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The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column. The brain and spinal cord together make up the central nervous system (CNS).
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.
Your baby is still tiny, but already your body is changing. Your breasts start to swell and may feel tender. Tiredness, nausea, and a frequent need to pee are common pregnancy symptoms. In your second trimester, your growing uterus gradually rises up out of your pelvis.
When a stroke affects an extensive portion of the front and back regions of the left hemisphere, the result may be global aphasia. Survivors with global aphasia: May have great difficulty in understanding words and sentences. May have great difficulty in forming words and sentences. May understand some words. Get out a few words at a time. Have severe difficulties that prevent them from effectively communicating.
Phencyclidine (PCP) was developed in the 1950s as an intravenous anesthetic but, due to the side effects of confusion and delirium, its development for human medical use was discontinued. In its pure form, it is a white crystalline powder that readily dissolves in water or alcohol and has a distinctive bitter chemical taste. On the illicit drug market, Phencyclidine contains a number of contaminants as a result of makeshift manufacturing, causing the color to range from tan to brown, and the consistency to range from powder to a gummy mass. It is available in a variety of tablets, capsules, and colored powders, which are either taken orally or snorted. The liquid form of phencyclidine is actually phencyclidine base dissolved most often in ether, a highly flammable solvent. For smoking, phencyclidine is typically sprayed onto leafy material such as mint, parsley, oregano, or marijuana.
Syringomyelia (sih-ring-go-my-E-lee-uh) is the development of a fluid-filled cyst (syrinx) within your spinal cord. Over time, the cyst may enlarge, damaging your spinal cord and causing pain, weakness and stiffness, among other symptoms. Syringomyelia has several possible causes, though the majority of cases are associated with a condition in which brain tissue protrudes into your spinal canal (Chiari malformation). Other causes of syringomyelia include spinal cord tumors, spinal cord injuries and damage caused by inflammation around your spinal cord. If syringomyelia isn't causing any problems, monitoring the condition may be all that's necessary. But if you're bothered by symptoms, you may need surgery.
Instead of permanently joining (fusing) vertebrae with metal rods and screws, and therefore restricting movement, the new procedure uses the Anatomic Facet Replacement System (AFRS) device that attaches to each of two adjacent vertebrae with a movable joint that mimics the spine's natural joint.
Liddle syndrome is an inherited form of high blood pressure (hypertension). This condition is characterized by severe hypertension that begins unusually early in life, often in childhood, although some affected individuals are not diagnosed until adulthood. Some people with Liddle syndrome have no additional signs or symptoms, especially in childhood. Over time, however, untreated hypertension can lead to heart disease or stroke, which may be fatal.
In Reye's syndrome, a child's blood sugar level typically drops while the levels of ammonia and acidity in his or her blood rise. At the same time, the liver may swell and develop fatty deposits. Swelling may also occur in the brain, which can cause seizures, convulsions or loss of consciousness. The signs and symptoms of Reye's syndrome typically appear about three to five days after the onset of a viral infection, such as the flu (influenza) or chickenpox, or an upper respiratory infection, such as a cold
Therapeutic anticoagulation is recommended for all women with acute VTE; prophylactic anticoagulation is recommended for women at risk, such as those with a past history of thrombosis or thrombophilia or with a mechanical heart valve. The preferred anticoagulants during pregnancy are the heparin compounds.
Emphysema, also known as COPD, is a chronic condition with multiple factors that impact survival and life expectancy. Stages of COPD are generally defined using the GOLD criteria (Global Initiative for Chronic Obstructive Lung Disease). It has four levels or stages: mild - or Stage 1.
Atherosclerosis is a narrowing of the arteries caused by a buildup of plaque. It’s also called arteriosclerosis or hardening of the arteries. Arteries are the blood vessels that carry oxygen and nutrients from your heart to the rest of your body. As you get older, fat and cholesterol can collect in your arteries and form plaque. The buildup of plaque makes it difficult for blood to flow through your arteries. This buildup may occur in any artery in your body and can result in a shortage of blood and oxygen in various tissues of your body. Pieces of plaque can also break off, causing a blood clot. Atherosclerosis can lead to heart attack, stroke, or heart failure if left untreated.
S-ICD leaves the heart and vasculature untouched. It may be implanted using only anatomical landmarks, thereby eliminating the need for fluoroscopy during implant and therefore reducing radiation exposure for both patients and physicians and eliminating the need for lead apron during implant.
ARDS was recognized as the most severe form of acute lung injury (ALI), a form of diffuse alveolar injury. The AECC defined ARDS as an acute condition characterized by bilateral pulmonary infiltrates and severe hypoxemia in the absence of evidence for cardiogenic pulmonary edema. The severity of hypoxemia necessary to make the diagnosis of ARDS was defined by the ratio of the partial pressure of oxygen in the patient’s arterial blood (PaO2) to the fraction of oxygen in the inspired air (FiO2). ARDS was defined by a PaO2/FiO2 ratio of less than 200, and in ALI, less than 300. This definition was further refined in 2011 by a panel of experts and is termed the Berlin definition of ARDS. [3] ARDS is defined by timing (within 1 wk of clinical insult or onset of respiratory symptoms); radiographic changes (bilateral opacities not fully explained by effusions, consolidation, or atelectasis); origin of edema (not fully explained by cardiac failure or fluid overload); and severity based on the PaO2/FiO2 ratio on 5 cm of continuous positive airway pressure (CPAP). The 3 categories are mild (PaO2/FiO2 200-300), moderate (PaO2/FiO2 100-200), and severe (PaO2/FiO2 ≤100).
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.