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Smoking causes: Chronic obstructive pulmonary disease (COPD), a disease that gets worse over time and causes wheezing, shortness of breath, chest tightness, and other symptoms. Emphysema, a condition in which the walls between the air sacs in your lungs lose their ability to stretch and shrink back.
A pheochromocytoma (fee-o-kroe-moe-sy-TOE-muh) is a rare, usually noncancerous (benign) tumor that develops in cells in the center of an adrenal gland. You have two adrenal glands, one above each kidney. Your adrenal glands produce hormones that give instructions to virtually every organ and tissue in your body. If you have a pheochromocytoma, an adrenal gland releases hormones that cause persistent or episodic high blood pressure. If left untreated, a pheochromocytoma can result in severe or life-threatening damage to other body systems, especially the cardiovascular system. Most people with a pheochromocytoma are between the ages of 20 and 50, but the tumor can develop at any age. Surgical treatment to remove a pheochromocytoma usually returns blood pressure to normal.
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.
Endometrial cancer is a type of cancer that begins in the uterus. The uterus is the hollow, pear-shaped pelvic organ in women where fetal development occurs. Endometrial cancer begins in the layer of cells that form the lining (endometrium) of the uterus. Endometrial cancer is sometimes called uterine cancer. Other types of cancer can form in the uterus, including uterine sarcoma, but they are much less common than endometrial cancer. Endometrial cancer is often detected at an early stage because it frequently produces abnormal vaginal bleeding, which prompts women to see their doctors. If endometrial cancer is discovered early, removing the uterus surgically often cures endometrial cancer.
Systemic circulation carries oxygenated blood from the left ventricle, through the arteries, to the capillaries in the tissues of the body. From the tissue capillaries, the deoxygenated blood returns through a system of veins to the right atrium of the heart.
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.
In most instances, STDs are passed from an infected person to another person during sexual activities, through contact with the mucous membranes of the penis, vagina, mouth and rectum. Such activity includes vaginal, oral and anal intercourse. Gonorrhea and chlamydia also can be transmitted by fingers to eyes. A sexually transmissible infection (STI) is any infection or disease that can be passed from one person to another during sexual activity. Sexually transmissible infections include chlamydia, herpes, gonorrhoea, syphilis, genital herpes, scabies, pubic lice (crabs), hepatitis and HIV (the virus that causes AIDS).
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 heart attack is a medical emergency. A heart attack usually occurs when a blood clot blocks blood flow to the heart. Without blood, tissue loses oxygen and dies. Symptoms include tightness or pain in the chest, neck, back, or arms, as well as fatigue, lightheadedness, abnormal heartbeat, and anxiety. Women are more likely to have atypical symptoms than men. Treatment ranges from lifestyle changes and cardiac rehabilitation to medications, stents, and bypass surgery.
Dacryocystorhinostomy (DCR) is a procedure performed for the treatment of tearing (epiphora) due to blockage of the nasolacrimal duct. Tears originate in the lacrimal gland, located at the upper outer margin of the eye. As tears cross the eye with each blink, they are directed into small openings in the eyelids called puncta. From this point, tears travel through a pathway known as the canalicular system into the lacrimal sac. The lacrimal sac is located between the eye and the nose, and funnels tears into the nasal cavity through the nasolacrimal duct (Figure 1). As this is quite a long path for tears to travel, there can be many causes of excessive tearing. Blockage of the nasolacrimal duct is one common cause, and can be treated by creating a direct opening from the lacrimal sac into the nasal cavity in a procedure known as DCR. The evaluation and management of tearing may involve both an ophthalmologist and an otolaryngologist.
Embryonic cardiovascular system. ... The human arterial and venous systems develop from different embryonic areas. Aortic Arches. The aortic arches—or pharyngeal arch arteries—are a series of six, paired, embryological vascular structures that give rise to several major arteries .
The rotator cuff is a group of muscles and tendons that surround the shoulder joint, keeping the head of your upper arm bone firmly within the shallow socket of the shoulder. A rotator cuff injury can cause a dull ache in the shoulder, which often worsens when you try to sleep on the involved side. Rotator cuff injuries occur most often in people who repeatedly perform overhead motions in their jobs or sports. Examples include painters, carpenters, and people who play baseball or tennis. The risk of rotator cuff injury also increases with age. Many people recover from rotator cuff disease with physical therapy exercises that improve flexibility and strength of the muscles surrounding the shoulder joint. Sometimes, rotator cuff tears may occur as a result of a single injury. In those circumstances, medical care should be provided as soon as possible. Extensive rotator cuff tears may require surgical repair, transfer of alternative tendons or joint replacement.
Genes are the building blocks of heredity. They are passed from parent to child. They hold DNA, the instructions for making proteins. Proteins do most of the work in cells. They move molecules from one place to another, build structures, break down toxins, and do many other maintenance jobs. Sometimes there is a mutation, a change in a gene or genes. The mutation changes the gene's instructions for making a protein, so the protein does not work properly or is missing entirely. This can cause a medical condition called a genetic disorder. You can inherit a gene mutation from one or both parents. A mutation can also happen during your lifetime.
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.
Alcohol not broken down by the liver goes to the rest of the body, including the brain. Alcohol can affect parts of the brain that control movement, speech, judgment, and memory. These effects lead to the familiar signs of drunkenness: difficulty walking, slurred speech, memory lapses, and impulsive behavior.