The essential components of the human cardiovascular system are the heart, blood and blood vessels. It includes the pulmonary circulation, a "loop" through the lungs where blood is oxygenated; and the systemic circulation, a "loop" through the rest of the body to provide oxygenated blood.

Blood type (or blood group) is determined, in part, by the ABO blood group antigens present on red blood cells. A blood type (also called a blood group) is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs).

Cells may have slender extensions of the cell membrane to form cilia or the smaller extensions called microvilli. The microscopic microvilli effectively increase the surface area of the cell and are useful for absorption and secretion functions. A dramatic example is the human small intestine. The tissue has small fingerlike extensions called villi which are collections of cells, and those cells have many microvilli to even further increase the available surface area for the digestion process. According to Audesirk & Audesirk, this can give an effective surface area of about 250 square meters for absorption.

Schwannomas are usually located in the angle between the cerebellum and the pons, in the back of the skull (the posterior fossa). Description Schwannomas are usually very slow-growing. Symptoms Common symptoms of Schwannoma are one-sided hearing loss and buzzing or ringing in the ear. Dizziness may also occur, although it is less common. If the tumor affects the facial nerve (the 7th cranial nerve, which is located next to the 8th cranial nerve), facial paralysis may occur. Other symptoms include difficulty in swallowing, impaired eye movement, taste disturbances, and unsteadiness. Incidence Schwannomas account for about 8% of all primary brain tumors. They typically occur in middle-aged adults, and females are twice as likely as males to have this tumor. Cause Like many tumor types, the exact cause of Schwannoma is not known. However, it is believed to occur when there is a defect in a gene that normally prevents tumors from forming. Treatment Total removal using microsurgical techniques is often possible. Stereotactic radiosurgery may be used as an alternative to surgery in some patients.

When taking oral corticosteroids longer term, you may experience: Clouding of the lens in one or both eyes (cataracts) High blood sugar, which can trigger or worsen diabetes. Increased risk of infections. Thinning bones (osteoporosis) and fractures. Suppressed adrenal gland hormone production

Gallstone ileus is an important, though infrequent, cause of mechanical bowel obstruction, affecting older adult patients who often have other significant medical conditions. It is caused by impaction of a gallstone in the ileum after being passed through a biliary-enteric fistula. The diagnosis is often delayed since symptoms may be intermittent and investigations fail to identify the cause of the obstruction. The mainstay of treatment is removal of the obstructing stone after resuscitating the patient. Gallstone ileus continues to be associated with relatively high rates of morbidity and mortality.

In developing countries, domestic animals (eg, dogs) are common sources of infection. In the United States, bats and wild animals (eg, raccoons) are the most common reservoirs of infection. The acquisition of rabies from bats can occur from an unrecognized bite or a scratch, and possibly by inhalation of aerosolized viral particles. Bats are found in all states except Hawaii, and spelunking (cave exploration) is a risk factor for rabies acquisition from bats.

Indwelling urinary catheters are commonly used in hospitals and can lead to preventable catheter-associated UTI. How can rates of catheter-associated UTI be reduced in hospitals? New research findings are summarized in a new NEJM Quick Take. Learn more at http://nej.md/1WoeHdF SHOW MORE

This video has been shortened for quicker review of the procedure. This patient's knee was dislocated during a motor vehicle accident. In this video the reduction of the dislocated knee is demonstrated.

This patient's age, speech delay, bilateral lower-extremity weakness, apparent increase in calf diameter, and history of a wheelchair-bound uncle are typical of Duchenne muscular dystrophy (DMD). DMD is the most common muscular dystrophy of childhood that affects boys who have inherited a defective dystrophin gene on X-chromosome p21. Weakness begins in the proximal lower-extremity muscles and manifests as difficulty walking, running, jumping, and climbing stairs. Boys may push their arms on their thighs (Gower sign) to transition from sitting to standing.

ATTENTION! 5 Warning Signs Of BREAST CANCER That Many Women Ignore!

-Traumatic amputation of a body part requires rapid transport of the appendage, which should be wrapped in a saline-moistened gauze, placed in a plastic bag, and transported in a container filled with ice mixed with either saline or sterile water to best preserve the body part and attempt replantation.

Craziest Surgeries You'll Never Believe Occurred!

Dumping syndrome is a condition that can develop after surgery to remove all or part of your stomach or after surgery to bypass your stomach to help you lose weight. Also called rapid gastric emptying, dumping syndrome occurs when food, especially sugar, moves from your stomach into your small bowel too quickly. Most people with dumping syndrome develop signs and symptoms, such as abdominal cramps and diarrhea, 10 to 30 minutes after eating. Other people have symptoms one to three hours after eating, and still others have both early and late symptoms. Generally, you can help prevent dumping syndrome by changing your diet after surgery. Changes might include eating smaller meals and limiting high-sugar foods. In more-serious cases o

One thing we do know: We can live without it, without apparent consequences. Appendicitis is a medical emergency that requires prompt surgery to remove the appendix. Left untreated, an inflamed appendix will eventually burst, or perforate, spilling infectious materials into the abdominal cavity.

In patients with advanced congestive heart failure due to cardiomyopathy or ischemia, right ventricle shortening is the only significant independent associate of survival by multivariate analysis (as opposed to other parameters including left ventricular ejection fraction, cardiac index, and pulmonary resistance).

Here is how surgeons perform knock knee correction surgery. Titanium plate is used to stabilize the affected area. The femur is cut nearly through to help with the stability. Spreaders angle the cut align the leg. The plate is secured with several screws. Synthetic bone graft material is packed in the joint. The patient will be in crutches for 4 to 6 weeks.

Behcet's (beh-CHETS) disease, also called Behcet's syndrome, is a rare disorder that causes blood vessel inflammation throughout your body. The disease can lead to numerous signs and symptoms that may seem unrelated at first. They may include mouth sores, eye inflammation, skin rashes and lesions, and genital sores. The effects of Behcet's disease vary from person to person and may clear up on their own. Treatment involves medications to reduce the signs and symptoms of Behcet's disease and to prevent serious complications, such as blindness.

Cardiac tamponade is a medical emergency that requires urgent drainage of the pericardial fluid. Preferably, patients should be monitored in an intensive care unit. All patients should receive the following: Oxygen Volume expansion with blood, plasma, dextran, or isotonic sodium chloride solution, as necessary, to maintain adequate intravascular volume - Sagristà-Sauleda et al noted significant increase in cardiac output after volume expansion [24] (see the Cardiac Output calculator) Bed rest with leg elevation - This may help increase venous return Positive-pressure mechanical ventilation should be avoided because it may decrease venous return and aggravate signs and symptoms of tamponade. Inpatient care After pericardiocentesis, leave the intrapericardial catheter in place after securing it to the skin using sterile procedure and attaching it to a closed drainage system via a 3-way stopcock. Periodically check for reaccumulation of fluid, and drain as needed. The catheter can be left in place for 1-2 days and can be used for pericardiocentesis. Serial fluid cell counts can be useful for helping to discover an impending bacterial catheter infection, which could be catastrophic. If the white blood cell (WBC) count rises significantly, the pericardial catheter must be removed immediately. A Swan-Ganz catheter can be left in place for continuous monitoring of hemodynamics and to assess the effect of reaccumulation of pericardial fluid. A repeat echocardiogram and a repeat chest radiograph should be performed within 24 hours.

This medication is used in emergencies to treat very serious allergic reactions to insect stings/bites, foods, drugs, or other substances. Epinephrine acts quickly to improve breathing, stimulate the heart, raise a dropping blood pressure, reverse hives, and reduce swelling of the face, lips, and throat.