But common warts are actually an infection in the top layer of skin, caused by viruses in the human papillomavirus, or HPV, family. When the virus invades this outer layer of skin, usually through a tiny scratch, it causes rapid growth of cells on the outer layer of skin – creating the wart.

Ebola virus disease (EVD; also Ebola hemorrhagic fever, or EHF), or simply Ebola, is a viral hemorrhagic fever of humans and other primates caused by ebolaviruses. Signs and symptoms typically start between two days and three weeks after contracting the virus with a fever, sore throat, muscular pain, and headaches.

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.

Abdominal aortic aneurysms can weaken the aorta, your body’s largest blood vessel. This can develop into a potentially serious heath problem that can be fatal if the aneurysm bursts, causing massive internal bleeding. Endovascular stent grafting, or endovascular aneurysm repair (EVAR), is a newer form of treatment for abdominal aortic aneurysm that is less invasive than open surgery. Endovascular stent grafting uses an endovascular stent graft to reinforce the wall of the aorta and to help keep the damaged area from rupturing.

Asthma is a condition in which your airways narrow and swell and produce extra mucus. This can make breathing difficult and trigger coughing, wheezing and shortness of breath.

The heart is the body's engine room, responsible for pumping life-sustaining blood via a 60,000-mile-long (97,000-kilometer-long) network of vessels. The organ works ceaselessly, beating 100,000 times a day, 40 million times a year—in total clocking up three billion heartbeats over an average lifetime. It keeps the body freshly supplied with oxygen and nutrients, while clearing away harmful waste matter.

Endovascular Aneurysm Repair Endovascular aneurysm repair (or endovascular aortic repair) (EVAR) is a type of endovascular surgery used to treat pathology of the aorta, most commonly an abdominal aortic aneurysm (AAA).

If they are damaged, waste and fluids build up in your blood instead of leaving your body. Kidney damage from diabetes is called diabetic nephropathy. It begins long before you have symptoms. An early sign of it is small amounts of protein in your urine.

Spermatogenesis is the process in which spermatozoa are produced from spermatogonial stem cells by way of mitosis and meiosis. The initial cells in this pathway are called spermatogonia, which yield primary spermatocytes by mitosis.

Appendicitis is an inflammation of the appendix, a 3 1/2-inch-long tube of tissue that extends from the large intestine. No one is absolutely certain what the function of the appendix is. One thing we do know: We can live without it, without apparent consequences.

Root canals are common procedures and can help save your tooth from extraction. Dentists at Aspen Dental practices have been safely and expertly performing root canal procedures for over two decades.

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HIV gradually destroys the immune system by attacking and killing a type of white blood cell called a CD4 cell. CD4 cells play a major role in protecting the body from infection. HIV uses the machinery of the CD4 cells to multiply (make copies of itself) and spread throughout the body. This process, which is carried out in seven steps or stages, is called the HIV life cycle. HIV medicines protect the immune system by blocking HIV at different stages of the HIV life cycle. Antiretroviral therapy or ART is the use of HIV medicines to treat HIV infection. People on ART take a combination of HIV medicines from at least two different HIV drug classes every day. Because each class of drugs is designed to target a specific step in the HIV life cycle, ART is very effective at preventing HIV from multiplying. ART also reduces the risk of HIV drug resistance. ART can’t cure HIV, but HIV medicines help people with HIV live longer, healthier lives. ART also reduces the risk of HIV transmission (the spread of HIV to others).

Shoulder dystocia is a rare emergency that can happen during the end of the second stage of labour. It's all to do with how your baby moves down through your vagina and out into the world. Shoulder dystocia happens when your baby's head has been born, but one of her shoulders becomes stuck.

During surgery to repair the hernia, the bulging tissue is pushed back in. Your abdominal wall is strengthened and supported with sutures (stitches), and sometimes mesh. This repair can be done with open or laparoscopic surgery. You and your surgeon can discuss which type of surgery is right for you.

The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins.

A heart attack is a frightening, confusing and stressful experience. Life after a heart attack isn’t easy, but we’re with you all the way on your journey toward recovery. Here you will find information about heart attack warning signs, risk factors, diagnosis, treatment, and life as a survivor or caregiver. You will also find heart attack tools and resources to help you get and stay healthy.

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If it is not removed, tooth decay will begin. The acids in plaque damage the enamel covering your teeth. It also creates holes in the tooth called cavities. Cavities usually do not hurt, unless they grow very large and affect nerves or cause a tooth fracture.

The cornea occupies the front center part of the outer wall of the eye. It is made of collagen fibers in a very special arrangement so that the cornea is clear. One looks through the cornea to see the iris and pupil. The cornea bends light coming into the eye so that it is focused on the retina.