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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.
A new report analyzing FDA-approved monoclonal antibodies (mAbs) produced by a select group of leading biotechnology companies shows that clinical development times – specifically the duration of Phase II and Phase III trials – are lengthening, while FDA review times have remained constant. The average time from investigational new drug (IND) filing to market was 6.7 years for 11 mABs approved between 1994 and 2003 but shot up to 8.3 years for 12 mAbs approved between 2004 and March 9, 2011, according to Deloitte Recap LLC’s analysis, Therapeutic Monoclonal Antibodies – Insights, Strategies and Data.
Endoscopic retrograde cholangiopancreatography, or ERCP, is a specialized technique used to study the bile ducts, pancreatic duct and gallbladder. Ducts are drainage routes; the drainage channels from the liver are called bile or biliary ducts. The pancreatic duct is the drainage channel from the pancreas.
A narrowing of the major artery (the aorta) that carries blood to the body. This narrowing affects blood flow where the arteries branch out to carry blood along separate vessels to the upper and lower parts of the body. CoA can cause high blood pressure or heart damage.
Nephrotic syndrome is a kidney disorder that causes your body to excrete too much protein in your urine. Nephrotic syndrome is usually caused by damage to the clusters of small blood vessels in your kidneys that filter waste and excess water from your blood. Nephrotic syndrome causes swelling (edema), particularly in your feet and ankles, and increases the risk of other health problems. Treatment for nephrotic syndrome includes treating the underlying condition that's causing it and taking medications. Nephrotic syndrome can increase your risk of infections and blood clots. Your doctor may recommend medications and dietary changes to prevent these and other complications of nephrotic syndrome.
Post-streptococcal GN is a form of glomerulonephritis. It is caused by an infection with a type of streptococcus bacteria. The infection does not occur in the kidneys, but in a different part of the body, such as the skin or throat. The strep bacterial infection causes the tiny blood vessels in the filtering units of the kidneys (glomeruli) to become inflamed. This makes the kidneys less able to filter the urine. Post-streptococcal GN is uncommon today because infections that can lead to the disorder are commonly treated with antibiotics. The disorder may develop 1 to 2 weeks after an untreated throat infection, or 3 to 4 weeks after a skin infection. It may occur in people of any age, but it most often occurs in children ages 6 through 10. Although skin and throat infections are common in children, post-streptococcal GN is a rare complication of these infections. Risk factors include: Strep throat Streptococcal skin infections (such as impetigo)
Sex easily falls to the wayside during pregnancy. Research shows that good sex has a significant impact upon not just the relationship, but also a woman’s ability to have an easeful and even joyful birth. Unfortunately, sex during pregnancy can be quite complicated for a variety of physical and emotional reasons. This week’s video will outline how to overcome these hurdles and make sure you continue to enjoy the wonders of sex as you embark on the first steps of parenthood.
A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery. A cataract can occur in either or both eyes. It cannot spread from one eye to the other.
As a result, the amount of glucose in the blood increases while the cells are starved of energy. Over time, high blood glucose levels damage nerves and blood vessels, leading to complications such as heart disease and stroke, the leading causes of death among people with diabetes.
There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration. The airway, which includes the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles, carries air between the lungs and the body's exterior.
Warfarin is an anticoagulant medication - it is used to slow down the blood-clotting process. Anticoagulants are used to prevent blood clots which may cause vein blockages, heart attack and stroke. Warfarin is known under the brand names Warfant, Jantoven, Coumadin, Lawarin, Marevan, and Waran.
CD4 T-cells (a type of white blood cell) are important to your body's defence against infections. This animation describes how your immune system is weakened by the HIV virus, which targets CD4 T-cells and leads to their gradual decline in number. Low to very low levels of CD4 cells put you at risk for 'opportunistic infections' that take advantage of the body's weakened immune system.
ADC was first identified early in the AIDS epidemic as a common and novel CNS syndrome.(4,5) The three components of the term, AIDS dementia complex embody central features of the condition. AIDS emphasizes its morbidity and poor prognosis, particularly when its severity is at stage 2 or greater (see Table 1), a severity comparable to other clinical AIDS-defining complications of HIV-1 infection. Dementia designates the acquired and persistent cognitive decline with preserved alertness that usually dominates the clinical presentation and determines its principal disability. Complex emphasizes that this disease not only impairs the intellect, but also concomitantly alters motor performance and, at times, behavior. This involvement of the nervous system beyond cognition is evidence of a wider involvement of the CNS than occurs in some other types of dementia such as Alzheimer's disease. Additionally, myelopathy may be an important, indeed predominating, aspect of ADC, and organic psychosis may also be a feature in a subset of patients (see Rheumatologic and Musculoskeletal Manifestations of HIV). These manifestations are therefore also encompassed within this term. By contrast, neither neuropathy nor functional psychiatric disturbance are included in ADC.
This is a Video in Clinical Medicine from the New England Journal of Medicine. Tympanocentesis in Children with Acute Otitis Media Overview Tympanocentesis is defined as needle aspiration of fluid from the middle ear. In children with acute otitis media, drainage of pus from the middle ear results in a rapid and marked improvement in symptoms and enables the clinician to prescribe tailored antimicrobial therapy. This video will demonstrate the technique of tympanocentesis. Indications Tympanocentesis is recommended in children with refractory acute otitis media, in immunocompromised children with otitis media, and in children with suppurative complications of acute otitis media, . . . .
TransMedics’ proprietary Organ Care System (OCS) is the first commercial and portable warm blood perfusion organ transport system. With the OCS, doctors are able to perform “living organ transplants,” where organs are kept warm and functioning in a controlled environment from the time they are recovered to the moment they are placed in the recipient’s body.