The human immunodeficiency virus -- HIV -- causes acquired immunodeficiency syndrome, or AIDS. You can be infected with HIV for many years and show few if any symptoms before the development of AIDS. However, people who are HIV-infected can transmit the virus to other people.
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The amount of urine your body produces in a day can be directly related to your health. The kidneys' main function is to maintain the correct balance of water and various chemicals in your blood.
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Sodium is an electrolyte that helps regulate blood pressure and fluid levels in your body; it also plays a role in the normal function of nerves and muscles. A blood sodium level below 135 mmol/L is considered low.
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White blood cells (WBCs) are the foot soldiers of the immune system. They help fight infections, limit injury from other harmful substances, and initiate healing if tissue damage occurs. WBCs are made and primarily stored in the bone marrow.
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The 3 classic symptoms of diabetes mellitus are polyuria, polydipsia and polyphagia -- also known as the 3 P's. Polyuria, polydipsia and polyphagia are defined as an increase in urination, thirst and hunger, respectively. The presence of the 3 P’s is a good indication that your blood sugar may be too high.
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Uric acid is formed in the body from the normal breakdown of chemicals called purines, which arise from normal DNA and RNA turnover, from molecules that are the source of energy in cells or from dietary sources. A higher than normal blood uric acid level is called hyperuricemia.
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Vitamin B12, or cobalamin, is important for the development of healthy red blood cells and proper nervous system function. The main dietary sources of vitamin B12 include meat, dairy and fish. While doctors are often more concerned with low vitamin B12 levels, high levels might also signal a serious medical problem.
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Bilirubin is a byproduct of normal hemoglobin breakdown. When old red blood cells are broken down, the hemoglobin within them is converted into bilirubin. The liver then degrades bilirubin into bile and either stores it in the gallbladder or excretes it through the stool.
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Blood sugar, or glucose, serves as the fuel your body uses to generate energy. The level of glucose in your blood remains fairly stable, slightly rising after eating and declining a small amount between meals or after exercising. Blood glucose can be measured in many ways.
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Alkaline phosphatase is an enzyme found in many organs, including the liver, bone, kidney, intestine and placenta. The highest concentration of alkaline phosphatase comes from the liver and bone. A routine blood test detects the total amount of alkaline phosphatase in the blood.
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As your child grows, it's important to know if he is healthy and growing as expected. Comparing your baby's weight to an expected weight is one way to ensure your child is growing well. Pediatricians use growth charts to accomplish this.
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Human chorionic gonadotropin, or hCG, is a hormone made by the placenta to help support the growth of the fetus during pregnancy. During normal pregnancy, hCG levels generally double about every 48 to 72 hours and can be detected by a blood test about 3 weeks from the last menstrual period.
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Platelets are small cell fragments found in your blood that are responsible for helping blood clot. They release chemicals that signal for blood to clot, as well as stick together to form a plug to stop bleeding. Normal platelet counts generally range from 150,000 to 400,000 per milliliter, or mL, of blood.
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Bacteria are microscopic single-celled organisms that are all around us. They come in many different sizes and shapes, and this is a common way to classify them—by their morphology, or shape and appearance. The three basic shapes of bacteria are spherical, rod shaped and spiral.
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Human chorionic gonadotropin, or hCG, is a hormone most commonly associated with pregnancy. In females, hCG is typically made in large amounts by the placenta during pregnancy and is detected by a blood or urine test to confirm pregnancy.
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Simple squamous epithelium refers to a single layer of thin, flat cells that line body surfaces. One side of the surface opens to the environment while the other is anchored to the underlying cells.
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Diabetes mellitus is a metabolic disorder in which inadequate production of the hormone insulin or a resistance to its actions in the body can lead to high blood sugar levels. Insulin is needed to get sugar into cells of the body, where it is used for energy.
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As part of a urinalysis test, urine may be examined under a microscope to check for the presence of crystals. Urine contains many chemicals, some of which can form solid particles, or crystals, under certain conditions.
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Iron is a nutrient found in your body that comes entirely from your diet. It is found in fortified cereal, meat, beans and leafy green vegetables. Iron is necessary to make red blood cells and carry oxygen. Most of the iron in the body is found in red blood cells.
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