Pancreatic Cancer

The pancreas is a six-inch-long gland in the abdomen* that is surrounded by the stomach, intestine, and other digestive organs. It is shaped like a long, flattened pear, wide at one end and narrow at the other.

Pancreatitis

*inflammation (in-fla-MAY-shun) is the body's response to infection or irritation, usually marked by heat swelling, redness, and pain.

Paralysis

As she was warming up for her routine at the July 1998 Goodwill Games, 17-year-old Chinese gymnast Sang Lan prepared to jump over the vaulting horse, a move she had performed thousands of times. But Sang flung herself too forcefully into the vault and landed on her head instead of her feet.

Parasitic Diseases

Most of the world's 6 billion people are infected with parasites, which are primitive animals that live in or on the bodies of humans, animals, or insects. Often the parasites do little damage, and people may be unaware they are infected.

Parkinson's Disease

Actor Michael J. Fox first noticed the twitch in his left little finger in 1991 while filming the movie Doc Hollywood.

Pelvic Inflammatory Disease (PID)

Two years after Carrie and Reg got married, they decided to start a family. Carrie began looking at the ads for strollers and baby clothes.

Peptic Ulcer

Early in the twentieth century, peptic ulcers were thought to be caused by emotional stress and spicy foods. As a result, people were treated with bed rest and a bland diet, but they often failed to get better.

Peritonitis

A number of conditions can cause peritonitis. Usually, peritonitis occurs when an infection develops in the peritoneum from a perforation (per-fo-RAY-shun), or hole, in the stomach, intestines, appendix, or one of the other organs covered by the lining.

Phenylketonuria (PKU)

In 1934, a mother with two children with mental retardation went to a Norwegian medical doctor, Asbjørn Følling. Dr.

Phlebitis

Terry decided to visit her doctor because her lower left leg hurt. It also appeared swollen and red and even felt a bit warm to the touch.

Phobias

Whenever Bethani, who recently turned 15, enters a building above two stories, she checks to see if the building has stairs. She is intensely afraid of riding an elevator.

Pinworm (Enterobiasis)

Pinworm, or Enterobius vermicularis (en-ter-O-be-us ver-mik-u-LAY-ris), is a common and highly contagious* intestinal parasite. An estimated The human pinworm, Enterobius vermicularis, magnified approximately 35x.

Plague

In about 1300, a massive epidemic of a deadly disease known as plague began. The epidemic, sometimes called the Black Death, started in Asia, then spread westward from the Middle East to North Africa and Europe.

Pleurisy

In pleurisy, the membrane covering the lungs and lining the chest cavity becomes inflamed, and excess fluids may build up in the space. When people who have pleurisy breathe in or cough, the inflammation causes pain, which is a result of friction from the inflamed pleura.

Pneumoconiosis

Only microscopic-size dust particles, about 1/5,000 of an inch across or smaller, are able to reach the tiniest air sacs (the alveoli) in the lungs. There they cannot be removed, and accumulate to cause a scarring and thickening of the lungs called fibrosis (fy-BRO-sis).

Pneumonia

Each day a person inhales large amounts of air, often laden with germs, dust, and other partides. The air is drawn deep into the lungs, two spongy air sacs in the chest where oxygen from the air is transferred to the blood.

Poliomyelitis

Remarkable photographs from the mid twentieth century show people—sometimes a large roomful—enclosed in metal tanks being attended to by nurses. The tanks were called iron lungs.

Polyps

Three of the most common types include colorectal, cervical, and nasal polyps.

Porphyria

*genes are chemicals in the body that help determine a person's characteristics, such as hair or eye color. They are inherited from a person's parents and are contained in the chromosomes found in the cells of the body.

Post-Traumatic Stress Disorder

Sara felt herself trying to scream, but no sound came from her throat. Hands seemed to be gripping her.

Pregnancy, Complications of

Pregnancy is the interval of time beginning when an egg and sperm unite and ending when a baby is born. A full-term pregnancy lasts 9 months (38 to 40 weeks).

Prematurity

In the third trimester* of pregnancy (months 7, 8, and 9), the fetus* adds ounces of body weight and is better prepared for living outside the mother's body. Many premature babies are not ready to live on their own.