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Cisplatin is in a class of drugs known as platinum-containing compounds used to treat various types of cancers including metastatic testicular and ovarian tumors. The molecule was first discovered in 1845, but did not receive FDA approval until 1978. Today it is known as the "penicillin of cancer drugs," because it is so effective for many different cancers. There are three key players involved in Cisplatin's mechanism: (1) Cisplatin, (2) DNA (3) and an HMG Protein. Most Cisplatin enters the body through active transport, but some molecules are passively defused through the cell membrane. Once in the nucleus, Cisplatin can form an adduct with two consecutive guanine bases within a strand of DNA. The molecule loses its chlorine atoms in exchange for the nitrogen atoms of the target guanines. Cisplatin can bond more tightly with nitrogen because nitrogen balances the platinum charge more effectively than chlorine. It is this adduct-induced DNA bend that allows binding of proteins which contain the high mobility group, HMG domain. Once the protein is bound to the DNA, it inserts a wedge-like phenyl group of phenylalanine 37 into the widened minor groove created by the bend. The tightly bound HMG protein causes destacking of the nucleotide bases, resulting in the DNA helix becoming kinked. In this way, Cisplatin can be thought of as a monkey wrench in the DNA repair system. With the HMG protein bound to the DNA, the modified strand is not repaired properly and so the cell dies. The success of Cisplatin depends on its ratio of efficacy between cancerous and healthy cells.

Galant Reflex

Histology of Tongue Circumvallate Papilla

Polycystic ovary syndrome is a common endocrine system disorder among women of reproductive age. Women with PCOS may have enlarged ovaries that contain small collections of fluid — called follicles — located in each ovary as seen during an ultrasound exam. Infrequent or prolonged menstrual periods, excess hair growth, acne, and obesity can all occur in women with polycystic ovary syndrome. In adolescents, infrequent or absent menstruation may raise suspicion for the condition. The exact cause of polycystic ovary syndrome is unknown. Early diagnosis and treatment along with weight loss may reduce the risk of long-term complications, such as type 2 diabetes and heart disease.

Polycystic liver disease (PLD or PCLD) is a rare condition that causes cysts -- fluid-filled sacs -- to grow throughout the liver. A normal liver has a smooth, uniform appearance. A polycystic liver can look like a cluster of very large grapes.

Remove Acne Marks

Cluster headaches, occur in cyclical patterns or clusters, are one of the most painful types of headache. A cluster headache commonly awakens you in the middle of the night with intense pain in or around one eye on one side of your head. Bouts of frequent attacks, known as cluster periods, can last from weeks to months, usually followed by remission periods when the headaches stop. During remission, no headaches occur for months and sometimes even years. Fortunately, cluster headache is rare and not life-threatening. Treatments can make cluster headache attacks shorter and less severe. In addition, medications can reduce the number of cluster headaches.

Treatment may include: Rest. Ice or heat. Nonsteroidal anti-inflammatory medications. Strengthening exercises. Ultrasound therapy. Corticosteroid injection. Surgery (for severe injuries)

If you or someone you love has atrial fibrillation, learn more about what AFib is, why treatment can save lives, and what you can do to reach your goals, lower your risks and live a healthy life.

Function. Vitamin A helps form and maintain healthy skin, teeth, skeletal and soft tissue, mucus membranes, and skin. It is also known as retinol because it produces the pigments in the retina of the eye. Vitamin A promotes good vision, especially in low light. Vitamin deficiency anemia occurs when your body doesn't have enough of the vitamins needed to produce adequate numbers of healthy red blood cells. Red blood cells carry oxygen from your lungs throughout your body. If your diet is lacking in certain vitamins, vitamin deficiency anemia can develop.

Blood type (or blood group) is determined, in part, by the ABO blood group antigens present on red blood cells. A blood type (also called a blood group) is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs).

Knee Examination

Cancer, also called malignancy, is an abnormal growth of cells. There are more than 100 types of cancer, including breast cancer, skin cancer, lung cancer, colon cancer, prostate cancer, and lymphoma. Symptoms vary depending on the type. Cancer treatment may include chemotherapy, radiation, and/or surgery.

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.

Cardiac cath is performed to find out if you have disease of the heart muscle, valves or coronary (heart) arteries. During the procedure, the pressure and blood flow in your heart can be measured. Coronary angiography is done during cardiac catheterization.

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.

Obstetrics is the field of medicine which encompasses the care of a woman during pregnancy and childbirth. In that way it is very unique, as when assessing these patients, your actually also assessing another the child.

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.

The term trisomy is used to describe the presence of three chromosomes, rather than the usual matched pair of chromosomes. For example, if a baby is born with three #21 chromosomes, rather than the usual pair, then the baby would be said to have "trisomy 21." Trisomy 21 is also known as Down syndrome. Other examples of trisomy include syndromes like trisomy 18 and trisomy 13. Again, trisomy 18 or trisomy 13 simply means the child has three copies of the #18 chromosome (or of the #13 chromosome) present in each cell of the body, rather than the usual pair.