What is myositis? Myositis means muscle inflammation, and can be caused by infection, injury, certain medicines, exercise, and chronic disease. Some of the chronic, or persistent, forms are idiopathic inflammatory myopathies, and those are the diseases we discuss here. "Idiopathic" means that the cause is unknown.

Dextrocardia situs inversus refers to the heart being a mirror image situated on the right side. For all visceral organs to be mirrored, the correct term is dextrocardia situs inversus totalis. Dextrocardia is believed to occur in approximately 1 in 12,000 people.

Bone is not a static part of the body — it's constantly being resorbed (broken down) and formed throughout your life. Your entire skeleton is replaced about every decade, according to the NIH. During your childhood and teenage years, bone formation occurs more quickly than bone resorption, resulting in growth. You reach your maximum bone density and strength around age 30, after which bone resorption slowly overtakes bone formation. Osteoporosis develops when there's an abnormal imbalance between bone resorption and formation — that is, resorption occurs too quickly, or formation too slowly.

The spleen, a spongy, soft organ about as big as a person’s fist, is located in the upper left part of the abdomen, just under the rib cage. The splenic artery brings blood to the spleen from the heart. Blood leaves the spleen through the splenic vein, which drains into a larger vein (the portal vein) that carries the blood to the liver. The spleen has a covering of fibrous tissue (the splenic capsule) that supports its blood vessels and lymphatic vessels. The spleen is made up of two basic types of tissue, each with different functions: White pulp Red pulp The white pulp is part of the infection-fighting (immune) system. It produces white blood cells called lymphocytes, which in turn produce antibodies (specialized proteins that protect against invasion by foreign substances). The red pulp filters the blood, removing unwanted material. The red pulp contains other white blood cells called phagocytes that ingest microorganisms, such as bacteria, fungi, and viruses. It also monitors red blood cells, destroying those that are abnormal or too old or damaged to function properly. In addition, the red pulp serves as a reservoir for different elements of the blood, especially white blood cells and platelets (cell-like particles involved in clotting). However, releasing these elements is a minor function of the red pulp.

Your egg usually lives for just 12 to 24 hours, but sperm will live inside you for anything from a few hours to seven days, with one to three days the optimum time. ... But because a small number of sperm are long-living, having sex up to six days before ovulation can also result in pregnancy.

This could be caused by an infection, food poisoning, parasites, Crohn's disease, or reduced blood flow in the colon. Hemorrhoids are another common cause of GI or rectal bleeding. A hemorrhoid is an enlarged vein in your rectum or anus. These enlarged veins can rupture and bleed, causing rectal bleeding.

Breast lumps facts Breast lumps can be caused by infections, injuries, non-cancerous growths, and cancer. Breast cancer usually causes no pain in the breast. The symptoms of breast cancer include painless breast lumps, nipple discharge, and inflammation of the skin of the breast. The chances that a particular breast lump could be cancerous depends on many factors, including past medical history, physical examination, as well as genetic and other risk factors. The only way to be certain that a lump is not cancerous is to have a tissue sampling (biopsy). There are several ways to do the biopsy. The treatment of a breast lump depends on its cause.

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.

Knee replacement, also called arthroplasty, is a surgical procedure to resurface a knee damaged by arthritis. Metal and plastic parts are used to cap the ends of the bones that form the knee joint, along with the kneecap. This surgery may be considered for someone who has severe arthritis or a severe knee injury.

Bariatric surgical procedures cause weight loss by restricting the amount of food the stomach can hold, causing malabsorption of nutrients, or by a combination of both gastric restriction and malabsorption. Bariatric procedures also often cause hormonal changes. Most weight loss surgeries today are performed using minimally invasive techniques (laparoscopic surgery). The most common bariatric surgery procedures are gastric bypass, sleeve gastrectomy, adjustable gastric band, and biliopancreatic diversion with duodenal switch. Each surgery has its own advantages and disadvantages.

See the War Inside Your Body

Treatment for kidney stones varies, depending on the type of stone and the cause. Small stones with minimal symptoms Most kidney stones won't require invasive treatment. You may be able to pass a small stone by: Drinking water. Drinking as much as 2 to 3 quarts (1.9 to 2.8 liters) a day may help flush out your urinary system. Unless your doctor tells you otherwise, drink enough fluid — mostly water — to produce clear or nearly clear urine. Pain relievers. Passing a small stone can cause some discomfort. To relieve mild pain, your doctor may recommend pain relievers such as ibuprofen (Advil, Motrin IB, others), acetaminophen (Tylenol, others) or naproxen sodium (Aleve). Medical therapy. Your doctor may give you a medication to help pass your kidney stone. This type of medication, known as an alpha blocker, relaxes the muscles in your ureter, helping you pass the kidney stone more quickly and with less pain. Large stones and those that cause symptoms Kidney stones that can't be treated with conservative measures — either because they're too large to pass on their own or because they cause bleeding, kidney damage or ongoing urinary tract infections — may require more extensive treatment. Procedures may include: Using sound waves to break up stones. For certain kidney stones — depending on size and location — your doctor may recommend a procedure called extracorporeal shock wave lithotripsy (ESWL). ESWL uses sound waves to create strong vibrations (shock waves) that break the stones into tiny pieces that can be passed in your urine. The procedure lasts about 45 to 60 minutes and can cause moderate pain, so you may be under sedation or light anesthesia to make you comfortable. ESWL can cause blood in the urine, bruising on the back or abdomen, bleeding around the kidney and other adjacent organs, and discomfort as the stone fragments pass through the urinary tract. Surgery to remove very large stones in the kidney. A procedure called percutaneous nephrolithotomy (nef-row-lih-THOT-uh-me) involves surgically removing a kidney stone using small telescopes and instruments inserted through a small incision in your back. You will receive general anesthesia during the surgery and be in the hospital for one to two days while you recover. Your doctor may recommend this surgery if ESWL was unsuccessful. Using a scope to remove stones. To remove a smaller stone in your ureter or kidney, your doctor may pass a thin lighted tube (ureteroscope) equipped with a camera through your urethra and bladder to your ureter. Once the stone is located, special tools can snare the stone or break it into pieces that will pass in your urine. Your doctor may then place a small tube (stent) in the ureter to relieve swelling and promote healing. You may need general or local anesthesia during this procedure. Parathyroid gland surgery. Some calcium phosphate stones are caused by overactive parathyroid glands, which are located on the four corners of your thyroid gland, just below your Adam's apple. When these glands produce too much parathyroid hormone (hyperparathyroidism), your calcium levels can become too high and kidney stones may form as a result. Hyperparathyroidism sometimes occurs when a small, benign tumor forms in one of your parathyroid glands or you develop another condition that leads these glands to produce more parathyroid hormone. Removing the growth from the gland stops the formation of kidney stones. Or your doctor may recommend treatment of the condition that's causing your parathyroid gland to overproduce the hormone.

