The kidneys are a pair of organs located in the back of the abdomen. Each kidney is about 4 or 5 inches long -- about the size of a fist. The kidneys' function are to filter the blood. All the blood in our bodies passes through the kidneys several times a day. The kidneys remove wastes, control the body's fluid balance, and regulate the balance of electrolytes. As the kidneys filter blood, they create urine, which collects in the kidneys' pelvis -- funnel-shaped structures that drain down tubes called ureters to the bladder. Each kidney contains around a million units called nephrons, each of which is a microscopic filter for blood. It's possible to lose as much as 90% of kidney function without experiencing any symptoms or problems.

Sciatica is often characterized by one or more of the following symptoms: Constant pain in only one side of the buttock or leg (rarely in both legs) Pain that is worse when sitting Leg pain that is often described as burning, tingling, or searing (versus a dull ache) Weakness, numbness, or difficulty moving the leg, foot, and/or toes A sharp pain that may make it difficult to stand up or walk Pain that radiates down the leg and possibly into the foot and toes (it rarely occurs only in the foot) Sciatica Causes and Treatments Video Watch: Sciatica Causes and Treatments Video Sciatic pain can vary from infrequent and irritating to constant and incapacitating. Symptoms are usually based on the location of the pinched nerve. While symptoms can be painful and potentially debilitating, it is rare that permanent sciatic nerve damage (tissue damage) will result, and spinal cord involvement is possible but rare.

The brain is that part of the CNS contained within the cranial cavity (figure 13.1). It is the control center for many of the body's functions. The brain is much like a complex central computer but with additional functions that no computer can as yet match. Indeed, one goal in computer technology is to make computers that can function more like the human brain. The brain consists of the brainstem, the cerebellum, the diencephalon, and the cerebrum (table 13.1). The brainstem includes the medulla oblongata, pons, midbrain, and reticular formation. The structure of the brain is described in this chapter. Its functions are primarily discussed in chapter 14. Twelve pairs of cranial nerves, which are part of the PNS, arise directly from the brain. Two pairs arise from the cerebrum, nine pairs arise from the brainstem, and one pair arises from the spinal cord.

Invasive intracranial pressure monitoring. The most common surgically placed monitors for ICP measurement are intraventricular catheters (external ventricular drain [EVD] or a ventriculostomy drain) and fiberoptic ICP monitors implanted into the parenchyma of the brain.

The majority of epileptic seizures are controlled by medication, particularly anticonvulsant drugs. The type of treatment prescribed will depend on several factors, including the frequency and severity of the seizures and the person's age, overall health, and medical history. An accurate diagnosis of the type of epilepsy is also critical to choosing the best treatment. Drug Therapy Many drugs are available to treat epilepsy. Although generic drugs are safely used for most medications, anticonvulsants are one category where doctors proceed with caution. Most doctors prefer to use brand-name anticonvulsants, but realize that many insurance companies will not cover the cost. As a result, it is acceptable to start taking a generic anticonvulsant medication, but if the desired control is not achieved, the patient should be switched to the brand-name drug.

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.

It is a specialized bodily fluid that supplies essential substances and nutrients, such as sugar, oxygen, and hormones to our cells, and carries waste away from those cells, this waste is eventually flushed out of the body in urine, feces, sweat, and lungs (carbon dioxide). Blood also contains clotting agents.

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.

6 987 24 MORE How Does Anesthesia Work? Credit: itsmejust | Shutterstock If you’ve ever had surgery, unless you are super tough, you’ve gone through it with the benefit of anesthetics. But, how do these body-numbing elixirs work? Prior to the invention of anesthesia in the mid-1800s, surgeons had to hack off limbs, sew up wounds and remove mysterious growths with nothing to dull the patient's pain but opium or booze. While these drugs may have numbed the patient, they didn’t always completely block the pain, or erase the memory of it. Since then, doctors have gotten much better at putting us out with drug combinations that ease pain, relax muscles and, in some cases, put us in a deep state of hypnosis that gives us temporary amnesia. Today, there are two primary types of anesthesia drugs: those that knockout the whole body (general) and those that only numb things up locally.

You get motion sickness when one part of your balance-sensing system (your inner ear , eyes, and sensory nerves) senses that your body is moving, but the other parts don't. For example, if you are in the cabin of a moving ship, your inner ear may sense the motion of waves, but your eyes don't see any movement.

