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Esophageal manometry is a test used to measure the function of the lower esophageal sphincter (the valve that prevents reflux of gastric acid into the esophagus) and the muscles of the esophagus (see diagram). This test will tell your doctor if your esophagus is able to move food to your stomach normally.
Bipolar disorder, also known as manic-depressive illness, is a brain disorder that causes unusual shifts in mood, energy, activity levels, and the ability to carry out day-to-day tasks. There are four basic types of bipolar disorder; all of them involve clear changes in mood, energy, and activity levels.
Watch as Dr. Benjamin Carson performs risky brain surgery on young Payton to remove a brain tumor. Dr. Carson, director of pediatric neurosurgery, is just one of the many reasons why Johns Hopkins Children's Center was recently ranked #1 in neurology and neurosurgery in America's Best Children's Hospitals 2008
ThermiVa is a non-surgical vaginal tightening treatment for women who want to reclaim what childbirth or aging may have taken away. Using the same technology that’s used in ThermiTight and ThermiSmooth, radiofrequency energy is sent to the desired area (internally or externally), heating the tissue and stimulating the body’s own collagen. ThermiVa is performed in three treatments over the course of three months.
Wilson's disease is a rare inherited disorder that causes too much copper to accumulate in your liver, brain and other vital organs. Symptoms typically begin between the ages of 12 and 23. Copper plays a key role in the development of healthy nerves, bones, collagen and the skin pigment melanin. Normally, copper is absorbed from your food, and any excess is excreted through bile — a substance produced in your liver. But in people with Wilson's disease, copper isn't eliminated properly and instead accumulates, possibly to a life-threatening level. When diagnosed early, Wilson's disease is treatable, and many people with the disorder live normal lives.
Electronystagmography (ENG) is a diagnostic test to record involuntary movements of the eye caused by a condition known as nystagmus. It can also be used to diagnose the cause of vertigo, dizziness or balance dysfunction by testing the vestibular system.
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.
Pulmonary surfactant is a mixture of lipids and proteins that is produced by alveolar type II epithelial cells (AEC2) and secreted into the airspaces. Phospholipids are the major component of surfactant by weight, and are essential for lowering surface tension at the air-liquid interface, which prevents alveolar collapse at end-expiration. Four proteins highly expressed in the lung and found in surfactant are designated surfactant proteins (SP) A, B, C, and D. Additional proteins including ABCA3 and NKX2.1 are also important for the production of functional surfactant. The surfactant proteins are developmentally regulated, such that their expression increases in later gestation
Any independent vertical movement of the transducer or the patient will affect the hydrostatic column of this fluid-filled system and thus alter the pressure measurements. At some time before or after PAC insertion, the system must therefore be zeroed to ambient air pressure. The reference point for this is the midpoint of the left atrium (LA), estimated as the fourth intercostal space in the midaxillary line with the patient in the supine position. With the transducer at this height, the membrane is exposed to atmospheric pressure, and the monitor is then adjusted to zero. Calibration Once zeroed, the monitoring system must be calibrated for accuracy. Currently, most monitors perform an automated electronic calibration. Two methods are used to manually calibrate and check the system. If the catheter has not been inserted, the distal tip of the PAC is raised to a specified height above the LA. For example, raising the tip 20 cm above the LA should produce a reading of approximately 15 mm Hg if the system is working properly (1 mm Hg equals 1.36 cm H 2 O). Alternatively, pressure can be applied externally to the transducer and adjusted to a known level using a mercury or aneroid manometer. The monitor then is adjusted to read this pressure, and the system is calibrated. Dynamic tuning Central pressures are dynamic waveforms (ie, they vary from systole to diastole) and thus have a periodic frequency. To monitor these pressures accurately, the system requires an appropriate frequency response. A poorly responsive system produces inaccurate pressure readings, and differentiating waveforms (eg, PA from pulmonary capillary wedge pressure [PCWP]) can become difficult. When signal energy is lost, the pressure waveform is dampened. Common causes of this are air bubbles (which are compressible), long or compliant tubing, vessel wall impingement, intracatheter debris, transducer malfunction, and loose connections in the tubing. A qualitative test of the frequency response is performed by flicking the catheter and observing a brisk high-frequency response in the waveform. After insertion, the system can be checked by using the rapid flush test. When flushed, an appropriately responsive system shows an initial horizontal straight line with a high-pressure reading. Once the flushing is terminated, the pressure drops immediately, which is represented by a vertical line that plunges below the baseline. A brief and well-defined oscillation occurs, followed by return of the PA waveform. A dampened system will not overshoot or oscillate, and causes a delay in returning to the PA waveform.
A liver abscess is a pus-filled mass inside the liver. Common causes are abdominal infections such as appendicitis or diverticulitis due to haematogenous spread through the portal vein. A pyogenic liver abscess (PLA) is a pocket of pus that forms in the liver in response to an infection or trauma. Pus is a fluid composed of white blood cells, dead cells, and bacteria that forms when your body fights off infection.Dec 11, 2015