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Cystinuria is a condition characterized by the buildup of the amino acid cystine, a building block of most proteins, in the kidneys and bladder. As the kidneys filter blood to create urine, cystine is normally absorbed back into the bloodstream. People with cystinuria cannot properly reabsorb cystine into their bloodstream, so the amino acid accumulates in their urine. As urine becomes more concentrated in the kidneys, the excess cystine forms crystals. Larger crystals become stones that may lodge in the kidneys or in the bladder. Sometimes cystine crystals combine with calcium molecules in the kidneys to form large stones. These crystals and stones can create blockages in the urinary tract and reduce the ability of the kidneys to eliminate waste through urine. The stones also provide sites where bacteria may cause infections.
The virus was first discovered in 1964 when Sir Michael Anthony Epstein and Ms. Yvonne Barr found it in a Burkitt lymphoma cell line. In 1968, the virus was linked to the disease infectious mononucleosis. Infection with Epstein-Barr virus (EBV) is common and usually occurs in childhood or early adulthood. EBV is the cause of infectious mononucleosis (also termed "mono"), an illness associated with fever, sore throat, swollen lymph nodes in the neck, and sometimes an enlarged spleen. It is also known as human herpes virus 4. Although EBV can cause mononucleosis, not everyone infected with the virus will get mononucleosis. Less commonly, EBV can cause more serious disease. Symptoms caused by EBV are usually mild and self-limited, but the virus persists in the body for life. It can be reactivated quietly without causing symptoms and may contaminate saliva. Thus, otherwise healthy people can spread the virus to uninfected people through kissing or sharing
Diabetic ketoacidosis is a serious complication of diabetes that occurs when your body produces high levels of blood acids called ketones. The condition develops when your body can't produce enough insulin. Insulin normally plays a key role in helping sugar (glucose) — a major source of energy for your muscles and other tissues — enter your cells. Without enough insulin, your body begins to break down fat as fuel. This process produces a buildup of acids in the bloodstream called ketones, eventually leading to diabetic ketoacidosis if untreated. If you have diabetes or you're at risk of diabetes, learn the warning signs of diabetic ketoacidosis — and know when to seek emergency care.
An intra-aortic balloon pump (IABP) is a mechanical device that helps the heart pump blood. This device is inserted into the aorta, the body's largest artery. It is a long, thin tube called a catheter with a balloon on the end of it. If you are hospitalized, your doctor may insert an IABP. Your doctor will numb an area of your leg and thread the IABP through the femoral artery in your leg into your aorta. He or she then positions the IABP at the center of your aorta, below your heart. The doctor will use an X-ray machine during this procedure to help accurately position the IABP. Why is it used? An IABP might be used to stabilize a person who is in the hospital for acute mitral valve regurgitation or severe heart failure. An IABP is only used for a short period of time (hours to days). A long-term treatment will likely be needed, such as valve surgery or the insertion of a left ventricular assist device (LVAD).
Gastroesophageal reflux disease (GERD) is a chronic digestive disease. GERD occurs when stomach acid or, occasionally, stomach content, flows back into your food pipe (esophagus). The backwash (reflux) irritates the lining of your esophagus and causes GERD. Both acid reflux and heartburn are common digestive conditions that many people experience from time to time. When these signs and symptoms occur at least twice each week or interfere with your daily life, or when your doctor can see damage to your esophagus, you may be diagnosed with GERD. Most people can manage the discomfort of GERD with lifestyle changes and over-the-counter medications. But some people with GERD may need stronger medications, or even surgery, to reduce symptoms.
Benign prostatic hyperplasia (BPH), also known as benign prostatic hypertrophy, is a histologic diagnosis characterized by proliferation of the cellular elements of the prostate. Cellular accumulation and gland enlargement may result from epithelial and stromal proliferation, impaired preprogrammed cell death (apoptosis), or both. BPH involves the stromal and epithelial elements of the prostate arising in the periurethral and transition zones of the gland (see Pathophysiology). The hyperplasia presumably results in enlargement of the prostate that may restrict the flow of urine from the bladder. BPH is considered a normal part of the aging process in men and is hormonally dependent on testosterone and dihydrotestosterone (DHT) production. An estimated 50% of men demonstrate histopathologic BPH by age 60 years. This number increases to 90% by age 85 years. The voiding dysfunction that results from prostate gland enlargement and bladder outlet obstruction (BOO) is termed lower urinary tract symptoms (LUTS). It has also been commonly referred to as prostatism, although this term has decreased in popularity. These entities overlap; not all men with BPH have LUTS, and likewise, not all men with LUTS have BPH. Approximately half of men diagnosed with histopathologic BPH demonstrate moderate-to-severe LUTS. Clinical manifestations of LUTS include urinary frequency, urgency, nocturia (awakening at night to urinate), decreased or intermittent force of stream, or a sensation of incomplete emptying. Complications occur less commonly but may include acute urinary retention (AUR), impaired bladder emptying, the need for corrective surgery, renal failure, recurrent urinary tract infections, bladder stones, or gross hematuria. (See Presentation.) Prostate volume may increase over time in men with BPH. In addition, peak urinary flow, voided volume, and symptoms may worsen over time in men with untreated BPH (see Workup). The risk of AUR and the need for corrective surgery increases with age.