Reading the 12-lead ECG

an. 4, 2017 -- Scientists say they've identified a new organ in the body -- a swath of tissue dubbed the mesentery that connects the intestine to the abdomen and holds everything in place. For years, anatomical experts have thought the organ was composed of several different segments of tissue, as opposed to being one single structure, according to Discover magazine. Since an organ must be one structure that performs a vital function, it was not deemed worthy of organ status. But recent research from doctors at the University Hospital Limerick in Ireland shows that the mesentery is actually one single band of tissue, the magazine reported Tuesday. It begins at the pancreas and wraps around the small intestine and colon. Its purpose: to hold these organs in position so they can perform their respective functions. "Without it you can't live," lead researcher Dr. J. Calvin Coffey, a colorectal surgeon at Limerick, told the magazine. "There are no reported instances of a Homo sapien living without a mesentery." "Understanding how and why our digestive system is arranged the way it is could be crucial to our understanding of diseases like Crohn's and irritable bowel syndrome," Coffey added. "There are a lot of diseases that we are stalled on, and we need to refresh our approach to these diseases," Coffey said. "Now that we've clarified its [the mesentery's] structure, we can systematically examine it. We're at a very exciting place right now." The discovery was published recently in the Lancet Gastroenterology & Hepatology journal.

Surfactant. Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants.

You're sneezing, coughing, and all stuffed up. It sounds and feels like a cold, alright. But as time goes on, you start to wonder. Is it turning into a sinus infection? They've got some things in common, but there are ways to tell them apart. The right ID lets your doctor get you the best treatment. What Is a Common Cold? It's an infection caused by a virus, a tiny living thing. You can't miss the symptoms: Nasal congestion Runny nose Post-nasal drip (drop-by-drop release of fluid from your nose into the back of the throat) Headache Fatigue You may also get a cough and a mild fever. The symptoms usually build, peak, and slowly disappear. Some medications can ease symptoms. For example, decongestants may decrease drainage and open the nasal passages. Pain relievers may help with fever and headache. Cough medicine may help, as well. Colds typically last from a few days to about a week or longer. Sometimes, a cold may cause swelling in the sinuses, hollow spaces in your skull that are connected to each other. The swelling can prevent the flow of mucus.

Chronic obstructive pulmonary disease Email this page to a friend Print Facebook Twitter Google+ Chronic obstructive pulmonary disease (COPD) is a common lung disease. Having COPD makes it hard to breathe. There are two main forms of COPD: Chronic bronchitis, which involves a long-term cough with mucus Emphysema, which involves damage to the lungs over time Most people with COPD have a combination of both conditions. Causes Smoking is the main cause of COPD. The more a person smokes, the more likely that person will develop COPD. But some people smoke for years and never get COPD. In rare cases, nonsmokers who lack a protein called alpha-1 antitrypsin can develop emphysema. Emphysema Other risk factors for COPD are: Exposure to certain gases or fumes in the workplace Exposure to heavy amounts of secondhand smoke and pollution Frequent use of a cooking fire without proper ventilation Symptoms Symptoms may include any of the following: Cough, with or without mucous Fatigue Many respiratory infections Shortness of breath (dyspnea) that gets worse with mild activity Trouble catching one's breath Wheezing Because the symptoms develop slowly, some people may not know that they have COPD.

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.

Bone tumors develop when cells in the bone divide without control, forming a mass of tissue. Most bone tumors are benign, which means they are not cancer and cannot spread. However, they may still weaken bone and lead to fractures or cause other problems. Bone cancer destroys normal bone tissue and may spread to other parts of the body (called metastasis). Benign Bone Tumors Benign tumors are more common than malignant tumors of the bones. These are a few common types of benign bone tumors: Osteochondroma is the most common benign bone tumor. It is more common in people under age 20. Giant cell tumor is a benign tumor, typically affecting the leg (malignant types of this tumor are uncommon). Osteoid osteoma is a bone tumor, often occurring in long bones, that occurs commonly in the early 20s. Osteoblastoma is a single tumor that occurs in the spine and long bones, mostly in young adults. Enchondroma usually appears in bones of the hand and feet. It often has no symptoms. It is the most common type of hand tumor.

MRI of Bone Tumor