Initially, lead poisoning can be hard to detect — even people who seem healthy can have high blood levels of lead. Signs and symptoms usually don't appear until dangerous amounts have accumulated. Lead poisoning symptoms in children Signs and symptoms of lead poisoning in children include: Developmental delay Learning difficulties Irritability Loss of appetite Weight loss Sluggishness and fatigue Abdominal pain Vomiting Constipation Hearing loss Seizures Eating things, such as paint chips, that aren't food (pica) Lead poisoning symptoms in newborns Babies exposed to lead before birth might: Be born prematurely Have lower birth weight Have slowed growth Lead poisoning symptoms in adults Although children are primarily at risk, lead poisoning is also dangerous for adults. Signs and symptoms in adults might include: High blood pressure Joint and muscle pain Difficulties with memory or concentration Headache Abdominal pain Mood disorders Reduced sperm count and abnormal sperm Miscarriage, stillbirth or premature birth in pregnant women Causes Lead is a metal that occurs naturally in the earth's crust, but human activity — mining, burning fossil fuels and manufacturing — has caused it to become more widespread. Lead was also once used in paint and gasoline and is still used in batteries, solder, pipes, pottery, roofing materials and some cosmetics. Lead in paint Lead-based paints for homes, children's toys and household furniture have been banned in the United States since 1978. But lead-based paint is still on walls and woodwork in many older homes and apartments. Most lead poisoning in children results from eating chips of deteriorating lead-based paint. Water pipes and imported canned goods Lead pipes, brass plumbing fixtures and copper pipes soldered with lead can release lead particles into tap water. Lead solder in food cans, banned in the United States, is still used in some countries. Other sources of lead exposure Lead sometimes can also be found in: Soil. Lead particles from leaded gasoline or paint settle on soil and can last years. Lead-contaminated soil is still a major problem around highways and in some urban settings. Some soil close to walls of older houses contains lead. Household dust. Household dust can contain lead from lead paint chips or from contaminated soil brought in from outside. Pottery. Glazes found on some ceramics, china and porcelain can contain lead that can leach into food served or stored in the pottery. Toys. Lead is sometimes found in toys and other products produced abroad. Cosmetics. Tiro, an eye cosmetic from Nigeria, has been linked to lead poisoning. Herbal or folk remedies. Lead poisoning has been linked to greta and azarcon, traditional Hispanic medicines, as well as some from India, China and other countries. Mexican candy. Tamarind, an ingredient used in some candies made in Mexico, might contain lead. Lead bullets. Time spent at firing ranges can lead to exposure. Occupations. People are exposed to lead and can bring it home on their clothes when they work in auto repair, mining, pipe fitting, battery manufacturing, painting, construction and certain other fields

Cervical Mucus

Herpes simplex encephalitis is characterized by acute-onset (<1 week) fever, headaches, seizures, altered mental status, and focal neurologic findings such as hemiparesis or cranial nerve deficits. This patient's weakness/fatigue for >1 week, heart murmur, history of drug abuse, and absence of focal neurologic deficits make endocarditis with mycotic aneurysm more likely than herpes encephalitis

A nephron (from Greek νεφρός (nephros) meaning "kidney") is the basic structural and functional unit of the kidney. Its chief function is to regulate the concentration of water and soluble substances like sodium salts by filtering the blood, reabsorbing what is needed and excreting the rest as urine.

The male reproductive system includes the scrotum, testes, spermatic ducts, sex glands, and penis. These organs work together to produce sperm, the male gamete, and the other components of semen.

"How to Perform a Transthoracic Echocardiographic Study Volume 1: Transducer Position and Anatomy" is an instructional video, offered by ASE, and can be used for professional lectures and offers an interactive section for flexible presentations. The video includes an overview of relevant cardiac anatomy, a step by step presentation of all Transducer Positions, and the sequential transducer movements to acquire standard echo images needed to complete a Transthoracic Echocardiographic Study.

Overbite is a type or malocclusion or an overjet. A lot of people don’t realize that they have an overbite, as they believe their condition is not serious enough to obtain dental attention. This could also for the reason that other cases of overbites are so minor to be noticeable. However, others have serious overbite condition that can make the person’s top jaw look much larger or the bottom jaw significantly smaller. But one thing to remember, overbite can actually cause some dental problems. This condition can change the structure of your face and affect the way you talk. The most popular form of overbite correction is orthodontic treatment. Your dentist will fix the overbite with the help of rubber bands and dental braces to pull the upper teeth back. Tooth extraction may be suggested if overcrowding complicates the overbite so as to provide room for your front teeth. In extreme conditions, overbite surgery may be needed to place your jaw backwards or forwards. Furthermore, if severe overbite is not corrected during adulthood, the teeth may continue to shift and trigger dental issues such as gum disease.

One technique to relocate a dislocated elbow with anatomy diagrammed out.

Sound waves enter the ear canal and make the ear drum vibrate. This action moves the tiny chain of bones (ossicles – malleus, incus, stapes) in the middle ear. The last bone in this chain 'knocks' on the membrane window of the cochlea and makes the fluid in the cochlea move.

How do you know if you have an STD? There’s only one way — you have to get tested. How do they test for STDs? Here’s the good news: STD testing is usually quick and painless. Get answers to all your questions about how to get tested for STDs.