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Acute sinusitis can be triggered by a cold or allergies and may resolve on its own. Chronic sinusitis lasts up to eight weeks and may be caused by an infection or growths. Symptoms include headache, facial pain, runny nose, and nasal congestion. Acute sinusitis usually doesn't require any treatment beyond symptomatic relief with pain medications, nasal decongestants, and nasal saline rinses. Chronic sinusitis may require antibiotics.
This is an Abdominal Liposuction surgery performed by Dr. Art Foley. Liposuction is a procedure that can help sculpt the body by removing unwanted fat from specific areas including the abdomen, hips, buttocks, thighs, knees, upper arms and neck. Although no type of liposuction is a substitute for dieting and exercise, liposuction can remove stubborn areas of fat that don't respond to traditional weight loss methods.
The eyes A close up of a young person's eyes. The eyes are responsible for four-fifths of all the information our brain receives. Here you can find out a bit more about how they work, common problems that affect vision and the work Sightsavers does to treat and prevent avoidable blindness. You can also find out more about the people whose lives have been changed thanks to donations from people like you. How do eyes work? (click image to see enlarged version or click here for text alternative) Graphic of an eye with information about its different parts The images we see are made up of light reflected from the objects we look at. This light enters the eye through the cornea. Because this part of the eye is curved, it bends the light, creating an upside down image on the retina (this is eventually put the right way up by the brain). The retina is a complex part of the eye, but only the very back of it is light sensitive. This part of the retina has roughly the area of a 10p coin, and is packed with photosensitive cells called rods and cones. Cones are the cells responsible for daylight vision. There are three kinds – each responding to a different wavelength of light: red, green and blue. The cones allow us to see images in colour and detail. Rods are responsible for night vision. They are sensitive to light but not to colour. In darkness, the cones do not function at all. How do we see an image? The lens focuses the image. It can do this because it is adjustable – using muscles to change shape and help us focus on objects at different distances. The automatic focusing of the lens is a reflex response and is not controlled by the brain. Once the image is clearly focused on the sensitive part of the retina, energy in the light that makes up that image creates an electrical signal. Nerve impulses can then carry information about that image to the brain through the optic nerve.
Researchers believe that the infectious agent that causes mad cow disease is an abnormal version of a protein normally found on cell surfaces, called a prion. For reasons still unknown, this protein becomes altered and destroys nervous system tissue -- the brain and spinal cord.
It then spreads down the bundle of his and then purkinje fibres to cause ventricular contraction. So when viewing the heart from the front, the direction of depolarisation is 11 o'clock to 5 o'clock. The general direction of depolarisation is known as the cardiac axis.