blood from known donors. Volunteer donor blood is usually most readily available and, when properly tested has a low incidence of adverse events. Blood conserving techniques are an important aspect of limiting transfusion requirements.
Blood Typing
A test that can help establish compatibility between two different types of blood. Blood types include A, B, AB or O.
Blood urea nitrogen
Abbreviated BUN. A measure primarily of the urea level in blood. Urea is cleared by the kidney. Diseases that compromise the function of the kidney frequently lead to an increased BUN.
Blood Urea Nitrogen (BUN)
A waste product of the kidneys. Increased levels of BUN in the blood may indicate early kidney damage.
Blood Vessels
Tubes that act like a system of roads or canals to carry blood to and from all parts of the body. The three main types of blood vessels are arteries, veins, and capillaries. The heart pumps blood through these vessels so that the blood can carry with it oxygen and nutrients that the cells need or take away waste that the cells do not need.
Blood, urinary
Medically called hematuria, blood in the urine can be microscopic or gross. Evaluating hematuria requires consideration of the entire urinary tract. Tests used for the diagnosis of hematuria include the intravenous pyelogram (IVP), cystoscopy, and urine cytology. Management of hematuria depends upon the underlying cause.
Blood-Sampling Devices
A small instrument for pricking the skin with a fine needle to obtain a sample of blood to test for glucose (sugar).
Blood-thinner
A common name for an anticoagulant agent used to prevent the formation of blood clots. Blood-thinners do not really thin the blood. They prevent it from clotting.
Bloody nose
"The nose is a part of the body that is very rich in blood vessels (vascular) and is situated in a vulnerable position on the face. As a result, any trauma to the face can cause bleeding which may be profuse. Nosebleeds can occur spontaneously when the nasal membranes dry out, crust, and crack, as is common in dry climates, or during the winter months when the air is dry and warm from household heaters. People are more susceptible if they are taking medications which prevent normal blood clotting (Coumadin, warfarin, aspirin, or any anti-inflammatory medication). Other predisposing factors include infection, trauma, allergic and non-allergic rhinitis, hypertension, alcohol abuse, and inherited bleeding problems. To stop a nosebleed, you should: 1. Pinch all the soft parts of the nose together between your thumb and index finger. 2. Press firmly toward the face - compressing the pinched parts of the nose against the bones of the face. 3. Hold the nose for at least 5 minutes (timed by the clock). Repeat as necessary until the nose has stopped bleeding. 4. Sit quietly, keeping the head higher than the level of the heart; that is, sit up or lie with the head elevated. Do not lay flat or put your head between your legs. 5. Apply ice (crushed in a plastic bag or washcloth) to nose and cheeks. "
Bloody show
The discharge - often mucus tinged with blood - that appears as labor approaches. Sometimes refers to light bleeding, other times is used to mean the mucus plug that dislodges when the cervix begins to efface and/or dilate.
Bloody sputum
Spitting up blood or bloody mucus. Bloody sputum can come from common forms of infection in the lungs and airways, such as acute bronchitis or pneumonia. Whenever bloody sputum is present and cannot be attributed to one of these curable conditions, a complete lung evaluation is warranted, including bronchoscopy. Bloody sputum is also referred to as hemoptysis.
Bloomfield Hospital
The Bloomfield Hospital is a hospital in Wellington, New Zealand.
Bloomington Hospita
Bloomington Hospita is a hospital in Bloomington, Indiana (USA).
Bloomington Hospital
The Bloomington Hospital is a hospital in Bloomington, Indiana, United States.
PREVIOUS AND NEXT TERMS--------------------------------------
Bone marrow harvest
A procedure to collect healthy bone marrow which will be stored and used in a future bone marrow transplant.
Bone marrow transplant (BMT)
A procedure to replace a patient's diseased or treatment-damaged bone marrow with healthy marrow. The new marrow can be marrow that has been previously removed from the patient and stored until needed (autologous transplant); or marrow that is donated either from a genetically matched relative or unrelated donor (allogeneic transplant) or from the patient's genetically identical twin (syngeneic transplant).
Basal ganglia
Several large clusters of nerve cells, including the striatum and the substantia nigra, deep in the brain below the cerebral hemispheres.
Bell's palsy
An unexplained episode of facial muscle weakness or paralysis that begins suddenly and steadily worsens.
Blink rate
The number of times per minute that the eyelid automatically closes -- normally 10 to 30 per minute.
Blood-brain barrier
Bradykinesia
Slowness of movement.
Bradyphrenia
Slowness of thought processes.
Brain attack
Also called "stroke". Happens when brain cells die because of inadequate blood flow.
Base (dentistry)
The dentistry sense of base is cement placed under a dental restoration to insulate the pulp (nerve chamber)
Bicuspid or pre-molar
Transitional teeth behind the cuspids.
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