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Despite its diminutive name, the small intestine is actually the longest part of the digestive tract, stretching some 22 feet in length. The large intestine, however, is just 5 feet long. j3b2bm
When full, the stomach holds between a quart and a quart and a half of food and liquids. And it takes about four hours for the stomach to fully digest a meal and pass it along to the small intestine. Food passes through the small intestine in just two hours, zipping along at 0.002 mph. Inside the large intestine, it takes about 14 hours, traveling at a more leisurely rate of 0.00007 mph.
The inside of the small intestine, which absorbs the digested proteins, sugars and fats from food, is covered with a fur-like layer of tiny projections called villi and microvilli. This food-absorbing "fur" boosts the surface area by 600 times, compared to what a smooth interior surface would provide. If the interior of the small intestine were smooth, it would have to be 2 1/4 miles long to provide the same food absorbing power as its present 22 feet.
Each day, about three gallons of food, liquids and digestive juices gurgles its way through the digestive tract. Only about half a cup emerges as feces.

Nasul gura limba

The nose traps and filters up to 70 percent of the 20 billion dust particles that we inhale each day. It also changes the temperature of the incoming air to between 77 and 95 degrees F and regulates humidity to between 35 percent and 80 percent.
Each year, people living in the United States catch almost 1 billion colds. That's as many as six colds per person per year. The reason: There are 110 different rhinoviruses, the most common cold-causer, plus about 90 other kinds of cold-causing viruses.
The fastest sneeze ever recorded was clocked at just over 100 mph.
Your nose contains 20 types of odor-detecting cells. With these, you can distinguish up to 10,000 different smells.
The tongue has 10,000 taste buds, but they can detect only four basic taste sensations - sweet, sour, bitter and salty.
The mouth produces about a quart of saliva each day.




Sangele si inima

There are five quarts of blood in the adult human body, and the entire blood supply makes a complete circuit of the heart, lungs, blood vessels, and back to the heart every 60 seconds.
There are four major blood groups, O, A, B and AB. Nearly half the population is Type O, and they can donate blood to people with all other blood groups but can only receive group O blood. The rarest blood type, AB, is present in about 4 percent of the population. These people can receive all types of blood.
There are about 50 to 75 trillion cells in the body, about half of these are red blood cells. An individual red blood cell contains about 250 million molecules of the iron-containing protein called hemoglobin, which is capable of picking up four molecules of oxygen. As a result, a single red blood cell can deliver up to 1 billion molecules of oxygen.
Laid end-to-end, the arteries, capillaries and veins would stretch for about 60,000 miles in the average child and would be about 100,000 miles in an adult - enough to wrap around the world nearly four times.

Pielea

The average man has about 20 square feet of skin that weighs about 10 pounds.
Each square inch of skin contains as many as 650 sweat glands, 20 blood vessels, more than 1,000 nerve endings, and has up to 20 million bacteria on its surface.
Skin is thickest - about 1/5 inch - on the upper back. It is thinnest on the eyelids, which are only 1/50th inch thick.
Fingernails grow about 1 millimeter (.04 inch) every 10 to 15 days. Nails grow faster on your favored hand and on your longer fingers.
Millions of dead skin cells are replaced each day with new ones. Dandruff occurs when dead skin cells on your scalp combine with dirt and oils.

Plamanii

At about 11 inches long and nearly 6 inches wide, the lungs are your largest organ but together only weigh about two pounds. They contain about 1 1/2 gallons of air.
The inside of your lungs is covered with 600 million tissue-thin sacks called alveoli. Oxygen passes easily through the 1/6,000th-of-an-inch-thick walls of the alveoli into the capillaries that surround them. Stretched out flat, the alveoli would cover a tennis court.
Each day, the average adult inhales about 4,250 gallons of air, containing about 40 billion trillion molecules of oxygen. Along with it comes about 20 billion particles of dirt and other foreign matter.
When you cough, the air rushing out of your lungs hits speeds of up to 600 mph - close to the speed of sound.

