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There's only one group of people who really know what happens when you die: the dead. And since the dead won't be revealing their secrets anytime soon, it's up to scientists to explain what happens when a person dies. Death, just like life, is a process, scientists say. The first stage of this process is known as clinical death. It lasts from four to six minutes, beginning when a person stops breathing and the heart stops pumping blood. During this time, there may be enough oxygen in the brain that no permanent brain damage occurs. Other organs, such as the kidneys and eyes, also remain alive throughout clinical death.
Esophageal atresia is an abnormality, or birth defect, of the esophagus that occurs early in pregnancy, as the baby is developing. The esophagus forms in the first few months of fetal life as a long, hollow, continuous tube joining the mouth to the stomach. In newborns with this birth defect, formation of this continuous esophageal tube is interrupted. esophageal-artresia-2In most cases, two separate tubes are formed, an upper (proximal) tube connected to the mouth and a lower (distal) tube connected to the stomach. This seperated tubes are sealed off creating a pouch on either side; the gap between these pounches can be short or very long. Saliva can accumulate in the upper pouch as it cannot drain into the stomach.
A bowel obstruction happens when either your small or large intestine is partly or completely blocked. The blockage prevents food, fluids, and gas from moving through the intestines in the normal way. The blockage may cause severe pain that comes and goes. This topic covers a blockage caused by tumors, scar tissue, or twisting or narrowing of the intestines. It does not cover ileus, which most commonly happens after surgery on the belly (abdominal surgery). What causes a bowel obstruction? Tumors, scar tissue (adhesions), or twisting or narrowing of the intestines can cause a bowel obstruction. These are called mechanical obstructions . In the small intestine, scar tissue is most often the cause. Other causes include hernias and Crohn's disease, which can twist or narrow the intestine, and tumors, which can block the intestine. A blockage also can happen if one part of the intestine folds like a telescope into another part, which is called intussusception.
What could cause a blockage in the stomach? Mechanical causes of intestinal obstruction may include: Adhesions or scar tissue that forms after surgery. Foreign bodies (objects that are swallowed and block the intestines) Gallstones (rare) Hernias. Impacted stool. Intussusception (telescoping of one segment of bowel into another) Tumors blocking the intestines. Less common radiologic signs are seen in specific circumstances. Most closed-loop obstructions (75%) are caused by adhesions. A closed-loop obstruction occurs when a loop of bowel is not decompressed by the caudal passage of gas and fluid.
Papillary fibroelastoma is the third most common primary tumor of the heart and is most likely to involve the cardiac valves. Like myxomas, they arise from the endocardium in most patients and since these tumors are often incidental findings at echocardiography or autopsy, the true incidence is difficult to estimate. Most patients are older than 60 years, which also contrasts with myxomas. Papillary fibroelastomas can embolize, leading to severe neurological complications and therefore, surgical removal is advised, although there is controversy regarding small incidental lesions and the need for surgery.
Colonoscopy is a test that allows your doctor to look at the inner lining of your large intestine (rectum and colon). He or she uses a thin, flexible tube called a colonoscope to look at the colon. A colonoscopy helps find ulcers, colon polyps, tumors, and areas of inflammation or bleeding.
Osteoporosis, which literally means porous bone, is a disease in which the density and quality of bone are reduced. As bones become more porous and fragile, the risk of fracture is greatly increased. The loss of bone occurs silently and progressively. Often there are no symptoms until the first fracture occurs.
Coronary artery bypass grafting (CABG) is a type of surgery that improves blood flow to the heart. Surgeons use CABG to treat people who have severe coronary heart disease (CHD). CHD is a disease in which a waxy substance called plaque (plak) builds up inside the coronary arteries.
Here we’ll explain the symptoms of pancreatitis, how alcohol causes the condition and the other health problems it can lead to. You probably don’t pay much attention to your pancreas. But that small, tadpole-shaped organ behind your stomach and below your ribcage is pretty important. It produces two essential substances: digestive juices which your intestines use to break down food, and hormones that are involved in digestion, such as insulin, which regulates your blood sugar levels. Pancreatitis is when your pancreas becomes inflamed and its cells are damaged. Heavy drinking can cause pancreatitis. But if you drink within the government’s low risk unit guidelines, you should avoid upsetting this important organ.
Blood clotting, or coagulation, is an important process that prevents excessive bleeding when a blood vessel is injured. Platelets (a type of blood cell) and proteins in your plasma (the liquid part of blood) work together to stop the bleeding by forming a clot over the injury.
The external jugular vein receives the greater part of the blood from the exterior of the cranium and the deep parts of the face, being formed by the junction of the posterior division of the retromandibular vein with the posterior auricular vein.
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.
Cytoplasmic organelles are "little organs" that are suspended in the cytoplasm of the cell. Each type of organelle has a definite structure and a specific role in the function of the cell. Examples of cytoplasmic organelles are mitochondrion, ribosomes, endoplasmic reticulum, golgi apparatus, and lysosomes.
What is systemic lupus erythematosus? The immune system normally fights off dangerous infections and bacteria to keep the body healthy. An autoimmune disease occurs when the immune system attacks the body because it confuses it for something foreign. There are many autoimmune diseases, including systemic lupus erythematosus (SLE). The term lupus has been used to identify a number of immune diseases that have similar clinical presentations and laboratory features, but SLE is the most common type of lupus. People are often referring to SLE when they say lupus.
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.
Signs and symptoms of this condition typically appear around the age of 3 or 4 months, when babies start to sleep through the night and do not eat as frequently as newborns. Affected infants may have low blood sugar (hypoglycemia), which can lead to seizures. They can also have a buildup of lactic acid in the body (lactic acidosis), high blood levels of a waste product called uric acid (hyperuricemia), and excess amounts of fats in the blood (hyperlipidemia). As they get older, children with GSDI have thin arms and legs and short stature. An enlarged liver may give the appearance of a protruding abdomen. The kidneys may also be enlarged. Affected individuals may also have diarrhea and deposits of cholesterol in the skin (xanthomas).
The vast majority of glucocorticoid activity in most mammals is from cortisol, also known as hydrocortisone. Corticosterone, the major glucocorticoid in rodents, is another glucocorticoid. Cortisol binds to the glucocorticoid receptor in the cytoplasm and the hormone-receptor complex is then translocated into the nucleus, where it binds to its DNA response element and modulates transcription from a battery of genes, leading to changes in the cell's phenotype. Only about 10% of circulating cortisol is free. The remaining majority circulates bound to plasma proteins, particularly corticosteroid-binding globulin (transcortin). This protein binding likely decreases the metabolic clearance rate of glucocorticoids and, because the bound steroid is not biologically active, tends to act as a buffer and blunt wild fluctuations in cortisol concentration.