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Sound waves enter the ear canal and make the ear drum vibrate. This action moves the tiny chain of bones (ossicles – malleus, incus, stapes) in the middle ear. The last bone in this chain 'knocks' on the membrane window of the cochlea and makes the fluid in the cochlea move.
Erectile dysfunction (ED) is the inability to get or keep an erection firm enough for sexual function. It’s a common sexual problem, affecting as many as 30 million men in the United States. Most cases of ED have a physical cause, such as heart disease, diabetes, and obesity. Lifestyle choices like smoking and drinking excessive amounts of alcohol can also lead to ED. But for some men, psychological issues are the root of the problem.
Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is a chronic liver disease resulting from progressive destruction of the bile ducts in the liver – called the intrahepatic bile ducts. Bile produced in your liver travels via these ducts to your small intestine where it aids in the digestion of fat and fat-soluble vitamins (A, D, E and K). When the ducts are destroyed, bile builds up in the liver contributing to inflammation and scarring (fibrosis). Eventually this can lead to cirrhosis and its associated complications, as scar tissue replaces healthy liver tissue and liver function becomes increasingly impaired.
Has your dentist or endodontist told you that you need root canal treatment? If so, you're not alone. Millions of teeth are treated and saved each year with root canal, or endodontic, treatment. Remember, root canal treatment doesn't cause pain, it relieves it. Watch our videos below to learn more! Inside the tooth, under the white enamel and a hard layer called the dentin, is a soft tissue called the pulp. The pulp contains blood vessels, nerves and connective tissue, and helps to grow the root of your tooth during development. In a fully developed tooth, the tooth can survive without the pulp because the tooth continues to be nourished by the tissues surrounding it.
Distal Humerus Fractures of the Elbow. A distal humerus fracture is a break in the lower end of the upper arm bone (humerus), one of the three bones that come together to form the elbow joint. A fracture in this area can be very painful and make elbow motion difficult or impossible.
Norepinephrine is synthesized from dopamine by dopamine β-hydroxylase.[7] It is released from the adrenal medulla into the blood as a hormone, and is also a neurotransmitter in the central nervous system and sympathetic nervous system where it is released from noradrenergic neurons.
In a normal person, when a muscle tendon is tapped briskly, the muscle immediately contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle. The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon organ associated with the muscles; the efferent neuron is an alpha motoneuron in the anterior horn of the cord. The cerebral cortex and a number of brainstem nuclei exert influence over the sensory input of the muscle spindles by means of the gamma motoneurons that are located in the anterior horn; these neurons supply a set of muscle fibers that control the length of the muscle spindle itself.
At each level of the spine, there is a disc space in the front and paired facet joints in the back. Working together, these structures define a motion segment (Fig. 1A). Back pain may result when injury or degenerative changes allow abnormal movement of the vertebrae to rub against one another, known as an unstable motion segment (Fig. 1B). Two vertebrae need to be fused to stop the motion at one segment. For example, an L4-L5 fusion is a one-level spinal fusion (Fig. 1C). A two-level fusion joins three vertebrae together and so on.
Your temporomandibular joint is a hinge that connects your jaw to the temporal bones of your skull, which are in front of each ear. It lets you move your jaw up and down and side to side, so you can talk, chew, and yawn. Problems with your jaw and the muscles in your face that control it are known as temporomandibular disorders (TMD). But you may hear it wrongly called TMJ, after the joint.
This surgery is usually done while you are under general anesthesia. That means you will be asleep and pain-free. Healthy skin is taken from a place on your body called the donor site. Most people who are having a skin graft have a split-thickness skin graft. This takes the two top layers of skin from the donor site (the epidermis) and the layer under the epidermis (the dermis). The donor site can be any area of the body. Most times, it is an area that is hidden by clothes, such as the buttock or inner thigh. The graft is carefully spread on the bare area where it is being transplanted. It is held in place either by gentle pressure from a well-padded dressing that covers it, or by staples or a few small stitches. The donor-site area is covered with a sterile dressing for 3 to 5 days. People with deeper tissue loss may need a full-thickness skin graft. This requires an entire thickness of skin from the donor site, not just the top two layers. A full-thickness skin graft is a more complicated procedure. Common donor sites for full-thickness skin grafts include the chest wall, back, or abdominal wall.