Muschii

Most of your body is muscle. There are 650 muscles, and they make up between 40 percent and 50 percent of the total body weight in men and 30 percent to 40 percent of women's weight.
The biggest muscle in the body is the gluteus maximus - the butt. Each of the two cheeky muscles tips the scales at about two pounds (not including the overlying fat layer). The tiniest muscle, the stapedius of the middle ear, is just one-fifth of an inch long.
Most cells in the body are microscopic in size, but muscle cells, also called muscle fibers, can be up to 1 foot long and visible to the naked eye

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The adult brain contains 100 billion neurons - more than the number of stars in the Milky Way galaxy. Each of the brain's neurons connects to as many as 100,000 other neurons.
At three pounds, the brain makes up only 2 percent of total body weight but consumes 25 percent of the energy used by the entire body.
Nerve impulses are not electrical; instead, they are passed along by rapid chemical changes in nerve fibers. While the light from your computer screen streams at you at 186,000 miles per second, the nerve impulses carrying images from your eyes to your brain, for instance, saunter along at a mere 250 mph.

Oasele

When you're born, you have 300 bones. But an adult has only 206 bones. What happens? Many bones, such as those that make up the skull and spine, fuse together as we grow.
Most people have 12 pairs of ribs, but about 5 percent of the population has an extra pair.
The tiniest bone in the body is the stirrup bone in the ear, which is just one-eighth of an inch long. The longest bone is the femur, which varies in length from person to person but is about one-fourth of a person's overall height.
Hand over foot: There are 54 bones in all in your wrists, hands and fingers but only 52 in both feet, ankles and toes.



Study: Chest Compressions Alone Can Save Lives After Cardiac Arrest
May 24, 2000
The Associated Press
At a time when many people are afraid to give mouth-to-mouth to a stranger in cardiac arrest, a surprising new study found that performing just chest compressions until the ambulance arrives may save more lives than doing both.
The finding could soon lead to major changes in the CPR instructions dispatchers give to ordinary people who call 911.
"This will probably catch on quickly," said Dr. Russell Harris, past president of the New Jersey chapter of the American College of Emergency Physicians and chief of emergency medicine at Our Lady of Lourdes Medical Center in Camden, New Jersey.
"It's an excellent recommendation that may actually increase the number of people who receive bystander CPR" by ending worries of catching hepatitis, AIDS or other diseases from mouth-to-mouth contact, he said.
In a study in Thursday's issue of the New England Journal of Medicine, University of Washington researchers found that 40 percent of Seattle-area cardiac arrest patients who were given only chest compressions by bystanders survived to reach a hospital, compared with 34 percent of those who also received mouth-to-mouth resuscitation.
Nearly 15 percent of the 241 patients receiving chest compressions alone eventually made it home from the hospital, compared with only about 10 percent of the 279 who received both components of CPR, or cardiopulmonary resuscitation.
That means that patients getting both seemed only three-quarters as likely to make it out of the hospital alive.
Al Hallstrom, a professor of biostatistics who led the research, said there were not enough patients in the study to say for certain whether those getting only compressions really do fare better, but "we are reasonably sure it's better."
Hallstrom said one explanation is that it takes longer for a dispatcher to explain to someone with no medical training how to perform both components of CPR - 2.4 minutes vs. 1 minute.
Harris and other experts also said it is too complicated for many untrained people during an emergency to correctly alternate chest compressions with mouth-to-mouth resuscitation, which involves extending the person's neck, squeezing the nostrils shut and blowing forcefully into the mouth.
The study focused on cases of cardiac arrest caused by ventricular fibrillation, a quickly fatal condition in which the heart's main pumping chambers quiver instead of delivering blood to the rest of the body.
Hallstrom said giving chest compressions alone works because when the heart goes into ventricular fibrillation, most of the blood still contains oxygen. So compressions that keep the blood circulating can supply the brain, heart and other organs with enough oxygen for several minutes.
Robert Martin, executive director of the National Academy of Emergency Medical Dispatch, which writes CPR instructions for thousands of dispatchers nationwide, said that in August, the group will debate whether untrained bystanders should be told to give just chest compressions.
"It's likely going to be accepted at some time in the near future," Martin said.
The study was done from 1992 to 1998 in the dispatch center in Washington's King County.
When someone witnessing an apparent cardiac arrest called emergency, a dispatcher would send help and ask if the caller knew CPR. If not, the dispatcher would randomly instruct the caller either to give just chest compressions, or to give mouth-to-mouth too.
The researchers excluded cases where respiratory arrest, drug overdose, stroke or something else was the primary problem.
Jerry Potts of the American Heart Association said the compression-only strategy "may be a preferred way for instructing someone who has never had CPR training."
The association is drawing up new guidelines for release in August. In the meantime, "overall, we would still recommend that a combination of chest compression and ventilation be used whenever it's by a person who has had training in CPR," Potts said.
Meanwhile, Harris said medical personnel may end up scrapping the term CPR because the "pulmonary" part - the lungs - would no longer be involved.




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