Most women have between 11 and 13 menstrual periods each year. You may be different: You may have more or fewer. Missed or irregular periods must be looked at in terms of what is normal for you. Menstrual periods are often irregular during the first few years after menstruation starts. It may take several years for the hormones that control menstruation to reach a balance. Menstrual periods also may be very irregular at the other end of the menstrual years. Many women realize that they are approaching perimenopause and menopause when their otherwise regular periods become irregular. Menopause occurs when it has been 12 months since you had a menstrual period. Pregnancy is the most common cause of a missed period. If you might be pregnant, treat yourself as if you are pregnant until you know for sure. Use a home pregnancy test as the first step to finding out whether you are pregnant.
Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is therapy using ionizing radiation, generally as part of cancer treatment to control or kill malignant cells. Radiation therapy may be curative in a number of types of cancer if they are localized to one area of the body.
Can the flu be treated? Yes. There are prescription medications called “antiviral drugs” that can be used to treat flu illness. What are antiviral drugs? Antiviral drugs are prescription medicines (pills, liquid, an inhaled powder, or an intravenous solution) that fight against the flu in your body. Antiviral drugs are not sold over-the-counter. You can only get them if you have a prescription from your doctor or health care provider. Antiviral drugs are different from antibiotics, which fight against bacterial infections. What should I do if I think I have the flu? If you get the flu, antiviral drugs are a treatment option. Check with your doctor promptly if you are at high risk of serious flu complications (see box below for the full list of high risk factors). Flu symptoms can include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue. Your doctor may prescribe antiviral drugs to treat your flu illness. Should I still get a flu vaccine? Yes. Antiviral drugs are not a substitute for getting a flu vaccine. While flu vaccine can vary in how well it works, a flu vaccine is the first and best way to prevent seasonal influenza. Antiviral drugs are a second line of defense to treat the flu (including seasonal flu and variant flu viruses) if you get sick.
Cushing syndrome occurs when your body is exposed to high levels of the hormone cortisol for a long time. Cushing syndrome, sometimes called hypercortisolism, may be caused by the use of oral corticosteroid medication. The condition can also occur when your body makes too much cortisol on its own. Too much cortisol can produce some of the hallmark signs of Cushing syndrome — a fatty hump between your shoulders, a rounded face, and pink or purple stretch marks on your skin. Cushing syndrome can also result in high blood pressure, bone loss and, on occasion, type 2 diabetes. Treatments for Cushing syndrome can return your body's cortisol production to normal and noticeably improve your symptoms. The earlier treatment begins, the better your chances for recovery.
Near the end of diastole, the ventricles nearly fill with blood, and then the atria contract, adding even more volume to the ventricles. The volume of blood in the ventricles at the end of diastole is referred to as the end-diastolic volume. The other phase of the cardiac cycle is called systole.
Cluster headaches, occur in cyclical patterns or clusters, are one of the most painful types of headache. A cluster headache commonly awakens you in the middle of the night with intense pain in or around one eye on one side of your head. Bouts of frequent attacks, known as cluster periods, can last from weeks to months, usually followed by remission periods when the headaches stop. During remission, no headaches occur for months and sometimes even years. Fortunately, cluster headache is rare and not life-threatening. Treatments can make cluster headache attacks shorter and less severe. In addition, medications can reduce the number of cluster headaches.
Take regular breaks. If you are in a prolonged standing position or a prolonged sitting position, take regular breaks and move your arms or legs. Take a short walk, do some leg or arm exercises, on the spot walking/running, or take a walk outside the workplace. Get your circulation moving to your extremities.
High blood pressure and high cholesterol are the most common causes of these spasms. Approximately 2 percent of people with angina, or chest pain and pressure, experience coronary artery spasms. Coronary artery spasms can also occur in people who have atherosclerosis.